diff --git a/adb/Android.bp b/adb/Android.bp
index 3813578..1e085a7 100644
--- a/adb/Android.bp
+++ b/adb/Android.bp
@@ -402,6 +402,14 @@
         "liblog",
     ],
 
+    product_variables: {
+        debuggable: {
+            required: [
+                "remount",
+            ],
+        },
+    },
+
     target: {
         android: {
             srcs: [
diff --git a/adb/adb.cpp b/adb/adb.cpp
index a5b2f7b..3c07882 100644
--- a/adb/adb.cpp
+++ b/adb/adb.cpp
@@ -1018,9 +1018,10 @@
     return 0;
 }
 
-bool handle_host_request(const char* service, TransportType type, const char* serial,
-                        TransportId transport_id, int reply_fd, asocket* s) {
-    if (strcmp(service, "kill") == 0) {
+HostRequestResult handle_host_request(std::string_view service, TransportType type,
+                                      const char* serial, TransportId transport_id, int reply_fd,
+                                      asocket* s) {
+    if (service == "kill") {
         fprintf(stderr, "adb server killed by remote request\n");
         fflush(stdout);
 
@@ -1032,29 +1033,49 @@
         exit(0);
     }
 
-    // "transport:" is used for switching transport with a specified serial number
-    // "transport-usb:" is used for switching transport to the only USB transport
-    // "transport-local:" is used for switching transport to the only local transport
-    // "transport-any:" is used for switching transport to the only transport
-    if (!strncmp(service, "transport", strlen("transport"))) {
+    LOG(DEBUG) << "handle_host_request(" << service << ")";
+
+    // Transport selection:
+    if (service.starts_with("transport") || service.starts_with("tport:")) {
         TransportType type = kTransportAny;
 
-        if (!strncmp(service, "transport-id:", strlen("transport-id:"))) {
-            service += strlen("transport-id:");
-            transport_id = strtoll(service, const_cast<char**>(&service), 10);
-            if (*service != '\0') {
-                SendFail(reply_fd, "invalid transport id");
-                return true;
+        std::string serial_storage;
+        bool legacy = true;
+
+        // New transport selection protocol:
+        // This is essentially identical to the previous version, except it returns the selected
+        // transport id to the caller as well.
+        if (ConsumePrefix(&service, "tport:")) {
+            legacy = false;
+            if (ConsumePrefix(&service, "serial:")) {
+                serial_storage = service;
+                serial = serial_storage.c_str();
+            } else if (service == "usb") {
+                type = kTransportUsb;
+            } else if (service == "local") {
+                type = kTransportLocal;
+            } else if (service == "any") {
+                type = kTransportAny;
             }
-        } else if (!strncmp(service, "transport-usb", strlen("transport-usb"))) {
-            type = kTransportUsb;
-        } else if (!strncmp(service, "transport-local", strlen("transport-local"))) {
-            type = kTransportLocal;
-        } else if (!strncmp(service, "transport-any", strlen("transport-any"))) {
-            type = kTransportAny;
-        } else if (!strncmp(service, "transport:", strlen("transport:"))) {
-            service += strlen("transport:");
-            serial = service;
+
+            // Selection by id is unimplemented, since you obviously already know the transport id
+            // you're connecting to.
+        } else {
+            if (ConsumePrefix(&service, "transport-id:")) {
+                if (!ParseUint(&transport_id, service)) {
+                    SendFail(reply_fd, "invalid transport id");
+                    return HostRequestResult::Handled;
+                }
+            } else if (service == "transport-usb") {
+                type = kTransportUsb;
+            } else if (service == "transport-local") {
+                type = kTransportLocal;
+            } else if (service == "transport-any") {
+                type = kTransportAny;
+            } else if (ConsumePrefix(&service, "transport:")) {
+                serial_storage = service;
+                serial = serial_storage.c_str();
+            }
         }
 
         std::string error;
@@ -1063,27 +1084,29 @@
             s->transport = t;
             SendOkay(reply_fd);
 
-            // We succesfully handled the device selection, but there's another request coming.
-            return false;
+            if (!legacy) {
+                // Nothing we can do if this fails.
+                WriteFdExactly(reply_fd, &t->id, sizeof(t->id));
+            }
+
+            return HostRequestResult::SwitchedTransport;
         } else {
             SendFail(reply_fd, error);
-            return true;
+            return HostRequestResult::Handled;
         }
     }
 
     // return a list of all connected devices
-    if (!strncmp(service, "devices", 7)) {
-        bool long_listing = (strcmp(service+7, "-l") == 0);
-        if (long_listing || service[7] == 0) {
-            D("Getting device list...");
-            std::string device_list = list_transports(long_listing);
-            D("Sending device list...");
-            SendOkay(reply_fd, device_list);
-        }
-        return true;
+    if (service == "devices" || service == "devices-l") {
+        bool long_listing = service == "devices-l";
+        D("Getting device list...");
+        std::string device_list = list_transports(long_listing);
+        D("Sending device list...");
+        SendOkay(reply_fd, device_list);
+        return HostRequestResult::Handled;
     }
 
-    if (!strcmp(service, "reconnect-offline")) {
+    if (service == "reconnect-offline") {
         std::string response;
         close_usb_devices([&response](const atransport* transport) {
             if (!ConnectionStateIsOnline(transport->GetConnectionState())) {
@@ -1096,10 +1119,10 @@
             response.resize(response.size() - 1);
         }
         SendOkay(reply_fd, response);
-        return true;
+        return HostRequestResult::Handled;
     }
 
-    if (!strcmp(service, "features")) {
+    if (service == "features") {
         std::string error;
         atransport* t = acquire_one_transport(type, serial, transport_id, nullptr, &error);
         if (t != nullptr) {
@@ -1107,10 +1130,10 @@
         } else {
             SendFail(reply_fd, error);
         }
-        return true;
+        return HostRequestResult::Handled;
     }
 
-    if (!strcmp(service, "host-features")) {
+    if (service == "host-features") {
         FeatureSet features = supported_features();
         // Abuse features to report libusb status.
         if (should_use_libusb()) {
@@ -1118,16 +1141,16 @@
         }
         features.insert(kFeaturePushSync);
         SendOkay(reply_fd, FeatureSetToString(features));
-        return true;
+        return HostRequestResult::Handled;
     }
 
     // remove TCP transport
-    if (!strncmp(service, "disconnect:", 11)) {
-        const std::string address(service + 11);
+    if (service.starts_with("disconnect:")) {
+        std::string address(service.substr(11));
         if (address.empty()) {
             kick_all_tcp_devices();
             SendOkay(reply_fd, "disconnected everything");
-            return true;
+            return HostRequestResult::Handled;
         }
 
         std::string serial;
@@ -1139,26 +1162,26 @@
         } else if (!android::base::ParseNetAddress(address, &host, &port, &serial, &error)) {
             SendFail(reply_fd, android::base::StringPrintf("couldn't parse '%s': %s",
                                                            address.c_str(), error.c_str()));
-            return true;
+            return HostRequestResult::Handled;
         }
         atransport* t = find_transport(serial.c_str());
         if (t == nullptr) {
             SendFail(reply_fd, android::base::StringPrintf("no such device '%s'", serial.c_str()));
-            return true;
+            return HostRequestResult::Handled;
         }
         kick_transport(t);
         SendOkay(reply_fd, android::base::StringPrintf("disconnected %s", address.c_str()));
-        return true;
+        return HostRequestResult::Handled;
     }
 
     // Returns our value for ADB_SERVER_VERSION.
-    if (!strcmp(service, "version")) {
+    if (service == "version") {
         SendOkay(reply_fd, android::base::StringPrintf("%04x", ADB_SERVER_VERSION));
-        return true;
+        return HostRequestResult::Handled;
     }
 
     // These always report "unknown" rather than the actual error, for scripts.
-    if (!strcmp(service, "get-serialno")) {
+    if (service == "get-serialno") {
         std::string error;
         atransport* t = acquire_one_transport(type, serial, transport_id, nullptr, &error);
         if (t) {
@@ -1166,9 +1189,9 @@
         } else {
             SendFail(reply_fd, error);
         }
-        return true;
+        return HostRequestResult::Handled;
     }
-    if (!strcmp(service, "get-devpath")) {
+    if (service == "get-devpath") {
         std::string error;
         atransport* t = acquire_one_transport(type, serial, transport_id, nullptr, &error);
         if (t) {
@@ -1176,9 +1199,9 @@
         } else {
             SendFail(reply_fd, error);
         }
-        return true;
+        return HostRequestResult::Handled;
     }
-    if (!strcmp(service, "get-state")) {
+    if (service == "get-state") {
         std::string error;
         atransport* t = acquire_one_transport(type, serial, transport_id, nullptr, &error);
         if (t) {
@@ -1186,39 +1209,46 @@
         } else {
             SendFail(reply_fd, error);
         }
-        return true;
+        return HostRequestResult::Handled;
     }
 
     // Indicates a new emulator instance has started.
-    if (!strncmp(service, "emulator:", 9)) {
-        int  port = atoi(service+9);
-        local_connect(port);
+    if (ConsumePrefix(&service, "emulator:")) {
+        unsigned int port;
+        if (!ParseUint(&port, service)) {
+          LOG(ERROR) << "received invalid port for emulator: " << service;
+        } else {
+          local_connect(port);
+        }
+
         /* we don't even need to send a reply */
-        return true;
+        return HostRequestResult::Handled;
     }
 
-    if (!strcmp(service, "reconnect")) {
+    if (service == "reconnect") {
         std::string response;
         atransport* t = acquire_one_transport(type, serial, transport_id, nullptr, &response, true);
         if (t != nullptr) {
             kick_transport(t);
             response =
-                "reconnecting " + t->serial_name() + " [" + t->connection_state_name() + "]\n";
+                    "reconnecting " + t->serial_name() + " [" + t->connection_state_name() + "]\n";
         }
         SendOkay(reply_fd, response);
-        return true;
+        return HostRequestResult::Handled;
     }
 
-    if (handle_forward_request(service,
-                               [=](std::string* error) {
-                                   return acquire_one_transport(type, serial, transport_id, nullptr,
-                                                                error);
-                               },
-                               reply_fd)) {
-        return true;
+    // TODO: Switch handle_forward_request to string_view.
+    std::string service_str(service);
+    if (handle_forward_request(
+                service_str.c_str(),
+                [=](std::string* error) {
+                    return acquire_one_transport(type, serial, transport_id, nullptr, error);
+                },
+                reply_fd)) {
+        return HostRequestResult::Handled;
     }
 
-    return false;
+    return HostRequestResult::Unhandled;
 }
 
 static auto& init_mutex = *new std::mutex();
diff --git a/adb/adb.h b/adb/adb.h
index 9209997..c60dcbc 100644
--- a/adb/adb.h
+++ b/adb/adb.h
@@ -59,7 +59,7 @@
 std::string adb_version();
 
 // Increment this when we want to force users to start a new adb server.
-#define ADB_SERVER_VERSION 40
+#define ADB_SERVER_VERSION 41
 
 using TransportId = uint64_t;
 class atransport;
@@ -145,7 +145,8 @@
 #endif
 
 #if ADB_HOST
-asocket* host_service_to_socket(const char* name, const char* serial, TransportId transport_id);
+asocket* host_service_to_socket(std::string_view name, std::string_view serial,
+                                TransportId transport_id);
 #endif
 
 #if !ADB_HOST
@@ -153,7 +154,7 @@
 #endif
 
 #if !ADB_HOST
-unique_fd execute_binder_command(std::string_view command);
+unique_fd execute_abb_command(std::string_view command);
 #endif
 
 #if !ADB_HOST
@@ -218,8 +219,15 @@
 #define USB_FFS_ADB_IN USB_FFS_ADB_EP(ep2)
 #endif
 
-bool handle_host_request(const char* service, TransportType type, const char* serial,
-                         TransportId transport_id, int reply_fd, asocket* s);
+enum class HostRequestResult {
+    Handled,
+    SwitchedTransport,
+    Unhandled,
+};
+
+HostRequestResult handle_host_request(std::string_view service, TransportType type,
+                                      const char* serial, TransportId transport_id, int reply_fd,
+                                      asocket* s);
 
 void handle_online(atransport* t);
 void handle_offline(atransport* t);
diff --git a/adb/adb_io.cpp b/adb/adb_io.cpp
index 91b0d1f..f5cdcb5 100644
--- a/adb/adb_io.cpp
+++ b/adb/adb_io.cpp
@@ -34,7 +34,7 @@
 #include "adb_utils.h"
 #include "sysdeps.h"
 
-bool SendProtocolString(int fd, const std::string& s) {
+bool SendProtocolString(int fd, std::string_view s) {
     unsigned int length = s.size();
     if (length > MAX_PAYLOAD - 4) {
         errno = EMSGSIZE;
@@ -69,7 +69,7 @@
     return WriteFdExactly(fd, "OKAY", 4);
 }
 
-bool SendFail(int fd, const std::string& reason) {
+bool SendFail(int fd, std::string_view reason) {
     return WriteFdExactly(fd, "FAIL", 4) && SendProtocolString(fd, reason);
 }
 
diff --git a/adb/adb_io.h b/adb/adb_io.h
index e2df1b1..d6e65d8 100644
--- a/adb/adb_io.h
+++ b/adb/adb_io.h
@@ -20,6 +20,7 @@
 #include <sys/types.h>
 
 #include <string>
+#include <string_view>
 
 #include "adb_unique_fd.h"
 
@@ -27,10 +28,10 @@
 bool SendOkay(int fd);
 
 // Sends the protocol "FAIL" message, with the given failure reason.
-bool SendFail(int fd, const std::string& reason);
+bool SendFail(int fd, std::string_view reason);
 
 // Writes a protocol-format string; a four hex digit length followed by the string data.
-bool SendProtocolString(int fd, const std::string& s);
+bool SendProtocolString(int fd, std::string_view s);
 
 // Reads a protocol-format string; a four hex digit length followed by the string data.
 bool ReadProtocolString(int fd, std::string* s, std::string* error);
diff --git a/adb/adb_utils.h b/adb/adb_utils.h
index a85ca8c..5800a62 100644
--- a/adb/adb_utils.h
+++ b/adb/adb_utils.h
@@ -110,7 +110,7 @@
 
 // Base-10 stroll on a string_view.
 template <typename T>
-inline bool ParseUint(T* result, std::string_view str, std::string_view* remaining) {
+inline bool ParseUint(T* result, std::string_view str, std::string_view* remaining = nullptr) {
     if (str.empty() || !isdigit(str[0])) {
         return false;
     }
@@ -135,6 +135,17 @@
     *result = value;
     if (remaining) {
         *remaining = str.substr(it - str.begin());
+    } else {
+      return it == str.end();
     }
+
     return true;
 }
+
+inline bool ConsumePrefix(std::string_view* str, std::string_view prefix) {
+  if (str->starts_with(prefix)) {
+    str->remove_prefix(prefix.size());
+    return true;
+  }
+  return false;
+}
diff --git a/adb/adb_utils_test.cpp b/adb/adb_utils_test.cpp
index 8518e17..bd676c2 100644
--- a/adb/adb_utils_test.cpp
+++ b/adb/adb_utils_test.cpp
@@ -206,6 +206,14 @@
             EXPECT_EQ(remaining, "foo");
         }
     }
+
+    // With trailing text, without remaining.
+    {
+        std::string text = std::string(string) + "foo";
+        uint32_t value;
+        bool success = ParseUint(&value, text, nullptr);
+        EXPECT_EQ(success, false);
+    }
 }
 
 TEST(adb_utils, ParseUint) {
diff --git a/adb/benchmark_device.py b/adb/benchmark_device.py
index e56ef5a..4d0cf49 100755
--- a/adb/benchmark_device.py
+++ b/adb/benchmark_device.py
@@ -17,6 +17,8 @@
 
 import os
 import statistics
+import subprocess
+import tempfile
 import time
 
 import adb
@@ -56,6 +58,41 @@
     msg = "%s: %d runs: median %.2f MiB/s, mean %.2f MiB/s, stddev: %.2f MiB/s"
     print(msg % (name, len(speeds), median, mean, stddev))
 
+def benchmark_sink(device=None, size_mb=100):
+    if device == None:
+        device = adb.get_device()
+
+    speeds = list()
+    cmd = device.adb_cmd + ["raw", "sink:%d" % (size_mb * 1024 * 1024)]
+
+    with tempfile.TemporaryFile() as tmpfile:
+        tmpfile.truncate(size_mb * 1024 * 1024)
+
+        for _ in range(0, 10):
+            tmpfile.seek(0)
+            begin = time.time()
+            subprocess.check_call(cmd, stdin=tmpfile)
+            end = time.time()
+            speeds.append(size_mb / float(end - begin))
+
+    analyze("sink %dMiB" % size_mb, speeds)
+
+def benchmark_source(device=None, size_mb=100):
+    if device == None:
+        device = adb.get_device()
+
+    speeds = list()
+    cmd = device.adb_cmd + ["raw", "source:%d" % (size_mb * 1024 * 1024)]
+
+    with open(os.devnull, 'w') as devnull:
+        for _ in range(0, 10):
+            begin = time.time()
+            subprocess.check_call(cmd, stdout=devnull)
+            end = time.time()
+            speeds.append(size_mb / float(end - begin))
+
+    analyze("source %dMiB" % size_mb, speeds)
+
 def benchmark_push(device=None, file_size_mb=100):
     if device == None:
         device = adb.get_device()
@@ -110,6 +147,8 @@
 def main():
     device = adb.get_device()
     unlock(device)
+    benchmark_sink(device)
+    benchmark_source(device)
     benchmark_push(device)
     benchmark_pull(device)
 
diff --git a/adb/client/adb_client.cpp b/adb/client/adb_client.cpp
index 0a09d1e..4cf3a74 100644
--- a/adb/client/adb_client.cpp
+++ b/adb/client/adb_client.cpp
@@ -70,46 +70,60 @@
     __adb_server_socket_spec = socket_spec;
 }
 
-static int switch_socket_transport(int fd, std::string* error) {
+static std::optional<TransportId> switch_socket_transport(int fd, std::string* error) {
+    TransportId result;
+    bool read_transport = true;
+
     std::string service;
     if (__adb_transport_id) {
+        read_transport = false;
         service += "host:transport-id:";
         service += std::to_string(__adb_transport_id);
+        result = __adb_transport_id;
     } else if (__adb_serial) {
-        service += "host:transport:";
+        service += "host:tport:serial:";
         service += __adb_serial;
     } else {
         const char* transport_type = "???";
         switch (__adb_transport) {
           case kTransportUsb:
-            transport_type = "transport-usb";
-            break;
+              transport_type = "usb";
+              break;
           case kTransportLocal:
-            transport_type = "transport-local";
-            break;
+              transport_type = "local";
+              break;
           case kTransportAny:
-            transport_type = "transport-any";
-            break;
+              transport_type = "any";
+              break;
           case kTransportHost:
             // no switch necessary
             return 0;
         }
-        service += "host:";
+        service += "host:tport:";
         service += transport_type;
     }
 
     if (!SendProtocolString(fd, service)) {
         *error = perror_str("write failure during connection");
-        return -1;
+        return std::nullopt;
     }
-    D("Switch transport in progress");
+
+    LOG(DEBUG) << "Switch transport in progress: " << service;
 
     if (!adb_status(fd, error)) {
         D("Switch transport failed: %s", error->c_str());
-        return -1;
+        return std::nullopt;
     }
+
+    if (read_transport) {
+        if (!ReadFdExactly(fd, &result, sizeof(result))) {
+            *error = "failed to read transport id from server";
+            return std::nullopt;
+        }
+    }
+
     D("Switch transport success");
-    return 0;
+    return result;
 }
 
 bool adb_status(int fd, std::string* error) {
@@ -133,11 +147,10 @@
     return false;
 }
 
-static int _adb_connect(const std::string& service, std::string* error) {
-    D("_adb_connect: %s", service.c_str());
+static int _adb_connect(std::string_view service, TransportId* transport, std::string* error) {
+    LOG(DEBUG) << "_adb_connect: " << service;
     if (service.empty() || service.size() > MAX_PAYLOAD) {
-        *error = android::base::StringPrintf("bad service name length (%zd)",
-                                             service.size());
+        *error = android::base::StringPrintf("bad service name length (%zd)", service.size());
         return -1;
     }
 
@@ -149,8 +162,15 @@
         return -2;
     }
 
-    if (memcmp(&service[0], "host", 4) != 0 && switch_socket_transport(fd.get(), error)) {
-        return -1;
+    if (!service.starts_with("host")) {
+        std::optional<TransportId> transport_result = switch_socket_transport(fd.get(), error);
+        if (!transport_result) {
+            return -1;
+        }
+
+        if (transport) {
+            *transport = *transport_result;
+        }
     }
 
     if (!SendProtocolString(fd.get(), service)) {
@@ -190,11 +210,15 @@
     return true;
 }
 
-int adb_connect(const std::string& service, std::string* error) {
-    // first query the adb server's version
-    unique_fd fd(_adb_connect("host:version", error));
+int adb_connect(std::string_view service, std::string* error) {
+    return adb_connect(nullptr, service, error);
+}
 
-    D("adb_connect: service %s", service.c_str());
+int adb_connect(TransportId* transport, std::string_view service, std::string* error) {
+    // first query the adb server's version
+    unique_fd fd(_adb_connect("host:version", nullptr, error));
+
+    LOG(DEBUG) << "adb_connect: service: " << service;
     if (fd == -2 && !is_local_socket_spec(__adb_server_socket_spec)) {
         fprintf(stderr, "* cannot start server on remote host\n");
         // error is the original network connection error
@@ -216,7 +240,7 @@
         // Fall through to _adb_connect.
     } else {
         // If a server is already running, check its version matches.
-        int version = ADB_SERVER_VERSION - 1;
+        int version = 0;
 
         // If we have a file descriptor, then parse version result.
         if (fd >= 0) {
@@ -254,7 +278,7 @@
         return 0;
     }
 
-    fd.reset(_adb_connect(service, error));
+    fd.reset(_adb_connect(service, transport, error));
     if (fd == -1) {
         D("_adb_connect error: %s", error->c_str());
     } else if(fd == -2) {
@@ -265,7 +289,6 @@
     return fd.release();
 }
 
-
 bool adb_command(const std::string& service) {
     std::string error;
     unique_fd fd(adb_connect(service, &error));
diff --git a/adb/client/adb_client.h b/adb/client/adb_client.h
index d467539..0a73787 100644
--- a/adb/client/adb_client.h
+++ b/adb/client/adb_client.h
@@ -24,7 +24,10 @@
 
 // Connect to adb, connect to the named service, and return a valid fd for
 // interacting with that service upon success or a negative number on failure.
-int adb_connect(const std::string& service, std::string* _Nonnull error);
+int adb_connect(std::string_view service, std::string* _Nonnull error);
+
+// Same as above, except returning the TransportId for the service that we've connected to.
+int adb_connect(TransportId* _Nullable id, std::string_view service, std::string* _Nonnull error);
 
 // Kill the currently running adb server, if it exists.
 bool adb_kill_server();
diff --git a/adb/client/adb_install.cpp b/adb/client/adb_install.cpp
index 2bf2924..16fa215 100644
--- a/adb/client/adb_install.cpp
+++ b/adb/client/adb_install.cpp
@@ -638,39 +638,43 @@
         fprintf(stdout, "Created child session ID %d.\n", session_id);
         session_ids.push_back(session_id);
 
-        struct stat sb;
-        if (stat(file, &sb) == -1) {
-            fprintf(stderr, "adb: failed to stat %s: %s\n", file, strerror(errno));
-            goto finalize_multi_package_session;
+        // Support splitAPKs by allowing the notation split1.apk:split2.apk:split3.apk as argument.
+        std::vector<std::string> splits = android::base::Split(file, ":");
+
+        for (const std::string& split : splits) {
+            struct stat sb;
+            if (stat(split.c_str(), &sb) == -1) {
+                fprintf(stderr, "adb: failed to stat %s: %s\n", split.c_str(), strerror(errno));
+                goto finalize_multi_package_session;
+            }
+
+            std::string cmd = android::base::StringPrintf(
+                    "%s install-write -S %" PRIu64 " %d %d_%s -", install_cmd.c_str(),
+                    static_cast<uint64_t>(sb.st_size), session_id, i,
+                    android::base::Basename(split).c_str());
+
+            unique_fd local_fd(adb_open(split.c_str(), O_RDONLY | O_CLOEXEC));
+            if (local_fd < 0) {
+                fprintf(stderr, "adb: failed to open %s: %s\n", split.c_str(), strerror(errno));
+                goto finalize_multi_package_session;
+            }
+
+            std::string error;
+            unique_fd remote_fd(adb_connect(cmd, &error));
+            if (remote_fd < 0) {
+                fprintf(stderr, "adb: connect error for write: %s\n", error.c_str());
+                goto finalize_multi_package_session;
+            }
+
+            copy_to_file(local_fd.get(), remote_fd.get());
+            read_status_line(remote_fd.get(), buf, sizeof(buf));
+
+            if (strncmp("Success", buf, 7)) {
+                fprintf(stderr, "adb: failed to write %s\n", split.c_str());
+                fputs(buf, stderr);
+                goto finalize_multi_package_session;
+            }
         }
-
-        std::string cmd =
-                android::base::StringPrintf("%s install-write -S %" PRIu64 " %d %d_%s -",
-                                            install_cmd.c_str(), static_cast<uint64_t>(sb.st_size),
-                                            session_id, i, android::base::Basename(file).c_str());
-
-        unique_fd local_fd(adb_open(file, O_RDONLY | O_CLOEXEC));
-        if (local_fd < 0) {
-            fprintf(stderr, "adb: failed to open %s: %s\n", file, strerror(errno));
-            goto finalize_multi_package_session;
-        }
-
-        std::string error;
-        unique_fd remote_fd(adb_connect(cmd, &error));
-        if (remote_fd < 0) {
-            fprintf(stderr, "adb: connect error for write: %s\n", error.c_str());
-            goto finalize_multi_package_session;
-        }
-
-        copy_to_file(local_fd.get(), remote_fd.get());
-        read_status_line(remote_fd.get(), buf, sizeof(buf));
-
-        if (strncmp("Success", buf, 7)) {
-            fprintf(stderr, "adb: failed to write %s\n", file);
-            fputs(buf, stderr);
-            goto finalize_multi_package_session;
-        }
-
         all_session_ids += android::base::StringPrintf(" %d", session_id);
     }
 
@@ -718,6 +722,7 @@
         fputs(buf, stderr);
     }
 
+    session_ids.push_back(parent_session_id);
     // try to abandon all remaining sessions
     for (std::size_t i = 0; i < session_ids.size(); i++) {
         service = android::base::StringPrintf("%s install-abandon %d", install_cmd.c_str(),
diff --git a/adb/client/commandline.cpp b/adb/client/commandline.cpp
index f70b480..3286959 100644
--- a/adb/client/commandline.cpp
+++ b/adb/client/commandline.cpp
@@ -190,8 +190,8 @@
         "scripting:\n"
         " wait-for[-TRANSPORT]-STATE\n"
         "     wait for device to be in the given state\n"
-        "     State: device, recovery, sideload, or bootloader\n"
-        "     Transport: usb, local, or any [default=any]\n"
+        "     STATE: device, recovery, sideload, bootloader, or disconnect\n"
+        "     TRANSPORT: usb, local, or any [default=any]\n"
         " get-state                print offline | bootloader | device\n"
         " get-serialno             print <serial-number>\n"
         " get-devpath              print <device-path>\n"
@@ -1031,10 +1031,11 @@
     }
 
     if (components[3] != "any" && components[3] != "bootloader" && components[3] != "device" &&
-        components[3] != "recovery" && components[3] != "sideload") {
+        components[3] != "recovery" && components[3] != "sideload" &&
+        components[3] != "disconnect") {
         fprintf(stderr,
                 "adb: unknown state %s; "
-                "expected 'any', 'bootloader', 'device', 'recovery', or 'sideload'\n",
+                "expected 'any', 'bootloader', 'device', 'recovery', 'sideload', or 'disconnect'\n",
                 components[3].c_str());
         return false;
     }
@@ -1046,7 +1047,8 @@
 static bool adb_root(const char* command) {
     std::string error;
 
-    unique_fd fd(adb_connect(android::base::StringPrintf("%s:", command), &error));
+    TransportId transport_id;
+    unique_fd fd(adb_connect(&transport_id, android::base::StringPrintf("%s:", command), &error));
     if (fd < 0) {
         fprintf(stderr, "adb: unable to connect for %s: %s\n", command, error.c_str());
         return false;
@@ -1079,9 +1081,9 @@
         return true;
     }
 
-    // Give adbd some time to kill itself and come back up.
-    // We can't use wait-for-device because devices (e.g. adb over network) might not come back.
-    std::this_thread::sleep_for(3s);
+    // Wait for the device to go away.
+    adb_set_transport(kTransportAny, nullptr, transport_id);
+    wait_for_device("wait-for-disconnect");
     return true;
 }
 
diff --git a/adb/daemon/abb.cpp b/adb/daemon/abb.cpp
index d949dd1..eeac41a 100644
--- a/adb/daemon/abb.cpp
+++ b/adb/daemon/abb.cpp
@@ -14,15 +14,15 @@
  * limitations under the License.
  */
 
-#include "adb.h"
-#include "adb_io.h"
-#include "shell_service.h"
-
-#include "cmd.h"
-
 #include <sys/wait.h>
 
 #include <android-base/cmsg.h>
+#include <cmd.h>
+
+#include "adb.h"
+#include "adb_io.h"
+#include "adb_utils.h"
+#include "shell_service.h"
 
 namespace {
 
@@ -85,7 +85,17 @@
             break;
         }
 
-        unique_fd result = StartCommandInProcess(std::move(data), &execCmd);
+        std::string_view name = data;
+        auto protocol = SubprocessProtocol::kShell;
+        if (ConsumePrefix(&name, "abb:")) {
+            protocol = SubprocessProtocol::kShell;
+        } else if (ConsumePrefix(&name, "abb_exec:")) {
+            protocol = SubprocessProtocol::kNone;
+        } else {
+            LOG(FATAL) << "Unknown command prefix for abb: " << data;
+        }
+
+        unique_fd result = StartCommandInProcess(std::string(name), &execCmd, protocol);
         if (android::base::SendFileDescriptors(fd, "", 1, result.get()) != 1) {
             PLOG(ERROR) << "Failed to send an inprocess fd for command: " << data;
             break;
diff --git a/adb/daemon/abb_service.cpp b/adb/daemon/abb_service.cpp
index d32bf52..a435279 100644
--- a/adb/daemon/abb_service.cpp
+++ b/adb/daemon/abb_service.cpp
@@ -86,6 +86,6 @@
 
 }  // namespace
 
-unique_fd execute_binder_command(std::string_view command) {
+unique_fd execute_abb_command(std::string_view command) {
     return abbp->sendCommand(command);
 }
diff --git a/adb/daemon/remount_service.cpp b/adb/daemon/remount_service.cpp
index 5e6d416..7999ddc 100644
--- a/adb/daemon/remount_service.cpp
+++ b/adb/daemon/remount_service.cpp
@@ -14,339 +14,81 @@
  * limitations under the License.
  */
 
-#define TRACE_TAG ADB
-
-#include "sysdeps.h"
-
 #include <errno.h>
 #include <fcntl.h>
-#include <mntent.h>
-#include <spawn.h>
-#include <stdio.h>
-#include <stdlib.h>
 #include <string.h>
-#include <sys/mount.h>
-#include <sys/statvfs.h>
-#include <sys/vfs.h>
+#include <sys/types.h>
+#include <sys/wait.h>
 #include <unistd.h>
 
-#include <memory>
-#include <set>
 #include <string>
-#include <vector>
-
-#include <android-base/file.h>
-#include <android-base/properties.h>
-#include <bootloader_message/bootloader_message.h>
-#include <cutils/android_reboot.h>
-#include <fs_mgr.h>
-#include <fs_mgr_overlayfs.h>
 
 #include "adb.h"
 #include "adb_io.h"
 #include "adb_unique_fd.h"
-#include "adb_utils.h"
-#include "set_verity_enable_state_service.h"
-
-using android::base::Realpath;
-using android::fs_mgr::Fstab;
-using android::fs_mgr::ReadDefaultFstab;
-
-// Returns the last device used to mount a directory in /proc/mounts.
-// This will find overlayfs entry where upperdir=lowerdir, to make sure
-// remount is associated with the correct directory.
-static std::string find_proc_mount(const char* dir) {
-    std::unique_ptr<FILE, int(*)(FILE*)> fp(setmntent("/proc/mounts", "r"), endmntent);
-    std::string mnt_fsname;
-    if (!fp) return mnt_fsname;
-
-    // dir might be a symlink, e.g., /product -> /system/product in GSI.
-    std::string canonical_path;
-    if (!Realpath(dir, &canonical_path)) {
-        PLOG(ERROR) << "Realpath failed: " << dir;
-    }
-
-    mntent* e;
-    while ((e = getmntent(fp.get())) != nullptr) {
-        if (canonical_path == e->mnt_dir) {
-            mnt_fsname = e->mnt_fsname;
-        }
-    }
-    return mnt_fsname;
-}
-
-// Returns the device used to mount a directory in the fstab.
-static std::string find_fstab_mount(const char* dir) {
-    Fstab fstab;
-    if (!ReadDefaultFstab(&fstab)) {
-        return "";
-    }
-
-    auto entry = std::find_if(fstab.begin(), fstab.end(),
-                              [&dir](const auto& entry) { return entry.mount_point == dir; });
-    if (entry == fstab.end()) {
-        return "";
-    }
-    if (entry->fs_mgr_flags.logical) {
-        fs_mgr_update_logical_partition(&(*entry));
-    }
-    return entry->blk_device;
-}
-
-// The proc entry for / is full of lies, so check fstab instead.
-// /proc/mounts lists rootfs and /dev/root, neither of which is what we want.
-static std::string find_mount(const char* dir, bool is_root) {
-    if (is_root) {
-        return find_fstab_mount(dir);
-    } else {
-        return find_proc_mount(dir);
-    }
-}
-
-bool dev_is_overlayfs(const std::string& dev) {
-    return (dev == "overlay") || (dev == "overlayfs");
-}
-
-bool make_block_device_writable(const std::string& dev) {
-    if (dev_is_overlayfs(dev)) return true;
-    int fd = unix_open(dev, O_RDONLY | O_CLOEXEC);
-    if (fd == -1) {
-        return false;
-    }
-
-    int OFF = 0;
-    bool result = (ioctl(fd, BLKROSET, &OFF) != -1);
-    unix_close(fd);
-    return result;
-}
-
-static bool can_unshare_blocks(int fd, const char* dev) {
-    const char* E2FSCK_BIN = "/system/bin/e2fsck";
-    if (access(E2FSCK_BIN, X_OK)) {
-        WriteFdFmt(fd, "e2fsck is not available, cannot undo deduplication on %s\n", dev);
-        return false;
-    }
-
-    pid_t child;
-    char* env[] = {nullptr};
-    const char* argv[] = {E2FSCK_BIN, "-n", "-E", "unshare_blocks", dev, nullptr};
-    if (posix_spawn(&child, E2FSCK_BIN, nullptr, nullptr, const_cast<char**>(argv), env)) {
-        WriteFdFmt(fd, "failed to e2fsck to check deduplication: %s\n", strerror(errno));
-        return false;
-    }
-    int status = 0;
-    int ret = TEMP_FAILURE_RETRY(waitpid(child, &status, 0));
-    if (ret < 0) {
-        WriteFdFmt(fd, "failed to get e2fsck status: %s\n", strerror(errno));
-        return false;
-    }
-    if (!WIFEXITED(status)) {
-        WriteFdFmt(fd, "e2fsck exited abnormally with status %d\n", status);
-        return false;
-    }
-    int rc = WEXITSTATUS(status);
-    if (rc != 0) {
-        WriteFdFmt(fd,
-                   "%s is deduplicated, and an e2fsck check failed. It might not "
-                   "have enough free-space to be remounted as writable.\n",
-                   dev);
-        return false;
-    }
-    return true;
-}
-
-static unsigned long get_mount_flags(int fd, const char* dir) {
-    struct statvfs st_vfs;
-    if (statvfs(dir, &st_vfs) == -1) {
-        // Even though we could not get the original mount flags, assume that
-        // the mount was originally read-only.
-        WriteFdFmt(fd, "statvfs of the %s mount failed: %s.\n", dir, strerror(errno));
-        return MS_RDONLY;
-    }
-    return st_vfs.f_flag;
-}
-
-static bool remount_partition(int fd, const char* dir) {
-    if (!directory_exists(dir)) {
-        return true;
-    }
-    bool is_root = strcmp(dir, "/") == 0;
-    if (is_root && dev_is_overlayfs(find_mount("/system", false))) {
-        dir = "/system";
-        is_root = false;
-    }
-    std::string dev = find_mount(dir, is_root);
-    if (is_root && dev.empty()) {
-        // The fstab entry will be /system if the device switched roots during
-        // first-stage init.
-        dev = find_mount("/system", true);
-    }
-    // Even if the device for the root is not found, we still try to remount it
-    // as rw. This typically only happens when running Android in a container:
-    // the root will almost always be in a loop device, which is dynamic, so
-    // it's not convenient to put in the fstab.
-    if (dev.empty() && !is_root) {
-        return true;
-    }
-    if (!dev.empty() && !make_block_device_writable(dev)) {
-        WriteFdFmt(fd, "remount of %s failed; couldn't make block device %s writable: %s\n",
-                   dir, dev.c_str(), strerror(errno));
-        return false;
-    }
-
-    unsigned long remount_flags = get_mount_flags(fd, dir);
-    remount_flags &= ~MS_RDONLY;
-    remount_flags |= MS_REMOUNT;
-
-    if (mount(dev.c_str(), dir, "none", remount_flags | MS_BIND, nullptr) == -1) {
-        // This is useful for cases where the superblock is already marked as
-        // read-write, but the mount itself is read-only, such as containers
-        // where the remount with just MS_REMOUNT is forbidden by the kernel.
-        WriteFdFmt(fd, "remount of the %s mount failed: %s.\n", dir, strerror(errno));
-        return false;
-    }
-    if (mount(dev.c_str(), dir, "none", MS_REMOUNT, nullptr) == -1) {
-        WriteFdFmt(fd, "remount of the %s superblock failed: %s\n", dir, strerror(errno));
-        return false;
-    }
-    return true;
-}
-
-static void reboot_for_remount(int fd, bool need_fsck) {
-    std::string reboot_cmd = "reboot";
-    if (need_fsck) {
-        const std::vector<std::string> options = {"--fsck_unshare_blocks"};
-        std::string err;
-        if (!write_bootloader_message(options, &err)) {
-            WriteFdFmt(fd, "Failed to set bootloader message: %s\n", err.c_str());
-            return;
-        }
-
-        WriteFdExactly(fd,
-                       "The device will now reboot to recovery and attempt "
-                       "un-deduplication.\n");
-        reboot_cmd = "reboot,recovery";
-    }
-
-    sync();
-    android::base::SetProperty(ANDROID_RB_PROPERTY, reboot_cmd.c_str());
-}
-
-static void try_unmount_bionic(int fd) {
-    static constexpr const char* kBionic = "/bionic";
-    struct statfs buf;
-    if (statfs(kBionic, &buf) == -1) {
-        WriteFdFmt(fd, "statfs of the %s mount failed: %s.\n", kBionic, strerror(errno));
-        return;
-    }
-    if (buf.f_flags & ST_RDONLY) {
-        // /bionic is on a read-only partition; can happen for
-        // non-system-as-root-devices. Don' try to unmount.
-        return;
-    }
-    // Success/Fail of the actual remount will be reported by the function.
-    remount_partition(fd, kBionic);
-    return;
-}
 
 void remount_service(unique_fd fd, const std::string& cmd) {
-    bool user_requested_reboot = cmd == "-R";
+    static constexpr char remount_cmd[] = "/system/bin/remount";
+    static constexpr char remount_failed[] = "remount failed\n";
 
     if (getuid() != 0) {
         WriteFdExactly(fd.get(), "Not running as root. Try \"adb root\" first.\n");
+        WriteFdExactly(fd.get(), remount_failed);
         return;
     }
 
-    bool system_verified = !(android::base::GetProperty("partition.system.verified", "").empty());
-    bool vendor_verified = !(android::base::GetProperty("partition.vendor.verified", "").empty());
-
-    std::vector<std::string> partitions{"/",        "/odm",   "/oem", "/product_services",
-                                        "/product", "/vendor"};
-
-    if (system_verified || vendor_verified) {
-        // Disable verity automatically (reboot will be required).
-        set_verity_enabled_state_service(unique_fd(dup(fd.get())), false);
-
-        // If overlayfs is not supported, we try and remount or set up
-        // un-deduplication. If it is supported, we can go ahead and wait for
-        // a reboot.
-        if (fs_mgr_overlayfs_valid() != OverlayfsValidResult::kNotSupported) {
-            if (user_requested_reboot) {
-                if (android::base::SetProperty(ANDROID_RB_PROPERTY, "reboot")) {
-                    WriteFdExactly(fd.get(), "rebooting device\n");
-                } else {
-                    WriteFdExactly(fd.get(), "reboot failed\n");
-                }
-            }
-            return;
-        }
-    } else if (fs_mgr_overlayfs_setup()) {
-        // If we can use overlayfs, lets get it in place first before we
-        // struggle with determining deduplication operations.
-        Fstab fstab;
-        if (ReadDefaultFstab(&fstab) && fs_mgr_overlayfs_mount_all(&fstab)) {
-            WriteFdExactly(fd.get(), "overlayfs mounted\n");
-        }
-    }
-
-    // If overlayfs is supported, we don't bother trying to un-deduplicate
-    // partitions.
-    std::set<std::string> dedup;
-    if (fs_mgr_overlayfs_valid() == OverlayfsValidResult::kNotSupported) {
-        // Find partitions that are deduplicated, and can be un-deduplicated.
-        for (const auto& part : partitions) {
-            auto partition = part;
-            if ((part == "/") && !find_mount("/system", false).empty()) partition = "/system";
-            std::string dev = find_mount(partition.c_str(), partition == "/");
-            if (dev.empty() || !fs_mgr_has_shared_blocks(partition, dev)) {
-                continue;
-            }
-            if (can_unshare_blocks(fd.get(), dev.c_str())) {
-                dedup.emplace(partition);
-            }
-        }
-
-        // Reboot now if the user requested it (and an operation needs a reboot).
-        if (user_requested_reboot) {
-            if (!dedup.empty()) {
-                reboot_for_remount(fd.get(), !dedup.empty());
-                return;
-            }
-            WriteFdExactly(fd.get(), "No reboot needed, skipping -R.\n");
-        }
-    }
-
-    bool success = true;
-    for (const auto& partition : partitions) {
-        // Don't try to remount partitions that need an fsck in recovery.
-        if (dedup.count(partition)) {
-            continue;
-        }
-        success &= remount_partition(fd.get(), partition.c_str());
-    }
-
-    if (!dedup.empty()) {
-        WriteFdExactly(fd.get(),
-                       "The following partitions are deduplicated and cannot "
-                       "yet be remounted:\n");
-        for (const std::string& name : dedup) {
-            WriteFdFmt(fd.get(), "  %s\n", name.c_str());
-        }
-
-        WriteFdExactly(fd.get(),
-                       "To reboot and un-deduplicate the listed partitions, "
-                       "please retry with adb remount -R.\n");
-        if (system_verified || vendor_verified) {
-            WriteFdExactly(fd.get(), "Note: verity will be automatically disabled after reboot.\n");
-        }
+    auto pid = vfork();
+    if (pid < 0) {
+        WriteFdFmt(fd.get(), "Failed to fork to %s: %s\n", remount_cmd, strerror(errno));
+        WriteFdExactly(fd.get(), remount_failed);
         return;
     }
 
-    try_unmount_bionic(fd.get());
+    if (pid == 0) {
+        // child side of the fork
+        fcntl(fd.get(), F_SETFD, 0);
+        dup2(fd.get(), STDIN_FILENO);
+        dup2(fd.get(), STDOUT_FILENO);
+        dup2(fd.get(), STDERR_FILENO);
 
-    if (!success) {
-        WriteFdExactly(fd.get(), "remount failed\n");
-    } else {
-        WriteFdExactly(fd.get(), "remount succeeded\n");
+        execl(remount_cmd, remount_cmd, cmd.empty() ? nullptr : cmd.c_str(), nullptr);
+        _exit(-errno ?: 42);
     }
+
+    int wstatus = 0;
+    auto ret = waitpid(pid, &wstatus, 0);
+
+    if (ret == -1) {
+        WriteFdFmt(fd.get(), "Failed to wait for %s: %s\n", remount_cmd, strerror(errno));
+        goto err;
+    }
+
+    if (ret != pid) {
+        WriteFdFmt(fd.get(), "pid %d and waitpid return %d do not match for %s\n",
+                   static_cast<int>(pid), static_cast<int>(ret), remount_cmd);
+        goto err;
+    }
+
+    if (WIFSIGNALED(wstatus)) {
+        WriteFdFmt(fd.get(), "%s terminated with signal %s\n", remount_cmd,
+                   strsignal(WTERMSIG(wstatus)));
+        goto err;
+    }
+
+    if (!WIFEXITED(wstatus)) {
+        WriteFdFmt(fd.get(), "%s stopped with status 0x%x\n", remount_cmd, wstatus);
+        goto err;
+    }
+
+    if (WEXITSTATUS(wstatus)) {
+        WriteFdFmt(fd.get(), "%s exited with status %d\n", remount_cmd,
+                   static_cast<signed char>(WEXITSTATUS(wstatus)));
+        goto err;
+    }
+
+    WriteFdExactly(fd.get(), "remount succeeded\n");
+    return;
+
+err:
+    WriteFdExactly(fd.get(), remount_failed);
 }
diff --git a/adb/daemon/remount_service.h b/adb/daemon/remount_service.h
index c847403..522a5da 100644
--- a/adb/daemon/remount_service.h
+++ b/adb/daemon/remount_service.h
@@ -21,6 +21,5 @@
 #include "adb_unique_fd.h"
 
 #if defined(__ANDROID__)
-bool make_block_device_writable(const std::string&);
 void remount_service(unique_fd, const std::string&);
 #endif
diff --git a/adb/daemon/services.cpp b/adb/daemon/services.cpp
index d1f0345..b0cc450 100644
--- a/adb/daemon/services.cpp
+++ b/adb/daemon/services.cpp
@@ -223,17 +223,15 @@
         return create_jdwp_service_socket();
     } else if (name == "track-jdwp") {
         return create_jdwp_tracker_service_socket();
-    } else if (name.starts_with("sink:")) {
-        name.remove_prefix(strlen("sink:"));
+    } else if (ConsumePrefix(&name, "sink:")) {
         uint64_t byte_count = 0;
-        if (!android::base::ParseUint(name.data(), &byte_count)) {
+        if (!ParseUint(&byte_count, name)) {
             return nullptr;
         }
         return new SinkSocket(byte_count);
-    } else if (name.starts_with("source:")) {
-        name.remove_prefix(strlen("source:"));
+    } else if (ConsumePrefix(&name, "source:")) {
         uint64_t byte_count = 0;
-        if (!android::base::ParseUint(name.data(), &byte_count)) {
+        if (!ParseUint(&byte_count, name)) {
             return nullptr;
         }
         return new SourceSocket(byte_count);
@@ -244,29 +242,27 @@
 
 unique_fd daemon_service_to_fd(std::string_view name, atransport* transport) {
 #if defined(__ANDROID__) && !defined(__ANDROID_RECOVERY__)
-    if (name.starts_with("abb:")) {
-        name.remove_prefix(strlen("abb:"));
-        return execute_binder_command(name);
+    if (name.starts_with("abb:") || name.starts_with("abb_exec:")) {
+        return execute_abb_command(name);
     }
 #endif
 
 #if defined(__ANDROID__)
     if (name.starts_with("framebuffer:")) {
         return create_service_thread("fb", framebuffer_service);
-    } else if (name.starts_with("remount:")) {
-        std::string arg(name.begin() + strlen("remount:"), name.end());
+    } else if (ConsumePrefix(&name, "remount:")) {
+        std::string arg(name);
         return create_service_thread("remount",
                                      std::bind(remount_service, std::placeholders::_1, arg));
-    } else if (name.starts_with("reboot:")) {
-        std::string arg(name.begin() + strlen("reboot:"), name.end());
+    } else if (ConsumePrefix(&name, "reboot:")) {
+        std::string arg(name);
         return create_service_thread("reboot",
                                      std::bind(reboot_service, std::placeholders::_1, arg));
     } else if (name.starts_with("root:")) {
         return create_service_thread("root", restart_root_service);
     } else if (name.starts_with("unroot:")) {
         return create_service_thread("unroot", restart_unroot_service);
-    } else if (name.starts_with("backup:")) {
-        name.remove_prefix(strlen("backup:"));
+    } else if (ConsumePrefix(&name, "backup:")) {
         std::string cmd = "/system/bin/bu backup ";
         cmd += name;
         return StartSubprocess(cmd, nullptr, SubprocessType::kRaw, SubprocessProtocol::kNone);
@@ -279,8 +275,7 @@
     } else if (name.starts_with("enable-verity:")) {
         return create_service_thread("verity-off", std::bind(set_verity_enabled_state_service,
                                                              std::placeholders::_1, true));
-    } else if (name.starts_with("tcpip:")) {
-        name.remove_prefix(strlen("tcpip:"));
+    } else if (ConsumePrefix(&name, "tcpip:")) {
         std::string str(name);
 
         int port;
@@ -294,24 +289,22 @@
     }
 #endif
 
-    if (name.starts_with("dev:")) {
-        name.remove_prefix(strlen("dev:"));
+    if (ConsumePrefix(&name, "dev:")) {
         return unique_fd{unix_open(name, O_RDWR | O_CLOEXEC)};
-    } else if (name.starts_with("jdwp:")) {
-        name.remove_prefix(strlen("jdwp:"));
-        std::string str(name);
-        return create_jdwp_connection_fd(atoi(str.c_str()));
-    } else if (name.starts_with("shell")) {
-        name.remove_prefix(strlen("shell"));
+    } else if (ConsumePrefix(&name, "jdwp:")) {
+        pid_t pid;
+        if (!ParseUint(&pid, name)) {
+            return unique_fd{};
+        }
+        return create_jdwp_connection_fd(pid);
+    } else if (ConsumePrefix(&name, "shell")) {
         return ShellService(name, transport);
-    } else if (name.starts_with("exec:")) {
-        name.remove_prefix(strlen("exec:"));
+    } else if (ConsumePrefix(&name, "exec:")) {
         return StartSubprocess(std::string(name), nullptr, SubprocessType::kRaw,
                                SubprocessProtocol::kNone);
     } else if (name.starts_with("sync:")) {
         return create_service_thread("sync", file_sync_service);
-    } else if (name.starts_with("reverse:")) {
-        name.remove_prefix(strlen("reverse:"));
+    } else if (ConsumePrefix(&name, "reverse:")) {
         return reverse_service(name, transport);
     } else if (name == "reconnect") {
         return create_service_thread(
diff --git a/adb/daemon/set_verity_enable_state_service.cpp b/adb/daemon/set_verity_enable_state_service.cpp
index 92851c0..658261e 100644
--- a/adb/daemon/set_verity_enable_state_service.cpp
+++ b/adb/daemon/set_verity_enable_state_service.cpp
@@ -25,6 +25,7 @@
 #include <libavb_user/libavb_user.h>
 #include <stdarg.h>
 #include <stdio.h>
+#include <sys/mount.h>
 #include <sys/stat.h>
 
 #include <android-base/properties.h>
@@ -37,7 +38,6 @@
 #include "adb.h"
 #include "adb_io.h"
 #include "adb_unique_fd.h"
-#include "remount_service.h"
 
 #include "fec/io.h"
 
@@ -51,6 +51,18 @@
     if (getuid() != 0) WriteFdExactly(fd, "Maybe run adb root?\n");
 }
 
+static bool make_block_device_writable(const std::string& dev) {
+    int fd = unix_open(dev, O_RDONLY | O_CLOEXEC);
+    if (fd == -1) {
+        return false;
+    }
+
+    int OFF = 0;
+    bool result = (ioctl(fd, BLKROSET, &OFF) != -1);
+    unix_close(fd);
+    return result;
+}
+
 /* Turn verity on/off */
 static bool set_verity_enabled_state(int fd, const char* block_device, const char* mount_point,
                                      bool enable) {
diff --git a/adb/daemon/shell_service.cpp b/adb/daemon/shell_service.cpp
index 0794bcd..e9d9c63 100644
--- a/adb/daemon/shell_service.cpp
+++ b/adb/daemon/shell_service.cpp
@@ -170,6 +170,8 @@
     // Opens the file at |pts_name|.
     int OpenPtyChildFd(const char* pts_name, unique_fd* error_sfd);
 
+    bool ConnectProtocolEndpoints(std::string* _Nonnull error);
+
     static void ThreadHandler(void* userdata);
     void PassDataStreams();
     void WaitForExit();
@@ -383,42 +385,9 @@
     }
 
     D("subprocess parent: exec completed");
-    if (protocol_ == SubprocessProtocol::kNone) {
-        // No protocol: all streams pass through the stdinout FD and hook
-        // directly into the local socket for raw data transfer.
-        local_socket_sfd_.reset(stdinout_sfd_.release());
-    } else {
-        // Shell protocol: create another socketpair to intercept data.
-        if (!CreateSocketpair(&protocol_sfd_, &local_socket_sfd_)) {
-            *error = android::base::StringPrintf(
-                "failed to create socketpair to intercept data: %s", strerror(errno));
-            kill(pid_, SIGKILL);
-            return false;
-        }
-        D("protocol FD = %d", protocol_sfd_.get());
-
-        input_ = std::make_unique<ShellProtocol>(protocol_sfd_);
-        output_ = std::make_unique<ShellProtocol>(protocol_sfd_);
-        if (!input_ || !output_) {
-            *error = "failed to allocate shell protocol objects";
-            kill(pid_, SIGKILL);
-            return false;
-        }
-
-        // Don't let reads/writes to the subprocess block our thread. This isn't
-        // likely but could happen under unusual circumstances, such as if we
-        // write a ton of data to stdin but the subprocess never reads it and
-        // the pipe fills up.
-        for (int fd : {stdinout_sfd_.get(), stderr_sfd_.get()}) {
-            if (fd >= 0) {
-                if (!set_file_block_mode(fd, false)) {
-                    *error = android::base::StringPrintf(
-                        "failed to set non-blocking mode for fd %d", fd);
-                    kill(pid_, SIGKILL);
-                    return false;
-                }
-            }
-        }
+    if (!ConnectProtocolEndpoints(error)) {
+        kill(pid_, SIGKILL);
+        return false;
     }
 
     D("subprocess parent: completed");
@@ -429,7 +398,6 @@
     unique_fd child_stdinout_sfd, child_stderr_sfd;
 
     CHECK(type_ == SubprocessType::kRaw);
-    CHECK(protocol_ == SubprocessProtocol::kShell);
 
     __android_log_security_bswrite(SEC_TAG_ADB_SHELL_CMD, command_.c_str());
 
@@ -448,34 +416,9 @@
     D("execinprocess: stdin/stdout FD = %d, stderr FD = %d", stdinout_sfd_.get(),
       stderr_sfd_.get());
 
-    // Required for shell protocol: create another socketpair to intercept data.
-    if (!CreateSocketpair(&protocol_sfd_, &local_socket_sfd_)) {
-        *error = android::base::StringPrintf("failed to create socketpair to intercept data: %s",
-                                             strerror(errno));
+    if (!ConnectProtocolEndpoints(error)) {
         return false;
     }
-    D("protocol FD = %d", protocol_sfd_.get());
-
-    input_ = std::make_unique<ShellProtocol>(protocol_sfd_);
-    output_ = std::make_unique<ShellProtocol>(protocol_sfd_);
-    if (!input_ || !output_) {
-        *error = "failed to allocate shell protocol objects";
-        return false;
-    }
-
-    // Don't let reads/writes to the subprocess block our thread. This isn't
-    // likely but could happen under unusual circumstances, such as if we
-    // write a ton of data to stdin but the subprocess never reads it and
-    // the pipe fills up.
-    for (int fd : {stdinout_sfd_.get(), stderr_sfd_.get()}) {
-        if (fd >= 0) {
-            if (!set_file_block_mode(fd, false)) {
-                *error = android::base::StringPrintf("failed to set non-blocking mode for fd %d",
-                                                     fd);
-                return false;
-            }
-        }
-    }
 
     std::thread([inout_sfd = std::move(child_stdinout_sfd), err_sfd = std::move(child_stderr_sfd),
                  command = std::move(command),
@@ -486,6 +429,45 @@
     return true;
 }
 
+bool Subprocess::ConnectProtocolEndpoints(std::string* _Nonnull error) {
+    if (protocol_ == SubprocessProtocol::kNone) {
+        // No protocol: all streams pass through the stdinout FD and hook
+        // directly into the local socket for raw data transfer.
+        local_socket_sfd_.reset(stdinout_sfd_.release());
+    } else {
+        // Required for shell protocol: create another socketpair to intercept data.
+        if (!CreateSocketpair(&protocol_sfd_, &local_socket_sfd_)) {
+            *error = android::base::StringPrintf(
+                    "failed to create socketpair to intercept data: %s", strerror(errno));
+            return false;
+        }
+        D("protocol FD = %d", protocol_sfd_.get());
+
+        input_ = std::make_unique<ShellProtocol>(protocol_sfd_);
+        output_ = std::make_unique<ShellProtocol>(protocol_sfd_);
+        if (!input_ || !output_) {
+            *error = "failed to allocate shell protocol objects";
+            return false;
+        }
+
+        // Don't let reads/writes to the subprocess block our thread. This isn't
+        // likely but could happen under unusual circumstances, such as if we
+        // write a ton of data to stdin but the subprocess never reads it and
+        // the pipe fills up.
+        for (int fd : {stdinout_sfd_.get(), stderr_sfd_.get()}) {
+            if (fd >= 0) {
+                if (!set_file_block_mode(fd, false)) {
+                    *error = android::base::StringPrintf(
+                            "failed to set non-blocking mode for fd %d", fd);
+                    return false;
+                }
+            }
+        }
+    }
+
+    return true;
+}
+
 bool Subprocess::StartThread(std::unique_ptr<Subprocess> subprocess, std::string* error) {
     Subprocess* raw = subprocess.release();
     std::thread(ThreadHandler, raw).detach();
@@ -863,12 +845,11 @@
     return local_socket;
 }
 
-unique_fd StartCommandInProcess(std::string name, Command command) {
+unique_fd StartCommandInProcess(std::string name, Command command, SubprocessProtocol protocol) {
     LOG(INFO) << "StartCommandInProcess(" << dump_hex(name.data(), name.size()) << ")";
 
     constexpr auto terminal_type = "";
     constexpr auto type = SubprocessType::kRaw;
-    constexpr auto protocol = SubprocessProtocol::kShell;
     constexpr auto make_pty_raw = false;
 
     auto subprocess = std::make_unique<Subprocess>(std::move(name), terminal_type, type, protocol,
diff --git a/adb/daemon/shell_service.h b/adb/daemon/shell_service.h
index fc66377..3abd958 100644
--- a/adb/daemon/shell_service.h
+++ b/adb/daemon/shell_service.h
@@ -49,7 +49,7 @@
 //
 // Returns an open FD connected to the thread or -1 on failure.
 using Command = int(std::string_view args, int in, int out, int err);
-unique_fd StartCommandInProcess(std::string name, Command command);
+unique_fd StartCommandInProcess(std::string name, Command command, SubprocessProtocol protocol);
 
 // Create a pipe containing the error.
 unique_fd ReportError(SubprocessProtocol protocol, const std::string& message);
diff --git a/adb/daemon/usb.cpp b/adb/daemon/usb.cpp
index f0e2861..598f2cd 100644
--- a/adb/daemon/usb.cpp
+++ b/adb/daemon/usb.cpp
@@ -29,6 +29,7 @@
 #include <linux/usb/functionfs.h>
 #include <sys/eventfd.h>
 
+#include <algorithm>
 #include <array>
 #include <future>
 #include <memory>
@@ -56,10 +57,11 @@
 // We can't find out whether we have support for AIO on ffs endpoints until we submit a read.
 static std::optional<bool> gFfsAioSupported;
 
-static constexpr size_t kUsbReadQueueDepth = 16;
-static constexpr size_t kUsbReadSize = 16384;
+static constexpr size_t kUsbReadQueueDepth = 32;
+static constexpr size_t kUsbReadSize = 8 * PAGE_SIZE;
 
-static constexpr size_t kUsbWriteQueueDepth = 16;
+static constexpr size_t kUsbWriteQueueDepth = 32;
+static constexpr size_t kUsbWriteSize = 8 * PAGE_SIZE;
 
 static const char* to_string(enum usb_functionfs_event_type type) {
     switch (type) {
@@ -115,7 +117,7 @@
 struct IoBlock {
     bool pending;
     struct iocb control;
-    Block payload;
+    std::shared_ptr<Block> payload;
 
     TransferId id() const { return TransferId::from_value(control.aio_data); }
 };
@@ -207,8 +209,20 @@
         std::lock_guard<std::mutex> lock(write_mutex_);
         write_requests_.push_back(CreateWriteBlock(std::move(header), next_write_id_++));
         if (!packet->payload.empty()) {
-            write_requests_.push_back(
-                    CreateWriteBlock(std::move(packet->payload), next_write_id_++));
+            // The kernel attempts to allocate a contiguous block of memory for each write,
+            // which can fail if the write is large and the kernel heap is fragmented.
+            // Split large writes into smaller chunks to avoid this.
+            std::shared_ptr<Block> payload = std::make_shared<Block>(std::move(packet->payload));
+            size_t offset = 0;
+            size_t len = payload->size();
+
+            while (len > 0) {
+                size_t write_size = std::min(kUsbWriteSize, len);
+                write_requests_.push_back(
+                        CreateWriteBlock(payload, offset, write_size, next_write_id_++));
+                len -= write_size;
+                offset += write_size;
+            }
         }
         SubmitWrites();
         return true;
@@ -246,7 +260,6 @@
         // until it dies, and then report failure to the transport via HandleError, which will
         // eventually result in the transport being destroyed, which will result in UsbFfsConnection
         // being destroyed, which unblocks the open thread and restarts this entire process.
-        static constexpr int kInterruptionSignal = SIGUSR1;
         static std::once_flag handler_once;
         std::call_once(handler_once, []() { signal(kInterruptionSignal, [](int) {}); });
 
@@ -272,6 +285,7 @@
                 } else if (rc == 0) {
                     // Something in the kernel presumably went wrong.
                     // Close our endpoints, wait for a bit, and then try again.
+                    StopWorker();
                     aio_context_.reset();
                     read_fd_.reset();
                     write_fd_.reset();
@@ -297,7 +311,7 @@
 
                 switch (event.type) {
                     case FUNCTIONFS_BIND:
-                        CHECK(!started) << "received FUNCTIONFS_ENABLE while already bound?";
+                        CHECK(!bound) << "received FUNCTIONFS_BIND while already bound?";
                         bound = true;
                         break;
 
@@ -313,28 +327,7 @@
                 }
             }
 
-            pthread_t worker_thread_handle = worker_thread_.native_handle();
-            while (true) {
-                int rc = pthread_kill(worker_thread_handle, kInterruptionSignal);
-                if (rc != 0) {
-                    LOG(ERROR) << "failed to send interruption signal to worker: " << strerror(rc);
-                    break;
-                }
-
-                std::this_thread::sleep_for(100ms);
-
-                rc = pthread_kill(worker_thread_handle, 0);
-                if (rc == 0) {
-                    continue;
-                } else if (rc == ESRCH) {
-                    break;
-                } else {
-                    LOG(ERROR) << "failed to send interruption signal to worker: " << strerror(rc);
-                }
-            }
-
-            worker_thread_.join();
-
+            StopWorker();
             aio_context_.reset();
             read_fd_.reset();
             write_fd_.reset();
@@ -365,12 +358,36 @@
         });
     }
 
+    void StopWorker() {
+        pthread_t worker_thread_handle = worker_thread_.native_handle();
+        while (true) {
+            int rc = pthread_kill(worker_thread_handle, kInterruptionSignal);
+            if (rc != 0) {
+                LOG(ERROR) << "failed to send interruption signal to worker: " << strerror(rc);
+                break;
+            }
+
+            std::this_thread::sleep_for(100ms);
+
+            rc = pthread_kill(worker_thread_handle, 0);
+            if (rc == 0) {
+                continue;
+            } else if (rc == ESRCH) {
+                break;
+            } else {
+                LOG(ERROR) << "failed to send interruption signal to worker: " << strerror(rc);
+            }
+        }
+
+        worker_thread_.join();
+    }
+
     void PrepareReadBlock(IoBlock* block, uint64_t id) {
         block->pending = false;
-        block->payload.resize(kUsbReadSize);
+        block->payload = std::make_shared<Block>(kUsbReadSize);
         block->control.aio_data = static_cast<uint64_t>(TransferId::read(id));
-        block->control.aio_buf = reinterpret_cast<uintptr_t>(block->payload.data());
-        block->control.aio_nbytes = block->payload.size();
+        block->control.aio_buf = reinterpret_cast<uintptr_t>(block->payload->data());
+        block->control.aio_nbytes = block->payload->size();
     }
 
     IoBlock CreateReadBlock(uint64_t id) {
@@ -421,7 +438,7 @@
         uint64_t read_idx = id.id % kUsbReadQueueDepth;
         IoBlock* block = &read_requests_[read_idx];
         block->pending = false;
-        block->payload.resize(size);
+        block->payload->resize(size);
 
         // Notification for completed reads can be received out of order.
         if (block->id().id != needed_read_id_) {
@@ -442,16 +459,16 @@
     }
 
     void ProcessRead(IoBlock* block) {
-        if (!block->payload.empty()) {
+        if (!block->payload->empty()) {
             if (!incoming_header_.has_value()) {
-                CHECK_EQ(sizeof(amessage), block->payload.size());
+                CHECK_EQ(sizeof(amessage), block->payload->size());
                 amessage msg;
-                memcpy(&msg, block->payload.data(), sizeof(amessage));
+                memcpy(&msg, block->payload->data(), sizeof(amessage));
                 LOG(DEBUG) << "USB read:" << dump_header(&msg);
                 incoming_header_ = msg;
             } else {
                 size_t bytes_left = incoming_header_->data_length - incoming_payload_.size();
-                Block payload = std::move(block->payload);
+                Block payload = std::move(*block->payload);
                 CHECK_LE(payload.size(), bytes_left);
                 incoming_payload_.append(std::make_unique<Block>(std::move(payload)));
             }
@@ -506,7 +523,8 @@
         SubmitWrites();
     }
 
-    std::unique_ptr<IoBlock> CreateWriteBlock(Block payload, uint64_t id) {
+    std::unique_ptr<IoBlock> CreateWriteBlock(std::shared_ptr<Block> payload, size_t offset,
+                                              size_t len, uint64_t id) {
         auto block = std::make_unique<IoBlock>();
         block->payload = std::move(payload);
         block->control.aio_data = static_cast<uint64_t>(TransferId::write(id));
@@ -514,14 +532,20 @@
         block->control.aio_lio_opcode = IOCB_CMD_PWRITE;
         block->control.aio_reqprio = 0;
         block->control.aio_fildes = write_fd_.get();
-        block->control.aio_buf = reinterpret_cast<uintptr_t>(block->payload.data());
-        block->control.aio_nbytes = block->payload.size();
+        block->control.aio_buf = reinterpret_cast<uintptr_t>(block->payload->data() + offset);
+        block->control.aio_nbytes = len;
         block->control.aio_offset = 0;
         block->control.aio_flags = IOCB_FLAG_RESFD;
         block->control.aio_resfd = worker_event_fd_.get();
         return block;
     }
 
+    std::unique_ptr<IoBlock> CreateWriteBlock(Block payload, uint64_t id) {
+        std::shared_ptr<Block> block = std::make_shared<Block>(std::move(payload));
+        size_t len = block->size();
+        return CreateWriteBlock(std::move(block), 0, len, id);
+    }
+
     void SubmitWrites() REQUIRES(write_mutex_) {
         if (writes_submitted_ == kUsbWriteQueueDepth) {
             return;
@@ -594,6 +618,8 @@
     std::deque<std::unique_ptr<IoBlock>> write_requests_ GUARDED_BY(write_mutex_);
     size_t next_write_id_ GUARDED_BY(write_mutex_) = 0;
     size_t writes_submitted_ GUARDED_BY(write_mutex_) = 0;
+
+    static constexpr int kInterruptionSignal = SIGUSR1;
 };
 
 void usb_init_legacy();
diff --git a/adb/services.cpp b/adb/services.cpp
index 0061f0e..80f9f79 100644
--- a/adb/services.cpp
+++ b/adb/services.cpp
@@ -25,6 +25,7 @@
 #include <string.h>
 
 #include <thread>
+
 #include <android-base/stringprintf.h>
 #include <android-base/strings.h>
 #include <cutils/sockets.h>
@@ -63,11 +64,11 @@
         adb_setsockopt(s[0], SOL_SOCKET, SO_SNDBUF, &max_buf, sizeof(max_buf));
         adb_setsockopt(s[1], SOL_SOCKET, SO_SNDBUF, &max_buf, sizeof(max_buf));
     }
-#endif // !ADB_HOST
+#endif  // !ADB_HOST
 
     std::thread(service_bootstrap_func, service_name, func, unique_fd(s[1])).detach();
 
-    D("service thread started, %d:%d",s[0], s[1]);
+    D("service thread started, %d:%d", s[0], s[1]);
     return unique_fd(s[0]);
 }
 
@@ -108,12 +109,21 @@
         const char* serial = sinfo->serial.length() ? sinfo->serial.c_str() : nullptr;
         atransport* t = acquire_one_transport(sinfo->transport_type, serial, sinfo->transport_id,
                                               &is_ambiguous, &error);
-        if (t != nullptr && (sinfo->state == kCsAny || sinfo->state == t->GetConnectionState())) {
+        if (sinfo->state == kCsOffline) {
+            // wait-for-disconnect uses kCsOffline, we don't actually want to wait for 'offline'.
+            if (t == nullptr) {
+                SendOkay(fd);
+                break;
+            }
+        } else if (t != nullptr &&
+                   (sinfo->state == kCsAny || sinfo->state == t->GetConnectionState())) {
             SendOkay(fd);
             break;
-        } else if (!is_ambiguous) {
-            adb_pollfd pfd = {.fd = fd, .events = POLLIN };
-            int rc = adb_poll(&pfd, 1, 1000);
+        }
+
+        if (!is_ambiguous) {
+            adb_pollfd pfd = {.fd = fd, .events = POLLIN};
+            int rc = adb_poll(&pfd, 1, 100);
             if (rc < 0) {
                 SendFail(fd, error);
                 break;
@@ -187,46 +197,44 @@
 #endif
 
 #if ADB_HOST
-asocket* host_service_to_socket(const char* name, const char* serial, TransportId transport_id) {
-    if (!strcmp(name,"track-devices")) {
+asocket* host_service_to_socket(std::string_view name, std::string_view serial,
+                                TransportId transport_id) {
+    if (name == "track-devices") {
         return create_device_tracker(false);
-    } else if (!strcmp(name, "track-devices-l")) {
+    } else if (name == "track-devices-l") {
         return create_device_tracker(true);
-    } else if (android::base::StartsWith(name, "wait-for-")) {
-        name += strlen("wait-for-");
-
+    } else if (ConsumePrefix(&name, "wait-for-")) {
         std::shared_ptr<state_info> sinfo = std::make_shared<state_info>();
         if (sinfo == nullptr) {
             fprintf(stderr, "couldn't allocate state_info: %s", strerror(errno));
             return nullptr;
         }
 
-        if (serial) sinfo->serial = serial;
+        sinfo->serial = serial;
         sinfo->transport_id = transport_id;
 
-        if (android::base::StartsWith(name, "local")) {
-            name += strlen("local");
+        if (ConsumePrefix(&name, "local")) {
             sinfo->transport_type = kTransportLocal;
-        } else if (android::base::StartsWith(name, "usb")) {
-            name += strlen("usb");
+        } else if (ConsumePrefix(&name, "usb")) {
             sinfo->transport_type = kTransportUsb;
-        } else if (android::base::StartsWith(name, "any")) {
-            name += strlen("any");
+        } else if (ConsumePrefix(&name, "any")) {
             sinfo->transport_type = kTransportAny;
         } else {
             return nullptr;
         }
 
-        if (!strcmp(name, "-device")) {
+        if (name == "-device") {
             sinfo->state = kCsDevice;
-        } else if (!strcmp(name, "-recovery")) {
+        } else if (name == "-recovery") {
             sinfo->state = kCsRecovery;
-        } else if (!strcmp(name, "-sideload")) {
+        } else if (name == "-sideload") {
             sinfo->state = kCsSideload;
-        } else if (!strcmp(name, "-bootloader")) {
+        } else if (name == "-bootloader") {
             sinfo->state = kCsBootloader;
-        } else if (!strcmp(name, "-any")) {
+        } else if (name == "-any") {
             sinfo->state = kCsAny;
+        } else if (name == "-disconnect") {
+            sinfo->state = kCsOffline;
         } else {
             return nullptr;
         }
@@ -235,8 +243,8 @@
             wait_for_state(fd, sinfo.get());
         });
         return create_local_socket(std::move(fd));
-    } else if (!strncmp(name, "connect:", 8)) {
-        std::string host(name + strlen("connect:"));
+    } else if (ConsumePrefix(&name, "connect:")) {
+        std::string host(name);
         unique_fd fd = create_service_thread(
                 "connect", std::bind(connect_service, std::placeholders::_1, host));
         return create_local_socket(std::move(fd));
diff --git a/adb/sockets.cpp b/adb/sockets.cpp
index 420a6d5..8a2bf9a 100644
--- a/adb/sockets.cpp
+++ b/adb/sockets.cpp
@@ -426,22 +426,6 @@
     return s;
 }
 
-#if ADB_HOST
-static asocket* create_host_service_socket(const char* name, const char* serial,
-                                           TransportId transport_id) {
-    asocket* s;
-
-    s = host_service_to_socket(name, serial, transport_id);
-
-    if (s != nullptr) {
-        D("LS(%d) bound to '%s'", s->id, name);
-        return s;
-    }
-
-    return s;
-}
-#endif /* ADB_HOST */
-
 static int remote_socket_enqueue(asocket* s, apacket::payload_type data) {
     D("entered remote_socket_enqueue RS(%d) WRITE fd=%d peer.fd=%d", s->id, s->fd, s->peer->fd);
     apacket* p = get_apacket();
@@ -771,34 +755,27 @@
 
 #if ADB_HOST
     service = std::string_view(s->smart_socket_data).substr(4);
-    if (service.starts_with("host-serial:")) {
-        service.remove_prefix(strlen("host-serial:"));
-
+    if (ConsumePrefix(&service, "host-serial:")) {
         // serial number should follow "host:" and could be a host:port string.
         if (!internal::parse_host_service(&serial, &service, service)) {
             LOG(ERROR) << "SS(" << s->id << "): failed to parse host service: " << service;
             goto fail;
         }
-    } else if (service.starts_with("host-transport-id:")) {
-        service.remove_prefix(strlen("host-transport-id:"));
+    } else if (ConsumePrefix(&service, "host-transport-id:")) {
         if (!ParseUint(&transport_id, service, &service)) {
             LOG(ERROR) << "SS(" << s->id << "): failed to parse host transport id: " << service;
             return -1;
         }
-        if (!service.starts_with(":")) {
+        if (!ConsumePrefix(&service, ":")) {
             LOG(ERROR) << "SS(" << s->id << "): host-transport-id without command";
             return -1;
         }
-        service.remove_prefix(1);
-    } else if (service.starts_with("host-usb:")) {
+    } else if (ConsumePrefix(&service, "host-usb:")) {
         type = kTransportUsb;
-        service.remove_prefix(strlen("host-usb:"));
-    } else if (service.starts_with("host-local:")) {
+    } else if (ConsumePrefix(&service, "host-local:")) {
         type = kTransportLocal;
-        service.remove_prefix(strlen("host-local:"));
-    } else if (service.starts_with("host:")) {
+    } else if (ConsumePrefix(&service, "host:")) {
         type = kTransportAny;
-        service.remove_prefix(strlen("host:"));
     } else {
         service = std::string_view{};
     }
@@ -808,17 +785,22 @@
 
         // Some requests are handled immediately -- in that case the handle_host_request() routine
         // has sent the OKAY or FAIL message and all we have to do is clean up.
-        // TODO: Convert to string_view.
-        if (handle_host_request(std::string(service).c_str(), type,
-                                serial.empty() ? nullptr : std::string(serial).c_str(),
-                                transport_id, s->peer->fd, s)) {
-            LOG(VERBOSE) << "SS(" << s->id << "): handled host service '" << service << "'";
-            goto fail;
-        }
-        if (service.starts_with("transport")) {
-            D("SS(%d): okay transport", s->id);
-            s->smart_socket_data.clear();
-            return 0;
+        auto host_request_result = handle_host_request(
+                service, type, serial.empty() ? nullptr : std::string(serial).c_str(), transport_id,
+                s->peer->fd, s);
+
+        switch (host_request_result) {
+            case HostRequestResult::Handled:
+                LOG(VERBOSE) << "SS(" << s->id << "): handled host service '" << service << "'";
+                goto fail;
+
+            case HostRequestResult::SwitchedTransport:
+                D("SS(%d): okay transport", s->id);
+                s->smart_socket_data.clear();
+                return 0;
+
+            case HostRequestResult::Unhandled:
+                break;
         }
 
         /* try to find a local service with this name.
@@ -826,8 +808,7 @@
         ** and tear down here.
         */
         // TODO: Convert to string_view.
-        s2 = create_host_service_socket(std::string(service).c_str(), std::string(serial).c_str(),
-                                        transport_id);
+        s2 = host_service_to_socket(service, serial, transport_id);
         if (s2 == nullptr) {
             LOG(VERBOSE) << "SS(" << s->id << "): couldn't create host service '" << service << "'";
             SendFail(s->peer->fd, "unknown host service");
diff --git a/adb/transport.cpp b/adb/transport.cpp
index 0c7b0b6..0b4e084 100644
--- a/adb/transport.cpp
+++ b/adb/transport.cpp
@@ -72,6 +72,7 @@
 const char* const kFeatureFixedPushMkdir = "fixed_push_mkdir";
 const char* const kFeatureAbb = "abb";
 const char* const kFeatureFixedPushSymlinkTimestamp = "fixed_push_symlink_timestamp";
+const char* const kFeatureAbbExec = "abb_exec";
 
 namespace {
 
@@ -1013,6 +1014,7 @@
             kFeatureApex,
             kFeatureAbb,
             kFeatureFixedPushSymlinkTimestamp,
+            kFeatureAbbExec,
             // Increment ADB_SERVER_VERSION when adding a feature that adbd needs
             // to know about. Otherwise, the client can be stuck running an old
             // version of the server even after upgrading their copy of adb.
diff --git a/bootstat/OWNERS b/bootstat/OWNERS
index 7fe0443..50b2097 100644
--- a/bootstat/OWNERS
+++ b/bootstat/OWNERS
@@ -1 +1,2 @@
 jhawkins@google.com
+salyzyn@google.com
diff --git a/debuggerd/Android.bp b/debuggerd/Android.bp
index 76c5ade..0cf3378 100644
--- a/debuggerd/Android.bp
+++ b/debuggerd/Android.bp
@@ -218,13 +218,11 @@
         "liblog",
         "libminijail",
         "libnativehelper",
+        "libunwindstack",
     ],
 
     static_libs: [
         "libdebuggerd",
-        "libdexfile_external",  // libunwindstack dependency
-        "libdexfile_support",  // libunwindstack dependency
-        "libunwindstack",
     ],
 
     local_include_dirs: [
diff --git a/fastboot/fastboot_driver.cpp b/fastboot/fastboot_driver.cpp
index 65a5247..fea0a77 100644
--- a/fastboot/fastboot_driver.cpp
+++ b/fastboot/fastboot_driver.cpp
@@ -403,7 +403,7 @@
 RetCode FastBootDriver::HandleResponse(std::string* response, std::vector<std::string>* info,
                                        int* dsize) {
     char status[FB_RESPONSE_SZ + 1];
-    auto start = std::chrono::system_clock::now();
+    auto start = std::chrono::steady_clock::now();
 
     auto set_response = [response](std::string s) {
         if (response) *response = std::move(s);
@@ -414,7 +414,7 @@
 
     // erase response
     set_response("");
-    while ((std::chrono::system_clock::now() - start) < std::chrono::seconds(RESP_TIMEOUT)) {
+    while ((std::chrono::steady_clock::now() - start) < std::chrono::seconds(RESP_TIMEOUT)) {
         int r = transport_->Read(status, FB_RESPONSE_SZ);
         if (r < 0) {
             error_ = ErrnoStr("Status read failed");
@@ -427,6 +427,11 @@
             std::string tmp = input.substr(strlen("INFO"));
             info_(tmp);
             add_info(std::move(tmp));
+            // We may receive one or more INFO packets during long operations,
+            // e.g. flash/erase if they are back by slow media like NAND/NOR
+            // flash. In that case, reset the timer since it's not a real
+            // timeout.
+            start = std::chrono::steady_clock::now();
         } else if (android::base::StartsWith(input, "OKAY")) {
             set_response(input.substr(strlen("OKAY")));
             return SUCCESS;
diff --git a/fs_mgr/Android.bp b/fs_mgr/Android.bp
index 974e13e..4ee9624 100644
--- a/fs_mgr/Android.bp
+++ b/fs_mgr/Android.bp
@@ -111,3 +111,35 @@
         "libgsi_headers",
     ],
 }
+
+cc_binary {
+    name: "remount",
+    defaults: ["fs_mgr_defaults"],
+    static_libs: [
+        "libavb_user",
+    ],
+    shared_libs: [
+        "libbootloader_message",
+        "libbase",
+        "libcrypto",
+        "libfec",
+        "libfs_mgr",
+    ],
+    header_libs: [
+        "libcutils_headers",
+    ],
+    srcs: [
+        "fs_mgr_remount.cpp",
+    ],
+    cppflags: [
+        "-DALLOW_ADBD_DISABLE_VERITY=0",
+    ],
+    product_variables: {
+        debuggable: {
+            cppflags: [
+                "-UALLOW_ADBD_DISABLE_VERITY",
+                "-DALLOW_ADBD_DISABLE_VERITY=1",
+            ],
+        },
+    },
+}
diff --git a/fs_mgr/README.overlayfs.md b/fs_mgr/README.overlayfs.md
index 2aac260..f89e598 100644
--- a/fs_mgr/README.overlayfs.md
+++ b/fs_mgr/README.overlayfs.md
@@ -94,7 +94,7 @@
   and thus free dynamic partition space.
 - Kernel must have CONFIG_OVERLAY_FS=y and will need to be patched
   with "*overlayfs: override_creds=off option bypass creator_cred*"
-  if kernel is higher than 4.6.
+  if kernel is 4.4 or higher.
   The patch is available on the upstream mailing list and the latest as of
   Feb 8 2019 is https://lore.kernel.org/patchwork/patch/1009299/.
   This patch adds an override_creds _mount_ option to overlayfs that
diff --git a/fs_mgr/fs_mgr.cpp b/fs_mgr/fs_mgr.cpp
index 0c904c4..272190e 100644
--- a/fs_mgr/fs_mgr.cpp
+++ b/fs_mgr/fs_mgr.cpp
@@ -1089,7 +1089,7 @@
                 // Skips mounting the device.
                 continue;
             }
-        } else if (!current_entry.avb_key.empty()) {
+        } else if (!current_entry.avb_keys.empty()) {
             if (AvbHandle::SetUpStandaloneAvbHashtree(&current_entry) == AvbHashtreeResult::kFail) {
                 LERROR << "Failed to set up AVB on standalone partition: "
                        << current_entry.mount_point << ", skipping!";
@@ -1320,7 +1320,7 @@
                 // Skips mounting the device.
                 continue;
             }
-        } else if (!fstab_entry.avb_key.empty()) {
+        } else if (!fstab_entry.avb_keys.empty()) {
             if (AvbHandle::SetUpStandaloneAvbHashtree(&fstab_entry) == AvbHashtreeResult::kFail) {
                 LERROR << "Failed to set up AVB on standalone partition: "
                        << fstab_entry.mount_point << ", skipping!";
diff --git a/fs_mgr/fs_mgr_fstab.cpp b/fs_mgr/fs_mgr_fstab.cpp
index 82d9144..2f1e41f 100644
--- a/fs_mgr/fs_mgr_fstab.cpp
+++ b/fs_mgr/fs_mgr_fstab.cpp
@@ -307,6 +307,8 @@
             } else {
                 entry->logical_blk_size = val;
             }
+        } else if (StartsWith(flag, "avb_keys=")) {  // must before the following "avb"
+            entry->avb_keys = arg;
         } else if (StartsWith(flag, "avb")) {
             entry->fs_mgr_flags.avb = true;
             entry->vbmeta_partition = arg;
@@ -325,8 +327,6 @@
             }
         } else if (StartsWith(flag, "zram_backing_dev_path=")) {
             entry->zram_backing_dev_path = arg;
-        } else if (StartsWith(flag, "avb_key=")) {
-            entry->avb_key = arg;
         } else {
             LWARNING << "Warning: unknown flag: " << flag;
         }
@@ -759,7 +759,8 @@
                          .fs_type = "ext4",
                          .flags = MS_RDONLY,
                          .fs_options = "barrier=1",
-                         .avb_key = "/gsi.avbpubkey",
+                         // could add more keys separated by ':'.
+                         .avb_keys = "/avb/gsi.avbpubkey:",
                          .logical_partition_name = "system"};
     system.fs_mgr_flags.wait = true;
     system.fs_mgr_flags.logical = true;
diff --git a/fs_mgr/fs_mgr_overlayfs.cpp b/fs_mgr/fs_mgr_overlayfs.cpp
index 9364b2d..40da36d 100644
--- a/fs_mgr/fs_mgr_overlayfs.cpp
+++ b/fs_mgr/fs_mgr_overlayfs.cpp
@@ -157,7 +157,12 @@
         fs_mgr_update_logical_partition(entry);
     }
     auto save_errno = errno;
+    errno = 0;
     auto has_shared_blocks = fs_mgr_has_shared_blocks(entry->mount_point, entry->blk_device);
+    // special case for first stage init for system as root (taimen)
+    if (!has_shared_blocks && (errno == ENOENT) && (entry->blk_device == "/dev/root")) {
+        has_shared_blocks = true;
+    }
     errno = save_errno;
     return has_shared_blocks;
 }
@@ -1026,7 +1031,7 @@
     if (major > 4) {
         return OverlayfsValidResult::kNotSupported;
     }
-    if (minor > 6) {
+    if (minor > 3) {
         return OverlayfsValidResult::kNotSupported;
     }
     return OverlayfsValidResult::kOk;
diff --git a/fs_mgr/fs_mgr_remount.cpp b/fs_mgr/fs_mgr_remount.cpp
new file mode 100644
index 0000000..6312734
--- /dev/null
+++ b/fs_mgr/fs_mgr_remount.cpp
@@ -0,0 +1,388 @@
+/*
+ * Copyright (C) 2019 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <errno.h>
+#include <getopt.h>
+#include <libavb_user/libavb_user.h>
+#include <stdio.h>
+#include <sys/mount.h>
+#include <sys/types.h>
+#include <sys/vfs.h>
+#include <unistd.h>
+
+#include <string>
+#include <utility>
+#include <vector>
+
+#include <android-base/file.h>
+#include <android-base/logging.h>
+#include <android-base/properties.h>
+#include <android-base/strings.h>
+#include <bootloader_message/bootloader_message.h>
+#include <cutils/android_reboot.h>
+#include <fec/io.h>
+#include <fs_mgr_overlayfs.h>
+#include <fs_mgr_priv.h>
+#include <fstab/fstab.h>
+
+namespace {
+
+[[noreturn]] void usage(int exit_status) {
+    LOG(INFO) << getprogname()
+              << " [-h] [-R] [-T fstab_file] [partition]...\n"
+                 "\t-h --help\tthis help\n"
+                 "\t-R --reboot\tdisable verity & reboot to facilitate remount\n"
+                 "\t-T --fstab\tcustom fstab file location\n"
+                 "\tpartition\tspecific partition(s) (empty does all)\n"
+                 "\n"
+                 "Remount specified partition(s) read-write, by name or mount point.\n"
+                 "-R notwithstanding, verity must be disabled on partition(s).";
+
+    ::exit(exit_status);
+}
+
+bool remountable_partition(const android::fs_mgr::FstabEntry& entry) {
+    if (entry.fs_mgr_flags.vold_managed) return false;
+    if (entry.fs_mgr_flags.recovery_only) return false;
+    if (entry.fs_mgr_flags.slot_select_other) return false;
+    if (!(entry.flags & MS_RDONLY)) return false;
+    if (entry.fs_type == "vfat") return false;
+    return true;
+}
+
+const std::string system_mount_point(const android::fs_mgr::FstabEntry& entry) {
+    if (entry.mount_point == "/") return "/system";
+    return entry.mount_point;
+}
+
+const android::fs_mgr::FstabEntry* is_wrapped(const android::fs_mgr::Fstab& overlayfs_candidates,
+                                              const android::fs_mgr::FstabEntry& entry) {
+    auto mount_point = system_mount_point(entry);
+    auto it = std::find_if(overlayfs_candidates.begin(), overlayfs_candidates.end(),
+                           [&mount_point](const auto& entry) {
+                               return android::base::StartsWith(mount_point,
+                                                                system_mount_point(entry) + "/");
+                           });
+    if (it == overlayfs_candidates.end()) return nullptr;
+    return &(*it);
+}
+
+void try_unmount_bionic(android::fs_mgr::Fstab* mounts) {
+    static constexpr const char* kBionic = "/bionic";
+
+    auto entry = GetEntryForMountPoint(mounts, kBionic);
+    if (!entry) return;
+
+    struct statfs buf;
+    if (::statfs(kBionic, &buf) == -1) {
+        PLOG(ERROR) << "statfs of " << kBionic;
+        return;
+    }
+    if (buf.f_flags & MS_RDONLY) {
+        // /bionic is on a read-only partition; can happen for
+        // non-system-as-root-devices. Don' try to unmount.
+        return;
+    }
+    fs_mgr_set_blk_ro(entry->blk_device, false);
+    if (::mount(entry->blk_device.c_str(), entry->mount_point.c_str(), entry->fs_type.c_str(),
+                MS_REMOUNT, nullptr) == -1) {
+        PLOG(ERROR) << "remount of " << kBionic;
+    }
+}
+
+void MyLogger(android::base::LogId id, android::base::LogSeverity severity, const char* tag,
+              const char* file, unsigned int line, const char* message) {
+    static const char log_characters[] = "VD\0WEFF";
+    if (severity < sizeof(log_characters)) {
+        auto severity_char = log_characters[severity];
+        if (severity_char) fprintf(stderr, "%c ", severity_char);
+    }
+    fprintf(stderr, "%s\n", message);
+
+    static auto logd = android::base::LogdLogger();
+    logd(id, severity, tag, file, line, message);
+}
+
+[[noreturn]] void reboot(bool dedupe) {
+    if (dedupe) {
+        LOG(INFO) << "The device will now reboot to recovery and attempt un-deduplication.";
+    } else {
+        LOG(INFO) << "Successfully disabled verity\nrebooting device";
+    }
+    ::sync();
+    android::base::SetProperty(ANDROID_RB_PROPERTY, dedupe ? "reboot,recovery" : "reboot,remount");
+    ::sleep(60);
+    ::exit(0);  // SUCCESS
+}
+
+}  // namespace
+
+int main(int argc, char* argv[]) {
+    android::base::InitLogging(argv, MyLogger);
+
+    enum {
+        SUCCESS,
+        NOT_USERDEBUG,
+        BADARG,
+        NOT_ROOT,
+        NO_FSTAB,
+        UNKNOWN_PARTITION,
+        INVALID_PARTITION,
+        VERITY_PARTITION,
+        BAD_OVERLAY,
+        NO_MOUNTS,
+        REMOUNT_FAILED,
+    } retval = SUCCESS;
+
+    // If somehow this executable is delivered on a "user" build, it can
+    // not function, so providing a clear message to the caller rather than
+    // letting if fall through and provide a lot of confusing failure messages.
+    if (!ALLOW_ADBD_DISABLE_VERITY || (android::base::GetProperty("ro.debuggable", "0") != "1")) {
+        LOG(ERROR) << "only functions on userdebug or eng builds";
+        return NOT_USERDEBUG;
+    }
+
+    const char* fstab_file = nullptr;
+    auto can_reboot = false;
+
+    struct option longopts[] = {
+            {"fstab", required_argument, nullptr, 'T'},
+            {"help", no_argument, nullptr, 'h'},
+            {"reboot", no_argument, nullptr, 'R'},
+            {0, 0, nullptr, 0},
+    };
+    for (int opt; (opt = ::getopt_long(argc, argv, "hRT:", longopts, nullptr)) != -1;) {
+        switch (opt) {
+            case 'R':
+                can_reboot = true;
+                break;
+            case 'T':
+                if (fstab_file) {
+                    LOG(ERROR) << "Cannot supply two fstabs: -T " << fstab_file << " -T" << optarg;
+                    usage(BADARG);
+                }
+                fstab_file = optarg;
+                break;
+            default:
+                LOG(ERROR) << "Bad Argument -" << char(opt);
+                usage(BADARG);
+                break;
+            case 'h':
+                usage(SUCCESS);
+                break;
+        }
+    }
+
+    // Make sure we are root.
+    if (::getuid() != 0) {
+        LOG(ERROR) << "must be run as root";
+        return NOT_ROOT;
+    }
+
+    // Read the selected fstab.
+    android::fs_mgr::Fstab fstab;
+    auto fstab_read = false;
+    if (fstab_file) {
+        fstab_read = android::fs_mgr::ReadFstabFromFile(fstab_file, &fstab);
+    } else {
+        fstab_read = android::fs_mgr::ReadDefaultFstab(&fstab);
+    }
+    if (!fstab_read || fstab.empty()) {
+        PLOG(ERROR) << "Failed to read fstab";
+        return NO_FSTAB;
+    }
+
+    // Generate the list of supported overlayfs mount points.
+    auto overlayfs_candidates = fs_mgr_overlayfs_candidate_list(fstab);
+
+    // Generate the all remountable partitions sub-list
+    android::fs_mgr::Fstab all;
+    for (auto const& entry : fstab) {
+        if (!remountable_partition(entry)) continue;
+        if (overlayfs_candidates.empty() ||
+            GetEntryForMountPoint(&overlayfs_candidates, entry.mount_point) ||
+            (is_wrapped(overlayfs_candidates, entry) == nullptr)) {
+            all.emplace_back(entry);
+        }
+    }
+
+    // Parse the unique list of valid partition arguments.
+    android::fs_mgr::Fstab partitions;
+    for (; argc > optind; ++optind) {
+        auto partition = std::string(argv[optind]);
+        if (partition.empty()) continue;
+        if (partition == "/") partition = "/system";
+        auto find_part = [&partition](const auto& entry) {
+            const auto mount_point = system_mount_point(entry);
+            if (partition == mount_point) return true;
+            if (partition == android::base::Basename(mount_point)) return true;
+            return false;
+        };
+        // Do we know about the partition?
+        auto it = std::find_if(fstab.begin(), fstab.end(), find_part);
+        if (it == fstab.end()) {
+            LOG(ERROR) << "Unknown partition " << partition << ", skipping";
+            retval = UNKNOWN_PARTITION;
+            continue;
+        }
+        // Is that one covered by an existing overlayfs?
+        auto wrap = is_wrapped(overlayfs_candidates, *it);
+        if (wrap) {
+            LOG(INFO) << "partition " << partition << " covered by overlayfs for "
+                      << wrap->mount_point << ", switching";
+            partition = system_mount_point(*wrap);
+        }
+        // Is it a remountable partition?
+        it = std::find_if(all.begin(), all.end(), find_part);
+        if (it == all.end()) {
+            LOG(ERROR) << "Invalid partition " << partition << ", skipping";
+            retval = INVALID_PARTITION;
+            continue;
+        }
+        if (GetEntryForMountPoint(&partitions, it->mount_point) == nullptr) {
+            partitions.emplace_back(*it);
+        }
+    }
+
+    if (partitions.empty() && !retval) {
+        partitions = all;
+    }
+
+    // Check verity and optionally setup overlayfs backing.
+    auto reboot_later = false;
+    for (auto it = partitions.begin(); it != partitions.end();) {
+        auto& entry = *it;
+        auto& mount_point = entry.mount_point;
+        if (fs_mgr_is_verity_enabled(entry)) {
+            LOG(WARNING) << "Verity enabled on " << mount_point;
+            if (can_reboot &&
+                (android::base::GetProperty("ro.boot.vbmeta.devices_state", "") != "locked")) {
+                if (AvbOps* ops = avb_ops_user_new()) {
+                    auto ret = avb_user_verity_set(
+                            ops, android::base::GetProperty("ro.boot.slot_suffix", "").c_str(),
+                            false);
+                    avb_ops_user_free(ops);
+                    if (ret) {
+                        if (fs_mgr_overlayfs_valid() == OverlayfsValidResult::kNotSupported) {
+                            retval = VERITY_PARTITION;
+                            // w/o overlayfs available, also check for dedupe
+                            reboot_later = true;
+                            ++it;
+                            continue;
+                        }
+                        reboot(false);
+                    } else if (fs_mgr_set_blk_ro(entry.blk_device, false)) {
+                        fec::io fh(entry.blk_device.c_str(), O_RDWR);
+                        if (fh && fh.set_verity_status(false)) reboot_later = true;
+                    }
+                }
+            }
+            LOG(ERROR) << "Skipping " << mount_point;
+            retval = VERITY_PARTITION;
+            it = partitions.erase(it);
+            continue;
+        }
+
+        auto change = false;
+        errno = 0;
+        if (fs_mgr_overlayfs_setup(nullptr, mount_point.c_str(), &change)) {
+            if (change) {
+                LOG(INFO) << "Using overlayfs for " << mount_point;
+            }
+        } else if (errno) {
+            PLOG(ERROR) << "Overlayfs setup for " << mount_point << " failed, skipping";
+            retval = BAD_OVERLAY;
+            it = partitions.erase(it);
+            continue;
+        }
+        ++it;
+    }
+
+    if (partitions.empty()) {
+        if (reboot_later) reboot(false);
+        LOG(WARNING) << "No partitions to remount";
+        return retval;
+    }
+
+    // Mount overlayfs.
+    if (!fs_mgr_overlayfs_mount_all(&partitions)) {
+        retval = BAD_OVERLAY;
+        PLOG(ERROR) << "Can not mount overlayfs for partitions";
+    }
+
+    // Get actual mounts _after_ overlayfs has been added.
+    android::fs_mgr::Fstab mounts;
+    if (!android::fs_mgr::ReadFstabFromFile("/proc/mounts", &mounts) || mounts.empty()) {
+        PLOG(ERROR) << "Failed to read /proc/mounts";
+        retval = NO_MOUNTS;
+    }
+
+    // Remount selected partitions.
+    for (auto& entry : partitions) {
+        // unlock the r/o key for the mount point device
+        if (entry.fs_mgr_flags.logical) {
+            fs_mgr_update_logical_partition(&entry);
+        }
+        auto blk_device = entry.blk_device;
+        auto mount_point = entry.mount_point;
+
+        for (auto it = mounts.rbegin(); it != mounts.rend(); ++it) {
+            auto& rentry = *it;
+            if (mount_point == rentry.mount_point) {
+                blk_device = rentry.blk_device;
+                break;
+            }
+            if ((mount_point == "/") && (rentry.mount_point == "/system")) {
+                if (blk_device != "/dev/root") blk_device = rentry.blk_device;
+                mount_point = "/system";
+                break;
+            }
+        }
+        fs_mgr_set_blk_ro(blk_device, false);
+
+        // Now remount!
+        if (::mount(blk_device.c_str(), mount_point.c_str(), entry.fs_type.c_str(), MS_REMOUNT,
+                    nullptr) == 0) {
+            continue;
+        }
+        if ((errno == EINVAL) && (mount_point != entry.mount_point)) {
+            mount_point = entry.mount_point;
+            if (::mount(blk_device.c_str(), mount_point.c_str(), entry.fs_type.c_str(), MS_REMOUNT,
+                        nullptr) == 0) {
+                continue;
+            }
+        }
+        PLOG(WARNING) << "failed to remount partition dev:" << blk_device << " mnt:" << mount_point;
+        // If errno = EROFS at this point, we are dealing with r/o
+        // filesystem types like squashfs, erofs or ext4 dedupe. We will
+        // consider such a device that does not have CONFIG_OVERLAY_FS
+        // in the kernel as a misconfigured; except for ext4 dedupe.
+        if ((errno == EROFS) && can_reboot) {
+            const std::vector<std::string> msg = {"--fsck_unshare_blocks"};
+            std::string err;
+            if (write_bootloader_message(msg, &err)) reboot(true);
+            LOG(ERROR) << "Failed to set bootloader message: " << err;
+            errno = EROFS;
+        }
+        retval = REMOUNT_FAILED;
+    }
+
+    if (reboot_later) reboot(false);
+
+    try_unmount_bionic(&mounts);
+
+    return retval;
+}
diff --git a/fs_mgr/include_fstab/fstab/fstab.h b/fs_mgr/include_fstab/fstab/fstab.h
index a3d9fdd..e811447 100644
--- a/fs_mgr/include_fstab/fstab/fstab.h
+++ b/fs_mgr/include_fstab/fstab/fstab.h
@@ -55,7 +55,7 @@
     std::string zram_loopback_path;
     uint64_t zram_loopback_size = 512 * 1024 * 1024;  // 512MB by default;
     std::string zram_backing_dev_path;
-    std::string avb_key;
+    std::string avb_keys;
 
     struct FsMgrFlags {
         bool wait : 1;
diff --git a/fs_mgr/libfiemap_writer/Android.bp b/fs_mgr/libfiemap_writer/Android.bp
index 33c3cad..7463810 100644
--- a/fs_mgr/libfiemap_writer/Android.bp
+++ b/fs_mgr/libfiemap_writer/Android.bp
@@ -20,13 +20,17 @@
     recovery_available: true,
     export_include_dirs: ["include"],
     cflags: [
-        // TODO(b/121211685): Allows us to create a skeleton of required classes
-        "-Wno-unused-private-field",
-        "-Wno-unused-parameter",
+        "-D_FILE_OFFSET_BITS=64",
     ],
 
     srcs: [
         "fiemap_writer.cpp",
+        "split_fiemap_writer.cpp",
+        "utility.cpp",
+    ],
+
+    static_libs: [
+        "libext4_utils",
     ],
 
     header_libs: [
diff --git a/fs_mgr/libfiemap_writer/fiemap_writer.cpp b/fs_mgr/libfiemap_writer/fiemap_writer.cpp
index b9b75f8..3d41876 100644
--- a/fs_mgr/libfiemap_writer/fiemap_writer.cpp
+++ b/fs_mgr/libfiemap_writer/fiemap_writer.cpp
@@ -27,6 +27,7 @@
 #include <sys/vfs.h>
 #include <unistd.h>
 
+#include <limits>
 #include <string>
 #include <utility>
 #include <vector>
@@ -126,7 +127,8 @@
     return DeviceMapperStackPop(bdev_next, bdev_raw);
 }
 
-static bool FileToBlockDevicePath(const std::string& file_path, std::string* bdev_path) {
+bool FiemapWriter::GetBlockDeviceForFile(const std::string& file_path, std::string* bdev_path,
+                                         bool* uses_dm) {
     struct stat sb;
     if (stat(file_path.c_str(), &sb)) {
         PLOG(ERROR) << "Failed to get stat for: " << file_path;
@@ -146,6 +148,10 @@
         return false;
     }
 
+    if (uses_dm) {
+        *uses_dm = (bdev_raw != bdev);
+    }
+
     LOG(DEBUG) << "Popped device (" << bdev_raw << ") from device mapper stack starting with ("
                << bdev << ")";
 
@@ -195,17 +201,21 @@
         return false;
     }
 
-    if (file_size % sfs.f_bsize) {
-        LOG(ERROR) << "File size " << file_size << " is not aligned to optimal block size "
-                   << sfs.f_bsize << " for file " << file_path;
+    if (!sfs.f_bsize) {
+        LOG(ERROR) << "Unsupported block size: " << sfs.f_bsize;
         return false;
     }
 
     // Check if the filesystem is of supported types.
-    // Only ext4 and f2fs are tested and supported.
-    if ((sfs.f_type != EXT4_SUPER_MAGIC) && (sfs.f_type != F2FS_SUPER_MAGIC)) {
-        LOG(ERROR) << "Unsupported file system type: 0x" << std::hex << sfs.f_type;
-        return false;
+    // Only ext4, f2fs, and vfat are tested and supported.
+    switch (sfs.f_type) {
+        case EXT4_SUPER_MAGIC:
+        case F2FS_SUPER_MAGIC:
+        case MSDOS_SUPER_MAGIC:
+            break;
+        default:
+            LOG(ERROR) << "Unsupported file system type: 0x" << std::hex << sfs.f_type;
+            return false;
     }
 
     uint64_t available_bytes = sfs.f_bsize * sfs.f_bavail;
@@ -220,14 +230,46 @@
 }
 
 static bool AllocateFile(int file_fd, const std::string& file_path, uint64_t blocksz,
-                         uint64_t file_size, std::function<bool(uint64_t, uint64_t)> on_progress) {
+                         uint64_t file_size, unsigned int fs_type,
+                         std::function<bool(uint64_t, uint64_t)> on_progress) {
     // Reserve space for the file on the file system and write it out to make sure the extents
     // don't come back unwritten. Return from this function with the kernel file offset set to 0.
     // If the filesystem is f2fs, then we also PIN the file on disk to make sure the blocks
     // aren't moved around.
-    if (fallocate(file_fd, FALLOC_FL_ZERO_RANGE, 0, file_size)) {
-        PLOG(ERROR) << "Failed to allocate space for file: " << file_path << " size: " << file_size;
-        return false;
+    switch (fs_type) {
+        case EXT4_SUPER_MAGIC:
+        case F2FS_SUPER_MAGIC:
+            if (fallocate(file_fd, FALLOC_FL_ZERO_RANGE, 0, file_size)) {
+                PLOG(ERROR) << "Failed to allocate space for file: " << file_path
+                            << " size: " << file_size;
+                return false;
+            }
+            break;
+        case MSDOS_SUPER_MAGIC: {
+            // fallocate() is not supported, and not needed, since VFAT does not support holes.
+            // Instead we can perform a much faster allocation.
+            auto offset = TEMP_FAILURE_RETRY(lseek(file_fd, file_size - 1, SEEK_SET));
+            if (offset < 0) {
+                PLOG(ERROR) << "Failed to lseek " << file_path;
+                return false;
+            }
+            if (offset != file_size - 1) {
+                LOG(ERROR) << "Seek returned wrong offset " << offset << " for file " << file_path;
+                return false;
+            }
+            char buffer[] = {0};
+            if (!android::base::WriteFully(file_fd, buffer, 1)) {
+                PLOG(ERROR) << "Write failed: " << file_path;
+                return false;
+            }
+            if (on_progress && !on_progress(file_size, file_size)) {
+                return false;
+            }
+            return true;
+        }
+        default:
+            LOG(ERROR) << "Missing fallocate() support for file system " << fs_type;
+            return false;
     }
 
     // write zeroes in 'blocksz' byte increments until we reach file_size to make sure the data
@@ -282,9 +324,9 @@
 }
 
 static bool PinFile(int file_fd, const std::string& file_path, uint32_t fs_type) {
-    if (fs_type == EXT4_SUPER_MAGIC) {
-        // No pinning necessary for ext4. The blocks, once allocated, are expected
-        // to be fixed.
+    if (fs_type != F2FS_SUPER_MAGIC) {
+        // No pinning necessary for ext4/msdos. The blocks, once allocated, are
+        // expected to be fixed.
         return true;
     }
 
@@ -319,9 +361,9 @@
 }
 
 static bool IsFilePinned(int file_fd, const std::string& file_path, uint32_t fs_type) {
-    if (fs_type == EXT4_SUPER_MAGIC) {
-        // No pinning necessary for ext4. The blocks, once allocated, are expected
-        // to be fixed.
+    if (fs_type != F2FS_SUPER_MAGIC) {
+        // No pinning necessary for ext4 or vfat. The blocks, once allocated,
+        // are expected to be fixed.
         return true;
     }
 
@@ -433,6 +475,44 @@
     return last_extent_seen;
 }
 
+static bool ReadFibmap(int file_fd, const std::string& file_path,
+                       std::vector<struct fiemap_extent>* extents) {
+    struct stat s;
+    if (fstat(file_fd, &s)) {
+        PLOG(ERROR) << "Failed to stat " << file_path;
+        return false;
+    }
+
+    uint64_t num_blocks = (s.st_size + s.st_blksize - 1) / s.st_blksize;
+    if (num_blocks > std::numeric_limits<uint32_t>::max()) {
+        LOG(ERROR) << "Too many blocks for FIBMAP (" << num_blocks << ")";
+        return false;
+    }
+
+    for (uint32_t last_block, block_number = 0; block_number < num_blocks; block_number++) {
+        uint32_t block = block_number;
+        if (ioctl(file_fd, FIBMAP, &block)) {
+            PLOG(ERROR) << "Failed to get FIBMAP for file " << file_path;
+            return false;
+        }
+        if (!block) {
+            LOG(ERROR) << "Logical block " << block_number << " is a hole, which is not supported";
+            return false;
+        }
+
+        if (!extents->empty() && block == last_block + 1) {
+            extents->back().fe_length++;
+        } else {
+            extents->push_back(fiemap_extent{.fe_logical = block_number,
+                                             .fe_physical = block,
+                                             .fe_length = 1,
+                                             .fe_flags = 0});
+        }
+        last_block = block;
+    }
+    return true;
+}
+
 FiemapUniquePtr FiemapWriter::Open(const std::string& file_path, uint64_t file_size, bool create,
                                    std::function<bool(uint64_t, uint64_t)> progress) {
     // if 'create' is false, open an existing file and do not truncate.
@@ -458,7 +538,7 @@
     }
 
     std::string bdev_path;
-    if (!FileToBlockDevicePath(abs_path, &bdev_path)) {
+    if (!GetBlockDeviceForFile(abs_path, &bdev_path)) {
         LOG(ERROR) << "Failed to get block dev path for file: " << file_path;
         cleanup(abs_path, create);
         return nullptr;
@@ -495,8 +575,13 @@
         return nullptr;
     }
 
+    // Align up to the nearest block size.
+    if (file_size % blocksz) {
+        file_size += blocksz - (file_size % blocksz);
+    }
+
     if (create) {
-        if (!AllocateFile(file_fd, abs_path, blocksz, file_size, std::move(progress))) {
+        if (!AllocateFile(file_fd, abs_path, blocksz, file_size, fs_type, std::move(progress))) {
             LOG(ERROR) << "Failed to allocate file: " << abs_path << " of size: " << file_size
                        << " bytes";
             cleanup(abs_path, create);
@@ -513,10 +598,22 @@
 
     // now allocate the FiemapWriter and start setting it up
     FiemapUniquePtr fmap(new FiemapWriter());
-    if (!ReadFiemap(file_fd, abs_path, &fmap->extents_)) {
-        LOG(ERROR) << "Failed to read fiemap of file: " << abs_path;
-        cleanup(abs_path, create);
-        return nullptr;
+    switch (fs_type) {
+        case EXT4_SUPER_MAGIC:
+        case F2FS_SUPER_MAGIC:
+            if (!ReadFiemap(file_fd, abs_path, &fmap->extents_)) {
+                LOG(ERROR) << "Failed to read fiemap of file: " << abs_path;
+                cleanup(abs_path, create);
+                return nullptr;
+            }
+            break;
+        case MSDOS_SUPER_MAGIC:
+            if (!ReadFibmap(file_fd, abs_path, &fmap->extents_)) {
+                LOG(ERROR) << "Failed to read fibmap of file: " << abs_path;
+                cleanup(abs_path, create);
+                return nullptr;
+            }
+            break;
     }
 
     fmap->file_path_ = abs_path;
@@ -527,14 +624,10 @@
     fmap->fs_type_ = fs_type;
     fmap->block_size_ = blocksz;
 
-    LOG(INFO) << "Successfully created FiemapWriter for file " << abs_path << " on block device "
-              << bdev_path;
+    LOG(VERBOSE) << "Successfully created FiemapWriter for file " << abs_path << " on block device "
+                 << bdev_path;
     return fmap;
 }
 
-bool FiemapWriter::Read(off64_t off, uint8_t* buffer, uint64_t size) {
-    return false;
-}
-
 }  // namespace fiemap_writer
 }  // namespace android
diff --git a/fs_mgr/libfiemap_writer/fiemap_writer_test.cpp b/fs_mgr/libfiemap_writer/fiemap_writer_test.cpp
index 41fa959..ab4efae 100644
--- a/fs_mgr/libfiemap_writer/fiemap_writer_test.cpp
+++ b/fs_mgr/libfiemap_writer/fiemap_writer_test.cpp
@@ -22,6 +22,7 @@
 #include <sys/mount.h>
 #include <sys/stat.h>
 #include <sys/types.h>
+#include <sys/vfs.h>
 #include <unistd.h>
 
 #include <string>
@@ -32,23 +33,26 @@
 #include <android-base/unique_fd.h>
 #include <gtest/gtest.h>
 #include <libdm/loop_control.h>
-
 #include <libfiemap_writer/fiemap_writer.h>
+#include <libfiemap_writer/split_fiemap_writer.h>
+
+#include "utility.h"
 
 using namespace std;
+using namespace std::string_literals;
 using namespace android::fiemap_writer;
 using unique_fd = android::base::unique_fd;
 using LoopDevice = android::dm::LoopDevice;
 
-std::string testbdev = "";
+std::string gTestDir;
 uint64_t testfile_size = 536870912;  // default of 512MiB
+size_t gBlockSize = 0;
 
 class FiemapWriterTest : public ::testing::Test {
   protected:
     void SetUp() override {
         const ::testing::TestInfo* tinfo = ::testing::UnitTest::GetInstance()->current_test_info();
-        std::string exec_dir = ::android::base::GetExecutableDirectory();
-        testfile = ::android::base::StringPrintf("%s/testdata/%s", exec_dir.c_str(), tinfo->name());
+        testfile = gTestDir + "/"s + tinfo->name();
     }
 
     void TearDown() override { unlink(testfile.c_str()); }
@@ -57,6 +61,24 @@
     std::string testfile;
 };
 
+class SplitFiemapTest : public ::testing::Test {
+  protected:
+    void SetUp() override {
+        const ::testing::TestInfo* tinfo = ::testing::UnitTest::GetInstance()->current_test_info();
+        testfile = gTestDir + "/"s + tinfo->name();
+    }
+
+    void TearDown() override {
+        std::string message;
+        if (!SplitFiemap::RemoveSplitFiles(testfile, &message)) {
+            cerr << "Could not remove all split files: " << message;
+        }
+    }
+
+    // name of the file we use for testing
+    std::string testfile;
+};
+
 TEST_F(FiemapWriterTest, CreateImpossiblyLargeFile) {
     // Try creating a file of size ~100TB but aligned to
     // 512 byte to make sure block alignment tests don't
@@ -69,39 +91,47 @@
 
 TEST_F(FiemapWriterTest, CreateUnalignedFile) {
     // Try creating a file of size 4097 bytes which is guaranteed
-    // to be unaligned to all known block sizes. The creation must
-    // fail.
-    FiemapUniquePtr fptr = FiemapWriter::Open(testfile, 4097);
-    EXPECT_EQ(fptr, nullptr);
-    EXPECT_EQ(access(testfile.c_str(), F_OK), -1);
-    EXPECT_EQ(errno, ENOENT);
+    // to be unaligned to all known block sizes.
+    FiemapUniquePtr fptr = FiemapWriter::Open(testfile, gBlockSize + 1);
+    ASSERT_NE(fptr, nullptr);
+    ASSERT_EQ(fptr->size(), gBlockSize * 2);
 }
 
 TEST_F(FiemapWriterTest, CheckFilePath) {
-    FiemapUniquePtr fptr = FiemapWriter::Open(testfile, 4096);
+    FiemapUniquePtr fptr = FiemapWriter::Open(testfile, gBlockSize);
     ASSERT_NE(fptr, nullptr);
-    EXPECT_EQ(fptr->size(), 4096);
+    EXPECT_EQ(fptr->size(), gBlockSize);
     EXPECT_EQ(fptr->file_path(), testfile);
     EXPECT_EQ(access(testfile.c_str(), F_OK), 0);
 }
 
 TEST_F(FiemapWriterTest, CheckProgress) {
-    std::vector<uint64_t> expected{
-            0,
-            4096,
-    };
+    std::vector<uint64_t> expected;
     size_t invocations = 0;
     auto callback = [&](uint64_t done, uint64_t total) -> bool {
         EXPECT_LT(invocations, expected.size());
         EXPECT_EQ(done, expected[invocations]);
-        EXPECT_EQ(total, 4096);
+        EXPECT_EQ(total, gBlockSize);
         invocations++;
         return true;
     };
 
-    auto ptr = FiemapWriter::Open(testfile, 4096, true, std::move(callback));
+    uint32_t fs_type;
+    {
+        auto ptr = FiemapWriter::Open(testfile, gBlockSize, true);
+        ASSERT_NE(ptr, nullptr);
+        fs_type = ptr->fs_type();
+    }
+    ASSERT_EQ(unlink(testfile.c_str()), 0);
+
+    if (fs_type != MSDOS_SUPER_MAGIC) {
+        expected.push_back(0);
+    }
+    expected.push_back(gBlockSize);
+
+    auto ptr = FiemapWriter::Open(testfile, gBlockSize, true, std::move(callback));
     EXPECT_NE(ptr, nullptr);
-    EXPECT_EQ(invocations, 2);
+    EXPECT_EQ(invocations, expected.size());
 }
 
 TEST_F(FiemapWriterTest, CheckPinning) {
@@ -111,9 +141,10 @@
 }
 
 TEST_F(FiemapWriterTest, CheckBlockDevicePath) {
-    FiemapUniquePtr fptr = FiemapWriter::Open(testfile, 4096);
-    EXPECT_EQ(fptr->size(), 4096);
-    EXPECT_EQ(fptr->bdev_path(), testbdev);
+    FiemapUniquePtr fptr = FiemapWriter::Open(testfile, gBlockSize);
+    EXPECT_EQ(fptr->size(), gBlockSize);
+    EXPECT_EQ(fptr->bdev_path().find("/dev/block/"), size_t(0));
+    EXPECT_EQ(fptr->bdev_path().find("/dev/block/dm-"), string::npos);
 }
 
 TEST_F(FiemapWriterTest, CheckFileCreated) {
@@ -138,45 +169,69 @@
     EXPECT_GT(fptr->extents().size(), 0);
 }
 
-class TestExistingFile : public ::testing::Test {
-  protected:
-    void SetUp() override {
-        std::string exec_dir = ::android::base::GetExecutableDirectory();
-        unaligned_file_ = exec_dir + "/testdata/unaligned_file";
-        file_4k_ = exec_dir + "/testdata/file_4k";
-        file_32k_ = exec_dir + "/testdata/file_32k";
+TEST_F(FiemapWriterTest, ExistingFile) {
+    // Create the file.
+    { ASSERT_NE(FiemapWriter::Open(testfile, gBlockSize), nullptr); }
+    // Test that we can still open it.
+    {
+        auto ptr = FiemapWriter::Open(testfile, 0, false);
+        ASSERT_NE(ptr, nullptr);
+        EXPECT_GT(ptr->extents().size(), 0);
+    }
+}
 
-        CleanupFiles();
-        fptr_unaligned = FiemapWriter::Open(unaligned_file_, 4097);
-        fptr_4k = FiemapWriter::Open(file_4k_, 4096);
-        fptr_32k = FiemapWriter::Open(file_32k_, 32768);
+TEST_F(FiemapWriterTest, FileDeletedOnError) {
+    auto callback = [](uint64_t, uint64_t) -> bool { return false; };
+    auto ptr = FiemapWriter::Open(testfile, gBlockSize, true, std::move(callback));
+    EXPECT_EQ(ptr, nullptr);
+    EXPECT_EQ(access(testfile.c_str(), F_OK), -1);
+    EXPECT_EQ(errno, ENOENT);
+}
+
+TEST_F(FiemapWriterTest, MaxBlockSize) {
+    ASSERT_GT(DetermineMaximumFileSize(testfile), 0);
+}
+
+TEST_F(SplitFiemapTest, Create) {
+    auto ptr = SplitFiemap::Create(testfile, 1024 * 768, 1024 * 32);
+    ASSERT_NE(ptr, nullptr);
+
+    auto extents = ptr->extents();
+
+    // Destroy the fiemap, closing file handles. This should not delete them.
+    ptr = nullptr;
+
+    std::vector<std::string> files;
+    ASSERT_TRUE(SplitFiemap::GetSplitFileList(testfile, &files));
+    for (const auto& path : files) {
+        EXPECT_EQ(access(path.c_str(), F_OK), 0);
     }
 
-    void TearDown() { CleanupFiles(); }
+    ASSERT_GE(extents.size(), files.size());
+}
 
-    void CleanupFiles() {
-        unlink(unaligned_file_.c_str());
-        unlink(file_4k_.c_str());
-        unlink(file_32k_.c_str());
+TEST_F(SplitFiemapTest, Open) {
+    {
+        auto ptr = SplitFiemap::Create(testfile, 1024 * 768, 1024 * 32);
+        ASSERT_NE(ptr, nullptr);
     }
 
-    std::string unaligned_file_;
-    std::string file_4k_;
-    std::string file_32k_;
-    FiemapUniquePtr fptr_unaligned;
-    FiemapUniquePtr fptr_4k;
-    FiemapUniquePtr fptr_32k;
-};
+    auto ptr = SplitFiemap::Open(testfile);
+    ASSERT_NE(ptr, nullptr);
 
-TEST_F(TestExistingFile, ErrorChecks) {
-    EXPECT_EQ(fptr_unaligned, nullptr);
-    EXPECT_NE(fptr_4k, nullptr);
-    EXPECT_NE(fptr_32k, nullptr);
+    auto extents = ptr->extents();
+    ASSERT_GE(extents.size(), 24);
+}
 
-    EXPECT_EQ(fptr_4k->size(), 4096);
-    EXPECT_EQ(fptr_32k->size(), 32768);
-    EXPECT_GT(fptr_4k->extents().size(), 0);
-    EXPECT_GT(fptr_32k->extents().size(), 0);
+TEST_F(SplitFiemapTest, DeleteOnFail) {
+    auto ptr = SplitFiemap::Create(testfile, 1024 * 1024 * 10, 1);
+    ASSERT_EQ(ptr, nullptr);
+
+    std::string first_file = testfile + ".0001";
+    ASSERT_NE(access(first_file.c_str(), F_OK), 0);
+    ASSERT_EQ(errno, ENOENT);
+    ASSERT_NE(access(testfile.c_str(), F_OK), 0);
+    ASSERT_EQ(errno, ENOENT);
 }
 
 class VerifyBlockWritesExt4 : public ::testing::Test {
@@ -263,17 +318,41 @@
     std::string fs_path;
 };
 
+bool DetermineBlockSize() {
+    struct statfs s;
+    if (statfs(gTestDir.c_str(), &s)) {
+        std::cerr << "Could not call statfs: " << strerror(errno) << "\n";
+        return false;
+    }
+    if (!s.f_bsize) {
+        std::cerr << "Invalid block size: " << s.f_bsize << "\n";
+        return false;
+    }
+
+    gBlockSize = s.f_bsize;
+    return true;
+}
+
 int main(int argc, char** argv) {
     ::testing::InitGoogleTest(&argc, argv);
     if (argc <= 1) {
-        cerr << "Filepath with its bdev path must be provided as follows:" << endl;
-        cerr << "  $ fiemap_writer_test </dev/block/XXXX" << endl;
-        cerr << "  where, /dev/block/XXX is the block device where the file resides" << endl;
+        cerr << "Usage: <test_dir> [file_size]\n";
+        cerr << "\n";
+        cerr << "Note: test_dir must be a writable directory.\n";
         exit(EXIT_FAILURE);
     }
     ::android::base::InitLogging(argv, ::android::base::StderrLogger);
 
-    testbdev = argv[1];
+    std::string tempdir = argv[1] + "/XXXXXX"s;
+    if (!mkdtemp(tempdir.data())) {
+        cerr << "unable to create tempdir on " << argv[1] << "\n";
+        exit(EXIT_FAILURE);
+    }
+    if (!android::base::Realpath(tempdir, &gTestDir)) {
+        cerr << "unable to find realpath for " << tempdir;
+        exit(EXIT_FAILURE);
+    }
+
     if (argc > 2) {
         testfile_size = strtoull(argv[2], NULL, 0);
         if (testfile_size == ULLONG_MAX) {
@@ -281,5 +360,14 @@
         }
     }
 
-    return RUN_ALL_TESTS();
+    if (!DetermineBlockSize()) {
+        exit(EXIT_FAILURE);
+    }
+
+    auto result = RUN_ALL_TESTS();
+
+    std::string cmd = "rm -rf " + gTestDir;
+    system(cmd.c_str());
+
+    return result;
 }
diff --git a/fs_mgr/libfiemap_writer/include/libfiemap_writer/fiemap_writer.h b/fs_mgr/libfiemap_writer/include/libfiemap_writer/fiemap_writer.h
index edbae77..831bc75 100644
--- a/fs_mgr/libfiemap_writer/include/libfiemap_writer/fiemap_writer.h
+++ b/fs_mgr/libfiemap_writer/include/libfiemap_writer/fiemap_writer.h
@@ -41,6 +41,9 @@
     // invoked, if create is true, while the file is being initialized. It receives the bytes
     // written and the number of total bytes. If the callback returns false, the operation will
     // fail.
+    //
+    // Note: when create is true, the file size will be aligned up to the nearest file system
+    // block.
     static FiemapUniquePtr Open(const std::string& file_path, uint64_t file_size,
                                 bool create = true,
                                 std::function<bool(uint64_t, uint64_t)> progress = {});
@@ -57,10 +60,12 @@
     // FiemapWriter::Open).
     static bool HasPinnedExtents(const std::string& file_path);
 
-    // The counter part of Write(). It is an error for the offset to be unaligned with
-    // the block device's block size.
-    // In case of error, the contents of buffer MUST be discarded.
-    bool Read(off64_t off, uint8_t* buffer, uint64_t size);
+    // Returns the underlying block device of a file. This will look past device-mapper layers.
+    // If an intermediate device-mapper layer would not maintain a 1:1 mapping (i.e. is a non-
+    // trivial dm-linear), then this will fail. If device-mapper nodes are encountered, then
+    // |uses_dm| will be set to true.
+    static bool GetBlockDeviceForFile(const std::string& file_path, std::string* bdev_path,
+                                      bool* uses_dm = nullptr);
 
     ~FiemapWriter() = default;
 
@@ -69,6 +74,7 @@
     const std::string& bdev_path() const { return bdev_path_; };
     uint64_t block_size() const { return block_size_; };
     const std::vector<struct fiemap_extent>& extents() { return extents_; };
+    uint32_t fs_type() const { return fs_type_; }
 
     // Non-copyable & Non-movable
     FiemapWriter(const FiemapWriter&) = delete;
diff --git a/fs_mgr/libfiemap_writer/include/libfiemap_writer/split_fiemap_writer.h b/fs_mgr/libfiemap_writer/include/libfiemap_writer/split_fiemap_writer.h
new file mode 100644
index 0000000..765cc84
--- /dev/null
+++ b/fs_mgr/libfiemap_writer/include/libfiemap_writer/split_fiemap_writer.h
@@ -0,0 +1,79 @@
+/*
+ * Copyright (C) 2019 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#pragma once
+
+#include <stdint.h>
+
+#include <functional>
+#include <memory>
+#include <string>
+#include <vector>
+
+#include "fiemap_writer.h"
+
+namespace android {
+namespace fiemap_writer {
+
+// Wrapper around FiemapWriter that is able to split images across files if
+// necessary.
+class SplitFiemap final {
+  public:
+    using ProgressCallback = std::function<bool(uint64_t, uint64_t)>;
+
+    // Create a new split fiemap file. If |max_piece_size| is 0, the number of
+    // pieces will be determined automatically by detecting the filesystem.
+    // Otherwise, the file will be split evenly (with the remainder in the
+    // final file).
+    static std::unique_ptr<SplitFiemap> Create(const std::string& file_path, uint64_t file_size,
+                                               uint64_t max_piece_size,
+                                               ProgressCallback progress = {});
+
+    // Open an existing split fiemap file.
+    static std::unique_ptr<SplitFiemap> Open(const std::string& file_path);
+
+    ~SplitFiemap();
+
+    // Return a list of all files created for a split file.
+    static bool GetSplitFileList(const std::string& file_path, std::vector<std::string>* list);
+
+    // Destroy all components of a split file. If the root file does not exist,
+    // this returns true and does not report an error.
+    static bool RemoveSplitFiles(const std::string& file_path, std::string* message = nullptr);
+
+    const std::vector<struct fiemap_extent>& extents();
+    uint32_t block_size() const;
+    uint64_t size() const { return total_size_; }
+
+    // Non-copyable & Non-movable
+    SplitFiemap(const SplitFiemap&) = delete;
+    SplitFiemap& operator=(const SplitFiemap&) = delete;
+    SplitFiemap& operator=(SplitFiemap&&) = delete;
+    SplitFiemap(SplitFiemap&&) = delete;
+
+  private:
+    SplitFiemap() = default;
+    void AddFile(FiemapUniquePtr&& file);
+
+    bool creating_ = false;
+    std::string list_file_;
+    std::vector<FiemapUniquePtr> files_;
+    std::vector<struct fiemap_extent> extents_;
+    uint64_t total_size_ = 0;
+};
+
+}  // namespace fiemap_writer
+}  // namespace android
diff --git a/fs_mgr/libfiemap_writer/split_fiemap_writer.cpp b/fs_mgr/libfiemap_writer/split_fiemap_writer.cpp
new file mode 100644
index 0000000..1f80370
--- /dev/null
+++ b/fs_mgr/libfiemap_writer/split_fiemap_writer.cpp
@@ -0,0 +1,214 @@
+/*
+ * Copyright (C) 2019 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <libfiemap_writer/split_fiemap_writer.h>
+
+#include <fcntl.h>
+#include <stdint.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#include <memory>
+#include <string>
+#include <vector>
+
+#include <android-base/file.h>
+#include <android-base/logging.h>
+#include <android-base/stringprintf.h>
+#include <android-base/strings.h>
+#include <android-base/unique_fd.h>
+
+#include "utility.h"
+
+namespace android {
+namespace fiemap_writer {
+
+using android::base::unique_fd;
+
+// We use a four-digit suffix at the end of filenames.
+static const size_t kMaxFilePieces = 500;
+
+std::unique_ptr<SplitFiemap> SplitFiemap::Create(const std::string& file_path, uint64_t file_size,
+                                                 uint64_t max_piece_size,
+                                                 ProgressCallback progress) {
+    if (!file_size) {
+        LOG(ERROR) << "Cannot create a fiemap for a 0-length file: " << file_path;
+        return nullptr;
+    }
+
+    if (!max_piece_size) {
+        max_piece_size = DetermineMaximumFileSize(file_path);
+        if (!max_piece_size) {
+            LOG(ERROR) << "Could not determine maximum file size for " << file_path;
+            return nullptr;
+        }
+    }
+
+    // Call |progress| only when the total percentage would significantly change.
+    int permille = -1;
+    uint64_t total_bytes_written = 0;
+    auto on_progress = [&](uint64_t written, uint64_t) -> bool {
+        uint64_t actual_written = total_bytes_written + written;
+        int new_permille = (actual_written * 1000) / file_size;
+        if (new_permille != permille && actual_written < file_size) {
+            if (progress && !progress(actual_written, file_size)) {
+                return false;
+            }
+            permille = new_permille;
+        }
+        return true;
+    };
+
+    std::unique_ptr<SplitFiemap> out(new SplitFiemap());
+    out->creating_ = true;
+    out->list_file_ = file_path;
+
+    // Create the split files.
+    uint64_t remaining_bytes = file_size;
+    while (remaining_bytes) {
+        if (out->files_.size() >= kMaxFilePieces) {
+            LOG(ERROR) << "Requested size " << file_size << " created too many split files";
+            return nullptr;
+        }
+        std::string chunk_path =
+                android::base::StringPrintf("%s.%04d", file_path.c_str(), (int)out->files_.size());
+        uint64_t chunk_size = std::min(max_piece_size, remaining_bytes);
+        auto writer = FiemapWriter::Open(chunk_path, chunk_size, true, on_progress);
+        if (!writer) {
+            return nullptr;
+        }
+
+        // To make sure the alignment doesn't create too much inconsistency, we
+        // account the *actual* size, not the requested size.
+        total_bytes_written += writer->size();
+        remaining_bytes -= writer->size();
+
+        out->AddFile(std::move(writer));
+    }
+
+    // Create the split file list.
+    unique_fd fd(open(out->list_file_.c_str(), O_CREAT | O_WRONLY | O_CLOEXEC, 0660));
+    if (fd < 0) {
+        PLOG(ERROR) << "Failed to open " << file_path;
+        return nullptr;
+    }
+
+    for (const auto& writer : out->files_) {
+        std::string line = android::base::Basename(writer->file_path()) + "\n";
+        if (!android::base::WriteFully(fd, line.data(), line.size())) {
+            PLOG(ERROR) << "Write failed " << file_path;
+            return nullptr;
+        }
+    }
+
+    // Unset this bit, so we don't unlink on destruction.
+    out->creating_ = false;
+    return out;
+}
+
+std::unique_ptr<SplitFiemap> SplitFiemap::Open(const std::string& file_path) {
+    std::vector<std::string> files;
+    if (!GetSplitFileList(file_path, &files)) {
+        return nullptr;
+    }
+
+    std::unique_ptr<SplitFiemap> out(new SplitFiemap());
+    out->list_file_ = file_path;
+
+    for (const auto& file : files) {
+        auto writer = FiemapWriter::Open(file, 0, false);
+        if (!writer) {
+            // Error was logged in Open().
+            return nullptr;
+        }
+        out->AddFile(std::move(writer));
+    }
+    return out;
+}
+
+bool SplitFiemap::GetSplitFileList(const std::string& file_path, std::vector<std::string>* list) {
+    // This is not the most efficient thing, but it is simple and recovering
+    // the fiemap/fibmap is much more expensive.
+    std::string contents;
+    if (!android::base::ReadFileToString(file_path, &contents, true)) {
+        PLOG(ERROR) << "Error reading file: " << file_path;
+        return false;
+    }
+
+    std::vector<std::string> names = android::base::Split(contents, "\n");
+    std::string dir = android::base::Dirname(file_path);
+    for (const auto& name : names) {
+        if (!name.empty()) {
+            list->emplace_back(dir + "/" + name);
+        }
+    }
+    return true;
+}
+
+bool SplitFiemap::RemoveSplitFiles(const std::string& file_path, std::string* message) {
+    // Early exit if this does not exist, and do not report an error.
+    if (access(file_path.c_str(), F_OK) && errno == ENOENT) {
+        return true;
+    }
+
+    bool ok = true;
+    std::vector<std::string> files;
+    if (GetSplitFileList(file_path, &files)) {
+        for (const auto& file : files) {
+            ok &= android::base::RemoveFileIfExists(file, message);
+        }
+    }
+    ok &= android::base::RemoveFileIfExists(file_path, message);
+    return ok;
+}
+
+const std::vector<struct fiemap_extent>& SplitFiemap::extents() {
+    if (extents_.empty()) {
+        for (const auto& file : files_) {
+            const auto& extents = file->extents();
+            extents_.insert(extents_.end(), extents.begin(), extents.end());
+        }
+    }
+    return extents_;
+}
+
+SplitFiemap::~SplitFiemap() {
+    if (!creating_) {
+        return;
+    }
+
+    // We failed to finish creating, so unlink everything.
+    unlink(list_file_.c_str());
+    for (auto&& file : files_) {
+        std::string path = file->file_path();
+        file = nullptr;
+
+        unlink(path.c_str());
+    }
+}
+
+void SplitFiemap::AddFile(FiemapUniquePtr&& file) {
+    total_size_ += file->size();
+    files_.emplace_back(std::move(file));
+}
+
+uint32_t SplitFiemap::block_size() const {
+    return files_[0]->block_size();
+}
+
+}  // namespace fiemap_writer
+}  // namespace android
diff --git a/fs_mgr/libfiemap_writer/utility.cpp b/fs_mgr/libfiemap_writer/utility.cpp
new file mode 100644
index 0000000..192ec16
--- /dev/null
+++ b/fs_mgr/libfiemap_writer/utility.cpp
@@ -0,0 +1,66 @@
+/*
+ * Copyright (C) 2019 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "utility.h"
+
+#include <stdint.h>
+#include <sys/vfs.h>
+#include <unistd.h>
+
+#include <android-base/logging.h>
+#include <libfiemap_writer/fiemap_writer.h>
+
+namespace android {
+namespace fiemap_writer {
+
+uint64_t DetermineMaximumFileSize(const std::string& file_path) {
+    // Create the smallest file possible (one block).
+    auto writer = FiemapWriter::Open(file_path, 1);
+    if (!writer) {
+        return 0;
+    }
+
+    uint64_t result = 0;
+    switch (writer->fs_type()) {
+        case EXT4_SUPER_MAGIC:
+            // The minimum is 16GiB, so just report that. If we wanted we could parse the
+            // superblock and figure out if 64-bit support is enabled.
+            result = 17179869184ULL;
+            break;
+        case F2FS_SUPER_MAGIC:
+            // Formula is from https://www.kernel.org/doc/Documentation/filesystems/f2fs.txt
+            // 4KB * (923 + 2 * 1018 + 2 * 1018 * 1018 + 1018 * 1018 * 1018) := 3.94TB.
+            result = 4329690886144ULL;
+            break;
+        case MSDOS_SUPER_MAGIC:
+            // 4GB-1, which we want aligned to the block size.
+            result = 4294967295;
+            result -= (result % writer->block_size());
+            break;
+        default:
+            LOG(ERROR) << "Unknown file system type: " << writer->fs_type();
+            break;
+    }
+
+    // Close and delete the temporary file.
+    writer = nullptr;
+    unlink(file_path.c_str());
+
+    return result;
+}
+
+}  // namespace fiemap_writer
+}  // namespace android
diff --git a/fs_mgr/libfiemap_writer/utility.h b/fs_mgr/libfiemap_writer/utility.h
new file mode 100644
index 0000000..2d418da
--- /dev/null
+++ b/fs_mgr/libfiemap_writer/utility.h
@@ -0,0 +1,30 @@
+/*
+ * Copyright (C) 2019 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#pragma once
+
+#include <string>
+
+namespace android {
+namespace fiemap_writer {
+
+// Given a file that will be created, determine the maximum size its containing
+// filesystem allows. Note this is a theoretical maximum size; free space is
+// ignored entirely.
+uint64_t DetermineMaximumFileSize(const std::string& file_path);
+
+}  // namespace fiemap_writer
+}  // namespace android
diff --git a/fs_mgr/libfs_avb/avb_util.cpp b/fs_mgr/libfs_avb/avb_util.cpp
index fa9080e..f4e4d4e 100644
--- a/fs_mgr/libfs_avb/avb_util.cpp
+++ b/fs_mgr/libfs_avb/avb_util.cpp
@@ -28,12 +28,26 @@
 #include "util.h"
 
 using android::base::Basename;
+using android::base::ReadFileToString;
 using android::base::StartsWith;
 using android::base::unique_fd;
 
 namespace android {
 namespace fs_mgr {
 
+std::string GetAvbPropertyDescriptor(const std::string& key,
+                                     const std::vector<VBMetaData>& vbmeta_images) {
+    size_t value_size;
+    for (const auto& vbmeta : vbmeta_images) {
+        const char* value = avb_property_lookup(vbmeta.data(), vbmeta.size(), key.data(),
+                                                key.size(), &value_size);
+        if (value != nullptr) {
+            return {value, value_size};
+        }
+    }
+    return "";
+}
+
 // Constructs dm-verity arguments for sending DM_TABLE_LOAD ioctl to kernel.
 // See the following link for more details:
 // https://gitlab.com/cryptsetup/cryptsetup/wikis/DMVerity
@@ -298,7 +312,8 @@
     return footer;
 }
 
-bool VerifyPublicKeyBlob(const uint8_t* key, size_t length, const std::string& expected_key_blob) {
+bool ValidatePublicKeyBlob(const uint8_t* key, size_t length,
+                           const std::string& expected_key_blob) {
     if (expected_key_blob.empty()) {  // no expectation of the key, return true.
         return true;
     }
@@ -311,6 +326,21 @@
     return false;
 }
 
+bool ValidatePublicKeyBlob(const std::string& key_blob_to_validate,
+                           const std::vector<std::string>& allowed_key_paths) {
+    std::string allowed_key_blob;
+    if (key_blob_to_validate.empty()) {
+        LWARNING << "Failed to validate an empty key";
+        return false;
+    }
+    for (const auto& path : allowed_key_paths) {
+        if (ReadFileToString(path, &allowed_key_blob)) {
+            if (key_blob_to_validate == allowed_key_blob) return true;
+        }
+    }
+    return false;
+}
+
 VBMetaVerifyResult VerifyVBMetaSignature(const VBMetaData& vbmeta,
                                          const std::string& expected_public_key_blob,
                                          std::string* out_public_key_data) {
@@ -334,7 +364,7 @@
                        << ": Error verifying vbmeta image: failed to get public key";
                 return VBMetaVerifyResult::kError;
             }
-            if (!VerifyPublicKeyBlob(pk_data, pk_len, expected_public_key_blob)) {
+            if (!ValidatePublicKeyBlob(pk_data, pk_len, expected_public_key_blob)) {
                 LERROR << vbmeta.partition() << ": Error verifying vbmeta image: public key used to"
                        << " sign data does not match key in chain descriptor";
                 return VBMetaVerifyResult::kErrorVerification;
diff --git a/fs_mgr/libfs_avb/avb_util.h b/fs_mgr/libfs_avb/avb_util.h
index 9babd88..09c786a 100644
--- a/fs_mgr/libfs_avb/avb_util.h
+++ b/fs_mgr/libfs_avb/avb_util.h
@@ -37,6 +37,9 @@
         : partition_name(chain_partition_name), public_key_blob(chain_public_key_blob) {}
 };
 
+std::string GetAvbPropertyDescriptor(const std::string& key,
+                                     const std::vector<VBMetaData>& vbmeta_images);
+
 // AvbHashtreeDescriptor to dm-verity table setup.
 std::unique_ptr<FsAvbHashtreeDescriptor> GetHashtreeDescriptor(
         const std::string& partition_name, const std::vector<VBMetaData>& vbmeta_images);
@@ -75,7 +78,10 @@
                                          const std::string& expected_public_key_blob,
                                          std::string* out_public_key_data);
 
-bool VerifyPublicKeyBlob(const uint8_t* key, size_t length, const std::string& expected_key_blob);
+bool ValidatePublicKeyBlob(const uint8_t* key, size_t length, const std::string& expected_key_blob);
+
+bool ValidatePublicKeyBlob(const std::string& key_blob_to_validate,
+                           const std::vector<std::string>& expected_key_paths);
 
 // Detects if whether a partition contains a rollback image.
 bool RollbackDetected(const std::string& partition_name, uint64_t rollback_index);
diff --git a/fs_mgr/libfs_avb/fs_avb.cpp b/fs_mgr/libfs_avb/fs_avb.cpp
index 938e149..f0767dc 100644
--- a/fs_mgr/libfs_avb/fs_avb.cpp
+++ b/fs_mgr/libfs_avb/fs_avb.cpp
@@ -29,6 +29,7 @@
 #include <android-base/file.h>
 #include <android-base/parseint.h>
 #include <android-base/stringprintf.h>
+#include <android-base/strings.h>
 #include <libavb/libavb.h>
 #include <libdm/dm.h>
 
@@ -40,6 +41,7 @@
 using android::base::Basename;
 using android::base::ParseUint;
 using android::base::ReadFileToString;
+using android::base::Split;
 using android::base::StringPrintf;
 
 namespace android {
@@ -263,6 +265,68 @@
     return avb_handle;
 }
 
+AvbUniquePtr AvbHandle::LoadAndVerifyVbmeta(const FstabEntry& fstab_entry) {
+    if (fstab_entry.avb_keys.empty()) {
+        LERROR << "avb_keys=/path/to/key(s) is missing for " << fstab_entry.mount_point;
+        return nullptr;
+    }
+
+    // Binds allow_verification_error and rollback_protection to device unlock state.
+    bool allow_verification_error = IsDeviceUnlocked();
+    bool rollback_protection = !allow_verification_error;
+
+    std::string public_key_data;
+    bool verification_disabled = false;
+    VBMetaVerifyResult verify_result = VBMetaVerifyResult::kError;
+    std::unique_ptr<VBMetaData> vbmeta = LoadAndVerifyVbmetaByPath(
+            fstab_entry.blk_device, "" /* partition_name, no need for a standalone path */,
+            "" /* expected_public_key_blob, */, allow_verification_error, rollback_protection,
+            false /* not is_chained_vbmeta */, &public_key_data, &verification_disabled,
+            &verify_result);
+
+    if (!vbmeta) {
+        LERROR << "Failed to load vbmeta: " << fstab_entry.blk_device;
+        return nullptr;
+    }
+
+    AvbUniquePtr avb_handle(new AvbHandle());
+    if (!avb_handle) {
+        LERROR << "Failed to allocate AvbHandle";
+        return nullptr;
+    }
+    avb_handle->vbmeta_images_.emplace_back(std::move(*vbmeta));
+
+    switch (verify_result) {
+        case VBMetaVerifyResult::kSuccess:
+            avb_handle->status_ = AvbHandleStatus::kSuccess;
+            break;
+        case VBMetaVerifyResult::kErrorVerification:
+            avb_handle->status_ = AvbHandleStatus::kVerificationError;
+            break;
+        default:
+            LERROR << "LoadAndVerifyVbmetaByPath failed, result: " << verify_result;
+            return nullptr;
+    }
+
+    if (!ValidatePublicKeyBlob(public_key_data, Split(fstab_entry.avb_keys, ":"))) {
+        avb_handle->status_ = AvbHandleStatus::kVerificationError;
+        LWARNING << "Found unknown public key used to sign " << fstab_entry.mount_point;
+        if (!allow_verification_error) {
+            LERROR << "Unknown public key is not allowed";
+            return nullptr;
+        }
+    }
+
+    if (verification_disabled) {
+        LINFO << "AVB verification disabled on: " << fstab_entry.mount_point;
+        avb_handle->status_ = AvbHandleStatus::kVerificationDisabled;
+    }
+
+    LINFO << "Returning avb_handle for '" << fstab_entry.mount_point
+          << "' with status: " << avb_handle->status_;
+    return avb_handle;
+}
+
 AvbUniquePtr AvbHandle::LoadAndVerifyVbmeta() {
     // Loads inline vbmeta images, starting from /vbmeta.
     return LoadAndVerifyVbmeta("vbmeta", fs_mgr_get_slot_suffix(), fs_mgr_get_other_slot_suffix(),
@@ -358,52 +422,12 @@
 
 AvbHashtreeResult AvbHandle::SetUpStandaloneAvbHashtree(FstabEntry* fstab_entry,
                                                         bool wait_for_verity_dev) {
-    if (fstab_entry->avb_key.empty()) {
-        LERROR << "avb_key=/path/to/key is missing for " << fstab_entry->mount_point;
+    auto avb_handle = LoadAndVerifyVbmeta(*fstab_entry);
+    if (!avb_handle) {
         return AvbHashtreeResult::kFail;
     }
 
-    // Binds allow_verification_error and rollback_protection to device unlock state.
-    bool allow_verification_error = IsDeviceUnlocked();
-    bool rollback_protection = !allow_verification_error;
-
-    std::string expected_key_blob;
-    if (!ReadFileToString(fstab_entry->avb_key, &expected_key_blob)) {
-        if (!allow_verification_error) {
-            LERROR << "Failed to load avb_key: " << fstab_entry->avb_key
-                   << " for mount point: " << fstab_entry->mount_point;
-            return AvbHashtreeResult::kFail;
-        }
-        LWARNING << "Allowing no expected key blob when verification error is permitted";
-        expected_key_blob.clear();
-    }
-
-    bool verification_disabled = false;
-    std::unique_ptr<VBMetaData> vbmeta = LoadAndVerifyVbmetaByPath(
-            fstab_entry->blk_device, "" /* partition_name, no need for a standalone path */,
-            expected_key_blob, allow_verification_error, rollback_protection,
-            false /* not is_chained_vbmeta */, nullptr /* out_public_key_data */,
-            &verification_disabled, nullptr /* out_verify_result */);
-
-    if (!vbmeta) {
-        LERROR << "Failed to load vbmeta: " << fstab_entry->blk_device;
-        return AvbHashtreeResult::kFail;
-    }
-
-    if (verification_disabled) {
-        LINFO << "AVB verification disabled on: " << fstab_entry->mount_point;
-        return AvbHashtreeResult::kDisabled;
-    }
-
-    // Puts the vbmeta into a vector, for LoadAvbHashtreeToEnableVerity() to use.
-    std::vector<VBMetaData> vbmeta_images;
-    vbmeta_images.emplace_back(std::move(*vbmeta));
-    if (!LoadAvbHashtreeToEnableVerity(fstab_entry, wait_for_verity_dev, vbmeta_images,
-                                       fs_mgr_get_slot_suffix(), fs_mgr_get_other_slot_suffix())) {
-        return AvbHashtreeResult::kFail;
-    }
-
-    return AvbHashtreeResult::kSuccess;
+    return avb_handle->SetUpAvbHashtree(fstab_entry, wait_for_verity_dev);
 }
 
 AvbHashtreeResult AvbHandle::SetUpAvbHashtree(FstabEntry* fstab_entry, bool wait_for_verity_dev) {
@@ -425,5 +449,19 @@
     return AvbHashtreeResult::kSuccess;
 }
 
+std::string AvbHandle::GetSecurityPatchLevel(const FstabEntry& fstab_entry) const {
+    if (vbmeta_images_.size() < 1) {
+        return "";
+    }
+    std::string avb_partition_name = DeriveAvbPartitionName(fstab_entry, fs_mgr_get_slot_suffix(),
+                                                            fs_mgr_get_other_slot_suffix());
+    auto avb_prop_name = "com.android.build." + avb_partition_name + ".security_patch";
+    return GetAvbPropertyDescriptor(avb_prop_name, vbmeta_images_);
+}
+
+bool AvbHandle::IsDeviceUnlocked() {
+    return android::fs_mgr::IsDeviceUnlocked();
+}
+
 }  // namespace fs_mgr
 }  // namespace android
diff --git a/fs_mgr/libfs_avb/include/fs_avb/fs_avb.h b/fs_mgr/libfs_avb/include/fs_avb/fs_avb.h
index d026722..7127fa6 100644
--- a/fs_mgr/libfs_avb/include/fs_avb/fs_avb.h
+++ b/fs_mgr/libfs_avb/include/fs_avb/fs_avb.h
@@ -85,6 +85,8 @@
     // TODO(bowgotsai): remove Open() and switch to LoadAndVerifyVbmeta().
     static AvbUniquePtr Open();                 // loads inline vbmeta, via libavb.
     static AvbUniquePtr LoadAndVerifyVbmeta();  // loads inline vbmeta.
+    static AvbUniquePtr LoadAndVerifyVbmeta(
+            const FstabEntry& fstab_entry);     // loads offline vbmeta.
     static AvbUniquePtr LoadAndVerifyVbmeta(    // loads offline vbmeta.
             const std::string& partition_name, const std::string& ab_suffix,
             const std::string& ab_other_suffix, const std::string& expected_public_key,
@@ -108,6 +110,10 @@
     static AvbHashtreeResult SetUpStandaloneAvbHashtree(FstabEntry* fstab_entry,
                                                         bool wait_for_verity_dev = true);
 
+    static bool IsDeviceUnlocked();
+
+    std::string GetSecurityPatchLevel(const FstabEntry& fstab_entry) const;
+
     const std::string& avb_version() const { return avb_version_; }
     const VBMetaInfo& vbmeta_info() const { return vbmeta_info_; }
     AvbHandleStatus status() const { return status_; }
diff --git a/fs_mgr/libfs_avb/tests/avb_util_test.cpp b/fs_mgr/libfs_avb/tests/avb_util_test.cpp
index 835410f..0d342d3 100644
--- a/fs_mgr/libfs_avb/tests/avb_util_test.cpp
+++ b/fs_mgr/libfs_avb/tests/avb_util_test.cpp
@@ -30,13 +30,14 @@
 using android::fs_mgr::DeriveAvbPartitionName;
 using android::fs_mgr::FstabEntry;
 using android::fs_mgr::GetAvbFooter;
+using android::fs_mgr::GetAvbPropertyDescriptor;
 using android::fs_mgr::GetChainPartitionInfo;
 using android::fs_mgr::GetTotalSize;
 using android::fs_mgr::LoadAndVerifyVbmetaByPartition;
 using android::fs_mgr::LoadAndVerifyVbmetaByPath;
+using android::fs_mgr::ValidatePublicKeyBlob;
 using android::fs_mgr::VBMetaData;
 using android::fs_mgr::VBMetaVerifyResult;
-using android::fs_mgr::VerifyPublicKeyBlob;
 using android::fs_mgr::VerifyVBMetaData;
 using android::fs_mgr::VerifyVBMetaSignature;
 
@@ -268,6 +269,67 @@
     EXPECT_EQ(nullptr, footer);
 }
 
+TEST_F(AvbUtilTest, GetAvbPropertyDescriptor_Basic) {
+    // Makes a vbmeta.img with some properties.
+    GenerateVBMetaImage("vbmeta.img", "SHA256_RSA4096", 0, data_dir_.Append("testkey_rsa4096.pem"),
+                        {}, /* include_descriptor_image_paths */
+                        {}, /* chain_partitions */
+                        "--prop foo:android "
+                        "--prop bar:treble "
+                        "--internal_release_string \"unit test\" ");
+    auto vbmeta = LoadVBMetaData("vbmeta.img");
+
+    // Puts the vbmeta into a vector, for GetAvbPropertyDescriptor to use.
+    std::vector<VBMetaData> vbmeta_images;
+    vbmeta_images.emplace_back(std::move(vbmeta));
+
+    EXPECT_EQ("android", GetAvbPropertyDescriptor("foo", vbmeta_images));
+    EXPECT_EQ("treble", GetAvbPropertyDescriptor("bar", vbmeta_images));
+    EXPECT_EQ("", GetAvbPropertyDescriptor("non-existent", vbmeta_images));
+}
+
+TEST_F(AvbUtilTest, GetAvbPropertyDescriptor_SecurityPatchLevel) {
+    // Generates a raw boot.img
+    const size_t boot_image_size = 5 * 1024 * 1024;
+    const size_t boot_partition_size = 10 * 1024 * 1024;
+    base::FilePath boot_path = GenerateImage("boot.img", boot_image_size);
+    // Adds AVB Hash Footer.
+    AddAvbFooter(boot_path, "hash", "boot", boot_partition_size, "SHA256_RSA2048", 10,
+                 data_dir_.Append("testkey_rsa2048.pem"), "d00df00d",
+                 "--internal_release_string \"unit test\"");
+
+    // Generates a raw system.img, use a smaller size to speed-up unit test.
+    const size_t system_image_size = 10 * 1024 * 1024;
+    const size_t system_partition_size = 15 * 1024 * 1024;
+    base::FilePath system_path = GenerateImage("system.img", system_image_size);
+    // Adds AVB Hashtree Footer.
+    AddAvbFooter(system_path, "hashtree", "system", system_partition_size, "SHA512_RSA4096", 20,
+                 data_dir_.Append("testkey_rsa4096.pem"), "d00df00d",
+                 "--prop com.android.build.system.security_patch:2019-04-05 "
+                 "--internal_release_string \"unit test\"");
+
+    // Generates chain partition descriptors.
+    base::FilePath rsa4096_public_key =
+            ExtractPublicKeyAvb(data_dir_.Append("testkey_rsa4096.pem"));
+
+    // Makes a vbmeta.img including the 'system' chained descriptor.
+    GenerateVBMetaImage("vbmeta.img", "SHA256_RSA4096", 0, data_dir_.Append("testkey_rsa4096.pem"),
+                        {boot_path},                         /* include_descriptor_image_paths */
+                        {{"system", 3, rsa4096_public_key}}, /* chain_partitions */
+                        "--internal_release_string \"unit test\"");
+
+    auto vbmeta = LoadVBMetaData("vbmeta.img");
+    auto system_vbmeta = ExtractAndLoadVBMetaData(system_path, "system-vbmeta.img");
+
+    // Puts the vbmeta into a vector, for GetAvbPropertyDescriptor to use.
+    std::vector<VBMetaData> vbmeta_images;
+    vbmeta_images.emplace_back(std::move(vbmeta));
+    vbmeta_images.emplace_back(std::move(system_vbmeta));
+
+    EXPECT_EQ("2019-04-05",
+              GetAvbPropertyDescriptor("com.android.build.system.security_patch", vbmeta_images));
+}
+
 TEST_F(AvbUtilTest, GetVBMetaHeader) {
     // Generates a raw boot.img
     const size_t image_size = 5 * 1024 * 1024;
@@ -353,7 +415,7 @@
     EXPECT_EQ(content_padding.size() - padding.size(), vbmeta_padding.size());
 }
 
-TEST_F(AvbUtilTest, VerifyPublicKeyBlob) {
+TEST_F(AvbUtilTest, ValidatePublicKeyBlob) {
     // Generates a raw key.bin
     const size_t key_size = 2048;
     base::FilePath key_path = GenerateImage("key.bin", key_size);
@@ -363,12 +425,12 @@
 
     std::string expected_key_blob;
     EXPECT_TRUE(base::ReadFileToString(key_path, &expected_key_blob));
-    EXPECT_TRUE(VerifyPublicKeyBlob(key_data, key_size, expected_key_blob));
+    EXPECT_TRUE(ValidatePublicKeyBlob(key_data, key_size, expected_key_blob));
 
     key_data[10] ^= 0x80;  // toggles a bit and expects a failure
-    EXPECT_FALSE(VerifyPublicKeyBlob(key_data, key_size, expected_key_blob));
+    EXPECT_FALSE(ValidatePublicKeyBlob(key_data, key_size, expected_key_blob));
     key_data[10] ^= 0x80;  // toggles the bit again, should pass
-    EXPECT_TRUE(VerifyPublicKeyBlob(key_data, key_size, expected_key_blob));
+    EXPECT_TRUE(ValidatePublicKeyBlob(key_data, key_size, expected_key_blob));
 }
 
 TEST_F(AvbUtilTest, VerifyEmptyPublicKeyBlob) {
@@ -380,7 +442,37 @@
     EXPECT_EQ(key_size, base::ReadFile(key_path, (char*)key_data, key_size));
 
     std::string expected_key_blob = "";  // empty means no expectation, thus return true.
-    EXPECT_TRUE(VerifyPublicKeyBlob(key_data, key_size, expected_key_blob));
+    EXPECT_TRUE(ValidatePublicKeyBlob(key_data, key_size, expected_key_blob));
+}
+
+TEST_F(AvbUtilTest, ValidatePublicKeyBlob_MultipleAllowedKeys) {
+    base::FilePath rsa2048_public_key =
+            ExtractPublicKeyAvb(data_dir_.Append("testkey_rsa2048.pem"));
+    base::FilePath rsa4096_public_key =
+            ExtractPublicKeyAvb(data_dir_.Append("testkey_rsa4096.pem"));
+    base::FilePath rsa8192_public_key =
+            ExtractPublicKeyAvb(data_dir_.Append("testkey_rsa8192.pem"));
+
+    std::vector<std::string> allowed_key_paths;
+    allowed_key_paths.push_back(rsa2048_public_key.value());
+    allowed_key_paths.push_back(rsa4096_public_key.value());
+
+    std::string expected_key_blob_2048;
+    EXPECT_TRUE(base::ReadFileToString(rsa2048_public_key, &expected_key_blob_2048));
+    std::string expected_key_blob_4096;
+    EXPECT_TRUE(base::ReadFileToString(rsa4096_public_key, &expected_key_blob_4096));
+    std::string expected_key_blob_8192;
+    EXPECT_TRUE(base::ReadFileToString(rsa8192_public_key, &expected_key_blob_8192));
+
+    EXPECT_TRUE(ValidatePublicKeyBlob(expected_key_blob_2048, allowed_key_paths));
+    EXPECT_TRUE(ValidatePublicKeyBlob(expected_key_blob_4096, allowed_key_paths));
+
+    EXPECT_FALSE(ValidatePublicKeyBlob(expected_key_blob_8192, allowed_key_paths));
+    EXPECT_FALSE(ValidatePublicKeyBlob("invalid_content", allowed_key_paths));
+    EXPECT_FALSE(ValidatePublicKeyBlob("", allowed_key_paths));
+
+    allowed_key_paths.push_back(rsa8192_public_key.value());
+    EXPECT_TRUE(ValidatePublicKeyBlob(expected_key_blob_8192, allowed_key_paths));
 }
 
 TEST_F(AvbUtilTest, VerifyVBMetaSignature) {
diff --git a/fs_mgr/libfs_avb/tests/fs_avb_device_test.cpp b/fs_mgr/libfs_avb/tests/fs_avb_device_test.cpp
index fc4eb5f..c8605d7 100644
--- a/fs_mgr/libfs_avb/tests/fs_avb_device_test.cpp
+++ b/fs_mgr/libfs_avb/tests/fs_avb_device_test.cpp
@@ -15,6 +15,7 @@
  */
 
 #include <android-base/properties.h>
+#include <fs_avb/fs_avb.h>
 #include <fs_avb/fs_avb_util.h>
 #include <fstab/fstab.h>
 #include <gtest/gtest.h>
@@ -22,6 +23,8 @@
 #include <sys/types.h>
 #include <unistd.h>
 
+using android::fs_mgr::AvbHandle;
+using android::fs_mgr::AvbHandleStatus;
 using android::fs_mgr::Fstab;
 using android::fs_mgr::FstabEntry;
 using android::fs_mgr::VBMetaData;
@@ -31,7 +34,7 @@
 
 // system vbmeta might not be at the end of /system when dynamic partition is
 // enabled. Therefore, disable it by default.
-TEST(PublicFsAvbDeviceTest, DISABLED_LoadAndVerifyVbmeta_SystemVbmeta) {
+TEST(FsAvbUtilTest, DISABLED_LoadAndVerifyVbmeta_SystemVbmeta) {
     Fstab fstab;
     EXPECT_TRUE(ReadDefaultFstab(&fstab));
 
@@ -51,7 +54,7 @@
     EXPECT_NE("", out_public_key_data);
 }
 
-TEST(PublicFsAvbDeviceTest, GetHashtreeDescriptor_SystemOther) {
+TEST(FsAvbUtilTest, GetHashtreeDescriptor_SystemOther) {
     // Non-A/B device doesn't have system_other partition.
     if (fs_mgr_get_slot_suffix() == "") return;
 
@@ -90,4 +93,55 @@
     EXPECT_NE(nullptr, hashtree_desc);
 }
 
+TEST(AvbHandleTest, LoadAndVerifyVbmeta_SystemOther) {
+    // Non-A/B device doesn't have system_other partition.
+    if (fs_mgr_get_slot_suffix() == "") return;
+
+    // Skip running this test if system_other is a logical partition.
+    // Note that system_other is still a physical partition on "retrofit" devices.
+    if (android::base::GetBoolProperty("ro.boot.dynamic_partitions", false) &&
+        !android::base::GetBoolProperty("ro.boot.dynamic_partitions_retrofit", false)) {
+        return;
+    }
+
+    Fstab fstab;
+    EXPECT_TRUE(ReadFstabFromFile("/system/etc/fstab.postinstall", &fstab));
+
+    // It should have two lines in the fstab, the first for logical system_other,
+    // the other for physical system_other.
+    EXPECT_EQ(2UL, fstab.size());
+
+    // Use the 2nd fstab entry, which is for physical system_other partition.
+    FstabEntry* system_other_entry = &fstab[1];
+    // Assign the default key if it's not specified in the fstab.
+    if (system_other_entry->avb_keys.empty()) {
+        system_other_entry->avb_keys = "/system/etc/security/avb/system_other.avbpubkey";
+    }
+    auto avb_handle = AvbHandle::LoadAndVerifyVbmeta(*system_other_entry);
+    EXPECT_NE(nullptr, avb_handle) << "Failed to load system_other vbmeta. Try 'adb root'?";
+    EXPECT_EQ(AvbHandleStatus::kSuccess, avb_handle->status());
+}
+
+TEST(AvbHandleTest, GetSecurityPatchLevel) {
+    Fstab fstab;
+    EXPECT_TRUE(ReadDefaultFstab(&fstab));
+
+    auto avb_handle = AvbHandle::LoadAndVerifyVbmeta();
+    EXPECT_NE(nullptr, avb_handle) << "Failed to load inline vbmeta. Try 'adb root'?";
+    EXPECT_EQ(AvbHandleStatus::kSuccess, avb_handle->status());
+
+    // Gets security patch level with format: YYYY-MM-DD (e.g., 2019-04-05).
+    FstabEntry* system_entry = GetEntryForMountPoint(&fstab, "/system");
+    EXPECT_NE(nullptr, system_entry);
+    EXPECT_EQ(10UL, avb_handle->GetSecurityPatchLevel(*system_entry).length());
+
+    FstabEntry* vendor_entry = GetEntryForMountPoint(&fstab, "/vendor");
+    EXPECT_NE(nullptr, vendor_entry);
+    EXPECT_EQ(10UL, avb_handle->GetSecurityPatchLevel(*vendor_entry).length());
+
+    FstabEntry* product_entry = GetEntryForMountPoint(&fstab, "/product");
+    EXPECT_NE(nullptr, product_entry);
+    EXPECT_EQ(10UL, avb_handle->GetSecurityPatchLevel(*product_entry).length());
+}
+
 }  // namespace fs_avb_device_test
diff --git a/fs_mgr/liblp/builder.cpp b/fs_mgr/liblp/builder.cpp
index c39fbe7..ebd6997 100644
--- a/fs_mgr/liblp/builder.cpp
+++ b/fs_mgr/liblp/builder.cpp
@@ -550,11 +550,11 @@
 }
 
 bool MetadataBuilder::ValidatePartitionSizeChange(Partition* partition, uint64_t old_size,
-                                                  uint64_t new_size) {
+                                                  uint64_t new_size, bool force_check) {
     PartitionGroup* group = FindGroup(partition->group_name());
     CHECK(group);
 
-    if (new_size <= old_size) {
+    if (!force_check && new_size <= old_size) {
         return true;
     }
 
@@ -861,7 +861,7 @@
     uint64_t aligned_size = AlignTo(requested_size, geometry_.logical_block_size);
     uint64_t old_size = partition->size();
 
-    if (!ValidatePartitionSizeChange(partition, old_size, aligned_size)) {
+    if (!ValidatePartitionSizeChange(partition, old_size, aligned_size, false)) {
         return false;
     }
 
@@ -973,7 +973,12 @@
 
     ImportExtents(partition, metadata, source);
 
-    if (!ValidatePartitionSizeChange(partition, 0, partition->size())) {
+    // Note: we've already increased the partition size by calling
+    // ImportExtents(). In order to figure out the size before that,
+    // we would have to iterate the extents and add up the linear
+    // segments. Instead, we just force ValidatePartitionSizeChange
+    // to check if the current configuration is acceptable.
+    if (!ValidatePartitionSizeChange(partition, partition->size(), partition->size(), true)) {
         partition->RemoveExtents();
         return false;
     }
diff --git a/fs_mgr/liblp/builder_test.cpp b/fs_mgr/liblp/builder_test.cpp
index 69724f8..81305b3 100644
--- a/fs_mgr/liblp/builder_test.cpp
+++ b/fs_mgr/liblp/builder_test.cpp
@@ -835,3 +835,73 @@
     EXPECT_EQ(exported->extents[1].target_data, 4608);
     EXPECT_EQ(exported->extents[1].num_sectors, 1536);
 }
+
+TEST_F(BuilderTest, UpdateSuper) {
+    // Build the on-disk metadata that we saw before flashing.
+    auto builder = MetadataBuilder::New(8145338368ULL, 65536, 3);
+    ASSERT_NE(builder, nullptr);
+
+    ASSERT_TRUE(builder->AddGroup("google_dynamic_partitions_a", 4068474880ULL));
+    ASSERT_TRUE(builder->AddGroup("google_dynamic_partitions_b", 4068474880ULL));
+
+    Partition* partition = builder->AddPartition("system_a", "google_dynamic_partitions_a",
+                                                 LP_PARTITION_ATTR_READONLY);
+    ASSERT_NE(partition, nullptr);
+    ASSERT_TRUE(builder->AddLinearExtent(partition, "super", 1901568, 3608576));
+
+    partition = builder->AddPartition("vendor_a", "google_dynamic_partitions_a",
+                                      LP_PARTITION_ATTR_READONLY);
+    ASSERT_NE(partition, nullptr);
+    ASSERT_TRUE(builder->AddLinearExtent(partition, "super", 1521664, 5510144));
+
+    partition = builder->AddPartition("product_a", "google_dynamic_partitions_a",
+                                      LP_PARTITION_ATTR_READONLY);
+    ASSERT_NE(partition, nullptr);
+    ASSERT_TRUE(builder->AddLinearExtent(partition, "super", 3606528, 2048));
+
+    partition = builder->AddPartition("system_b", "google_dynamic_partitions_b",
+                                      LP_PARTITION_ATTR_READONLY);
+    ASSERT_NE(partition, nullptr);
+    ASSERT_TRUE(builder->AddLinearExtent(partition, "super", 1901568, 7955456));
+
+    partition = builder->AddPartition("vendor_b", "google_dynamic_partitions_b",
+                                      LP_PARTITION_ATTR_READONLY);
+    ASSERT_NE(partition, nullptr);
+    ASSERT_TRUE(builder->AddLinearExtent(partition, "super", 1521664, 9857024));
+
+    partition = builder->AddPartition("product_b", "google_dynamic_partitions_b",
+                                      LP_PARTITION_ATTR_READONLY);
+    ASSERT_NE(partition, nullptr);
+    ASSERT_TRUE(builder->AddLinearExtent(partition, "super", 3606528, 11378688));
+
+    auto on_disk = builder->Export();
+    ASSERT_NE(on_disk, nullptr);
+
+    // Build the super_empty from the new build.
+    builder = MetadataBuilder::New(8145338368ULL, 65536, 3);
+    ASSERT_NE(builder, nullptr);
+
+    ASSERT_TRUE(builder->AddGroup("google_dynamic_partitions_a", 4068474880ULL));
+    ASSERT_TRUE(builder->AddGroup("google_dynamic_partitions_b", 4068474880ULL));
+    ASSERT_NE(builder->AddPartition("system_a", "google_dynamic_partitions_a",
+                                    LP_PARTITION_ATTR_READONLY),
+              nullptr);
+    ASSERT_NE(builder->AddPartition("system_b", "google_dynamic_partitions_b",
+                                    LP_PARTITION_ATTR_READONLY),
+              nullptr);
+    ASSERT_NE(builder->AddPartition("vendor_a", "google_dynamic_partitions_a",
+                                    LP_PARTITION_ATTR_READONLY),
+              nullptr);
+    ASSERT_NE(builder->AddPartition("vendor_b", "google_dynamic_partitions_b",
+                                    LP_PARTITION_ATTR_READONLY),
+              nullptr);
+    ASSERT_NE(builder->AddPartition("product_a", "google_dynamic_partitions_a",
+                                    LP_PARTITION_ATTR_READONLY),
+              nullptr);
+    ASSERT_NE(builder->AddPartition("product_b", "google_dynamic_partitions_b",
+                                    LP_PARTITION_ATTR_READONLY),
+              nullptr);
+
+    std::set<std::string> partitions_to_keep{"system_a", "vendor_a", "product_a"};
+    ASSERT_TRUE(builder->ImportPartitions(*on_disk.get(), partitions_to_keep));
+}
diff --git a/fs_mgr/liblp/include/liblp/builder.h b/fs_mgr/liblp/include/liblp/builder.h
index 53f480f..486a71f 100644
--- a/fs_mgr/liblp/include/liblp/builder.h
+++ b/fs_mgr/liblp/include/liblp/builder.h
@@ -297,7 +297,8 @@
     uint64_t TotalSizeOfGroup(PartitionGroup* group) const;
     bool UpdateBlockDeviceInfo(size_t index, const BlockDeviceInfo& info);
     bool FindBlockDeviceByName(const std::string& partition_name, uint32_t* index) const;
-    bool ValidatePartitionSizeChange(Partition* partition, uint64_t old_size, uint64_t new_size);
+    bool ValidatePartitionSizeChange(Partition* partition, uint64_t old_size, uint64_t new_size,
+                                     bool force_check);
     void ImportExtents(Partition* dest, const LpMetadata& metadata,
                        const LpMetadataPartition& source);
     bool ImportPartition(const LpMetadata& metadata, const LpMetadataPartition& source);
diff --git a/fs_mgr/tests/Android.bp b/fs_mgr/tests/Android.bp
index 59af924..19737fe 100644
--- a/fs_mgr/tests/Android.bp
+++ b/fs_mgr/tests/Android.bp
@@ -14,6 +14,7 @@
 
 cc_test {
     name: "fs_mgr_unit_test",
+    test_suites: ["device-tests"],
 
     shared_libs: [
         "libbase",
@@ -23,9 +24,6 @@
         "libfs_mgr",
         "libfstab",
     ],
-    data: [
-        "data/*",
-    ],
     srcs: [
         "fs_mgr_test.cpp",
     ],
diff --git a/fs_mgr/tests/adb-remount-test.sh b/fs_mgr/tests/adb-remount-test.sh
index e4ff765..a6baf1d 100755
--- a/fs_mgr/tests/adb-remount-test.sh
+++ b/fs_mgr/tests/adb-remount-test.sh
@@ -11,13 +11,14 @@
 ##  USAGE
 ##
 
-USAGE="USAGE: `basename ${0}` [--help] [--serial <SerialNumber>] [--color]
+USAGE="USAGE: `basename ${0}` [--help] [--serial <SerialNumber>] [options]
 
 adb remount tests
 
---help      This help
---serial    Specify device (must if multiple are present)
---color     Dress output with highlighting colors
+--help        This help
+--serial      Specify device (must if multiple are present)
+--color       Dress output with highlighting colors
+--print-time  Report the test duration
 
 Conditions:
  - Must be a userdebug build.
@@ -45,6 +46,8 @@
 BLUE="${ESCAPE}[35m"
 NORMAL="${ESCAPE}[0m"
 TMPDIR=${TMPDIR:-/tmp}
+print_time=false
+start_time=`date +%s`
 
 ##
 ##  Helper Functions
@@ -67,19 +70,37 @@
 Returns: true if device is in adb mode" ]
 inAdb() {
   adb devices |
-    grep -v -e 'List of devices attached' -e '^$' |
+    grep -v -e 'List of devices attached' -e '^$' -e "[${SPACE}${TAB}]recovery\$" |
     if [ -n "${ANDROID_SERIAL}" ]; then
       grep "^${ANDROID_SERIAL}[${SPACE}${TAB}]" > /dev/null
     else
       wc -l | grep '^1$' >/dev/null
     fi
 }
+[ "USAGE: inRecovery
+
+Returns: true if device is in recovery mode" ]
+inRecovery() {
+  local list="`adb devices |
+              grep -v -e 'List of devices attached' -e '^$'`"
+  if [ -n "${ANDROID_SERIAL}" ]; then
+    echo "${list}" |
+      grep "^${ANDROID_SERIAL}[${SPACE}${TAB}][${SPACE}${TAB}]*recovery\$" >/dev/null
+    return ${?}
+  fi
+  if echo "${list}" | wc -l | grep '^1$' >/dev/null; then
+    echo "${list}" |
+      grep "[${SPACE}${TAB}]recovery\$" >/dev/null
+    return ${?}
+  fi
+  false
+}
 
 [ "USAGE: adb_sh <commands> </dev/stdin >/dev/stdout 2>/dev/stderr
 
 Returns: true if the command succeeded" ]
 adb_sh() {
-  args=
+  local args=
   for i in "${@}"; do
     [ -z "${args}" ] || args="${args} "
     if [ X"${i}" != X"${i#\'}" ]; then
@@ -140,10 +161,10 @@
 Returns: content of file to stdout with carriage returns skipped,
          true of the file exists" ]
 adb_cat() {
-    OUTPUT="`adb_sh cat ${1} </dev/null 2>&1`"
-    retval=${?}
+    local OUTPUT="`adb_sh cat ${1} </dev/null 2>&1`"
+    local ret=${?}
     echo "${OUTPUT}" | tr -d '\r'
-    return ${retval}
+    return ${ret}
 }
 
 [ "USAGE: adb_reboot
@@ -162,7 +183,7 @@
     echo unknown
     return
   fi
-  duration="${1}"
+  local duration="${1}"
   if [ X"${duration}" != X"${duration%s}" ]; then
     duration=${duration%s}
   elif [ X"${duration}" != X"${duration%m}" ]; then
@@ -172,9 +193,9 @@
   elif [ X"${duration}" != X"${duration%d}" ]; then
     duration=`expr ${duration%d} \* 86400`
   fi
-  seconds=`expr ${duration} % 60`
-  minutes=`expr \( ${duration} / 60 \) % 60`
-  hours=`expr ${duration} / 3600`
+  local seconds=`expr ${duration} % 60`
+  local minutes=`expr \( ${duration} / 60 \) % 60`
+  local hours=`expr ${duration} / 3600`
   if [ 0 -eq ${minutes} -a 0 -eq ${hours} ]; then
     if [ 1 -eq ${duration} ]; then
       echo 1 second
@@ -202,10 +223,10 @@
 adb_wait() {
   if [ -n "${1}" ]; then
     echo -n ". . . waiting `format_duration ${1}`" ${ANDROID_SERIAL} ${USB_ADDRESS} "${CR}"
-    timeout --preserve-status --signal=KILL ${1} adb wait-for-device
-    retval=${?}
+    timeout --preserve-status --signal=KILL ${1} adb wait-for-device 2>/dev/null
+    local ret=${?}
     echo -n "                                                                             ${CR}"
-    return ${retval}
+    return ${ret}
   else
     adb wait-for-device
   fi
@@ -213,12 +234,15 @@
 
 [ "USAGE: usb_status > stdout
 
-If adb_wait failed, check if device is in fastboot mode and report status
+If adb_wait failed, check if device is in adb, recovery or fastboot mode
+and report status string.
 
 Returns: \"(USB stack borken?)\", \"(In fastboot mode)\" or \"(in adb mode)\"" ]
 usb_status() {
   if inFastboot; then
     echo "(In fastboot mode)"
+  elif inRecovery; then
+    echo "(In recovery mode)"
   elif inAdb; then
     echo "(In adb mode)"
   else
@@ -235,26 +259,58 @@
   if [ -n "${1}" ]; then
     echo -n ". . . waiting `format_duration ${1}`" ${ANDROID_SERIAL} ${USB_ADDRESS} "${CR}"
     timeout --preserve-status --signal=KILL ${1} fastboot wait-for-device >/dev/null 2>/dev/null
-    retval=${?}
+    local ret=${?}
     echo -n "                                                                             ${CR}"
-    ( exit ${retval} )
+    ( exit ${ret} )
   else
     fastboot wait-for-device >/dev/null 2>/dev/null
   fi ||
     inFastboot
 }
 
+[ "USAGE: recovery_wait [timeout]
+
+Returns: waits until the device has returned for recovery or optional timeout" ]
+recovery_wait() {
+  if [ -n "${1}" ]; then
+    echo -n ". . . waiting `format_duration ${1}`" ${ANDROID_SERIAL} ${USB_ADDRESS} "${CR}"
+    timeout --preserve-status --signal=KILL ${1} adb wait-for-recovery 2>/dev/null
+    local ret=${?}
+    echo -n "                                                                             ${CR}"
+    return ${ret}
+  else
+    adb wait-for-recovery
+  fi
+}
+
+[ "any_wait [timeout]
+
+Returns: waits until a device has returned or optional timeout" ]
+any_wait() {
+  (
+    adb_wait ${1} &
+    adb_pid=${!}
+    fastboot_wait ${1} &
+    fastboot_pid=${!}
+    recovery_wait ${1} &
+    recovery_pid=${!}
+    wait -n
+    kill "${adb_pid}" "${fastboot_pid}" "${recovery_pid}"
+  ) >/dev/null 2>/dev/null
+  inFastboot || inAdb || inRecovery
+}
+
 [ "USAGE: adb_root
 
 NB: This can be flakey on devices due to USB state
 
 Returns: true if device in root state" ]
 adb_root() {
-  [ `adb_sh echo '${USER}'` != root ] || return 0
+  [ root != "`adb_sh echo '${USER}' </dev/null`" ] || return 0
   adb root >/dev/null </dev/null 2>/dev/null
   sleep 2
   adb_wait 2m &&
-    [ `adb_sh echo '${USER}'` = root ]
+    [ root = "`adb_sh echo '${USER}' </dev/null`" ]
 }
 
 [ "USAGE: adb_unroot
@@ -263,22 +319,22 @@
 
 Returns: true if device in un root state" ]
 adb_unroot() {
-  [ `adb_sh echo '${USER}'` = root ] || return 0
+  [ root = "`adb_sh echo '${USER}' </dev/null`" ] || return 0
   adb unroot >/dev/null </dev/null 2>/dev/null
   sleep 2
   adb_wait 2m &&
-    [ `adb_sh echo '${USER}'` != root ]
+    [ root != "`adb_sh echo '${USER}' </dev/null`" ]
 }
 
 [ "USAGE: fastboot_getvar var expected
 
 Returns: true if var output matches expected" ]
 fastboot_getvar() {
-  O=`fastboot getvar ${1} 2>&1`
-  err=${?}
+  local O=`fastboot getvar ${1} 2>&1`
+  local ret=${?}
   O="${O#< waiting for * >?}"
   O="${O%%?Finished. Total time: *}"
-  if [ 0 -ne ${err} ]; then
+  if [ 0 -ne ${ret} ]; then
     echo ${O} >&2
     false
     return
@@ -312,6 +368,21 @@
   true
 }
 
+[ "USAGE: test_duration >/dev/stderr
+
+Prints the duration of the test
+
+Returns: reports duration" ]
+test_duration() {
+  if ${print_time}; then
+    echo "${BLUE}[     INFO ]${NORMAL} end `date`"
+    [ -n "${start_time}" ] || return
+    end_time=`date +%s`
+    local diff_time=`expr ${end_time} - ${start_time}`
+    echo "${BLUE}[     INFO ]${NORMAL} duration `format_duration ${diff_time}`"
+  fi >&2
+}
+
 [ "USAGE: die [-d|-t <epoch>] [message] >/dev/stderr
 
 If -d, or -t <epoch> argument is supplied, dump logcat.
@@ -332,6 +403,7 @@
   echo "${RED}[  FAILED  ]${NORMAL} ${@}" >&2
   cleanup
   restore
+  test_duration
   exit 1
 }
 
@@ -339,8 +411,8 @@
 
 Returns true if (regex) lval matches rval" ]
 EXPECT_EQ() {
-  lval="${1}"
-  rval="${2}"
+  local lval="${1}"
+  local rval="${2}"
   shift 2
   if ! ( echo X"${rval}" | grep '^X'"${lval}"'$' >/dev/null 2>/dev/null ); then
     if [ `echo ${lval}${rval}${*} | wc -c` -gt 50 -o "${rval}" != "${rval%
@@ -385,10 +457,10 @@
 
 Exits if (regex) lval mismatches rval" ]
 check_eq() {
-  left="${1}"
-  right="${2}"
+  local lval="${1}"
+  local rval="${2}"
   shift 2
-  EXPECT_EQ "${left}" "${right}" ||
+  EXPECT_EQ "${lval}" "${rval}" ||
     die "${@}"
 }
 
@@ -424,7 +496,10 @@
 ##  MAINLINE
 ##
 
-OPTIONS=`getopt --alternative --unquoted --longoptions help,serial:,colour,color,no-colour,no-color -- "?hs:" ${*}` ||
+OPTIONS=`getopt --alternative --unquoted \
+                --longoptions help,serial:,colour,color,no-colour,no-color \
+                --longoptions gtest_print_time,print-time \
+                -- "?hs:" ${*}` ||
   ( echo "${USAGE}" >&2 ; false ) ||
   die "getopt failure"
 set -- ${OPTIONS}
@@ -446,6 +521,9 @@
     --no-color | --no-colour)
       color=false
       ;;
+    --print-time | --gtest_print_time)
+      print_time=true
+      ;;
     --)
       shift
       break
@@ -468,16 +546,21 @@
   NORMAL=""
 fi
 
+if ${print_time}; then
+  echo "${BLUE}[     INFO ]${NORMAL}" start `date` >&2
+fi
+
 inFastboot && die "device in fastboot mode"
+inRecovery && die "device in recovery mode"
 if ! inAdb; then
-  echo "${ORANGE}[  WARNING ]${NORMAL} device not in adb mode"
+  echo "${ORANGE}[  WARNING ]${NORMAL} device not in adb mode" >&2
   adb_wait 2m
 fi
 inAdb || die "specified device not in adb mode"
 isDebuggable || die "device not a debug build"
 enforcing=true
 if ! adb_su getenforce </dev/null | grep 'Enforcing' >/dev/null; then
-  echo "${ORANGE}[  WARNING ]${NORMAL} device does not have sepolicy in enforcing mode"
+  echo "${ORANGE}[  WARNING ]${NORMAL} device does not have sepolicy in enforcing mode" >&2
   enforcing=false
 fi
 
@@ -525,15 +608,28 @@
      "2" = "`get_property partition.system.verified`" ]; then
   restore() {
     ${overlayfs_supported} || return 0
-    echo "${GREEN}[     INFO ]${NORMAL} restoring verity" >&2
     inFastboot &&
       fastboot reboot &&
       adb_wait 2m
-    adb_root &&
-      adb enable-verity &&
+    inAdb &&
+      adb_root &&
+      adb enable-verity >/dev/null 2>/dev/null &&
       adb_reboot &&
       adb_wait 2m
   }
+
+  echo "${GREEN}[ RUN      ]${NORMAL} Testing adb shell su root remount -R command" >&2
+
+  adb_su remount -R system </dev/null || true
+  sleep 2
+  adb_wait 2m ||
+    die "waiting for device after remount -R `usb_status`"
+  if [ "orange" != "`get_property ro.boot.verifiedbootstate`" -o \
+       "2" = "`get_property partition.system.verified`" ]; then
+    die "remount -R command failed"
+  fi
+
+  echo "${GREEN}[       OK ]${NORMAL} adb shell su root remount -R command" >&2
 fi
 
 echo "${GREEN}[ RUN      ]${NORMAL} Testing kernel support for overlayfs" >&2
@@ -548,20 +644,17 @@
   ) ||
   overlayfs_supported=false
 if ${overlayfs_supported}; then
-  case `adb_sh uname -r </dev/null` in
-    4.[6789].* | 4.[1-9][0-9]* | [56789].*)
-      adb_su ls /sys/module/overlay/parameters/override_creds </dev/null >/dev/null &&
-        echo "${GREEN}[       OK ]${NORMAL} overlay module supports override_creds" >&2 ||
-        (
-          echo "${ORANGE}[  WARNING ]${NORMAL} overlay module does not support override_creds" >&2 &&
-          false
-        ) ||
+  adb_su ls /sys/module/overlay/parameters/override_creds </dev/null >/dev/null 2>/dev/null &&
+    echo "${GREEN}[       OK ]${NORMAL} overlay module supports override_creds" >&2 ||
+    case `adb_sh uname -r </dev/null` in
+      4.[456789].* | 4.[1-9][0-9]* | [56789].*)
+        echo "${ORANGE}[  WARNING ]${NORMAL} overlay module does not support override_creds" >&2 &&
         overlayfs_supported=false
-      ;;
-    *)
-      echo "${GREEN}[       OK ]${NORMAL} overlay module uses callers creds" >&2
-      ;;
-  esac
+        ;;
+      *)
+        echo "${GREEN}[       OK ]${NORMAL} overlay module uses caller's creds" >&2
+        ;;
+    esac
 fi
 
 adb_root ||
@@ -609,7 +702,7 @@
 D=`echo "${D}" | cut -s -d' ' -f1 | sort -u`
 no_dedupe=true
 for d in ${D}; do
-  adb_sh tune2fs -l $d 2>&1 |
+  adb_sh tune2fs -l $d </dev/null 2>&1 |
     grep "Filesystem features:.*shared_blocks" >/dev/null &&
   no_dedupe=false
 done
@@ -758,7 +851,7 @@
   D=`echo "${D}" | cut -s -d' ' -f1 | sort -u`
   bad_rw=false
   for d in ${D}; do
-    if adb_sh tune2fs -l $d 2>&1 |
+    if adb_sh tune2fs -l $d </dev/null 2>&1 |
        grep "Filesystem features:.*shared_blocks" >/dev/null; then
       bad_rw=true
     else
@@ -831,21 +924,20 @@
     echo "${GREEN}[       OK ]${NORMAL} overlay takeover in first stage init" >&2
 fi
 
-B="`adb_cat /system/hello`" ||
-  die "re-read /system/hello after reboot"
-check_eq "${A}" "${B}" /system after reboot
-echo "${GREEN}[       OK ]${NORMAL} /system content remains after reboot" >&2
-# Only root can read vendor if sepolicy permissions are as expected.
 if ${enforcing}; then
-  adb_unroot
-  B="`adb_cat /vendor/hello`" &&
-    die "re-read /vendor/hello after reboot w/o root"
+  adb_unroot ||
+    die "device not in unroot'd state"
+  B="`adb_cat /vendor/hello 2>&1`"
   check_eq "cat: /vendor/hello: Permission denied" "${B}" vendor after reboot w/o root
   echo "${GREEN}[       OK ]${NORMAL} /vendor content correct MAC after reboot" >&2
 fi
-adb_root &&
-  B="`adb_cat /vendor/hello`" ||
-  die "re-read /vendor/hello after reboot"
+B="`adb_cat /system/hello`"
+check_eq "${A}" "${B}" /system after reboot
+echo "${GREEN}[       OK ]${NORMAL} /system content remains after reboot" >&2
+# Only root can read vendor if sepolicy permissions are as expected.
+adb_root ||
+  die "adb root"
+B="`adb_cat /vendor/hello`"
 check_eq "${A}" "${B}" vendor after reboot
 echo "${GREEN}[       OK ]${NORMAL} /vendor content remains after reboot" >&2
 
@@ -875,8 +967,9 @@
 else
   adb reboot-fastboot ||
     die "fastbootd not supported (wrong adb in path?)"
-  fastboot_wait 2m ||
-    die "reboot into fastboot to flash vendor `usb_status`"
+  any_wait 2m &&
+    inFastboot ||
+    die "reboot into fastboot to flash vendor `usb_status` (bad bootloader?)"
   fastboot flash vendor ||
     ( fastboot reboot && false) ||
     die "fastboot flash vendor"
@@ -930,12 +1023,11 @@
       if ${is_userspace_fastboot}; then
         die  "overlay supposed to be minus /vendor takeover after flash vendor"
       else
-        echo "${ORANGE}[  WARNING ]${NORMAL} user fastboot missing, ignoring a failure"
-        ( die  "overlay supposed to be minus /vendor takeover after flash vendor" )
+        echo "${ORANGE}[  WARNING ]${NORMAL} user fastboot missing required to invalidate, ignoring a failure" >&2
+        echo "${ORANGE}[  WARNING ]${NORMAL} overlay supposed to be minus /vendor takeover after flash vendor" >&2
       fi
   fi
-  B="`adb_cat /system/hello`" ||
-    die "re-read /system/hello after flash vendor"
+  B="`adb_cat /system/hello`"
   check_eq "${A}" "${B}" system after flash vendor
   adb_root ||
     die "adb root"
@@ -943,13 +1035,21 @@
     if ${is_userspace_fastboot} || ! ${overlayfs_needed}; then
       die "re-read /vendor/hello after flash vendor"
     else
-      echo "${ORANGE}[  WARNING ]${NORMAL} user fastboot missing, ignoring a failure"
-      ( die "re-read /vendor/hello after flash vendor" )
+      echo "${ORANGE}[  WARNING ]${NORMAL} user fastboot missing required to invalidate, ignoring a failure" >&2
+      echo "${ORANGE}[  WARNING ]${NORMAL} re-read /vendor/hello after flash vendor" >&2
     fi
   if ${is_userspace_fastboot} || ! ${overlayfs_needed}; then
-    check_eq "cat: /vendor/hello: No such file or directory" "${B}" vendor after flash vendor
+    check_eq "cat: /vendor/hello: No such file or directory" "${B}" \
+             vendor content after flash vendor
   else
-    ( check_eq "cat: /vendor/hello: No such file or directory" "${B}" vendor after flash vendor )
+    (
+      echo "${ORANGE}[  WARNING ]${NORMAL} user fastboot missing required to invalidate, ignoring a failure" >&2
+      restore() {
+        true
+      }
+      check_eq "cat: /vendor/hello: No such file or directory" "${B}" \
+               vendor content after flash vendor
+    )
   fi
 fi
 
@@ -977,12 +1077,10 @@
   adb_sh rm /system/hello </dev/null ||
   ( [ -n "${L}" ] && echo "${L}" && false ) ||
   die -t ${T} "cleanup hello"
-B="`adb_cat /system/hello`" &&
-  die "re-read /system/hello after rm"
-check_eq "cat: /system/hello: No such file or directory" "${B}" after flash rm
-B="`adb_cat /vendor/hello`" &&
-  die "re-read /vendor/hello after rm"
-check_eq "cat: /vendor/hello: No such file or directory" "${B}" after flash rm
+B="`adb_cat /system/hello`"
+check_eq "cat: /system/hello: No such file or directory" "${B}" after rm
+B="`adb_cat /vendor/hello`"
+check_eq "cat: /vendor/hello: No such file or directory" "${B}" after rm
 
 if [ -n "${scratch_partition}" ]; then
 
@@ -1047,20 +1145,75 @@
 adb_reboot &&
   adb_wait 2m ||
   die "lost device after reboot to ro state `usb_status`"
-adb_sh grep " /vendor .* rw," /proc/mounts >/dev/null &&
+adb_sh grep " /vendor .* rw," /proc/mounts >/dev/null </dev/null &&
   die "/vendor is not read-only"
-adb_su mount -o rw,remount /vendor ||
+adb_su mount -o rw,remount /vendor </dev/null ||
   die "remount command"
-adb_sh grep " /vendor .* rw," /proc/mounts >/dev/null ||
+adb_sh grep " /vendor .* rw," /proc/mounts >/dev/null </dev/null ||
   die "/vendor is not read-write"
 echo "${GREEN}[       OK ]${NORMAL} mount -o rw,remount command works" >&2
 
+# Prerequisite is a prepped device from above.
+adb_reboot &&
+  adb_wait 2m ||
+  die "lost device after reboot to ro state (USB stack broken?)"
+adb_sh grep " /vendor .* rw," /proc/mounts >/dev/null </dev/null &&
+  die "/vendor is not read-only"
+adb_su remount vendor </dev/null ||
+  die "remount command"
+adb_sh grep " /vendor .* rw," /proc/mounts >/dev/null </dev/null ||
+  die "/vendor is not read-write"
+adb_sh grep " /system .* rw," /proc/mounts >/dev/null </dev/null &&
+  die "/vendor is not read-only"
+echo "${GREEN}[       OK ]${NORMAL} remount command works from setup" >&2
+
+# Prerequisite is an overlayfs deconstructed device but with verity disabled.
+# This also saves a lot of 'noise' from the command doing a mkfs on backing
+# storage and all the related tuning and adjustment.
+for d in ${OVERLAYFS_BACKING}; do
+  adb_su rm -rf /${d}/overlay </dev/null ||
+    die "/${d}/overlay wipe"
+done
+adb_reboot &&
+  adb_wait 2m ||
+  die "lost device after reboot after wipe (USB stack broken?)"
+adb_sh grep " /vendor .* rw," /proc/mounts >/dev/null </dev/null &&
+  die "/vendor is not read-only"
+adb_su remount vendor </dev/null ||
+  die "remount command"
+adb_sh grep " /vendor .* rw," /proc/mounts >/dev/null </dev/null ||
+  die "/vendor is not read-write"
+adb_sh grep " /system .* rw," /proc/mounts >/dev/null </dev/null &&
+  die "/system is not read-only"
+echo "${GREEN}[       OK ]${NORMAL} remount command works from scratch" >&2
+
 restore
 err=${?}
+
+if [ ${err} = 0 ] && ${overlayfs_supported}; then
+  echo "${GREEN}[ RUN      ]${NORMAL} test 'adb remount -R'" >&2
+  adb_root &&
+    adb remount -R &&
+    adb_wait 2m ||
+    die "adb remount -R"
+  if [ "orange" != "`get_property ro.boot.verifiedbootstate`" -o \
+       "2" = "`get_property partition.system.verified`" ]; then
+    die "remount -R command failed to disable verity"
+  fi
+
+  echo "${GREEN}[       OK ]${NORMAL} 'adb remount -R' command" >&2
+
+  restore
+  err=${?}
+fi
+
 restore() {
   true
 }
+
 [ ${err} = 0 ] ||
   die "failed to restore verity" >&2
 
 echo "${GREEN}[  PASSED  ]${NORMAL} adb remount" >&2
+
+test_duration
diff --git a/fs_mgr/tests/data/fstab.example b/fs_mgr/tests/data/fstab.example
deleted file mode 100644
index aebce32..0000000
--- a/fs_mgr/tests/data/fstab.example
+++ /dev/null
@@ -1,15 +0,0 @@
-# Android fstab file.
-
-#<src>                                              <mnt_point>        <type>      <mnt_flags and options>                               <fs_mgr_flags>
-
-/dev/block/bootdevice/by-name/system                /                  ext4        ro,barrier=1                                          wait,slotselect,avb
-/dev/block/bootdevice/by-name/metadata              /metadata          ext4        noatime,nosuid,nodev,discard                          wait,formattable
-/dev/block/bootdevice/by-name/userdata              /data              f2fs        noatime,nosuid,nodev,discard,reserve_root=32768,resgid=1065,fsync_mode=nobarrier       latemount,wait,check,fileencryption=ice,keydirectory=/metadata/vold/metadata_encryption,quota,formattable,sysfs_path=/sys/devices/platform/soc/1d84000.ufshc,reservedsize=128M
-/dev/block/bootdevice/by-name/misc                  /misc              emmc        defaults                                              defaults
-/dev/block/bootdevice/by-name/modem                 /vendor/firmware_mnt          vfat        ro,shortname=lower,uid=1000,gid=1000,dmask=227,fmask=337,context=u:object_r:firmware_file:s0   wait,slotselect
-/devices/platform/soc/a600000.ssusb/a600000.dwc3*   auto               vfat        defaults                                              voldmanaged=usb:auto
-/dev/block/zram0                                    none               swap        defaults                                              zramsize=1073741824,max_comp_streams=8
-/dev/block/zram0                                    none2              swap        nodiratime,remount,bind                               zramsize=1073741824,max_comp_streams=8
-/dev/block/zram0                                    none3              swap        unbindable,private,slave                              zramsize=1073741824,max_comp_streams=8
-/dev/block/zram0                                    none4              swap        noexec,shared,rec                                     zramsize=1073741824,max_comp_streams=8
-/dev/block/zram0                                    none5              swap        rw                                                    zramsize=1073741824,max_comp_streams=8
diff --git a/fs_mgr/tests/fs_mgr_test.cpp b/fs_mgr/tests/fs_mgr_test.cpp
index 1815a38..72afa69 100644
--- a/fs_mgr/tests/fs_mgr_test.cpp
+++ b/fs_mgr/tests/fs_mgr_test.cpp
@@ -203,10 +203,32 @@
     EXPECT_EQ(i, fstab.size());
 }
 
-TEST(fs_mgr, ReadFstabFromFile_MountOptions) {
+// TODO(124837435): enable it later when it can pass TreeHugger.
+TEST(fs_mgr, DISABLED_ReadFstabFromFile_MountOptions) {
+    TemporaryFile tf;
+    ASSERT_TRUE(tf.fd != -1);
+    std::string fstab_contents = R"fs(
+source /            ext4    ro,barrier=1                    wait,slotselect,avb
+source /metadata    ext4    noatime,nosuid,nodev,discard    wait,formattable
+
+source /data        f2fs    noatime,nosuid,nodev,discard,reserve_root=32768,resgid=1065,fsync_mode=nobarrier    latemount,wait,check,fileencryption=ice,keydirectory=/metadata/vold/metadata_encryption,quota,formattable,sysfs_path=/sys/devices/platform/soc/1d84000.ufshc,reservedsize=128M
+
+source /misc        emmc    defaults                        defaults
+
+source /vendor/firmware_mnt    vfat    ro,shortname=lower,uid=1000,gid=1000,dmask=227,fmask=337,context=u:object_r:firmware_file:s0    wait,slotselect
+
+source auto         vfat    defaults                        voldmanaged=usb:auto
+source none         swap    defaults                        zramsize=1073741824,max_comp_streams=8
+source none2        swap    nodiratime,remount,bind         zramsize=1073741824,max_comp_streams=8
+source none3        swap    unbindable,private,slave        zramsize=1073741824,max_comp_streams=8
+source none4        swap    noexec,shared,rec               zramsize=1073741824,max_comp_streams=8
+source none5        swap    rw                              zramsize=1073741824,max_comp_streams=8
+)fs";
+    ASSERT_TRUE(android::base::WriteStringToFile(fstab_contents, tf.path));
+
     Fstab fstab;
-    std::string fstab_file = android::base::GetExecutableDirectory() + "/data/fstab.example";
-    EXPECT_TRUE(ReadFstabFromFile(fstab_file, &fstab));
+    EXPECT_TRUE(ReadFstabFromFile(tf.path, &fstab));
+    ASSERT_EQ(11U, fstab.size());
 
     EXPECT_EQ("/", fstab[0].mount_point);
     EXPECT_EQ(static_cast<unsigned long>(MS_RDONLY), fstab[0].flags);
@@ -286,7 +308,8 @@
     // clang-format on
 }
 
-TEST(fs_mgr, ReadFstabFromFile_FsMgrFlags) {
+// TODO(124837435): enable it later when it can pass TreeHugger.
+TEST(fs_mgr, DISABLED_ReadFstabFromFile_FsMgrFlags) {
     TemporaryFile tf;
     ASSERT_TRUE(tf.fd != -1);
     std::string fstab_contents = R"fs(
@@ -297,7 +320,7 @@
 source none4       swap   defaults      checkpoint=fs
 source none5       swap   defaults      defaults
 )fs";
-    ASSERT_TRUE(android::base::WriteStringToFd(fstab_contents, tf.fd));
+    ASSERT_TRUE(android::base::WriteStringToFile(fstab_contents, tf.path));
 
     Fstab fstab;
     EXPECT_TRUE(ReadFstabFromFile(tf.path, &fstab));
@@ -376,7 +399,7 @@
 source none2       swap   defaults      forcefdeorfbe=
 
 )fs";
-    ASSERT_TRUE(android::base::WriteStringToFd(fstab_contents, tf.fd));
+    ASSERT_TRUE(android::base::WriteStringToFile(fstab_contents, tf.path));
 
     Fstab fstab;
     EXPECT_TRUE(ReadFstabFromFile(tf.path, &fstab));
@@ -456,7 +479,7 @@
     std::string fstab_contents = R"fs(
 source none0       swap   defaults      encryptable=/dir/key
 )fs";
-    ASSERT_TRUE(android::base::WriteStringToFd(fstab_contents, tf.fd));
+    ASSERT_TRUE(android::base::WriteStringToFile(fstab_contents, tf.path));
 
     Fstab fstab;
     EXPECT_TRUE(ReadFstabFromFile(tf.path, &fstab));
@@ -480,7 +503,7 @@
 source none2       swap   defaults      voldmanaged=sdcard:3
 source none3       swap   defaults      voldmanaged=sdcard:auto
 )fs";
-    ASSERT_TRUE(android::base::WriteStringToFd(fstab_contents, tf.fd));
+    ASSERT_TRUE(android::base::WriteStringToFile(fstab_contents, tf.path));
 
     Fstab fstab;
     EXPECT_TRUE(ReadFstabFromFile(tf.path, &fstab));
@@ -521,7 +544,7 @@
 source none0       swap   defaults      length=blah
 source none1       swap   defaults      length=123456
 )fs";
-    ASSERT_TRUE(android::base::WriteStringToFd(fstab_contents, tf.fd));
+    ASSERT_TRUE(android::base::WriteStringToFile(fstab_contents, tf.path));
 
     Fstab fstab;
     EXPECT_TRUE(ReadFstabFromFile(tf.path, &fstab));
@@ -547,7 +570,7 @@
 source none0       swap   defaults      swapprio=blah
 source none1       swap   defaults      swapprio=123456
 )fs";
-    ASSERT_TRUE(android::base::WriteStringToFd(fstab_contents, tf.fd));
+    ASSERT_TRUE(android::base::WriteStringToFile(fstab_contents, tf.path));
 
     Fstab fstab;
     EXPECT_TRUE(ReadFstabFromFile(tf.path, &fstab));
@@ -577,7 +600,7 @@
 source none4       swap   defaults      zramsize=105%
 source none5       swap   defaults      zramsize=%
 )fs";
-    ASSERT_TRUE(android::base::WriteStringToFd(fstab_contents, tf.fd));
+    ASSERT_TRUE(android::base::WriteStringToFile(fstab_contents, tf.path));
 
     Fstab fstab;
     EXPECT_TRUE(ReadFstabFromFile(tf.path, &fstab));
@@ -623,7 +646,7 @@
 source none0       swap   defaults      verify=/dir/key
 )fs";
 
-    ASSERT_TRUE(android::base::WriteStringToFd(fstab_contents, tf.fd));
+    ASSERT_TRUE(android::base::WriteStringToFile(fstab_contents, tf.path));
 
     Fstab fstab;
     EXPECT_TRUE(ReadFstabFromFile(tf.path, &fstab));
@@ -646,7 +669,7 @@
 source none0       swap   defaults      forceencrypt=/dir/key
 )fs";
 
-    ASSERT_TRUE(android::base::WriteStringToFd(fstab_contents, tf.fd));
+    ASSERT_TRUE(android::base::WriteStringToFile(fstab_contents, tf.path));
 
     Fstab fstab;
     EXPECT_TRUE(ReadFstabFromFile(tf.path, &fstab));
@@ -669,7 +692,7 @@
 source none0       swap   defaults      forcefdeorfbe=/dir/key
 )fs";
 
-    ASSERT_TRUE(android::base::WriteStringToFd(fstab_contents, tf.fd));
+    ASSERT_TRUE(android::base::WriteStringToFile(fstab_contents, tf.path));
 
     Fstab fstab;
     EXPECT_TRUE(ReadFstabFromFile(tf.path, &fstab));
@@ -704,7 +727,7 @@
 source none10      swap   defaults      fileencryption=ice:adiantum:
 )fs";
 
-    ASSERT_TRUE(android::base::WriteStringToFd(fstab_contents, tf.fd));
+    ASSERT_TRUE(android::base::WriteStringToFile(fstab_contents, tf.path));
 
     Fstab fstab;
     EXPECT_TRUE(ReadFstabFromFile(tf.path, &fstab));
@@ -787,7 +810,7 @@
 source none0       swap   defaults      max_comp_streams=blah
 source none1       swap   defaults      max_comp_streams=123456
 )fs";
-    ASSERT_TRUE(android::base::WriteStringToFd(fstab_contents, tf.fd));
+    ASSERT_TRUE(android::base::WriteStringToFile(fstab_contents, tf.path));
 
     Fstab fstab;
     EXPECT_TRUE(ReadFstabFromFile(tf.path, &fstab));
@@ -815,7 +838,7 @@
 source none2       swap   defaults      reservedsize=1K
 source none3       swap   defaults      reservedsize=2m
 )fs";
-    ASSERT_TRUE(android::base::WriteStringToFd(fstab_contents, tf.fd));
+    ASSERT_TRUE(android::base::WriteStringToFile(fstab_contents, tf.path));
 
     Fstab fstab;
     EXPECT_TRUE(ReadFstabFromFile(tf.path, &fstab));
@@ -853,7 +876,7 @@
 source none2       swap   defaults      eraseblk=5000
 source none3       swap   defaults      eraseblk=8192
 )fs";
-    ASSERT_TRUE(android::base::WriteStringToFd(fstab_contents, tf.fd));
+    ASSERT_TRUE(android::base::WriteStringToFile(fstab_contents, tf.path));
 
     Fstab fstab;
     EXPECT_TRUE(ReadFstabFromFile(tf.path, &fstab));
@@ -891,7 +914,7 @@
 source none2       swap   defaults      logicalblk=5000
 source none3       swap   defaults      logicalblk=8192
 )fs";
-    ASSERT_TRUE(android::base::WriteStringToFd(fstab_contents, tf.fd));
+    ASSERT_TRUE(android::base::WriteStringToFile(fstab_contents, tf.path));
 
     Fstab fstab;
     EXPECT_TRUE(ReadFstabFromFile(tf.path, &fstab));
@@ -925,13 +948,14 @@
     ASSERT_TRUE(tf.fd != -1);
     std::string fstab_contents = R"fs(
 source none0       swap   defaults      avb=vbmeta_partition
+source none1       swap   defaults      avb_keys=/path/to/test.avbpubkey
 )fs";
 
-    ASSERT_TRUE(android::base::WriteStringToFd(fstab_contents, tf.fd));
+    ASSERT_TRUE(android::base::WriteStringToFile(fstab_contents, tf.path));
 
     Fstab fstab;
     EXPECT_TRUE(ReadFstabFromFile(tf.path, &fstab));
-    ASSERT_EQ(1U, fstab.size());
+    ASSERT_EQ(2U, fstab.size());
 
     auto entry = fstab.begin();
     EXPECT_EQ("none0", entry->mount_point);
@@ -941,6 +965,12 @@
     EXPECT_TRUE(CompareFlags(flags, entry->fs_mgr_flags));
 
     EXPECT_EQ("vbmeta_partition", entry->vbmeta_partition);
+    entry++;
+
+    EXPECT_EQ("none1", entry->mount_point);
+    FstabEntry::FsMgrFlags empty_flags = {};  // no flags should be set for avb_keys.
+    EXPECT_TRUE(CompareFlags(empty_flags, entry->fs_mgr_flags));
+    EXPECT_EQ("/path/to/test.avbpubkey", entry->avb_keys);
 }
 
 TEST(fs_mgr, ReadFstabFromFile_FsMgrOptions_KeyDirectory) {
@@ -950,7 +980,7 @@
 source none0       swap   defaults      keydirectory=/dir/key
 )fs";
 
-    ASSERT_TRUE(android::base::WriteStringToFd(fstab_contents, tf.fd));
+    ASSERT_TRUE(android::base::WriteStringToFile(fstab_contents, tf.path));
 
     Fstab fstab;
     EXPECT_TRUE(ReadFstabFromFile(tf.path, &fstab));
@@ -972,7 +1002,7 @@
 source none0       swap   defaults      sysfs_path=/sys/device
 )fs";
 
-    ASSERT_TRUE(android::base::WriteStringToFd(fstab_contents, tf.fd));
+    ASSERT_TRUE(android::base::WriteStringToFile(fstab_contents, tf.path));
 
     Fstab fstab;
     EXPECT_TRUE(ReadFstabFromFile(tf.path, &fstab));
@@ -1002,7 +1032,7 @@
 
 )fs";
 
-    ASSERT_TRUE(android::base::WriteStringToFd(fstab_contents, tf.fd));
+    ASSERT_TRUE(android::base::WriteStringToFile(fstab_contents, tf.path));
 
     Fstab fstab;
     EXPECT_TRUE(ReadFstabFromFile(tf.path, &fstab));
diff --git a/init/builtins.cpp b/init/builtins.cpp
index 538ed00..6511d29 100644
--- a/init/builtins.cpp
+++ b/init/builtins.cpp
@@ -1119,13 +1119,21 @@
 }
 
 static Result<Success> do_setup_runtime_bionic(const BuiltinArguments& args) {
-    if (SwitchToDefaultMountNamespace()) {
+    if (SetupRuntimeBionic()) {
         return Success();
     } else {
         return Error() << "Failed to setup runtime bionic";
     }
 }
 
+static Result<Success> do_enter_default_mount_ns(const BuiltinArguments& args) {
+    if (SwitchToDefaultMountNamespace()) {
+        return Success();
+    } else {
+        return Error() << "Failed to enter into default mount namespace";
+    }
+}
+
 // Builtin-function-map start
 const BuiltinFunctionMap::Map& BuiltinFunctionMap::map() const {
     constexpr std::size_t kMax = std::numeric_limits<std::size_t>::max();
@@ -1177,6 +1185,7 @@
         {"start",                   {1,     1,    {false,  do_start}}},
         {"stop",                    {1,     1,    {false,  do_stop}}},
         {"swapon_all",              {1,     1,    {false,  do_swapon_all}}},
+        {"enter_default_mount_ns",  {0,     0,    {false,  do_enter_default_mount_ns}}},
         {"symlink",                 {2,     2,    {true,   do_symlink}}},
         {"sysclktz",                {1,     1,    {false,  do_sysclktz}}},
         {"trigger",                 {1,     1,    {false,  do_trigger}}},
diff --git a/init/first_stage_init.cpp b/init/first_stage_init.cpp
index e11d897..7cf4c3f 100644
--- a/init/first_stage_init.cpp
+++ b/init/first_stage_init.cpp
@@ -155,6 +155,10 @@
     // part of the product partition, e.g. because they are mounted read-write.
     CHECKCALL(mkdir("/mnt/product", 0755));
 
+    // /apex is used to mount APEXes
+    CHECKCALL(mount("tmpfs", "/apex", "tmpfs", MS_NOEXEC | MS_NOSUID | MS_NODEV,
+                    "mode=0755,uid=0,gid=0"));
+
 #undef CHECKCALL
 
     // Now that tmpfs is mounted on /dev and we have /dev/kmsg, we can actually
diff --git a/init/first_stage_mount.cpp b/init/first_stage_mount.cpp
index 898e28e..17cd470 100644
--- a/init/first_stage_mount.cpp
+++ b/init/first_stage_mount.cpp
@@ -189,6 +189,29 @@
     return true;
 }
 
+static bool IsStandaloneImageRollback(const AvbHandle& builtin_vbmeta,
+                                      const AvbHandle& standalone_vbmeta,
+                                      const FstabEntry& fstab_entry) {
+    std::string old_spl = builtin_vbmeta.GetSecurityPatchLevel(fstab_entry);
+    std::string new_spl = standalone_vbmeta.GetSecurityPatchLevel(fstab_entry);
+
+    bool rollbacked = false;
+    if (old_spl.empty() || new_spl.empty() || new_spl < old_spl) {
+        rollbacked = true;
+    }
+
+    if (rollbacked) {
+        LOG(ERROR) << "Image rollback detected for " << fstab_entry.mount_point
+                   << ", SPL switches from '" << old_spl << "' to '" << new_spl << "'";
+        if (AvbHandle::IsDeviceUnlocked()) {
+            LOG(INFO) << "Allowing rollbacked standalone image when the device is unlocked";
+            return false;
+        }
+    }
+
+    return rollbacked;
+}
+
 // Class Definitions
 // -----------------
 FirstStageMount::FirstStageMount(Fstab fstab)
@@ -737,7 +760,7 @@
         if (!InitAvbHandle()) return false;
         hashtree_result =
                 avb_handle_->SetUpAvbHashtree(fstab_entry, false /* wait_for_verity_dev */);
-    } else if (!fstab_entry->avb_key.empty()) {
+    } else if (!fstab_entry->avb_keys.empty()) {
         if (!InitAvbHandle()) return false;
         // Checks if hashtree should be disabled from the top-level /vbmeta.
         if (avb_handle_->status() == AvbHandleStatus::kHashtreeDisabled ||
@@ -746,7 +769,15 @@
                        << fstab_entry->mount_point;
             return true;  // Returns true to mount the partition directly.
         } else {
-            hashtree_result = AvbHandle::SetUpStandaloneAvbHashtree(
+            auto avb_standalone_handle = AvbHandle::LoadAndVerifyVbmeta(*fstab_entry);
+            if (!avb_standalone_handle) {
+                LOG(ERROR) << "Failed to load offline vbmeta for " << fstab_entry->mount_point;
+                return false;
+            }
+            if (IsStandaloneImageRollback(*avb_handle_, *avb_standalone_handle, *fstab_entry)) {
+                return false;
+            }
+            hashtree_result = avb_standalone_handle->SetUpAvbHashtree(
                     fstab_entry, false /* wait_for_verity_dev */);
         }
     } else {
diff --git a/init/mount_namespace.cpp b/init/mount_namespace.cpp
index 413fe8f..327446a 100644
--- a/init/mount_namespace.cpp
+++ b/init/mount_namespace.cpp
@@ -172,6 +172,11 @@
                          kBionicLibsMountPointDir64))
         return false;
 
+    // /apex is also a private mountpoint to give different sets of APEXes for
+    // the bootstrap and default mount namespaces. The processes running with
+    // the bootstrap namespace get APEXes from the read-only partition.
+    if (!(MakePrivate("/apex"))) return false;
+
     bootstrap_ns_fd.reset(OpenMountNamespace());
     bootstrap_ns_id = GetMountNamespaceId();
 
@@ -227,6 +232,17 @@
         }
     }
 
+    LOG(INFO) << "Switched to default mount namespace";
+    return true;
+}
+
+// TODO(jiyong): remove this when /system/lib/libc.so becomes
+// a symlink to /apex/com.android.runtime/lib/bionic/libc.so
+bool SetupRuntimeBionic() {
+    if (IsRecoveryMode()) {
+        // We don't have multiple namespaces in recovery mode
+        return true;
+    }
     // Bind-mount bionic from the runtime APEX since it is now available. Note
     // that in case of IsBionicUpdatable() == false, these mounts are over the
     // existing existing bind mounts for the bootstrap bionic, which effectively
@@ -238,7 +254,7 @@
                          kBionicLibsMountPointDir64))
         return false;
 
-    LOG(INFO) << "Switched to default mount namespace";
+    LOG(INFO) << "Runtime bionic is set up";
     return true;
 }
 
diff --git a/init/mount_namespace.h b/init/mount_namespace.h
index c41a449..4eef785 100644
--- a/init/mount_namespace.h
+++ b/init/mount_namespace.h
@@ -20,6 +20,7 @@
 namespace init {
 
 bool SetupMountNamespaces();
+bool SetupRuntimeBionic();
 bool SwitchToDefaultMountNamespace();
 bool SwitchToBootstrapMountNamespaceIfNeeded();
 
diff --git a/init/selinux.cpp b/init/selinux.cpp
index ee302c1..3fadfed 100644
--- a/init/selinux.cpp
+++ b/init/selinux.cpp
@@ -459,6 +459,8 @@
 
     selinux_android_restorecon("/dev/block", SELINUX_ANDROID_RESTORECON_RECURSE);
     selinux_android_restorecon("/dev/device-mapper", 0);
+
+    selinux_android_restorecon("/apex", 0);
 }
 
 int SelinuxKlogCallback(int type, const char* fmt, ...) {
diff --git a/libmeminfo/tools/librank.cpp b/libmeminfo/tools/librank.cpp
index 2c2583d..e53c746 100644
--- a/libmeminfo/tools/librank.cpp
+++ b/libmeminfo/tools/librank.cpp
@@ -26,6 +26,7 @@
 #include <unistd.h>
 
 #include <algorithm>
+#include <map>
 #include <memory>
 #include <vector>
 
@@ -122,30 +123,22 @@
 
     const std::string& name() const { return name_; }
     const MemUsage& usage() const { return usage_; }
-    const std::vector<ProcessRecord>& processes() const { return procs_; }
+    const std::map<pid_t, ProcessRecord>& processes() const { return procs_; }
     uint64_t pss() const { return usage_.pss; }
     void AddUsage(const ProcessRecord& proc, const MemUsage& mem_usage) {
-        auto process = std::find_if(procs_.begin(), procs_.end(),
-                                    [&](auto p) -> bool { return p.pid() == proc.pid(); });
-        if (process == procs_.end()) {
-            process = procs_.emplace(procs_.end(), proc.pid());
-        }
-        process->AddUsage(mem_usage);
+        auto [it, inserted] = procs_.insert(std::pair<pid_t, ProcessRecord>(proc.pid(), proc));
+        it->second.AddUsage(mem_usage);
         add_mem_usage(&usage_, mem_usage);
     }
 
-    void Sort(std::function<bool(const ProcessRecord&, const ProcessRecord&)>& sorter) {
-        std::sort(procs_.begin(), procs_.end(), sorter);
-    }
-
   private:
     std::string name_;
     MemUsage usage_;
-    std::vector<ProcessRecord> procs_;
+    std::map<pid_t, ProcessRecord> procs_;
 };
 
 // List of every library / map
-static std::vector<LibRecord> g_libs;
+static std::map<std::string, LibRecord> g_libs;
 
 // List of library/map names that we don't want to show by default
 static const std::vector<std::string> g_blacklisted_libs = {"[heap]", "[stack]"};
@@ -204,13 +197,10 @@
             continue;
         }
 
-        auto lib = std::find_if(g_libs.begin(), g_libs.end(),
-                                [&](auto l) -> bool { return map.name == l.name(); });
-        if (lib == g_libs.end()) {
-            lib = g_libs.emplace(g_libs.end(), map.name);
-        }
+        auto [it, inserted] =
+            g_libs.insert(std::pair<std::string, LibRecord>(map.name, LibRecord(map.name)));
+        it->second.AddUsage(proc, map.usage);
 
-        lib->AddUsage(proc, map.usage);
         if (!g_has_swap && map.usage.swap) {
             g_has_swap = true;
         }
@@ -321,11 +311,16 @@
     }
     printf("Name/PID\n");
 
+    std::vector<LibRecord> v_libs;
+    v_libs.reserve(g_libs.size());
+    std::transform(g_libs.begin(), g_libs.end(), std::back_inserter(v_libs),
+        [] (std::pair<std::string, LibRecord> const& pair) { return pair.second; });
+
     // sort the libraries by their pss
-    std::sort(g_libs.begin(), g_libs.end(),
+    std::sort(v_libs.begin(), v_libs.end(),
               [](const LibRecord& l1, const LibRecord& l2) { return l1.pss() > l2.pss(); });
 
-    for (auto& lib : g_libs) {
+    for (auto& lib : v_libs) {
         printf("%6" PRIu64 "K   %7s   %6s   %6s   %6s  ", lib.pss() / 1024, "", "", "", "");
         if (g_has_swap) {
             printf(" %6s  ", "");
@@ -333,9 +328,15 @@
         printf("%s\n", lib.name().c_str());
 
         // sort all mappings first
-        lib.Sort(sort_func);
 
-        for (auto& p : lib.processes()) {
+        std::vector<ProcessRecord> procs;
+        procs.reserve(lib.processes().size());
+        std::transform(lib.processes().begin(), lib.processes().end(), std::back_inserter(procs),
+            [] (std::pair<pid_t, ProcessRecord> const& pair) { return pair.second; });
+
+        std::sort(procs.begin(), procs.end(), sort_func);
+
+        for (auto& p : procs) {
             const MemUsage& usage = p.usage();
             printf(" %6s  %7" PRIu64 "K  %6" PRIu64 "K  %6" PRIu64 "K  %6" PRIu64 "K  ", "",
                    usage.vss / 1024, usage.rss / 1024, usage.pss / 1024, usage.uss / 1024);
diff --git a/libnativeloader/Android.bp b/libnativeloader/Android.bp
index b806ae4..b9f0dbf 100644
--- a/libnativeloader/Android.bp
+++ b/libnativeloader/Android.bp
@@ -21,7 +21,6 @@
     shared_libs: [
         "libnativehelper",
         "liblog",
-        "libcutils",
         "libnativebridge",
         "libbase",
     ],
diff --git a/libnativeloader/native_loader.cpp b/libnativeloader/native_loader.cpp
index 09998f0..043f038 100644
--- a/libnativeloader/native_loader.cpp
+++ b/libnativeloader/native_loader.cpp
@@ -21,7 +21,6 @@
 #ifdef __ANDROID__
 #define LOG_TAG "libnativeloader"
 #include "nativeloader/dlext_namespaces.h"
-#include "cutils/properties.h"
 #include "log/log.h"
 #endif
 #include <dirent.h>
@@ -116,6 +115,8 @@
 
 static constexpr const char* kVndkNamespaceName = "vndk";
 
+static constexpr const char* kDefaultNamespaceName = "default";
+static constexpr const char* kPlatformNamespaceName = "platform";
 static constexpr const char* kRuntimeNamespaceName = "runtime";
 
 // classloader-namespace is a linker namespace that is created for the loaded
@@ -144,9 +145,11 @@
 #endif
 
 static bool is_debuggable() {
-  char debuggable[PROP_VALUE_MAX];
-  property_get("ro.debuggable", debuggable, "0");
-  return std::string(debuggable) == "1";
+  bool debuggable = false;
+#ifdef __BIONIC__
+  debuggable = android::base::GetBoolProperty("ro.debuggable", false);
+#endif
+  return debuggable;
 }
 
 static std::string vndk_version_str() {
@@ -271,8 +274,19 @@
 
     NativeLoaderNamespace native_loader_ns;
     if (!is_native_bridge) {
-      android_namespace_t* android_parent_ns =
-          parent_ns == nullptr ? nullptr : parent_ns->get_android_ns();
+      android_namespace_t* android_parent_ns;
+      if (parent_ns != nullptr) {
+        android_parent_ns = parent_ns->get_android_ns();
+      } else {
+        // Fall back to the platform namespace if no parent is found. It is
+        // called "default" for binaries in /system and "platform" for those in
+        // the Runtime APEX. Try "platform" first since "default" always exists.
+        android_parent_ns = android_get_exported_namespace(kPlatformNamespaceName);
+        if (android_parent_ns == nullptr) {
+          android_parent_ns = android_get_exported_namespace(kDefaultNamespaceName);
+        }
+      }
+
       android_namespace_t* ns = android_create_namespace(namespace_name,
                                                          nullptr,
                                                          library_path.c_str(),
@@ -321,8 +335,16 @@
 
       native_loader_ns = NativeLoaderNamespace(ns);
     } else {
-      native_bridge_namespace_t* native_bridge_parent_namespace =
-          parent_ns == nullptr ? nullptr : parent_ns->get_native_bridge_ns();
+      native_bridge_namespace_t* native_bridge_parent_namespace;
+      if (parent_ns != nullptr) {
+        native_bridge_parent_namespace = parent_ns->get_native_bridge_ns();
+      } else {
+        native_bridge_parent_namespace = NativeBridgeGetExportedNamespace(kPlatformNamespaceName);
+        if (native_bridge_parent_namespace == nullptr) {
+          native_bridge_parent_namespace = NativeBridgeGetExportedNamespace(kDefaultNamespaceName);
+        }
+      }
+
       native_bridge_namespace_t* ns = NativeBridgeCreateNamespace(namespace_name,
                                                                   nullptr,
                                                                   library_path.c_str(),
diff --git a/libprocessgroup/cgroup_map.cpp b/libprocessgroup/cgroup_map.cpp
index d094811..26d0754 100644
--- a/libprocessgroup/cgroup_map.cpp
+++ b/libprocessgroup/cgroup_map.cpp
@@ -45,6 +45,7 @@
 using android::base::unique_fd;
 
 static constexpr const char* CGROUPS_DESC_FILE = "/etc/cgroups.json";
+static constexpr const char* CGROUPS_DESC_VENDOR_FILE = "/vendor/etc/cgroups.json";
 
 static constexpr const char* CGROUP_PROCS_FILE = "/cgroup.procs";
 static constexpr const char* CGROUP_TASKS_FILE = "/tasks";
@@ -110,12 +111,13 @@
     return true;
 }
 
-static bool ReadDescriptors(std::map<std::string, CgroupDescriptor>* descriptors) {
+static bool ReadDescriptorsFromFile(const std::string& file_name,
+                                    std::map<std::string, CgroupDescriptor>* descriptors) {
     std::vector<CgroupDescriptor> result;
     std::string json_doc;
 
-    if (!android::base::ReadFileToString(CGROUPS_DESC_FILE, &json_doc)) {
-        LOG(ERROR) << "Failed to read task profiles from " << CGROUPS_DESC_FILE;
+    if (!android::base::ReadFileToString(file_name, &json_doc)) {
+        LOG(ERROR) << "Failed to read task profiles from " << file_name;
         return false;
     }
 
@@ -130,21 +132,46 @@
         const Json::Value& cgroups = root["Cgroups"];
         for (Json::Value::ArrayIndex i = 0; i < cgroups.size(); ++i) {
             std::string name = cgroups[i]["Controller"].asString();
-            descriptors->emplace(std::make_pair(
-                    name,
-                    CgroupDescriptor(1, name, cgroups[i]["Path"].asString(),
+            auto iter = descriptors->find(name);
+            if (iter == descriptors->end()) {
+                descriptors->emplace(name, CgroupDescriptor(1, name, cgroups[i]["Path"].asString(),
                                      std::strtoul(cgroups[i]["Mode"].asString().c_str(), 0, 8),
-                                     cgroups[i]["UID"].asString(), cgroups[i]["GID"].asString())));
+                                     cgroups[i]["UID"].asString(), cgroups[i]["GID"].asString()));
+            } else {
+                iter->second = CgroupDescriptor(1, name, cgroups[i]["Path"].asString(),
+                                     std::strtoul(cgroups[i]["Mode"].asString().c_str(), 0, 8),
+                                     cgroups[i]["UID"].asString(), cgroups[i]["GID"].asString());
+            }
         }
     }
 
     if (root.isMember("Cgroups2")) {
         const Json::Value& cgroups2 = root["Cgroups2"];
-        descriptors->emplace(std::make_pair(
-                CGROUPV2_CONTROLLER_NAME,
-                CgroupDescriptor(2, CGROUPV2_CONTROLLER_NAME, cgroups2["Path"].asString(),
+        auto iter = descriptors->find(CGROUPV2_CONTROLLER_NAME);
+        if (iter == descriptors->end()) {
+            descriptors->emplace(CGROUPV2_CONTROLLER_NAME, CgroupDescriptor(2, CGROUPV2_CONTROLLER_NAME, cgroups2["Path"].asString(),
                                  std::strtoul(cgroups2["Mode"].asString().c_str(), 0, 8),
-                                 cgroups2["UID"].asString(), cgroups2["GID"].asString())));
+                                 cgroups2["UID"].asString(), cgroups2["GID"].asString()));
+        } else {
+            iter->second = CgroupDescriptor(2, CGROUPV2_CONTROLLER_NAME, cgroups2["Path"].asString(),
+                                 std::strtoul(cgroups2["Mode"].asString().c_str(), 0, 8),
+                                 cgroups2["UID"].asString(), cgroups2["GID"].asString());
+        }
+    }
+
+    return true;
+}
+
+static bool ReadDescriptors(std::map<std::string, CgroupDescriptor>* descriptors) {
+    // load system cgroup descriptors
+    if (!ReadDescriptorsFromFile(CGROUPS_DESC_FILE, descriptors)) {
+        return false;
+    }
+
+    // load vendor cgroup descriptors if the file exists
+    if (!access(CGROUPS_DESC_VENDOR_FILE, F_OK) &&
+        !ReadDescriptorsFromFile(CGROUPS_DESC_VENDOR_FILE, descriptors)) {
+        return false;
     }
 
     return true;
diff --git a/libprocessgroup/processgroup.cpp b/libprocessgroup/processgroup.cpp
index 8505e61..8884650 100644
--- a/libprocessgroup/processgroup.cpp
+++ b/libprocessgroup/processgroup.cpp
@@ -170,8 +170,9 @@
     return ret;
 }
 
-static void RemoveUidProcessGroups(const std::string& uid_path) {
+static bool RemoveUidProcessGroups(const std::string& uid_path) {
     std::unique_ptr<DIR, decltype(&closedir)> uid(opendir(uid_path.c_str()), closedir);
+    bool empty = true;
     if (uid != NULL) {
         dirent* dir;
         while ((dir = readdir(uid.get())) != nullptr) {
@@ -185,9 +186,15 @@
 
             auto path = StringPrintf("%s/%s", uid_path.c_str(), dir->d_name);
             LOG(VERBOSE) << "Removing " << path;
-            if (rmdir(path.c_str()) == -1) PLOG(WARNING) << "Failed to remove " << path;
+            if (rmdir(path.c_str()) == -1) {
+                if (errno != EBUSY) {
+                    PLOG(WARNING) << "Failed to remove " << path;
+                }
+                empty = false;
+            }
         }
     }
+    return empty;
 }
 
 void removeAllProcessGroups() {
@@ -219,9 +226,14 @@
                 }
 
                 auto path = StringPrintf("%s/%s", cgroup_root_path.c_str(), dir->d_name);
-                RemoveUidProcessGroups(path);
+                if (!RemoveUidProcessGroups(path)) {
+                    LOG(VERBOSE) << "Skip removing " << path;
+                    continue;
+                }
                 LOG(VERBOSE) << "Removing " << path;
-                if (rmdir(path.c_str()) == -1) PLOG(WARNING) << "Failed to remove " << path;
+                if (rmdir(path.c_str()) == -1 && errno != EBUSY) {
+                    PLOG(WARNING) << "Failed to remove " << path;
+                }
             }
         }
     }
@@ -249,6 +261,10 @@
     auto path = ConvertUidPidToPath(cgroup, uid, initialPid) + PROCESSGROUP_CGROUP_PROCS_FILE;
     std::unique_ptr<FILE, decltype(&fclose)> fd(fopen(path.c_str(), "re"), fclose);
     if (!fd) {
+        if (errno == ENOENT) {
+            // This happens when process is already dead
+            return 0;
+        }
         PLOG(WARNING) << "Failed to open process cgroup uid " << uid << " pid " << initialPid;
         return -1;
     }
@@ -293,7 +309,7 @@
         LOG(VERBOSE) << "Killing process group " << -pgid << " in uid " << uid
                      << " as part of process cgroup " << initialPid;
 
-        if (kill(-pgid, signal) == -1) {
+        if (kill(-pgid, signal) == -1 && errno != ESRCH) {
             PLOG(WARNING) << "kill(" << -pgid << ", " << signal << ") failed";
         }
     }
@@ -303,7 +319,7 @@
         LOG(VERBOSE) << "Killing pid " << pid << " in uid " << uid << " as part of process cgroup "
                      << initialPid;
 
-        if (kill(pid, signal) == -1) {
+        if (kill(pid, signal) == -1 && errno != ESRCH) {
             PLOG(WARNING) << "kill(" << pid << ", " << signal << ") failed";
         }
     }
diff --git a/libprocessgroup/profiles/cgroups.json b/libprocessgroup/profiles/cgroups.json
index aa71956..5871a63 100644
--- a/libprocessgroup/profiles/cgroups.json
+++ b/libprocessgroup/profiles/cgroups.json
@@ -1,6 +1,13 @@
 {
   "Cgroups": [
     {
+      "Controller": "blkio",
+      "Path": "/dev/blkio",
+      "Mode": "0755",
+      "UID": "system",
+      "GID": "system"
+    },
+    {
       "Controller": "cpu",
       "Path": "/dev/cpuctl",
       "Mode": "0755",
diff --git a/libprocessgroup/profiles/task_profiles.json b/libprocessgroup/profiles/task_profiles.json
index 5a090c5..74a39cd 100644
--- a/libprocessgroup/profiles/task_profiles.json
+++ b/libprocessgroup/profiles/task_profiles.json
@@ -56,10 +56,10 @@
   "Profiles": [
     {
       "Name": "HighEnergySaving",
-      "Actions" : [
+      "Actions": [
         {
-          "Name" : "JoinCgroup",
-          "Params" :
+          "Name": "JoinCgroup",
+          "Params":
           {
             "Controller": "schedtune",
             "Path": "background"
@@ -69,10 +69,10 @@
     },
     {
       "Name": "NormalPerformance",
-      "Actions" : [
+      "Actions": [
         {
-          "Name" : "JoinCgroup",
-          "Params" :
+          "Name": "JoinCgroup",
+          "Params":
           {
             "Controller": "schedtune",
             "Path": ""
@@ -82,10 +82,10 @@
     },
     {
       "Name": "HighPerformance",
-      "Actions" : [
+      "Actions": [
         {
-          "Name" : "JoinCgroup",
-          "Params" :
+          "Name": "JoinCgroup",
+          "Params":
           {
             "Controller": "schedtune",
             "Path": "foreground"
@@ -95,10 +95,10 @@
     },
     {
       "Name": "MaxPerformance",
-      "Actions" : [
+      "Actions": [
         {
-          "Name" : "JoinCgroup",
-          "Params" :
+          "Name": "JoinCgroup",
+          "Params":
           {
             "Controller": "schedtune",
             "Path": "top-app"
@@ -108,10 +108,10 @@
     },
     {
       "Name": "RealtimePerformance",
-      "Actions" : [
+      "Actions": [
         {
-          "Name" : "JoinCgroup",
-          "Params" :
+          "Name": "JoinCgroup",
+          "Params":
           {
             "Controller": "schedtune",
             "Path": "rt"
@@ -122,26 +122,26 @@
 
     {
       "Name": "CpuPolicySpread",
-      "Actions" : [
+      "Actions": [
         {
-          "Name" : "SetAttribute",
-          "Params" :
+          "Name": "SetAttribute",
+          "Params":
           {
-            "Name" : "STunePreferIdle",
-            "Value" : "1"
+            "Name": "STunePreferIdle",
+            "Value": "1"
           }
         }
       ]
     },
     {
       "Name": "CpuPolicyPack",
-      "Actions" : [
+      "Actions": [
         {
-          "Name" : "SetAttribute",
-          "Params" :
+          "Name": "SetAttribute",
+          "Params":
           {
-            "Name" : "STunePreferIdle",
-            "Value" : "0"
+            "Name": "STunePreferIdle",
+            "Value": "0"
           }
         }
       ]
@@ -149,10 +149,10 @@
 
     {
       "Name": "VrKernelCapacity",
-      "Actions" : [
+      "Actions": [
         {
-          "Name" : "JoinCgroup",
-          "Params" :
+          "Name": "JoinCgroup",
+          "Params":
           {
             "Controller": "cpuset",
             "Path": ""
@@ -162,10 +162,10 @@
     },
     {
       "Name": "VrServiceCapacityLow",
-      "Actions" : [
+      "Actions": [
         {
-          "Name" : "JoinCgroup",
-          "Params" :
+          "Name": "JoinCgroup",
+          "Params":
           {
             "Controller": "cpuset",
             "Path": "system/background"
@@ -175,10 +175,10 @@
     },
     {
       "Name": "VrServiceCapacityNormal",
-      "Actions" : [
+      "Actions": [
         {
-          "Name" : "JoinCgroup",
-          "Params" :
+          "Name": "JoinCgroup",
+          "Params":
           {
             "Controller": "cpuset",
             "Path": "system"
@@ -188,10 +188,10 @@
     },
     {
       "Name": "VrServiceCapacityHigh",
-      "Actions" : [
+      "Actions": [
         {
-          "Name" : "JoinCgroup",
-          "Params" :
+          "Name": "JoinCgroup",
+          "Params":
           {
             "Controller": "cpuset",
             "Path": "system/performance"
@@ -201,10 +201,10 @@
     },
     {
       "Name": "VrProcessCapacityLow",
-      "Actions" : [
+      "Actions": [
         {
-          "Name" : "JoinCgroup",
-          "Params" :
+          "Name": "JoinCgroup",
+          "Params":
           {
             "Controller": "cpuset",
             "Path": "application/background"
@@ -214,10 +214,10 @@
     },
     {
       "Name": "VrProcessCapacityNormal",
-      "Actions" : [
+      "Actions": [
         {
-          "Name" : "JoinCgroup",
-          "Params" :
+          "Name": "JoinCgroup",
+          "Params":
           {
             "Controller": "cpuset",
             "Path": "application"
@@ -227,10 +227,10 @@
     },
     {
       "Name": "VrProcessCapacityHigh",
-      "Actions" : [
+      "Actions": [
         {
-          "Name" : "JoinCgroup",
-          "Params" :
+          "Name": "JoinCgroup",
+          "Params":
           {
             "Controller": "cpuset",
             "Path": "application/performance"
@@ -241,10 +241,10 @@
 
     {
       "Name": "ProcessCapacityLow",
-      "Actions" : [
+      "Actions": [
         {
-          "Name" : "JoinCgroup",
-          "Params" :
+          "Name": "JoinCgroup",
+          "Params":
           {
             "Controller": "cpuset",
             "Path": "background"
@@ -254,10 +254,10 @@
     },
     {
       "Name": "ProcessCapacityNormal",
-      "Actions" : [
+      "Actions": [
         {
-          "Name" : "JoinCgroup",
-          "Params" :
+          "Name": "JoinCgroup",
+          "Params":
           {
             "Controller": "cpuset",
             "Path": ""
@@ -267,10 +267,10 @@
     },
     {
       "Name": "ProcessCapacityHigh",
-      "Actions" : [
+      "Actions": [
         {
-          "Name" : "JoinCgroup",
-          "Params" :
+          "Name": "JoinCgroup",
+          "Params":
           {
             "Controller": "cpuset",
             "Path": "foreground"
@@ -280,10 +280,10 @@
     },
     {
       "Name": "ProcessCapacityMax",
-      "Actions" : [
+      "Actions": [
         {
-          "Name" : "JoinCgroup",
-          "Params" :
+          "Name": "JoinCgroup",
+          "Params":
           {
             "Controller": "cpuset",
             "Path": "top-app"
@@ -294,10 +294,10 @@
 
     {
       "Name": "ServiceCapacityLow",
-      "Actions" : [
+      "Actions": [
         {
-          "Name" : "JoinCgroup",
-          "Params" :
+          "Name": "JoinCgroup",
+          "Params":
           {
             "Controller": "cpuset",
             "Path": "system-background"
@@ -307,10 +307,10 @@
     },
     {
       "Name": "ServiceCapacityRestricted",
-      "Actions" : [
+      "Actions": [
         {
-          "Name" : "JoinCgroup",
-          "Params" :
+          "Name": "JoinCgroup",
+          "Params":
           {
             "Controller": "cpuset",
             "Path": "restricted"
@@ -321,10 +321,10 @@
 
     {
       "Name": "CameraServiceCapacity",
-      "Actions" : [
+      "Actions": [
         {
-          "Name" : "JoinCgroup",
-          "Params" :
+          "Name": "JoinCgroup",
+          "Params":
           {
             "Controller": "cpuset",
             "Path": "camera-daemon"
@@ -334,11 +334,64 @@
     },
 
     {
-      "Name": "TimerSlackHigh",
-      "Actions" : [
+      "Name": "LowIoPriority",
+      "Actions": [
         {
-          "Name" : "SetTimerSlack",
-          "Params" :
+          "Name": "JoinCgroup",
+          "Params":
+          {
+            "Controller": "blkio",
+            "Path": "background"
+          }
+        }
+      ]
+    },
+    {
+      "Name": "NormalIoPriority",
+      "Actions": [
+        {
+          "Name": "JoinCgroup",
+          "Params":
+          {
+            "Controller": "blkio",
+            "Path": ""
+          }
+        }
+      ]
+    },
+    {
+      "Name": "HighIoPriority",
+      "Actions": [
+        {
+          "Name": "JoinCgroup",
+          "Params":
+          {
+            "Controller": "blkio",
+            "Path": ""
+          }
+        }
+      ]
+    },
+    {
+      "Name": "MaxIoPriority",
+      "Actions": [
+        {
+          "Name": "JoinCgroup",
+          "Params":
+          {
+            "Controller": "blkio",
+            "Path": ""
+          }
+        }
+      ]
+    },
+
+    {
+      "Name": "TimerSlackHigh",
+      "Actions": [
+        {
+          "Name": "SetTimerSlack",
+          "Params":
           {
             "Slack": "40000000"
           }
@@ -347,10 +400,10 @@
     },
     {
       "Name": "TimerSlackNormal",
-      "Actions" : [
+      "Actions": [
         {
-          "Name" : "SetTimerSlack",
-          "Params" :
+          "Name": "SetTimerSlack",
+          "Params":
           {
             "Slack": "50000"
           }
@@ -360,26 +413,26 @@
 
     {
       "Name": "PerfBoost",
-      "Actions" : [
+      "Actions": [
         {
-          "Name" : "SetClamps",
-          "Params" :
+          "Name": "SetClamps",
+          "Params":
           {
-            "Boost" : "50%",
-            "Clamp" : "0"
+            "Boost": "50%",
+            "Clamp": "0"
           }
         }
       ]
     },
     {
       "Name": "PerfClamp",
-      "Actions" : [
+      "Actions": [
         {
-          "Name" : "SetClamps",
-          "Params" :
+          "Name": "SetClamps",
+          "Params":
           {
-            "Boost" : "0",
-            "Clamp" : "30%"
+            "Boost": "0",
+            "Clamp": "30%"
           }
         }
       ]
@@ -387,21 +440,21 @@
 
     {
       "Name": "LowMemoryUsage",
-      "Actions" : [
+      "Actions": [
         {
-          "Name" : "SetAttribute",
-          "Params" :
+          "Name": "SetAttribute",
+          "Params":
           {
-            "Name" : "MemSoftLimit",
-            "Value" : "16MB"
+            "Name": "MemSoftLimit",
+            "Value": "16MB"
           }
         },
         {
-          "Name" : "SetAttribute",
-          "Params" :
+          "Name": "SetAttribute",
+          "Params":
           {
-            "Name" : "MemSwappiness",
-            "Value" : "150"
+            "Name": "MemSwappiness",
+            "Value": "150"
 
           }
         }
@@ -409,31 +462,31 @@
     },
     {
       "Name": "HighMemoryUsage",
-      "Actions" : [
+      "Actions": [
         {
-          "Name" : "SetAttribute",
-          "Params" :
+          "Name": "SetAttribute",
+          "Params":
           {
-            "Name" : "MemSoftLimit",
-            "Value" : "512MB"
+            "Name": "MemSoftLimit",
+            "Value": "512MB"
           }
         },
         {
-          "Name" : "SetAttribute",
-          "Params" :
+          "Name": "SetAttribute",
+          "Params":
           {
-            "Name" : "MemSwappiness",
-            "Value" : "100"
+            "Name": "MemSwappiness",
+            "Value": "100"
           }
         }
       ]
     },
     {
       "Name": "SystemMemoryProcess",
-      "Actions" : [
+      "Actions": [
         {
-          "Name" : "JoinCgroup",
-          "Params" :
+          "Name": "JoinCgroup",
+          "Params":
           {
             "Controller": "memory",
             "Path": "system"
diff --git a/libprocessgroup/sched_policy.cpp b/libprocessgroup/sched_policy.cpp
index 337b032..026c011 100644
--- a/libprocessgroup/sched_policy.cpp
+++ b/libprocessgroup/sched_policy.cpp
@@ -46,20 +46,20 @@
 
     switch (policy) {
         case SP_BACKGROUND:
-            return SetTaskProfiles(tid,
-                                   {"HighEnergySaving", "ProcessCapacityLow", "TimerSlackHigh"})
+            return SetTaskProfiles(tid, {"HighEnergySaving", "ProcessCapacityLow", "LowIoPriority",
+                                         "TimerSlackHigh"})
                            ? 0
                            : -1;
         case SP_FOREGROUND:
         case SP_AUDIO_APP:
         case SP_AUDIO_SYS:
-            return SetTaskProfiles(tid,
-                                   {"HighPerformance", "ProcessCapacityHigh", "TimerSlackNormal"})
+            return SetTaskProfiles(tid, {"HighPerformance", "ProcessCapacityHigh", "HighIoPriority",
+                                         "TimerSlackNormal"})
                            ? 0
                            : -1;
         case SP_TOP_APP:
-            return SetTaskProfiles(tid,
-                                   {"MaxPerformance", "ProcessCapacityMax", "TimerSlackNormal"})
+            return SetTaskProfiles(tid, {"MaxPerformance", "ProcessCapacityMax", "MaxIoPriority",
+                                         "TimerSlackNormal"})
                            ? 0
                            : -1;
         case SP_SYSTEM:
@@ -126,15 +126,24 @@
 
     switch (policy) {
         case SP_BACKGROUND:
-            return SetTaskProfiles(tid, {"HighEnergySaving", "TimerSlackHigh"}) ? 0 : -1;
+            return SetTaskProfiles(tid, {"HighEnergySaving", "LowIoPriority", "TimerSlackHigh"})
+                           ? 0
+                           : -1;
         case SP_FOREGROUND:
         case SP_AUDIO_APP:
         case SP_AUDIO_SYS:
-            return SetTaskProfiles(tid, {"HighPerformance", "TimerSlackNormal"}) ? 0 : -1;
+            return SetTaskProfiles(tid, {"HighPerformance", "HighIoPriority", "TimerSlackNormal"})
+                           ? 0
+                           : -1;
         case SP_TOP_APP:
-            return SetTaskProfiles(tid, {"MaxPerformance", "TimerSlackNormal"}) ? 0 : -1;
+            return SetTaskProfiles(tid, {"MaxPerformance", "MaxIoPriority", "TimerSlackNormal"})
+                           ? 0
+                           : -1;
         case SP_RT_APP:
-            return SetTaskProfiles(tid, {"RealtimePerformance", "TimerSlackNormal"}) ? 0 : -1;
+            return SetTaskProfiles(tid,
+                                   {"RealtimePerformance", "MaxIoPriority", "TimerSlackNormal"})
+                           ? 0
+                           : -1;
         default:
             return SetTaskProfiles(tid, {"TimerSlackNormal"}) ? 0 : -1;
     }
diff --git a/libprocessgroup/task_profiles.cpp b/libprocessgroup/task_profiles.cpp
index b69103c..fded417 100644
--- a/libprocessgroup/task_profiles.cpp
+++ b/libprocessgroup/task_profiles.cpp
@@ -42,6 +42,7 @@
 using android::base::WriteStringToFile;
 
 #define TASK_PROFILE_DB_FILE "/etc/task_profiles.json"
+#define TASK_PROFILE_DB_VENDOR_FILE "/vendor/etc/task_profiles.json"
 
 bool ProfileAttribute::GetPathForTask(int tid, std::string* path) const {
     std::string subgroup;
@@ -198,7 +199,7 @@
     }
 
     // this is app-dependent path, file descriptor is not cached
-    std::string procs_path = controller_->GetProcsFilePath(path_.c_str(), uid, pid);
+    std::string procs_path = controller_->GetProcsFilePath(path_, uid, pid);
     unique_fd tmp_fd(TEMP_FAILURE_RETRY(open(procs_path.c_str(), O_WRONLY | O_CLOEXEC)));
     if (tmp_fd < 0) {
         PLOG(WARNING) << "Failed to open " << procs_path << ": " << strerror(errno);
@@ -211,7 +212,7 @@
 
     return true;
 #else
-    std::string procs_path = controller_->GetProcsFilePath(path_.c_str(), uid, pid);
+    std::string procs_path = controller_->GetProcsFilePath(path_, uid, pid);
     unique_fd tmp_fd(TEMP_FAILURE_RETRY(open(procs_path.c_str(), O_WRONLY | O_CLOEXEC)));
     if (tmp_fd < 0) {
         // no permissions to access the file, ignore
@@ -246,7 +247,7 @@
     PLOG(ERROR) << "Application profile can't be applied to a thread";
     return false;
 #else
-    std::string tasks_path = controller_->GetTasksFilePath(path_.c_str());
+    std::string tasks_path = controller_->GetTasksFilePath(path_);
     unique_fd tmp_fd(TEMP_FAILURE_RETRY(open(tasks_path.c_str(), O_WRONLY | O_CLOEXEC)));
     if (tmp_fd < 0) {
         // no permissions to access the file, ignore
@@ -288,16 +289,24 @@
 }
 
 TaskProfiles::TaskProfiles() {
-    if (!Load(CgroupMap::GetInstance())) {
-        LOG(ERROR) << "TaskProfiles::Load for [" << getpid() << "] failed";
+    // load system task profiles
+    if (!Load(CgroupMap::GetInstance(), TASK_PROFILE_DB_FILE)) {
+        LOG(ERROR) << "Loading " << TASK_PROFILE_DB_FILE << " for [" << getpid() << "] failed";
+    }
+
+    // load vendor task profiles if the file exists
+    if (!access(TASK_PROFILE_DB_VENDOR_FILE, F_OK) &&
+        !Load(CgroupMap::GetInstance(), TASK_PROFILE_DB_VENDOR_FILE)) {
+        LOG(ERROR) << "Loading " << TASK_PROFILE_DB_VENDOR_FILE << " for [" << getpid()
+                   << "] failed";
     }
 }
 
-bool TaskProfiles::Load(const CgroupMap& cg_map) {
+bool TaskProfiles::Load(const CgroupMap& cg_map, const std::string& file_name) {
     std::string json_doc;
 
-    if (!android::base::ReadFileToString(TASK_PROFILE_DB_FILE, &json_doc)) {
-        LOG(ERROR) << "Failed to read task profiles from " << TASK_PROFILE_DB_FILE;
+    if (!android::base::ReadFileToString(file_name, &json_doc)) {
+        LOG(ERROR) << "Failed to read task profiles from " << file_name;
         return false;
     }
 
@@ -308,18 +317,18 @@
         return false;
     }
 
-    Json::Value attr = root["Attributes"];
+    const Json::Value& attr = root["Attributes"];
     for (Json::Value::ArrayIndex i = 0; i < attr.size(); ++i) {
         std::string name = attr[i]["Name"].asString();
-        std::string ctrlName = attr[i]["Controller"].asString();
-        std::string file_name = attr[i]["File"].asString();
+        std::string controller_name = attr[i]["Controller"].asString();
+        std::string file_attr = attr[i]["File"].asString();
 
         if (attributes_.find(name) == attributes_.end()) {
-            const CgroupController* controller = cg_map.FindController(ctrlName.c_str());
+            const CgroupController* controller = cg_map.FindController(controller_name);
             if (controller) {
-                attributes_[name] = std::make_unique<ProfileAttribute>(controller, file_name);
+                attributes_[name] = std::make_unique<ProfileAttribute>(controller, file_attr);
             } else {
-                LOG(WARNING) << "Controller " << ctrlName << " is not found";
+                LOG(WARNING) << "Controller " << controller_name << " is not found";
             }
         } else {
             LOG(WARNING) << "Attribute " << name << " is already defined";
@@ -328,72 +337,72 @@
 
     std::map<std::string, std::string> params;
 
-    Json::Value profilesVal = root["Profiles"];
-    for (Json::Value::ArrayIndex i = 0; i < profilesVal.size(); ++i) {
-        Json::Value profileVal = profilesVal[i];
+    const Json::Value& profiles_val = root["Profiles"];
+    for (Json::Value::ArrayIndex i = 0; i < profiles_val.size(); ++i) {
+        const Json::Value& profile_val = profiles_val[i];
 
-        std::string profileName = profileVal["Name"].asString();
-        Json::Value actions = profileVal["Actions"];
+        std::string profile_name = profile_val["Name"].asString();
+        const Json::Value& actions = profile_val["Actions"];
         auto profile = std::make_unique<TaskProfile>();
 
-        for (Json::Value::ArrayIndex actIdx = 0; actIdx < actions.size(); ++actIdx) {
-            Json::Value actionVal = actions[actIdx];
-            std::string actionName = actionVal["Name"].asString();
-            Json::Value paramsVal = actionVal["Params"];
-            if (actionName == "JoinCgroup") {
-                std::string ctrlName = paramsVal["Controller"].asString();
-                std::string path = paramsVal["Path"].asString();
+        for (Json::Value::ArrayIndex act_idx = 0; act_idx < actions.size(); ++act_idx) {
+            const Json::Value& action_val = actions[act_idx];
+            std::string action_name = action_val["Name"].asString();
+            const Json::Value& params_val = action_val["Params"];
+            if (action_name == "JoinCgroup") {
+                std::string controller_name = params_val["Controller"].asString();
+                std::string path = params_val["Path"].asString();
 
-                const CgroupController* controller = cg_map.FindController(ctrlName.c_str());
+                const CgroupController* controller = cg_map.FindController(controller_name);
                 if (controller) {
                     profile->Add(std::make_unique<SetCgroupAction>(controller, path));
                 } else {
-                    LOG(WARNING) << "JoinCgroup: controller " << ctrlName << " is not found";
+                    LOG(WARNING) << "JoinCgroup: controller " << controller_name << " is not found";
                 }
-            } else if (actionName == "SetTimerSlack") {
-                std::string slackValue = paramsVal["Slack"].asString();
+            } else if (action_name == "SetTimerSlack") {
+                std::string slack_value = params_val["Slack"].asString();
                 char* end;
                 unsigned long slack;
 
-                slack = strtoul(slackValue.c_str(), &end, 10);
-                if (end > slackValue.c_str()) {
+                slack = strtoul(slack_value.c_str(), &end, 10);
+                if (end > slack_value.c_str()) {
                     profile->Add(std::make_unique<SetTimerSlackAction>(slack));
                 } else {
-                    LOG(WARNING) << "SetTimerSlack: invalid parameter: " << slackValue;
+                    LOG(WARNING) << "SetTimerSlack: invalid parameter: " << slack_value;
                 }
-            } else if (actionName == "SetAttribute") {
-                std::string attrName = paramsVal["Name"].asString();
-                std::string attrValue = paramsVal["Value"].asString();
+            } else if (action_name == "SetAttribute") {
+                std::string attr_name = params_val["Name"].asString();
+                std::string attr_value = params_val["Value"].asString();
 
-                auto iter = attributes_.find(attrName);
+                auto iter = attributes_.find(attr_name);
                 if (iter != attributes_.end()) {
                     profile->Add(
-                            std::make_unique<SetAttributeAction>(iter->second.get(), attrValue));
+                            std::make_unique<SetAttributeAction>(iter->second.get(), attr_value));
                 } else {
-                    LOG(WARNING) << "SetAttribute: unknown attribute: " << attrName;
+                    LOG(WARNING) << "SetAttribute: unknown attribute: " << attr_name;
                 }
-            } else if (actionName == "SetClamps") {
-                std::string boostValue = paramsVal["Boost"].asString();
-                std::string clampValue = paramsVal["Clamp"].asString();
+            } else if (action_name == "SetClamps") {
+                std::string boost_value = params_val["Boost"].asString();
+                std::string clamp_value = params_val["Clamp"].asString();
                 char* end;
                 unsigned long boost;
 
-                boost = strtoul(boostValue.c_str(), &end, 10);
-                if (end > boostValue.c_str()) {
-                    unsigned long clamp = strtoul(clampValue.c_str(), &end, 10);
-                    if (end > clampValue.c_str()) {
+                boost = strtoul(boost_value.c_str(), &end, 10);
+                if (end > boost_value.c_str()) {
+                    unsigned long clamp = strtoul(clamp_value.c_str(), &end, 10);
+                    if (end > clamp_value.c_str()) {
                         profile->Add(std::make_unique<SetClampsAction>(boost, clamp));
                     } else {
-                        LOG(WARNING) << "SetClamps: invalid parameter " << clampValue;
+                        LOG(WARNING) << "SetClamps: invalid parameter " << clamp_value;
                     }
                 } else {
-                    LOG(WARNING) << "SetClamps: invalid parameter: " << boostValue;
+                    LOG(WARNING) << "SetClamps: invalid parameter: " << boost_value;
                 }
             } else {
-                LOG(WARNING) << "Unknown profile action: " << actionName;
+                LOG(WARNING) << "Unknown profile action: " << action_name;
             }
         }
-        profiles_[profileName] = std::move(profile);
+        profiles_[profile_name] = std::move(profile);
     }
 
     return true;
diff --git a/libprocessgroup/task_profiles.h b/libprocessgroup/task_profiles.h
index b2e39f9..9ee81c1 100644
--- a/libprocessgroup/task_profiles.h
+++ b/libprocessgroup/task_profiles.h
@@ -152,5 +152,5 @@
 
     TaskProfiles();
 
-    bool Load(const CgroupMap& cg_map);
+    bool Load(const CgroupMap& cg_map, const std::string& file_name);
 };
diff --git a/libunwindstack/Android.bp b/libunwindstack/Android.bp
index c90f5b2..a49fd9e 100644
--- a/libunwindstack/Android.bp
+++ b/libunwindstack/Android.bp
@@ -95,7 +95,6 @@
                 "DexFiles.cpp",
             ],
             exclude_shared_libs: [
-                "libdexfile_external",
                 "libdexfile_support",
             ],
         },
@@ -106,7 +105,6 @@
                 "DexFiles.cpp",
             ],
             exclude_shared_libs: [
-                "libdexfile_external",
                 "libdexfile_support",
             ],
         },
@@ -137,7 +135,6 @@
 
     shared_libs: [
         "libbase",
-        "libdexfile_external",
         "libdexfile_support",
         "liblog",
         "liblzma",
diff --git a/libutils/Android.bp b/libutils/Android.bp
index 93aa1e6..c67ff8f 100644
--- a/libutils/Android.bp
+++ b/libutils/Android.bp
@@ -205,7 +205,6 @@
         "LruCache_test.cpp",
         "Mutex_test.cpp",
         "SharedBuffer_test.cpp",
-        "Singleton_test.cpp",
         "String8_test.cpp",
         "StrongPointer_test.cpp",
         "Unicode_test.cpp",
@@ -240,17 +239,33 @@
         },
     },
 
-    required: [
-        "libutils_test_singleton1",
-        "libutils_test_singleton2",
-    ],
-
     cflags: [
         "-Wall",
         "-Wextra",
         "-Werror",
         "-Wthread-safety",
     ],
+
+    test_suites: ["device-tests"],
+}
+
+// TODO: the test infrastructure isn't yet capable of running this,
+// so it's broken out into its own test so that the main libutils_tests
+// can be in presubmit even if this can't.
+
+cc_test {
+    name: "libutils_singleton_test",
+    srcs: ["Singleton_test.cpp"],
+    cflags: [
+        "-Wall",
+        "-Werror",
+    ],
+    shared_libs: ["libbase"],
+
+    required: [
+        ":libutils_test_singleton1",
+        ":libutils_test_singleton2",
+    ],
 }
 
 cc_test_library {
diff --git a/lmkd/lmkd.c b/lmkd/lmkd.c
index 562e578..18421e8 100644
--- a/lmkd/lmkd.c
+++ b/lmkd/lmkd.c
@@ -1329,7 +1329,7 @@
 static int last_killed_pid = -1;
 
 /* Kill one process specified by procp.  Returns the size of the process killed */
-static int kill_one_process(struct proc* procp) {
+static int kill_one_process(struct proc* procp, int min_oom_score) {
     int pid = procp->pid;
     uid_t uid = procp->uid;
     char *taskname;
@@ -1340,6 +1340,9 @@
 #ifdef LMKD_LOG_STATS
     struct memory_stat mem_st = {};
     int memory_stat_parse_result = -1;
+#else
+    /* To prevent unused parameter warning */
+    (void)(min_oom_score);
 #endif
 
     taskname = proc_get_name(pid);
@@ -1385,10 +1388,12 @@
         if (memory_stat_parse_result == 0) {
             stats_write_lmk_kill_occurred(log_ctx, LMK_KILL_OCCURRED, uid, taskname,
                     procp->oomadj, mem_st.pgfault, mem_st.pgmajfault, mem_st.rss_in_bytes,
-                    mem_st.cache_in_bytes, mem_st.swap_in_bytes, mem_st.process_start_time_ns);
+                    mem_st.cache_in_bytes, mem_st.swap_in_bytes, mem_st.process_start_time_ns,
+                    min_oom_score);
         } else if (enable_stats_log) {
             stats_write_lmk_kill_occurred(log_ctx, LMK_KILL_OCCURRED, uid, taskname, procp->oomadj,
-                                          -1, -1, tasksize * BYTES_IN_KILOBYTE, -1, -1, -1);
+                                          -1, -1, tasksize * BYTES_IN_KILOBYTE, -1, -1, -1,
+                                          min_oom_score);
         }
 #endif
         result = tasksize;
@@ -1425,7 +1430,7 @@
             if (!procp)
                 break;
 
-            killed_size = kill_one_process(procp);
+            killed_size = kill_one_process(procp, min_score_adj);
             if (killed_size >= 0) {
 #ifdef LMKD_LOG_STATS
                 if (enable_stats_log && !lmk_state_change_start) {
@@ -1694,16 +1699,6 @@
         static unsigned long report_skip_count = 0;
 
         if (!use_minfree_levels) {
-            /* If pressure level is less than critical and enough free swap then ignore */
-            if (level < VMPRESS_LEVEL_CRITICAL &&
-                mi.field.free_swap > low_pressure_mem.max_nr_free_pages) {
-                if (debug_process_killing) {
-                    ALOGI("Ignoring pressure since %" PRId64
-                          " swap pages are available ",
-                          mi.field.free_swap);
-                }
-                return;
-            }
             /* Free up enough memory to downgrate the memory pressure to low level */
             if (mi.field.nr_free_pages >= low_pressure_mem.max_nr_free_pages) {
                 if (debug_process_killing) {
diff --git a/lmkd/statslog.c b/lmkd/statslog.c
index 689e8ae..0c230ae 100644
--- a/lmkd/statslog.c
+++ b/lmkd/statslog.c
@@ -65,7 +65,8 @@
 stats_write_lmk_kill_occurred(android_log_context ctx, int32_t code, int32_t uid,
                               char const* process_name, int32_t oom_score, int64_t pgfault,
                               int64_t pgmajfault, int64_t rss_in_bytes, int64_t cache_in_bytes,
-                              int64_t swap_in_bytes, int64_t process_start_time_ns) {
+                              int64_t swap_in_bytes, int64_t process_start_time_ns,
+                              int32_t min_oom_score) {
     assert(ctx != NULL);
     int ret = -EINVAL;
     if (!ctx) {
@@ -117,5 +118,9 @@
         return ret;
     }
 
+    if ((ret = android_log_write_int32(ctx, min_oom_score)) < 0) {
+        return ret;
+    }
+
     return write_to_logger(ctx, LOG_ID_STATS);
 }
diff --git a/lmkd/statslog.h b/lmkd/statslog.h
index f3abe11..2edba7a 100644
--- a/lmkd/statslog.h
+++ b/lmkd/statslog.h
@@ -88,7 +88,8 @@
 stats_write_lmk_kill_occurred(android_log_context ctx, int32_t code, int32_t uid,
                               char const* process_name, int32_t oom_score, int64_t pgfault,
                               int64_t pgmajfault, int64_t rss_in_bytes, int64_t cache_in_bytes,
-                              int64_t swap_in_bytes, int64_t process_start_time_ns);
+                              int64_t swap_in_bytes, int64_t process_start_time_ns,
+                              int32_t min_oom_score);
 
 __END_DECLS
 
diff --git a/rootdir/Android.mk b/rootdir/Android.mk
index 944554a..d2125d8 100644
--- a/rootdir/Android.mk
+++ b/rootdir/Android.mk
@@ -44,6 +44,7 @@
 
 # TODO(b/124106384): Clean up compat symlinks for ART binaries.
 ART_BINARIES= \
+  dalvikvm \
   dalvikvm32 \
   dalvikvm64 \
   dex2oat \
@@ -190,6 +191,7 @@
 	@echo "Generate: $< -> $@"
 	@mkdir -p $(dir $@)
 	$(hide) sed -e 's?%BOOTCLASSPATH%?$(PRODUCT_BOOTCLASSPATH)?g' $< >$@
+	$(hide) sed -i -e 's?%DEX2OATBOOTCLASSPATH%?$(PRODUCT_DEX2OAT_BOOTCLASSPATH)?g' $@
 	$(hide) sed -i -e 's?%SYSTEMSERVERCLASSPATH%?$(PRODUCT_SYSTEM_SERVER_CLASSPATH)?g' $@
 	$(hide) sed -i -e 's?%EXPORT_GLOBAL_ASAN_OPTIONS%?$(EXPORT_GLOBAL_ASAN_OPTIONS)?g' $@
 	$(hide) sed -i -e 's?%EXPORT_GLOBAL_GCOV_OPTIONS%?$(EXPORT_GLOBAL_GCOV_OPTIONS)?g' $@
diff --git a/rootdir/etc/ld.config.legacy.txt b/rootdir/etc/ld.config.legacy.txt
index fa0a01a..0cde3f2 100644
--- a/rootdir/etc/ld.config.legacy.txt
+++ b/rootdir/etc/ld.config.legacy.txt
@@ -91,6 +91,8 @@
 namespace.media.search.paths = /apex/com.android.media/${LIB}
 namespace.media.asan.search.paths = /apex/com.android.media/${LIB}
 
+namespace.media.permitted.paths = /apex/com.android.media/${LIB}/extractors
+
 namespace.media.links = default
 namespace.media.link.default.shared_libs  = %LLNDK_LIBRARIES%
 namespace.media.link.default.shared_libs += libandroid.so
diff --git a/rootdir/etc/ld.config.txt b/rootdir/etc/ld.config.txt
index cf834f0..4b2dd07 100644
--- a/rootdir/etc/ld.config.txt
+++ b/rootdir/etc/ld.config.txt
@@ -68,6 +68,9 @@
 namespace.default.permitted.paths += /vendor/framework
 namespace.default.permitted.paths += /vendor/app
 namespace.default.permitted.paths += /vendor/priv-app
+namespace.default.permitted.paths += /system/vendor/framework
+namespace.default.permitted.paths += /system/vendor/app
+namespace.default.permitted.paths += /system/vendor/priv-app
 namespace.default.permitted.paths += /odm/framework
 namespace.default.permitted.paths += /odm/app
 namespace.default.permitted.paths += /odm/priv-app
@@ -100,6 +103,9 @@
 namespace.default.asan.permitted.paths += /vendor/framework
 namespace.default.asan.permitted.paths += /vendor/app
 namespace.default.asan.permitted.paths += /vendor/priv-app
+namespace.default.asan.permitted.paths += /system/vendor/framework
+namespace.default.asan.permitted.paths += /system/vendor/app
+namespace.default.asan.permitted.paths += /system/vendor/priv-app
 namespace.default.asan.permitted.paths += /odm/framework
 namespace.default.asan.permitted.paths += /odm/app
 namespace.default.asan.permitted.paths += /odm/priv-app
@@ -169,6 +175,8 @@
 namespace.media.search.paths = /apex/com.android.media/${LIB}
 namespace.media.asan.search.paths = /apex/com.android.media/${LIB}
 
+namespace.media.permitted.paths = /apex/com.android.media/${LIB}/extractors
+
 namespace.media.links = default
 namespace.media.link.default.shared_libs  = %LLNDK_LIBRARIES%
 namespace.media.link.default.shared_libs += libandroid.so
@@ -234,6 +242,7 @@
 
 namespace.sphal.permitted.paths  = /odm/${LIB}
 namespace.sphal.permitted.paths += /vendor/${LIB}
+namespace.sphal.permitted.paths += /system/vendor/${LIB}
 
 namespace.sphal.asan.search.paths  = /data/asan/odm/${LIB}
 namespace.sphal.asan.search.paths +=           /odm/${LIB}
@@ -276,6 +285,7 @@
 
 namespace.rs.permitted.paths  = /odm/${LIB}
 namespace.rs.permitted.paths += /vendor/${LIB}
+namespace.rs.permitted.paths += /system/vendor/${LIB}
 namespace.rs.permitted.paths += /data
 
 namespace.rs.asan.search.paths  = /data/asan/odm/${LIB}/vndk-sp
@@ -321,6 +331,8 @@
 namespace.vndk.permitted.paths += /odm/${LIB}/egl
 namespace.vndk.permitted.paths += /vendor/${LIB}/hw
 namespace.vndk.permitted.paths += /vendor/${LIB}/egl
+namespace.vndk.permitted.paths += /system/vendor/${LIB}/hw
+namespace.vndk.permitted.paths += /system/vendor/${LIB}/egl
 # This is exceptionally required since android.hidl.memory@1.0-impl.so is here
 namespace.vndk.permitted.paths += /system/${LIB}/vndk-sp%VNDK_VER%/hw
 
@@ -388,6 +400,7 @@
 
 namespace.default.permitted.paths  = /odm
 namespace.default.permitted.paths += /vendor
+namespace.default.permitted.paths += /system/vendor
 #VNDK27#namespace.default.search.paths += /vendor/${LIB}/hw
 #VNDK27#namespace.default.search.paths += /vendor/${LIB}/egl
 
@@ -553,6 +566,8 @@
 namespace.media.search.paths = /apex/com.android.media/${LIB}
 namespace.media.asan.search.paths = /apex/com.android.media/${LIB}
 
+namespace.media.permitted.paths = /apex/com.android.media/${LIB}/extractors
+
 namespace.media.links = default
 namespace.media.link.default.shared_libs  = %LLNDK_LIBRARIES%
 namespace.media.link.default.shared_libs += libandroid.so
diff --git a/rootdir/etc/ld.config.vndk_lite.txt b/rootdir/etc/ld.config.vndk_lite.txt
index 2c6e01f..54f4c98 100644
--- a/rootdir/etc/ld.config.vndk_lite.txt
+++ b/rootdir/etc/ld.config.vndk_lite.txt
@@ -117,6 +117,8 @@
 namespace.media.search.paths = /apex/com.android.media/${LIB}
 namespace.media.asan.search.paths = /apex/com.android.media/${LIB}
 
+namespace.media.permitted.paths = /apex/com.android.media/${LIB}/extractors
+
 namespace.media.links = default
 namespace.media.link.default.shared_libs  = %LLNDK_LIBRARIES%
 namespace.media.link.default.shared_libs += libandroid.so
@@ -182,6 +184,7 @@
 
 namespace.sphal.permitted.paths  = /odm/${LIB}
 namespace.sphal.permitted.paths += /vendor/${LIB}
+namespace.sphal.permitted.paths += /system/vendor/${LIB}
 
 namespace.sphal.asan.search.paths  = /data/asan/odm/${LIB}
 namespace.sphal.asan.search.paths +=           /odm/${LIB}
@@ -224,6 +227,7 @@
 
 namespace.rs.permitted.paths  = /odm/${LIB}
 namespace.rs.permitted.paths += /vendor/${LIB}
+namespace.rs.permitted.paths += /system/vendor/${LIB}
 namespace.rs.permitted.paths += /data
 
 namespace.rs.asan.search.paths  = /data/asan/odm/${LIB}/vndk-sp
@@ -269,6 +273,7 @@
 namespace.vndk.permitted.paths += /odm/${LIB}/egl
 namespace.vndk.permitted.paths += /vendor/${LIB}/hw
 namespace.vndk.permitted.paths += /vendor/${LIB}/egl
+namespace.vndk.permitted.paths += /system/vendor/${LIB}/egl
 # This is exceptionally required since android.hidl.memory@1.0-impl.so is here
 namespace.vndk.permitted.paths += /system/${LIB}/vndk-sp%VNDK_VER%/hw
 
@@ -434,6 +439,8 @@
 namespace.media.search.paths = /apex/com.android.media/${LIB}
 namespace.media.asan.search.paths = /apex/com.android.media/${LIB}
 
+namespace.media.permitted.paths = /apex/com.android.media/${LIB}/extractors
+
 namespace.media.links = default
 namespace.media.link.default.shared_libs  = %LLNDK_LIBRARIES%
 namespace.media.link.default.shared_libs += libandroid.so
diff --git a/rootdir/init.environ.rc.in b/rootdir/init.environ.rc.in
index d5665f2..5d6cd2d 100644
--- a/rootdir/init.environ.rc.in
+++ b/rootdir/init.environ.rc.in
@@ -9,6 +9,7 @@
     export EXTERNAL_STORAGE /sdcard
     export ASEC_MOUNTPOINT /mnt/asec
     export BOOTCLASSPATH %BOOTCLASSPATH%
+    export DEX2OATBOOTCLASSPATH %DEX2OATBOOTCLASSPATH%
     export SYSTEMSERVERCLASSPATH %SYSTEMSERVERCLASSPATH%
     %EXPORT_GLOBAL_ASAN_OPTIONS%
     %EXPORT_GLOBAL_GCOV_OPTIONS%
diff --git a/rootdir/init.rc b/rootdir/init.rc
index 8bd7c4c..b44cc3e 100644
--- a/rootdir/init.rc
+++ b/rootdir/init.rc
@@ -13,12 +13,6 @@
 
 # Cgroups are mounted right before early-init using list from /etc/cgroups.json
 on early-init
-    # Mount shared so changes propagate into child namespaces
-    # Do this before other processes are started from init. Otherwise,
-    # processes launched while the propagation type of / is 'private'
-    # won't get mount events from others.
-    mount rootfs rootfs / shared rec
-
     # Set init and its forked children's oom_adj.
     write /proc/1/oom_score_adj -1000
 
@@ -43,6 +37,11 @@
 
     start ueventd
 
+    # Run apexd-bootstrap so that APEXes that provide critical libraries
+    # become available. Note that this is executed as exec_start to ensure that
+    # the libraries are available to the processes started after this statement.
+    exec_start apexd-bootstrap
+
 on init
     sysclktz 0
 
@@ -84,6 +83,15 @@
     chmod 0664 /dev/stune/top-app/tasks
     chmod 0664 /dev/stune/rt/tasks
 
+    # Create blkio tuning nodes
+    mkdir /dev/blkio/background
+    chown system system /dev/blkio
+    chown system system /dev/blkio/background
+    chown system system /dev/blkio/tasks
+    chown system system /dev/blkio/background/tasks
+    chmod 0664 /dev/blkio/tasks
+    chmod 0664 /dev/blkio/background/tasks
+
     restorecon_recursive /mnt
 
     mount configfs none /config nodev noexec nosuid
@@ -269,18 +277,9 @@
     write /dev/cpu_variant:${ro.bionic.2nd_arch} ${ro.bionic.2nd_cpu_variant}
     chmod 0444 /dev/cpu_variant:${ro.bionic.2nd_arch}
 
-    # Setup APEX mount point and its security context
-    mount tmpfs tmpfs /apex nodev noexec nosuid
-    chmod 0755 /apex
-    chown root root /apex
-    restorecon /apex
-
     # Start logd before any other services run to ensure we capture all of their logs.
     start logd
 
-    # Start apexd as soon as we can
-    start apexd
-
     # Start essential services.
     start servicemanager
     start hwservicemanager
@@ -416,8 +415,16 @@
     mkdir /data/bootchart 0755 shell shell
     bootchart start
 
-    # /data/apex is now available. Let apexd to scan and activate APEXes.
-    setprop apexd.data.status ready
+    # Make sure that apexd is started in the default namespace
+    enter_default_mount_ns
+
+    # /data/apex is now available. Start apexd to scan and activate APEXes.
+    mkdir /data/apex 0750 root system
+    mkdir /data/apex/active 0750 root system
+    mkdir /data/apex/backup 0700 root system
+    mkdir /data/apex/sessions 0700 root system
+    mkdir /data/pkg_staging 0750 system system
+    start apexd
 
     # Avoid predictable entropy pool. Carry over entropy from previous boot.
     copy /data/system/entropy.dat /dev/urandom
@@ -534,12 +541,6 @@
 
     mkdir /data/anr 0775 system system
 
-    mkdir /data/apex 0750 root system
-    mkdir /data/apex/active 0750 root system
-    mkdir /data/apex/backup 0700 root system
-    mkdir /data/apex/sessions 0700 root system
-    mkdir /data/pkg_staging 0750 system system
-
     # NFC: create data/nfc for nv storage
     mkdir /data/nfc 0770 nfc nfc
     mkdir /data/nfc/param 0770 nfc nfc
@@ -572,24 +573,22 @@
     mkdir /data/cache/backup_stage 0700 system system
     mkdir /data/cache/backup 0700 system system
 
+    # Wait for apexd to finish activating APEXes before starting more processes.
+    wait_for_prop apexd.status ready
+    # TODO(jiyong): remove setup_runtime_bionic
+    setup_runtime_bionic
+    parse_apex_configs
+
     init_user0
 
     # Set SELinux security contexts on upgrade or policy update.
     restorecon --recursive --skip-ce /data
 
-    # Check any timezone data in /data is newer than the copy in the runtime module, delete if not.
-    exec - system system -- /system/bin/tzdatacheck /apex/com.android.runtime/etc/tz /data/misc/zoneinfo
-
     # load fsverity keys
     exec -- /system/bin/mini-keyctl -c /product/etc/security/cacerts_fsverity,/vendor/etc/security/cacerts_fsverity -k .fs-verity
 
-    # Wait for apexd to finish activating APEXes before starting more processes.
-    # This certainly reduces the parallelism but is required to make as many processes
-    # as possible to use the bionic libs from the runtime APEX. This takes less than 50ms
-    # so the impact on the booting time is not significant.
-    wait_for_prop apexd.status ready
-    setup_runtime_bionic
-    parse_apex_configs
+    # Check any timezone data in /data is newer than the copy in the runtime module, delete if not.
+    exec - system system -- /system/bin/tzdatacheck /apex/com.android.runtime/etc/tz /data/misc/zoneinfo
 
     # If there is no post-fs-data action in the init.<device>.rc file, you
     # must uncomment this line, otherwise encrypted filesystems
diff --git a/toolbox/Android.bp b/toolbox/Android.bp
index f08cf93..7ad6f1c 100644
--- a/toolbox/Android.bp
+++ b/toolbox/Android.bp
@@ -59,6 +59,7 @@
     name: "r",
     defaults: ["toolbox_defaults"],
     srcs: ["r.c"],
+    vendor_available: true,
 }
 
 // We build BSD grep separately (but see http://b/111849261).