diff --git a/adb/socket_spec.cpp b/adb/socket_spec.cpp
index 98468b5..27e8c46 100644
--- a/adb/socket_spec.cpp
+++ b/adb/socket_spec.cpp
@@ -272,7 +272,9 @@
         if (hostname.empty() && gListenAll) {
             result = network_inaddr_any_server(port, SOCK_STREAM, error);
         } else if (tcp_host_is_local(hostname)) {
-            result = network_loopback_server(port, SOCK_STREAM, error);
+            result = network_loopback_server(port, SOCK_STREAM, error, true);
+        } else if (hostname == "::1") {
+            result = network_loopback_server(port, SOCK_STREAM, error, false);
         } else {
             // TODO: Implement me.
             *error = "listening on specified hostname currently unsupported";
diff --git a/adb/sysdeps/network.h b/adb/sysdeps/network.h
index 83ce371..fadd155 100644
--- a/adb/sysdeps/network.h
+++ b/adb/sysdeps/network.h
@@ -19,4 +19,4 @@
 #include <string>
 
 int network_loopback_client(int port, int type, std::string* error);
-int network_loopback_server(int port, int type, std::string* error);
+int network_loopback_server(int port, int type, std::string* error, bool prefer_ipv4);
diff --git a/adb/sysdeps/posix/network.cpp b/adb/sysdeps/posix/network.cpp
index c5c2275..a4d9013 100644
--- a/adb/sysdeps/posix/network.cpp
+++ b/adb/sysdeps/posix/network.cpp
@@ -119,12 +119,15 @@
     return s.release();
 }
 
-int network_loopback_server(int port, int type, std::string* error) {
-    int rc = _network_loopback_server(false, port, type, error);
+int network_loopback_server(int port, int type, std::string* error, bool prefer_ipv4) {
+    int rc = -1;
+    if (prefer_ipv4) {
+        rc = _network_loopback_server(false, port, type, error);
+    }
 
-    // Only attempt to listen on IPv6 if IPv4 is unavailable.
+    // Only attempt to listen on IPv6 if IPv4 is unavailable or prefer_ipv4 is false
     // We don't want to start an IPv6 server if there's already an IPv4 one running.
-    if (rc == -1 && (errno == EADDRNOTAVAIL || errno == EAFNOSUPPORT)) {
+    if (rc == -1 && (errno == EADDRNOTAVAIL || errno == EAFNOSUPPORT || !prefer_ipv4)) {
         return _network_loopback_server(true, port, type, error);
     }
     return rc;
diff --git a/adb/sysdeps_win32.cpp b/adb/sysdeps_win32.cpp
index 4d6cf3d..d9cc36f 100644
--- a/adb/sysdeps_win32.cpp
+++ b/adb/sysdeps_win32.cpp
@@ -920,7 +920,8 @@
     return fd;
 }
 
-int network_loopback_server(int port, int type, std::string* error) {
+int network_loopback_server(int port, int type, std::string* error, bool prefer_ipv4) {
+    // TODO implement IPv6 support on windows
     return _network_server(port, type, INADDR_LOOPBACK, error);
 }
 
@@ -1132,7 +1133,7 @@
     int local_port = -1;
     std::string error;
 
-    server = network_loopback_server(0, SOCK_STREAM, &error);
+    server = network_loopback_server(0, SOCK_STREAM, &error, true);
     if (server < 0) {
         D("adb_socketpair: failed to create server: %s", error.c_str());
         goto fail;
diff --git a/adb/test_adb.py b/adb/test_adb.py
index 8272722..3d6de26 100755
--- a/adb/test_adb.py
+++ b/adb/test_adb.py
@@ -281,6 +281,37 @@
             subprocess.check_output(["adb", "-P", str(port), "kill-server"],
                                     stderr=subprocess.STDOUT)
 
+    @unittest.skipUnless(
+        os.name == "posix",
+        "adb doesn't yet support IPv6 on Windows",
+    )
+    def test_starts_on_ipv6_localhost(self):
+        """
+        Tests that the server can start up on ::1 and that it's accessible
+        """
+        server_port = 5037
+        # Kill any existing server on this non-default port.
+        subprocess.check_output(
+            ["adb", "-P", str(server_port), "kill-server"],
+            stderr=subprocess.STDOUT,
+        )
+        try:
+            subprocess.check_output(
+                ["adb", "-L", "tcp:[::1]:{}".format(server_port), "server"],
+                stderr=subprocess.STDOUT,
+            )
+            with fake_adbd() as (port, _):
+                with adb_connect(self, serial="localhost:{}".format(port)):
+                    pass
+        finally:
+            # If we started a server, kill it.
+            subprocess.check_output(
+                ["adb", "-P", str(server_port), "kill-server"],
+                stderr=subprocess.STDOUT,
+            )
+
+
+
 
 class EmulatorTest(unittest.TestCase):
     """Tests for the emulator connection."""
diff --git a/base/Android.bp b/base/Android.bp
index 25ae535..aeb8864 100644
--- a/base/Android.bp
+++ b/base/Android.bp
@@ -58,6 +58,7 @@
         "file.cpp",
         "logging.cpp",
         "mapped_file.cpp",
+        "parsebool.cpp",
         "parsenetaddress.cpp",
         "process.cpp",
         "properties.cpp",
@@ -149,6 +150,7 @@
         "macros_test.cpp",
         "mapped_file_test.cpp",
         "parsedouble_test.cpp",
+        "parsebool_test.cpp",
         "parseint_test.cpp",
         "parsenetaddress_test.cpp",
         "process_test.cpp",
diff --git a/base/include/android-base/parsebool.h b/base/include/android-base/parsebool.h
new file mode 100644
index 0000000..b2bd021
--- /dev/null
+++ b/base/include/android-base/parsebool.h
@@ -0,0 +1,58 @@
+/*
+ * 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_view>
+
+namespace android {
+namespace base {
+
+// Parse the given string as yes or no inactivation of some sort. Return one of the
+// ParseBoolResult enumeration values.
+//
+// The following values parse as true:
+//
+//   1
+//   on
+//   true
+//   y
+//   yes
+//
+//
+// The following values parse as false:
+//
+//   0
+//   false
+//   n
+//   no
+//   off
+//
+// Anything else is a parse error.
+//
+// The purpose of this function is to have a single canonical parser for yes-or-no indications
+// throughout the system.
+
+enum class ParseBoolResult {
+  kError,
+  kFalse,
+  kTrue,
+};
+
+ParseBoolResult ParseBool(std::string_view s);
+
+}  // namespace base
+}  // namespace android
diff --git a/base/include/android-base/strings.h b/base/include/android-base/strings.h
index b1c22c9..14d534a 100644
--- a/base/include/android-base/strings.h
+++ b/base/include/android-base/strings.h
@@ -85,5 +85,10 @@
   return true;
 }
 
+// Replaces `from` with `to` in `s`, once if `all == false`, or as many times as
+// there are matches if `all == true`.
+[[nodiscard]] std::string StringReplace(std::string_view s, std::string_view from,
+                                        std::string_view to, bool all);
+
 }  // namespace base
 }  // namespace android
diff --git a/base/parsebool.cpp b/base/parsebool.cpp
new file mode 100644
index 0000000..ff96fe9
--- /dev/null
+++ b/base/parsebool.cpp
@@ -0,0 +1,34 @@
+/*
+ * 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 "android-base/parsebool.h"
+#include <errno.h>
+
+namespace android {
+namespace base {
+
+ParseBoolResult ParseBool(std::string_view s) {
+  if (s == "1" || s == "y" || s == "yes" || s == "on" || s == "true") {
+    return ParseBoolResult::kTrue;
+  }
+  if (s == "0" || s == "n" || s == "no" || s == "off" || s == "false") {
+    return ParseBoolResult::kFalse;
+  }
+  return ParseBoolResult::kError;
+}
+
+}  // namespace base
+}  // namespace android
diff --git a/base/parsebool_test.cpp b/base/parsebool_test.cpp
new file mode 100644
index 0000000..a081994
--- /dev/null
+++ b/base/parsebool_test.cpp
@@ -0,0 +1,48 @@
+/*
+ * 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 "android-base/parsebool.h"
+
+#include <errno.h>
+
+#include <gtest/gtest.h>
+#include <string_view>
+
+using android::base::ParseBool;
+using android::base::ParseBoolResult;
+
+TEST(parsebool, true_) {
+  static const char* yes[] = {
+      "1", "on", "true", "y", "yes",
+  };
+  for (const char* s : yes) {
+    ASSERT_EQ(ParseBoolResult::kTrue, ParseBool(s));
+  }
+}
+
+TEST(parsebool, false_) {
+  static const char* no[] = {
+      "0", "false", "n", "no", "off",
+  };
+  for (const char* s : no) {
+    ASSERT_EQ(ParseBoolResult::kFalse, ParseBool(s));
+  }
+}
+
+TEST(parsebool, invalid) {
+  ASSERT_EQ(ParseBoolResult::kError, ParseBool("blarg"));
+  ASSERT_EQ(ParseBoolResult::kError, ParseBool(""));
+}
diff --git a/base/properties.cpp b/base/properties.cpp
index d5a5918..4731bf2 100644
--- a/base/properties.cpp
+++ b/base/properties.cpp
@@ -28,19 +28,22 @@
 #include <map>
 #include <string>
 
+#include <android-base/parsebool.h>
 #include <android-base/parseint.h>
 
 namespace android {
 namespace base {
 
 bool GetBoolProperty(const std::string& key, bool default_value) {
-  std::string value = GetProperty(key, "");
-  if (value == "1" || value == "y" || value == "yes" || value == "on" || value == "true") {
-    return true;
-  } else if (value == "0" || value == "n" || value == "no" || value == "off" || value == "false") {
-    return false;
+  switch (ParseBool(GetProperty(key, ""))) {
+    case ParseBoolResult::kError:
+      return default_value;
+    case ParseBoolResult::kFalse:
+      return false;
+    case ParseBoolResult::kTrue:
+      return true;
   }
-  return default_value;
+  __builtin_unreachable();
 }
 
 template <typename T>
diff --git a/base/strings.cpp b/base/strings.cpp
index bb3167e..40b2bf2 100644
--- a/base/strings.cpp
+++ b/base/strings.cpp
@@ -116,5 +116,24 @@
   return lhs.size() == rhs.size() && strncasecmp(lhs.data(), rhs.data(), lhs.size()) == 0;
 }
 
+std::string StringReplace(std::string_view s, std::string_view from, std::string_view to,
+                          bool all) {
+  if (from.empty()) return std::string(s);
+
+  std::string result;
+  std::string_view::size_type start_pos = 0;
+  do {
+    std::string_view::size_type pos = s.find(from, start_pos);
+    if (pos == std::string_view::npos) break;
+
+    result.append(s.data() + start_pos, pos - start_pos);
+    result.append(to.data(), to.size());
+
+    start_pos = pos + from.size();
+  } while (all);
+  result.append(s.data() + start_pos, s.size() - start_pos);
+  return result;
+}
+
 }  // namespace base
 }  // namespace android
diff --git a/base/strings_test.cpp b/base/strings_test.cpp
index ca3c0b8..5ae3094 100644
--- a/base/strings_test.cpp
+++ b/base/strings_test.cpp
@@ -311,3 +311,46 @@
   ASSERT_TRUE(android::base::ConsumeSuffix(&s, ".bar"));
   ASSERT_EQ("foo", s);
 }
+
+TEST(strings, StringReplace_false) {
+  // No change.
+  ASSERT_EQ("abcabc", android::base::StringReplace("abcabc", "z", "Z", false));
+  ASSERT_EQ("", android::base::StringReplace("", "z", "Z", false));
+  ASSERT_EQ("abcabc", android::base::StringReplace("abcabc", "", "Z", false));
+
+  // Equal lengths.
+  ASSERT_EQ("Abcabc", android::base::StringReplace("abcabc", "a", "A", false));
+  ASSERT_EQ("aBcabc", android::base::StringReplace("abcabc", "b", "B", false));
+  ASSERT_EQ("abCabc", android::base::StringReplace("abcabc", "c", "C", false));
+
+  // Longer replacement.
+  ASSERT_EQ("foobcabc", android::base::StringReplace("abcabc", "a", "foo", false));
+  ASSERT_EQ("afoocabc", android::base::StringReplace("abcabc", "b", "foo", false));
+  ASSERT_EQ("abfooabc", android::base::StringReplace("abcabc", "c", "foo", false));
+
+  // Shorter replacement.
+  ASSERT_EQ("xxyz", android::base::StringReplace("abcxyz", "abc", "x", false));
+  ASSERT_EQ("axyz", android::base::StringReplace("abcxyz", "bcx", "x", false));
+  ASSERT_EQ("abcx", android::base::StringReplace("abcxyz", "xyz", "x", false));
+}
+
+TEST(strings, StringReplace_true) {
+  // No change.
+  ASSERT_EQ("abcabc", android::base::StringReplace("abcabc", "z", "Z", true));
+  ASSERT_EQ("", android::base::StringReplace("", "z", "Z", true));
+  ASSERT_EQ("abcabc", android::base::StringReplace("abcabc", "", "Z", true));
+
+  // Equal lengths.
+  ASSERT_EQ("AbcAbc", android::base::StringReplace("abcabc", "a", "A", true));
+  ASSERT_EQ("aBcaBc", android::base::StringReplace("abcabc", "b", "B", true));
+  ASSERT_EQ("abCabC", android::base::StringReplace("abcabc", "c", "C", true));
+
+  // Longer replacement.
+  ASSERT_EQ("foobcfoobc", android::base::StringReplace("abcabc", "a", "foo", true));
+  ASSERT_EQ("afoocafooc", android::base::StringReplace("abcabc", "b", "foo", true));
+  ASSERT_EQ("abfooabfoo", android::base::StringReplace("abcabc", "c", "foo", true));
+
+  // Shorter replacement.
+  ASSERT_EQ("xxyzx", android::base::StringReplace("abcxyzabc", "abc", "x", true));
+  ASSERT_EQ("<xx>", android::base::StringReplace("<abcabc>", "abc", "x", true));
+}
diff --git a/debuggerd/libdebuggerd/include/libdebuggerd/utility.h b/debuggerd/libdebuggerd/include/libdebuggerd/utility.h
index f189c45..75bac87 100644
--- a/debuggerd/libdebuggerd/include/libdebuggerd/utility.h
+++ b/debuggerd/libdebuggerd/include/libdebuggerd/utility.h
@@ -20,6 +20,7 @@
 
 #include <inttypes.h>
 #include <signal.h>
+#include <stdarg.h>
 #include <stdbool.h>
 #include <sys/types.h>
 
@@ -71,6 +72,7 @@
 
 // Log information onto the tombstone.
 void _LOG(log_t* log, logtype ltype, const char* fmt, ...) __attribute__((format(printf, 3, 4)));
+void _VLOG(log_t* log, logtype ltype, const char* fmt, va_list ap);
 
 namespace unwindstack {
 class Unwinder;
diff --git a/debuggerd/libdebuggerd/tombstone.cpp b/debuggerd/libdebuggerd/tombstone.cpp
index 1993840..236fcf7 100644
--- a/debuggerd/libdebuggerd/tombstone.cpp
+++ b/debuggerd/libdebuggerd/tombstone.cpp
@@ -428,7 +428,7 @@
   std::vector<std::pair<std::string, uint64_t>> special_row;
 
 #if defined(__arm__) || defined(__aarch64__)
-  static constexpr const char* special_registers[] = {"ip", "lr", "sp", "pc"};
+  static constexpr const char* special_registers[] = {"ip", "lr", "sp", "pc", "pst"};
 #elif defined(__i386__)
   static constexpr const char* special_registers[] = {"ebp", "esp", "eip"};
 #elif defined(__x86_64__)
diff --git a/debuggerd/libdebuggerd/utility.cpp b/debuggerd/libdebuggerd/utility.cpp
index 9b2779a..5ce26fc 100644
--- a/debuggerd/libdebuggerd/utility.cpp
+++ b/debuggerd/libdebuggerd/utility.cpp
@@ -67,6 +67,14 @@
 
 __attribute__((__weak__, visibility("default")))
 void _LOG(log_t* log, enum logtype ltype, const char* fmt, ...) {
+  va_list ap;
+  va_start(ap, fmt);
+  _VLOG(log, ltype, fmt, ap);
+  va_end(ap);
+}
+
+__attribute__((__weak__, visibility("default")))
+void _VLOG(log_t* log, enum logtype ltype, const char* fmt, va_list ap) {
   bool write_to_tombstone = (log->tfd != -1);
   bool write_to_logcat = is_allowed_in_logcat(ltype)
                       && log->crashed_tid != -1
@@ -75,10 +83,7 @@
   static bool write_to_kmsg = should_write_to_kmsg();
 
   std::string msg;
-  va_list ap;
-  va_start(ap, fmt);
   android::base::StringAppendV(&msg, fmt, ap);
-  va_end(ap);
 
   if (msg.empty()) return;
 
diff --git a/fastboot/Android.bp b/fastboot/Android.bp
index 02a887e..a757d56 100644
--- a/fastboot/Android.bp
+++ b/fastboot/Android.bp
@@ -137,12 +137,14 @@
         "libhidlbase",
         "liblog",
         "liblp",
+        "libprotobuf-cpp-lite",
         "libsparse",
         "libutils",
     ],
 
     static_libs: [
         "libhealthhalutils",
+        "libsnapshot_nobinder",
     ],
 
     header_libs: [
diff --git a/fastboot/device/commands.cpp b/fastboot/device/commands.cpp
index a2c95d6..1a745ab 100644
--- a/fastboot/device/commands.cpp
+++ b/fastboot/device/commands.cpp
@@ -19,6 +19,8 @@
 #include <sys/socket.h>
 #include <sys/un.h>
 
+#include <unordered_set>
+
 #include <android-base/logging.h>
 #include <android-base/parseint.h>
 #include <android-base/properties.h>
@@ -33,6 +35,7 @@
 #include <libgsi/libgsi.h>
 #include <liblp/builder.h>
 #include <liblp/liblp.h>
+#include <libsnapshot/snapshot.h>
 #include <uuid/uuid.h>
 
 #include "constants.h"
@@ -48,6 +51,7 @@
 using ::android::hardware::boot::V1_1::MergeStatus;
 using ::android::hardware::fastboot::V1_0::Result;
 using ::android::hardware::fastboot::V1_0::Status;
+using android::snapshot::SnapshotManager;
 using IBootControl1_1 = ::android::hardware::boot::V1_1::IBootControl;
 
 struct VariableHandlers {
@@ -57,6 +61,24 @@
     std::function<std::vector<std::vector<std::string>>(FastbootDevice*)> get_all_args;
 };
 
+static bool IsSnapshotUpdateInProgress(FastbootDevice* device) {
+    auto hal = device->boot1_1();
+    if (!hal) {
+        return false;
+    }
+    auto merge_status = hal->getSnapshotMergeStatus();
+    return merge_status == MergeStatus::SNAPSHOTTED || merge_status == MergeStatus::MERGING;
+}
+
+static bool IsProtectedPartitionDuringMerge(FastbootDevice* device, const std::string& name) {
+    static const std::unordered_set<std::string> ProtectedPartitionsDuringMerge = {
+            "userdata", "metadata", "misc"};
+    if (ProtectedPartitionsDuringMerge.count(name) == 0) {
+        return false;
+    }
+    return IsSnapshotUpdateInProgress(device);
+}
+
 static void GetAllVars(FastbootDevice* device, const std::string& name,
                        const VariableHandlers& handlers) {
     if (!handlers.get_all_args) {
@@ -143,8 +165,14 @@
         return device->WriteStatus(FastbootResult::FAIL, "Erase is not allowed on locked devices");
     }
 
+    const auto& partition_name = args[1];
+    if (IsProtectedPartitionDuringMerge(device, partition_name)) {
+        auto message = "Cannot erase " + partition_name + " while a snapshot update is in progress";
+        return device->WriteFail(message);
+    }
+
     PartitionHandle handle;
-    if (!OpenPartition(device, args[1], &handle)) {
+    if (!OpenPartition(device, partition_name, &handle)) {
         return device->WriteStatus(FastbootResult::FAIL, "Partition doesn't exist");
     }
     if (wipe_block_device(handle.fd(), get_block_device_size(handle.fd())) == 0) {
@@ -209,9 +237,9 @@
                                    "set_active command is not allowed on locked devices");
     }
 
-    // Slot suffix needs to be between 'a' and 'z'.
     Slot slot;
     if (!GetSlotNumber(args[1], &slot)) {
+        // Slot suffix needs to be between 'a' and 'z'.
         return device->WriteStatus(FastbootResult::FAIL, "Bad slot suffix");
     }
 
@@ -224,6 +252,32 @@
     if (slot >= boot_control_hal->getNumberSlots()) {
         return device->WriteStatus(FastbootResult::FAIL, "Slot out of range");
     }
+
+    // If the slot is not changing, do nothing.
+    if (slot == boot_control_hal->getCurrentSlot()) {
+        return device->WriteOkay("");
+    }
+
+    // Check how to handle the current snapshot state.
+    if (auto hal11 = device->boot1_1()) {
+        auto merge_status = hal11->getSnapshotMergeStatus();
+        if (merge_status == MergeStatus::MERGING) {
+            return device->WriteFail("Cannot change slots while a snapshot update is in progress");
+        }
+        // Note: we allow the slot change if the state is SNAPSHOTTED. First-
+        // stage init does not have access to the HAL, and uses the slot number
+        // and /metadata OTA state to determine whether a slot change occurred.
+        // Booting into the old slot would erase the OTA, and switching A->B->A
+        // would simply resume it if no boots occur in between. Re-flashing
+        // partitions implicitly cancels the OTA, so leaving the state as-is is
+        // safe.
+        if (merge_status == MergeStatus::SNAPSHOTTED) {
+            device->WriteInfo(
+                    "Changing the active slot with a snapshot applied may cancel the"
+                    " update.");
+        }
+    }
+
     CommandResult ret;
     auto cb = [&ret](CommandResult result) { ret = result; };
     auto result = boot_control_hal->setActiveBootSlot(slot, cb);
@@ -467,6 +521,11 @@
     }
 
     const auto& partition_name = args[1];
+    if (IsProtectedPartitionDuringMerge(device, partition_name)) {
+        auto message = "Cannot flash " + partition_name + " while a snapshot update is in progress";
+        return device->WriteFail(message);
+    }
+
     if (LogicalPartitionExists(device, partition_name)) {
         CancelPartitionSnapshot(device, partition_name);
     }
@@ -556,12 +615,9 @@
 bool SnapshotUpdateHandler(FastbootDevice* device, const std::vector<std::string>& args) {
     // Note that we use the HAL rather than mounting /metadata, since we want
     // our results to match the bootloader.
-    auto hal = device->boot_control_hal();
+    auto hal = device->boot1_1();
     if (!hal) return device->WriteFail("Not supported");
 
-    android::sp<IBootControl1_1> hal11 = IBootControl1_1::castFrom(hal);
-    if (!hal11) return device->WriteFail("Not supported");
-
     // If no arguments, return the same thing as a getvar. Note that we get the
     // HAL first so we can return "not supported" before we return the less
     // specific error message below.
@@ -574,18 +630,34 @@
         return device->WriteOkay("");
     }
 
-    if (args.size() != 2 || args[1] != "cancel") {
+    MergeStatus status = hal->getSnapshotMergeStatus();
+
+    if (args.size() != 2) {
         return device->WriteFail("Invalid arguments");
     }
+    if (args[1] == "cancel") {
+        switch (status) {
+            case MergeStatus::SNAPSHOTTED:
+            case MergeStatus::MERGING:
+                hal->setSnapshotMergeStatus(MergeStatus::CANCELLED);
+                break;
+            default:
+                break;
+        }
+    } else if (args[1] == "merge") {
+        if (status != MergeStatus::MERGING) {
+            return device->WriteFail("No snapshot merge is in progress");
+        }
 
-    MergeStatus status = hal11->getSnapshotMergeStatus();
-    switch (status) {
-        case MergeStatus::SNAPSHOTTED:
-        case MergeStatus::MERGING:
-            hal11->setSnapshotMergeStatus(MergeStatus::CANCELLED);
-            break;
-        default:
-            break;
+        auto sm = SnapshotManager::NewForFirstStageMount();
+        if (!sm) {
+            return device->WriteFail("Unable to create SnapshotManager");
+        }
+        if (!sm->HandleImminentDataWipe()) {
+            return device->WriteFail("Unable to finish snapshot merge");
+        }
+    } else {
+        return device->WriteFail("Invalid parameter to snapshot-update");
     }
     return device->WriteStatus(FastbootResult::OKAY, "Success");
 }
diff --git a/fastboot/device/fastboot_device.cpp b/fastboot/device/fastboot_device.cpp
index d3c2bda..31fc359 100644
--- a/fastboot/device/fastboot_device.cpp
+++ b/fastboot/device/fastboot_device.cpp
@@ -60,7 +60,11 @@
       boot_control_hal_(IBootControl::getService()),
       health_hal_(get_health_service()),
       fastboot_hal_(IFastboot::getService()),
-      active_slot_("") {}
+      active_slot_("") {
+    if (boot_control_hal_) {
+        boot1_1_ = android::hardware::boot::V1_1::IBootControl::castFrom(boot_control_hal_);
+    }
+}
 
 FastbootDevice::~FastbootDevice() {
     CloseDevice();
diff --git a/fastboot/device/fastboot_device.h b/fastboot/device/fastboot_device.h
index 091aadf..bbe8172 100644
--- a/fastboot/device/fastboot_device.h
+++ b/fastboot/device/fastboot_device.h
@@ -23,6 +23,7 @@
 #include <vector>
 
 #include <android/hardware/boot/1.0/IBootControl.h>
+#include <android/hardware/boot/1.1/IBootControl.h>
 #include <android/hardware/fastboot/1.0/IFastboot.h>
 #include <android/hardware/health/2.0/IHealth.h>
 
@@ -51,6 +52,7 @@
     android::sp<android::hardware::boot::V1_0::IBootControl> boot_control_hal() {
         return boot_control_hal_;
     }
+    android::sp<android::hardware::boot::V1_1::IBootControl> boot1_1() { return boot1_1_; }
     android::sp<android::hardware::fastboot::V1_0::IFastboot> fastboot_hal() {
         return fastboot_hal_;
     }
@@ -63,6 +65,7 @@
 
     std::unique_ptr<Transport> transport_;
     android::sp<android::hardware::boot::V1_0::IBootControl> boot_control_hal_;
+    android::sp<android::hardware::boot::V1_1::IBootControl> boot1_1_;
     android::sp<android::hardware::health::V2_0::IHealth> health_hal_;
     android::sp<android::hardware::fastboot::V1_0::IFastboot> fastboot_hal_;
     std::vector<char> download_data_;
diff --git a/fastboot/device/variables.cpp b/fastboot/device/variables.cpp
index 717db06..10eac01 100644
--- a/fastboot/device/variables.cpp
+++ b/fastboot/device/variables.cpp
@@ -432,19 +432,13 @@
                              std::string* message) {
     // Note that we use the HAL rather than mounting /metadata, since we want
     // our results to match the bootloader.
-    auto hal = device->boot_control_hal();
+    auto hal = device->boot1_1();
     if (!hal) {
         *message = "not supported";
         return false;
     }
 
-    android::sp<IBootControl1_1> hal11 = IBootControl1_1::castFrom(hal);
-    if (!hal11) {
-        *message = "not supported";
-        return false;
-    }
-
-    MergeStatus status = hal11->getSnapshotMergeStatus();
+    MergeStatus status = hal->getSnapshotMergeStatus();
     switch (status) {
         case MergeStatus::SNAPSHOTTED:
             *message = "snapshotted";
diff --git a/fastboot/fastboot.cpp b/fastboot/fastboot.cpp
index 7ce7c7c..cbd42b1 100644
--- a/fastboot/fastboot.cpp
+++ b/fastboot/fastboot.cpp
@@ -399,6 +399,9 @@
             " snapshot-update cancel     On devices that support snapshot-based updates, cancel\n"
             "                            an in-progress update. This may make the device\n"
             "                            unbootable until it is reflashed.\n"
+            " snapshot-update merge      On devices that support snapshot-based updates, finish\n"
+            "                            an in-progress update if it is in the \"merging\"\n"
+            "                            phase.\n"
             "\n"
             "boot image:\n"
             " boot KERNEL [RAMDISK [SECOND]]\n"
@@ -2089,8 +2092,8 @@
             if (!args.empty()) {
                 arg = next_arg(&args);
             }
-            if (!arg.empty() && arg != "cancel") {
-                syntax_error("expected: snapshot-update [cancel]");
+            if (!arg.empty() && (arg != "cancel" && arg != "merge")) {
+                syntax_error("expected: snapshot-update [cancel|merge]");
             }
             fb->SnapshotUpdateCommand(arg);
         } else {
diff --git a/fastboot/fastboot_driver.cpp b/fastboot/fastboot_driver.cpp
index 6a5ad20..8d534ea 100644
--- a/fastboot/fastboot_driver.cpp
+++ b/fastboot/fastboot_driver.cpp
@@ -124,8 +124,11 @@
 
 RetCode FastBootDriver::SnapshotUpdateCommand(const std::string& command, std::string* response,
                                               std::vector<std::string>* info) {
+    prolog_(StringPrintf("Snapshot %s", command.c_str()));
     std::string raw = FB_CMD_SNAPSHOT_UPDATE ":" + command;
-    return RawCommand(raw, response, info);
+    auto result = RawCommand(raw, response, info);
+    epilog_(result);
+    return result;
 }
 
 RetCode FastBootDriver::FlashPartition(const std::string& partition,
diff --git a/fs_mgr/fs_mgr.cpp b/fs_mgr/fs_mgr.cpp
index 75ebd94..cb69037 100644
--- a/fs_mgr/fs_mgr.cpp
+++ b/fs_mgr/fs_mgr.cpp
@@ -1351,38 +1351,9 @@
     return ret;
 }
 
-static std::string GetUserdataBlockDevice() {
-    Fstab fstab;
-    if (!ReadFstabFromFile("/proc/mounts", &fstab)) {
-        LERROR << "Failed to read /proc/mounts";
-        return "";
-    }
-    auto entry = GetEntryForMountPoint(&fstab, "/data");
-    if (entry == nullptr) {
-        LERROR << "Didn't find /data mount point in /proc/mounts";
-        return "";
-    }
-    return entry->blk_device;
-}
-
 int fs_mgr_remount_userdata_into_checkpointing(Fstab* fstab) {
-    const std::string& block_device = GetUserdataBlockDevice();
-    LINFO << "Userdata is mounted on " << block_device;
-    auto entry = std::find_if(fstab->begin(), fstab->end(), [&block_device](const FstabEntry& e) {
-        if (e.mount_point != "/data") {
-            return false;
-        }
-        if (e.blk_device == block_device) {
-            return true;
-        }
-        DeviceMapper& dm = DeviceMapper::Instance();
-        std::string path;
-        if (!dm.GetDmDevicePathByName("userdata", &path)) {
-            return false;
-        }
-        return path == block_device;
-    });
-    if (entry == fstab->end()) {
+    auto entry = GetMountedEntryForUserdata(fstab);
+    if (entry == nullptr) {
         LERROR << "Can't find /data in fstab";
         return -1;
     }
diff --git a/fs_mgr/fs_mgr_fstab.cpp b/fs_mgr/fs_mgr_fstab.cpp
index d216458..c81a079 100644
--- a/fs_mgr/fs_mgr_fstab.cpp
+++ b/fs_mgr/fs_mgr_fstab.cpp
@@ -40,6 +40,7 @@
 using android::base::ParseByteCount;
 using android::base::ParseInt;
 using android::base::ReadFileToString;
+using android::base::Readlink;
 using android::base::Split;
 using android::base::StartsWith;
 
@@ -809,6 +810,89 @@
     return entries;
 }
 
+static std::string ResolveBlockDevice(const std::string& block_device) {
+    if (!StartsWith(block_device, "/dev/block/")) {
+        LWARNING << block_device << " is not a block device";
+        return block_device;
+    }
+    std::string name = block_device.substr(5);
+    if (!StartsWith(name, "block/dm-")) {
+        // Not a dm-device, but might be a symlink. Optimistically try to readlink.
+        std::string result;
+        if (Readlink(block_device, &result)) {
+            return result;
+        } else if (errno == EINVAL) {
+            // After all, it wasn't a symlink.
+            return block_device;
+        } else {
+            LERROR << "Failed to readlink " << block_device;
+            return "";
+        }
+    }
+    // It's a dm-device, let's find what's inside!
+    std::string sys_dir = "/sys/" + name;
+    while (true) {
+        std::string slaves_dir = sys_dir + "/slaves";
+        std::unique_ptr<DIR, decltype(&closedir)> dir(opendir(slaves_dir.c_str()), closedir);
+        if (!dir) {
+            LERROR << "Failed to open " << slaves_dir;
+            return "";
+        }
+        std::string sub_device_name = "";
+        for (auto entry = readdir(dir.get()); entry; entry = readdir(dir.get())) {
+            if (entry->d_type != DT_LNK) continue;
+            if (!sub_device_name.empty()) {
+                LERROR << "Too many slaves in " << slaves_dir;
+                return "";
+            }
+            sub_device_name = entry->d_name;
+        }
+        if (sub_device_name.empty()) {
+            LERROR << "No slaves in " << slaves_dir;
+            return "";
+        }
+        if (!StartsWith(sub_device_name, "dm-")) {
+            // Not a dm-device! We can stop now.
+            return "/dev/block/" + sub_device_name;
+        }
+        // Still a dm-device, keep digging.
+        sys_dir = "/sys/block/" + sub_device_name;
+    }
+}
+
+FstabEntry* GetMountedEntryForUserdata(Fstab* fstab) {
+    Fstab mounts;
+    if (!ReadFstabFromFile("/proc/mounts", &mounts)) {
+        LERROR << "Failed to read /proc/mounts";
+        return nullptr;
+    }
+    auto mounted_entry = GetEntryForMountPoint(&mounts, "/data");
+    if (mounted_entry == nullptr) {
+        LWARNING << "/data is not mounted";
+        return nullptr;
+    }
+    std::string resolved_block_device = ResolveBlockDevice(mounted_entry->blk_device);
+    if (resolved_block_device.empty()) {
+        return nullptr;
+    }
+    LINFO << "/data is mounted on " << resolved_block_device;
+    for (auto& entry : *fstab) {
+        if (entry.mount_point != "/data") {
+            continue;
+        }
+        std::string block_device;
+        if (!Readlink(entry.blk_device, &block_device)) {
+            LWARNING << "Failed to readlink " << entry.blk_device;
+            block_device = entry.blk_device;
+        }
+        if (block_device == resolved_block_device) {
+            return &entry;
+        }
+    }
+    LERROR << "Didn't find entry that was used to mount /data";
+    return nullptr;
+}
+
 std::set<std::string> GetBootDevices() {
     // First check the kernel commandline, then try the device tree otherwise
     std::string dt_file_name = get_android_dt_dir() + "/boot_devices";
diff --git a/fs_mgr/include_fstab/fstab/fstab.h b/fs_mgr/include_fstab/fstab/fstab.h
index c6a16e3..80deaef 100644
--- a/fs_mgr/include_fstab/fstab/fstab.h
+++ b/fs_mgr/include_fstab/fstab/fstab.h
@@ -102,6 +102,7 @@
 FstabEntry* GetEntryForMountPoint(Fstab* fstab, const std::string& path);
 // The Fstab can contain multiple entries for the same mount point with different configurations.
 std::vector<FstabEntry*> GetEntriesForMountPoint(Fstab* fstab, const std::string& path);
+FstabEntry* GetMountedEntryForUserdata(Fstab* fstab);
 
 // This method builds DSU fstab entries and transfer the fstab.
 //
diff --git a/fs_mgr/liblp/images.cpp b/fs_mgr/liblp/images.cpp
index 6b842b3..e4d92ca 100644
--- a/fs_mgr/liblp/images.cpp
+++ b/fs_mgr/liblp/images.cpp
@@ -110,7 +110,7 @@
     return ReadFromImageFile(fd);
 }
 
-bool WriteToImageFile(int fd, const LpMetadata& input) {
+bool WriteToImageFile(borrowed_fd fd, const LpMetadata& input) {
     std::string geometry = SerializeGeometry(input.geometry);
     std::string metadata = SerializeMetadata(input);
 
diff --git a/fs_mgr/liblp/images.h b/fs_mgr/liblp/images.h
index a284d2e..88e5882 100644
--- a/fs_mgr/liblp/images.h
+++ b/fs_mgr/liblp/images.h
@@ -29,8 +29,6 @@
 // Helper function to serialize geometry and metadata to a normal file, for
 // flashing or debugging.
 std::unique_ptr<LpMetadata> ReadFromImageFile(int fd);
-bool WriteToImageFile(const char* file, const LpMetadata& metadata);
-bool WriteToImageFile(int fd, const LpMetadata& metadata);
 
 // We use an object to build the image file since it requires that data
 // pointers be held alive until the sparse file is destroyed. It's easier
diff --git a/fs_mgr/liblp/include/liblp/liblp.h b/fs_mgr/liblp/include/liblp/liblp.h
index cd860cd..04f8987 100644
--- a/fs_mgr/liblp/include/liblp/liblp.h
+++ b/fs_mgr/liblp/include/liblp/liblp.h
@@ -76,12 +76,15 @@
 // supported). It is a format specifically for storing only metadata.
 bool IsEmptySuperImage(const std::string& file);
 
-// Read/Write logical partition metadata to an image file, for diagnostics or
-// flashing. If no partition images are specified, the file will be in the
-// empty format.
+// Read/Write logical partition metadata and contents to an image file, for
+// flashing.
 bool WriteToImageFile(const std::string& file, const LpMetadata& metadata, uint32_t block_size,
                       const std::map<std::string, std::string>& images, bool sparsify);
+
+// Read/Write logical partition metadata to an image file, for producing a
+// super_empty.img (for fastboot wipe-super/update-super) or for diagnostics.
 bool WriteToImageFile(const std::string& file, const LpMetadata& metadata);
+bool WriteToImageFile(android::base::borrowed_fd fd, const LpMetadata& metadata);
 std::unique_ptr<LpMetadata> ReadFromImageFile(const std::string& image_file);
 std::unique_ptr<LpMetadata> ReadFromImageBlob(const void* data, size_t bytes);
 
diff --git a/fs_mgr/liblp/writer.cpp b/fs_mgr/liblp/writer.cpp
index 8a983ad..bb24069 100644
--- a/fs_mgr/liblp/writer.cpp
+++ b/fs_mgr/liblp/writer.cpp
@@ -83,8 +83,9 @@
 
 // Perform sanity checks so we don't accidentally overwrite valid metadata
 // with potentially invalid metadata, or random partition data with metadata.
-static bool ValidateAndSerializeMetadata(const IPartitionOpener& opener, const LpMetadata& metadata,
-                                         const std::string& slot_suffix, std::string* blob) {
+static bool ValidateAndSerializeMetadata([[maybe_unused]] const IPartitionOpener& opener,
+                                         const LpMetadata& metadata, const std::string& slot_suffix,
+                                         std::string* blob) {
     const LpMetadataGeometry& geometry = metadata.geometry;
 
     *blob = SerializeMetadata(metadata);
@@ -128,6 +129,10 @@
                    << block_device.first_logical_sector << " for size " << block_device.size;
             return false;
         }
+
+        // When flashing on the device, check partition sizes. Don't do this on
+        // the host since there is no way to verify.
+#if defined(__ANDROID__)
         BlockDeviceInfo info;
         if (!opener.GetInfo(partition_name, &info)) {
             PERROR << partition_name << ": ioctl";
@@ -138,6 +143,7 @@
                    << block_device.size << ", got " << info.size << ")";
             return false;
         }
+#endif
     }
 
     // Make sure all partition entries reference valid extents.
diff --git a/fs_mgr/libsnapshot/include/libsnapshot/snapshot.h b/fs_mgr/libsnapshot/include/libsnapshot/snapshot.h
index 8f24709..7411e5a 100644
--- a/fs_mgr/libsnapshot/include/libsnapshot/snapshot.h
+++ b/fs_mgr/libsnapshot/include/libsnapshot/snapshot.h
@@ -224,7 +224,8 @@
     bool CreateLogicalAndSnapshotPartitions(const std::string& super_device);
 
     // This method should be called preceding any wipe or flash of metadata or
-    // userdata. It is only valid in recovery.
+    // userdata. It is only valid in recovery or fastbootd, and it ensures that
+    // a merge has been completed.
     //
     // When userdata will be wiped or flashed, it is necessary to clean up any
     // snapshot state. If a merge is in progress, the merge must be finished.
diff --git a/fs_mgr/libsnapshot/snapshot.cpp b/fs_mgr/libsnapshot/snapshot.cpp
index d1b1cb4..50d04b1 100644
--- a/fs_mgr/libsnapshot/snapshot.cpp
+++ b/fs_mgr/libsnapshot/snapshot.cpp
@@ -2204,6 +2204,15 @@
         return true;
     }
 
+    // Check this early, so we don't accidentally start trying to populate
+    // the state file in recovery. Note we don't call GetUpdateState since
+    // we want errors in acquiring the lock to be propagated, instead of
+    // returning UpdateState::None.
+    auto state_file = GetStateFilePath();
+    if (access(state_file.c_str(), F_OK) != 0 && errno == ENOENT) {
+        return true;
+    }
+
     auto slot_number = SlotNumberForSlotSuffix(device_->GetSlotSuffix());
     auto super_path = device_->GetSuperDevice(slot_number);
     if (!CreateLogicalAndSnapshotPartitions(super_path)) {
diff --git a/fs_mgr/tests/fs_mgr_test.cpp b/fs_mgr/tests/fs_mgr_test.cpp
index 1cbaf45..c5adea6 100644
--- a/fs_mgr/tests/fs_mgr_test.cpp
+++ b/fs_mgr/tests/fs_mgr_test.cpp
@@ -969,3 +969,14 @@
     ASSERT_NE(nullptr, GetEntryForMountPoint(&fstab, "/data"))
             << "Default fstab doesn't contain /data entry";
 }
+
+TEST(fs_mgr, UserdataMountedFromDefaultFstab) {
+    if (getuid() != 0) {
+        GTEST_SKIP() << "Must be run as root.";
+        return;
+    }
+    Fstab fstab;
+    ASSERT_TRUE(ReadDefaultFstab(&fstab)) << "Failed to read default fstab";
+    ASSERT_NE(nullptr, GetMountedEntryForUserdata(&fstab))
+            << "/data wasn't mounted from default fstab";
+}
diff --git a/init/Android.bp b/init/Android.bp
index c7021c3..9529617 100644
--- a/init/Android.bp
+++ b/init/Android.bp
@@ -152,6 +152,7 @@
     whole_static_libs: [
         "libcap",
         "com.android.sysprop.apex",
+        "com.android.sysprop.init",
     ],
     header_libs: ["bootimg_headers"],
     proto: {
diff --git a/init/builtins.cpp b/init/builtins.cpp
index 8f58145..485806b 100644
--- a/init/builtins.cpp
+++ b/init/builtins.cpp
@@ -45,6 +45,7 @@
 #include <memory>
 
 #include <ApexProperties.sysprop.h>
+#include <InitProperties.sysprop.h>
 #include <android-base/chrono_utils.h>
 #include <android-base/file.h>
 #include <android-base/logging.h>
@@ -1222,7 +1223,9 @@
     boot_clock::time_point now = boot_clock::now();
     property_set("sys.init.userspace_reboot.last_finished",
                  std::to_string(now.time_since_epoch().count()));
-    property_set(kUserspaceRebootInProgress, "0");
+    if (!android::sysprop::InitProperties::userspace_reboot_in_progress(false)) {
+        return Error() << "Failed to set sys.init.userspace_reboot.in_progress property";
+    }
     return {};
 }
 
diff --git a/init/reboot.cpp b/init/reboot.cpp
index 7040f26..13cebcc 100644
--- a/init/reboot.cpp
+++ b/init/reboot.cpp
@@ -38,6 +38,7 @@
 #include <thread>
 #include <vector>
 
+#include <InitProperties.sysprop.h>
 #include <android-base/chrono_utils.h>
 #include <android-base/file.h>
 #include <android-base/logging.h>
@@ -743,8 +744,8 @@
     // actions. We should make sure, that all of them are propagated before
     // proceeding with userspace reboot. Synchronously setting kUserspaceRebootInProgress property
     // is not perfect, but it should do the trick.
-    if (property_set(kUserspaceRebootInProgress, "1") != 0) {
-        return Error() << "Failed to set property " << kUserspaceRebootInProgress;
+    if (!android::sysprop::InitProperties::userspace_reboot_in_progress(true)) {
+        return Error() << "Failed to set sys.init.userspace_reboot.in_progress property";
     }
     EnterShutdown();
     std::vector<Service*> stop_first;
@@ -760,6 +761,12 @@
             were_enabled.push_back(s);
         }
     }
+    {
+        Timer sync_timer;
+        LOG(INFO) << "sync() before terminating services...";
+        sync();
+        LOG(INFO) << "sync() took " << sync_timer;
+    }
     // TODO(b/135984674): do we need shutdown animation for userspace reboot?
     // TODO(b/135984674): control userspace timeout via read-only property?
     StopServicesAndLogViolations(stop_first, 10s, true /* SIGTERM */);
@@ -775,6 +782,12 @@
         // TODO(b/135984674): store information about offending services for debugging.
         return Error() << r << " debugging services are still running";
     }
+    {
+        Timer sync_timer;
+        LOG(INFO) << "sync() after stopping services...";
+        sync();
+        LOG(INFO) << "sync() took " << sync_timer;
+    }
     if (auto result = UnmountAllApexes(); !result) {
         return result;
     }
@@ -792,7 +805,38 @@
     return {};
 }
 
+static void UserspaceRebootWatchdogThread() {
+    if (!WaitForProperty("sys.init.userspace_reboot_in_progress", "1", 20s)) {
+        // TODO(b/135984674): should we reboot instead?
+        LOG(WARNING) << "Userspace reboot didn't start in 20 seconds. Stopping watchdog";
+        return;
+    }
+    LOG(INFO) << "Starting userspace reboot watchdog";
+    // TODO(b/135984674): this should be configured via a read-only sysprop.
+    std::chrono::milliseconds timeout = 60s;
+    if (!WaitForProperty("sys.boot_completed", "1", timeout)) {
+        LOG(ERROR) << "Failed to boot in " << timeout.count() << "ms. Switching to full reboot";
+        // In this case device is in a boot loop. Only way to recover is to do dirty reboot.
+        RebootSystem(ANDROID_RB_RESTART2, "userspace-reboot-watchdog-triggered");
+    }
+    LOG(INFO) << "Device booted, stopping userspace reboot watchdog";
+}
+
 static void HandleUserspaceReboot() {
+    // Spinnig up a separate thread will fail the setns call later in the boot sequence.
+    // Fork a new process to monitor userspace reboot while we are investigating a better solution.
+    pid_t pid = fork();
+    if (pid < 0) {
+        PLOG(ERROR) << "Failed to fork process for userspace reboot watchdog. Switching to full "
+                    << "reboot";
+        trigger_shutdown("reboot,userspace-reboot-failed-to-fork");
+        return;
+    }
+    if (pid == 0) {
+        // Child
+        UserspaceRebootWatchdogThread();
+        _exit(EXIT_SUCCESS);
+    }
     LOG(INFO) << "Clearing queue and starting userspace-reboot-requested trigger";
     auto& am = ActionManager::GetInstance();
     am.ClearQueue();
diff --git a/init/reboot.h b/init/reboot.h
index cdfa024..81c3edc 100644
--- a/init/reboot.h
+++ b/init/reboot.h
@@ -22,8 +22,6 @@
 namespace android {
 namespace init {
 
-static const constexpr char* kUserspaceRebootInProgress = "sys.init.userspace_reboot.in_progress";
-
 // Parses and handles a setprop sys.powerctl message.
 void HandlePowerctlMessage(const std::string& command);
 
diff --git a/init/subcontext.cpp b/init/subcontext.cpp
index e55265b..bebcc77 100644
--- a/init/subcontext.cpp
+++ b/init/subcontext.cpp
@@ -209,8 +209,12 @@
             PLOG(FATAL) << "Could not dup child_fd";
         }
 
-        if (setexeccon(context_.c_str()) < 0) {
-            PLOG(FATAL) << "Could not set execcon for '" << context_ << "'";
+        // We don't switch contexts if we're running the unit tests.  We don't use std::optional,
+        // since we still need a real context string to pass to the builtin functions.
+        if (context_ != kTestContext) {
+            if (setexeccon(context_.c_str()) < 0) {
+                PLOG(FATAL) << "Could not set execcon for '" << context_ << "'";
+            }
         }
 
         auto init_path = GetExecutablePath();
diff --git a/init/subcontext.h b/init/subcontext.h
index bcaad29..5e1d8a8 100644
--- a/init/subcontext.h
+++ b/init/subcontext.h
@@ -32,6 +32,7 @@
 
 static constexpr const char kInitContext[] = "u:r:init:s0";
 static constexpr const char kVendorContext[] = "u:r:vendor_init:s0";
+static constexpr const char kTestContext[] = "test-test-test";
 
 class Subcontext {
   public:
diff --git a/init/subcontext_test.cpp b/init/subcontext_test.cpp
index 9c1a788..2e5a256 100644
--- a/init/subcontext_test.cpp
+++ b/init/subcontext_test.cpp
@@ -39,24 +39,12 @@
 namespace android {
 namespace init {
 
-// I would use test fixtures, but I cannot skip the test if not root with them, so instead we have
-// this test runner.
 template <typename F>
 void RunTest(F&& test_function) {
-    if (getuid() != 0) {
-        GTEST_SKIP() << "Skipping test, must be run as root.";
-        return;
-    }
-
-    char* context;
-    ASSERT_EQ(0, getcon(&context));
-    auto context_string = std::string(context);
-    free(context);
-
-    auto subcontext = Subcontext({"dummy_path"}, context_string);
+    auto subcontext = Subcontext({"dummy_path"}, kTestContext);
     ASSERT_NE(0, subcontext.pid());
 
-    test_function(subcontext, context_string);
+    test_function(subcontext);
 
     if (subcontext.pid() > 0) {
         kill(subcontext.pid(), SIGTERM);
@@ -65,7 +53,7 @@
 }
 
 TEST(subcontext, CheckDifferentPid) {
-    RunTest([](auto& subcontext, auto& context_string) {
+    RunTest([](auto& subcontext) {
         auto result = subcontext.Execute(std::vector<std::string>{"return_pids_as_error"});
         ASSERT_FALSE(result);
 
@@ -78,7 +66,12 @@
 }
 
 TEST(subcontext, SetProp) {
-    RunTest([](auto& subcontext, auto& context_string) {
+    if (getuid() != 0) {
+        GTEST_SKIP() << "Skipping test, must be run as root.";
+        return;
+    }
+
+    RunTest([](auto& subcontext) {
         SetProperty("init.test.subcontext", "fail");
         WaitForProperty("init.test.subcontext", "fail");
 
@@ -95,7 +88,7 @@
 }
 
 TEST(subcontext, MultipleCommands) {
-    RunTest([](auto& subcontext, auto& context_string) {
+    RunTest([](auto& subcontext) {
         auto first_pid = subcontext.pid();
 
         auto expected_words = std::vector<std::string>{
@@ -122,7 +115,7 @@
 }
 
 TEST(subcontext, RecoverAfterAbort) {
-    RunTest([](auto& subcontext, auto& context_string) {
+    RunTest([](auto& subcontext) {
         auto first_pid = subcontext.pid();
 
         auto result = subcontext.Execute(std::vector<std::string>{"cause_log_fatal"});
@@ -136,10 +129,10 @@
 }
 
 TEST(subcontext, ContextString) {
-    RunTest([](auto& subcontext, auto& context_string) {
+    RunTest([](auto& subcontext) {
         auto result = subcontext.Execute(std::vector<std::string>{"return_context_as_error"});
         ASSERT_FALSE(result);
-        ASSERT_EQ(context_string, result.error().message());
+        ASSERT_EQ(kTestContext, result.error().message());
     });
 }
 
@@ -147,7 +140,7 @@
     static constexpr const char kTestShutdownCommand[] = "reboot,test-shutdown-command";
     static std::string trigger_shutdown_command;
     trigger_shutdown = [](const std::string& command) { trigger_shutdown_command = command; };
-    RunTest([](auto& subcontext, auto& context_string) {
+    RunTest([](auto& subcontext) {
         auto result = subcontext.Execute(
                 std::vector<std::string>{"trigger_shutdown", kTestShutdownCommand});
         ASSERT_TRUE(result);
@@ -156,7 +149,7 @@
 }
 
 TEST(subcontext, ExpandArgs) {
-    RunTest([](auto& subcontext, auto& context_string) {
+    RunTest([](auto& subcontext) {
         auto args = std::vector<std::string>{
             "first",
             "${ro.hardware}",
@@ -172,7 +165,7 @@
 }
 
 TEST(subcontext, ExpandArgsFailure) {
-    RunTest([](auto& subcontext, auto& context_string) {
+    RunTest([](auto& subcontext) {
         auto args = std::vector<std::string>{
             "first",
             "${",
diff --git a/init/sysprop/Android.bp b/init/sysprop/Android.bp
new file mode 100644
index 0000000..7582875
--- /dev/null
+++ b/init/sysprop/Android.bp
@@ -0,0 +1,7 @@
+sysprop_library {
+  name: "com.android.sysprop.init",
+  srcs: ["InitProperties.sysprop"],
+  property_owner: "Platform",
+  api_packages: ["android.sysprop"],
+  recovery_available: true,
+}
diff --git a/init/sysprop/InitProperties.sysprop b/init/sysprop/InitProperties.sysprop
new file mode 100644
index 0000000..d6a1ab6
--- /dev/null
+++ b/init/sysprop/InitProperties.sysprop
@@ -0,0 +1,27 @@
+# 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.
+
+owner: Platform
+module: "android.sysprop.InitProperties"
+
+# Serves as a signal to all processes that userspace reboot is happening.
+prop {
+    api_name: "userspace_reboot_in_progress"
+    type: Boolean
+    scope: Public
+    access: ReadWrite
+    prop_name: "sys.init.userspace_reboot.in_progress"
+    integer_as_bool: true
+}
+
diff --git a/init/sysprop/api/com.android.sysprop.init-current.txt b/init/sysprop/api/com.android.sysprop.init-current.txt
new file mode 100644
index 0000000..8da50e0
--- /dev/null
+++ b/init/sysprop/api/com.android.sysprop.init-current.txt
@@ -0,0 +1,9 @@
+props {
+  module: "android.sysprop.InitProperties"
+  prop {
+    api_name: "userspace_reboot_in_progress"
+    access: ReadWrite
+    prop_name: "sys.init.userspace_reboot.in_progress"
+    integer_as_bool: true
+  }
+}
diff --git a/init/sysprop/api/com.android.sysprop.init-latest.txt b/init/sysprop/api/com.android.sysprop.init-latest.txt
new file mode 100644
index 0000000..c835b95
--- /dev/null
+++ b/init/sysprop/api/com.android.sysprop.init-latest.txt
@@ -0,0 +1,9 @@
+props {
+  module: "android.sysprop.InitProperties"
+  prop {
+    api_name: "userspace_reboot_in_progress"
+    scope: Public
+    prop_name: "sys.init.userspace_reboot.in_progress"
+    integer_as_bool: true
+  }
+}
diff --git a/liblog/event_tag_map.cpp b/liblog/event_tag_map.cpp
index 22cf43b..2886289 100644
--- a/liblog/event_tag_map.cpp
+++ b/liblog/event_tag_map.cpp
@@ -494,7 +494,7 @@
 
 // Cache miss, go to logd to acquire a public reference.
 // Because we lack access to a SHARED PUBLIC /dev/event-log-tags file map?
-static const TagFmt* __getEventTag(EventTagMap* map, unsigned int tag) {
+static const TagFmt* __getEventTag([[maybe_unused]] EventTagMap* map, unsigned int tag) {
   // call event tag service to arrange for a new tag
   char* buf = NULL;
   // Can not use android::base::StringPrintf, asprintf + free instead.
@@ -515,8 +515,9 @@
     } else {
       size = ret;
     }
+#ifdef __ANDROID__
     // Ask event log tag service for an existing entry
-    if (__send_log_msg(buf, size) >= 0) {
+    if (SendLogdControlMessage(buf, size) >= 0) {
       buf[size - 1] = '\0';
       char* ep;
       unsigned long val = strtoul(buf, &ep, 10);  // return size
@@ -529,6 +530,7 @@
         }
       }
     }
+#endif
     free(buf);
   }
   return NULL;
@@ -618,8 +620,9 @@
     } else {
       size = ret;
     }
+#ifdef __ANDROID__
     // Ask event log tag service for an allocation
-    if (__send_log_msg(buf, size) >= 0) {
+    if (SendLogdControlMessage(buf, size) >= 0) {
       buf[size - 1] = '\0';
       unsigned long val = strtoul(buf, &cp, 10);        // return size
       if ((buf != cp) && (val > 0) && (*cp == '\n')) {  // truncation OK
@@ -635,6 +638,7 @@
         }
       }
     }
+#endif
     free(buf);
   }
 
diff --git a/liblog/fake_log_device.cpp b/liblog/fake_log_device.cpp
index 428a482..f61bbdc 100644
--- a/liblog/fake_log_device.cpp
+++ b/liblog/fake_log_device.cpp
@@ -650,10 +650,6 @@
   return fd;
 }
 
-ssize_t __send_log_msg(char*, size_t) {
-  return -ENODEV;
-}
-
 int __android_log_is_loggable(int prio, const char*, int def) {
   int logLevel = def;
   return logLevel >= 0 && prio >= logLevel;
diff --git a/liblog/fake_log_device.h b/liblog/fake_log_device.h
index ce54db2..bd2256c 100644
--- a/liblog/fake_log_device.h
+++ b/liblog/fake_log_device.h
@@ -29,7 +29,6 @@
 int fakeLogClose(int fd);
 ssize_t fakeLogWritev(int fd, const struct iovec* vector, int count);
 
-ssize_t __send_log_msg(char*, size_t);
 int __android_log_is_loggable(int prio, const char*, int def);
 int __android_log_is_loggable_len(int prio, const char*, size_t, int def);
 int __android_log_is_debuggable();
diff --git a/liblog/logd_reader.cpp b/liblog/logd_reader.cpp
index eaa157a..96e7a61 100644
--- a/liblog/logd_reader.cpp
+++ b/liblog/logd_reader.cpp
@@ -14,6 +14,8 @@
  * limitations under the License.
  */
 
+#include "logd_reader.h"
+
 #include <errno.h>
 #include <fcntl.h>
 #include <inttypes.h>
@@ -35,62 +37,8 @@
 #include <private/android_filesystem_config.h>
 #include <private/android_logger.h>
 
-#include "log_portability.h"
-#include "logd_reader.h"
 #include "logger.h"
 
-static int LogdAvailable(log_id_t LogId);
-static int LogdVersion(struct logger* logger, struct android_log_transport_context* transp);
-static int LogdRead(struct logger_list* logger_list, struct android_log_transport_context* transp,
-                    struct log_msg* log_msg);
-static int LogdPoll(struct logger_list* logger_list, struct android_log_transport_context* transp);
-static void LogdClose(struct logger_list* logger_list,
-                      struct android_log_transport_context* transp);
-static int LogdClear(struct logger* logger, struct android_log_transport_context* transp);
-static ssize_t LogdSetSize(struct logger* logger, struct android_log_transport_context* transp,
-                           size_t size);
-static ssize_t LogdGetSize(struct logger* logger, struct android_log_transport_context* transp);
-static ssize_t LogdGetReadableSize(struct logger* logger,
-                                   struct android_log_transport_context* transp);
-static ssize_t LogdGetPrune(struct logger_list* logger,
-                            struct android_log_transport_context* transp, char* buf, size_t len);
-static ssize_t LogdSetPrune(struct logger_list* logger,
-                            struct android_log_transport_context* transp, char* buf, size_t len);
-static ssize_t LogdGetStats(struct logger_list* logger,
-                            struct android_log_transport_context* transp, char* buf, size_t len);
-
-struct android_log_transport_read logdLoggerRead = {
-    .name = "logd",
-    .available = LogdAvailable,
-    .version = LogdVersion,
-    .close = LogdClose,
-    .read = LogdRead,
-    .poll = LogdPoll,
-    .clear = LogdClear,
-    .setSize = LogdSetSize,
-    .getSize = LogdGetSize,
-    .getReadableSize = LogdGetReadableSize,
-    .getPrune = LogdGetPrune,
-    .setPrune = LogdSetPrune,
-    .getStats = LogdGetStats,
-};
-
-static int LogdAvailable(log_id_t logId) {
-  if (logId >= LOG_ID_MAX) {
-    return -EINVAL;
-  }
-  if (logId == LOG_ID_SECURITY) {
-    uid_t uid = __android_log_uid();
-    if (uid != AID_SYSTEM) {
-      return -EPERM;
-    }
-  }
-  if (access("/dev/socket/logdw", W_OK) == 0) {
-    return 0;
-  }
-  return -EBADF;
-}
-
 // Connects to /dev/socket/<name> and returns the associated fd or returns -1 on error.
 // O_CLOEXEC is always set.
 static int socket_local_client(const std::string& name, int type) {
@@ -116,7 +64,7 @@
 }
 
 /* worker for sending the command to the logger */
-static ssize_t send_log_msg(struct logger* logger, const char* msg, char* buf, size_t buf_size) {
+ssize_t SendLogdControlMessage(char* buf, size_t buf_size) {
   ssize_t ret;
   size_t len;
   char* cp;
@@ -126,10 +74,6 @@
     return sock;
   }
 
-  if (msg) {
-    snprintf(buf, buf_size, msg, logger ? logger->logId : (unsigned)-1);
-  }
-
   len = strlen(buf) + 1;
   ret = TEMP_FAILURE_RETRY(write(sock, buf, len));
   if (ret <= 0) {
@@ -180,10 +124,6 @@
   return ret;
 }
 
-ssize_t __send_log_msg(char* buf, size_t buf_size) {
-  return send_log_msg(NULL, NULL, buf, buf_size);
-}
-
 static int check_log_success(char* buf, ssize_t ret) {
   if (ret < 0) {
     return ret;
@@ -197,17 +137,28 @@
   return 0;
 }
 
-static int LogdClear(struct logger* logger, struct android_log_transport_context*) {
+int android_logger_clear(struct logger* logger) {
+  if (!android_logger_is_logd(logger)) {
+    return -EINVAL;
+  }
+  uint32_t log_id = android_logger_get_id(logger);
   char buf[512];
+  snprintf(buf, sizeof(buf), "clear %" PRIu32, log_id);
 
-  return check_log_success(buf, send_log_msg(logger, "clear %d", buf, sizeof(buf)));
+  return check_log_success(buf, SendLogdControlMessage(buf, sizeof(buf)));
 }
 
 /* returns the total size of the log's ring buffer */
-static ssize_t LogdGetSize(struct logger* logger, struct android_log_transport_context*) {
-  char buf[512];
+long android_logger_get_log_size(struct logger* logger) {
+  if (!android_logger_is_logd(logger)) {
+    return -EINVAL;
+  }
 
-  ssize_t ret = send_log_msg(logger, "getLogSize %d", buf, sizeof(buf));
+  uint32_t log_id = android_logger_get_id(logger);
+  char buf[512];
+  snprintf(buf, sizeof(buf), "getLogSize %" PRIu32, log_id);
+
+  ssize_t ret = SendLogdControlMessage(buf, sizeof(buf));
   if (ret < 0) {
     return ret;
   }
@@ -219,23 +170,32 @@
   return atol(buf);
 }
 
-static ssize_t LogdSetSize(struct logger* logger, struct android_log_transport_context*,
-                           size_t size) {
+int android_logger_set_log_size(struct logger* logger, unsigned long size) {
+  if (!android_logger_is_logd(logger)) {
+    return -EINVAL;
+  }
+
+  uint32_t log_id = android_logger_get_id(logger);
   char buf[512];
+  snprintf(buf, sizeof(buf), "setLogSize %" PRIu32 " %lu", log_id, size);
 
-  snprintf(buf, sizeof(buf), "setLogSize %d %zu", logger->logId, size);
-
-  return check_log_success(buf, send_log_msg(NULL, NULL, buf, sizeof(buf)));
+  return check_log_success(buf, SendLogdControlMessage(buf, sizeof(buf)));
 }
 
 /*
  * returns the readable size of the log's ring buffer (that is, amount of the
  * log consumed)
  */
-static ssize_t LogdGetReadableSize(struct logger* logger, struct android_log_transport_context*) {
-  char buf[512];
+long android_logger_get_log_readable_size(struct logger* logger) {
+  if (!android_logger_is_logd(logger)) {
+    return -EINVAL;
+  }
 
-  ssize_t ret = send_log_msg(logger, "getLogSizeUsed %d", buf, sizeof(buf));
+  uint32_t log_id = android_logger_get_id(logger);
+  char buf[512];
+  snprintf(buf, sizeof(buf), "getLogSizeUsed %" PRIu32, log_id);
+
+  ssize_t ret = SendLogdControlMessage(buf, sizeof(buf));
   if (ret < 0) {
     return ret;
   }
@@ -247,20 +207,15 @@
   return atol(buf);
 }
 
-/*
- * returns the logger version
- */
-static int LogdVersion(struct logger*, struct android_log_transport_context*) {
-  uid_t uid = __android_log_uid();
-  return ((uid != AID_ROOT) && (uid != AID_LOG) && (uid != AID_SYSTEM)) ? 3 : 4;
+int android_logger_get_log_version(struct logger*) {
+  return 4;
 }
 
-/*
- * returns statistics
- */
-static ssize_t LogdGetStats(struct logger_list* logger_list, struct android_log_transport_context*,
-                            char* buf, size_t len) {
-  struct logger* logger;
+ssize_t android_logger_get_statistics(struct logger_list* logger_list, char* buf, size_t len) {
+  if (logger_list->mode & ANDROID_LOG_PSTORE) {
+    return -EINVAL;
+  }
+
   char* cp = buf;
   size_t remaining = len;
   size_t n;
@@ -270,27 +225,35 @@
   remaining -= n;
   cp += n;
 
-  logger_for_each(logger, logger_list) {
-    n = snprintf(cp, remaining, " %d", logger->logId);
-    n = MIN(n, remaining);
-    remaining -= n;
-    cp += n;
+  for (size_t log_id = 0; log_id < LOG_ID_MAX; ++log_id) {
+    if ((1 << log_id) & logger_list->log_mask) {
+      n = snprintf(cp, remaining, " %zu", log_id);
+      n = MIN(n, remaining);
+      remaining -= n;
+      cp += n;
+    }
   }
 
   if (logger_list->pid) {
     snprintf(cp, remaining, " pid=%u", logger_list->pid);
   }
 
-  return send_log_msg(NULL, NULL, buf, len);
+  return SendLogdControlMessage(buf, len);
+}
+ssize_t android_logger_get_prune_list(struct logger_list* logger_list, char* buf, size_t len) {
+  if (logger_list->mode & ANDROID_LOG_PSTORE) {
+    return -EINVAL;
+  }
+
+  snprintf(buf, len, "getPruneList");
+  return SendLogdControlMessage(buf, len);
 }
 
-static ssize_t LogdGetPrune(struct logger_list*, struct android_log_transport_context*, char* buf,
-                            size_t len) {
-  return send_log_msg(NULL, "getPruneList", buf, len);
-}
+int android_logger_set_prune_list(struct logger_list* logger_list, char* buf, size_t len) {
+  if (logger_list->mode & ANDROID_LOG_PSTORE) {
+    return -EINVAL;
+  }
 
-static ssize_t LogdSetPrune(struct logger_list*, struct android_log_transport_context*, char* buf,
-                            size_t len) {
   const char cmd[] = "setPruneList ";
   const size_t cmdlen = sizeof(cmd) - 1;
 
@@ -301,19 +264,14 @@
   buf[len - 1] = '\0';
   memcpy(buf, cmd, cmdlen);
 
-  return check_log_success(buf, send_log_msg(NULL, NULL, buf, len));
+  return check_log_success(buf, SendLogdControlMessage(buf, len));
 }
 
-static int logdOpen(struct logger_list* logger_list, struct android_log_transport_context* transp) {
-  struct logger* logger;
+static int logdOpen(struct logger_list* logger_list) {
   char buffer[256], *cp, c;
   int ret, remaining, sock;
 
-  if (!logger_list) {
-    return -EINVAL;
-  }
-
-  sock = atomic_load(&transp->context.sock);
+  sock = atomic_load(&logger_list->fd);
   if (sock > 0) {
     return sock;
   }
@@ -333,12 +291,15 @@
   cp += 5;
   c = '=';
   remaining = sizeof(buffer) - (cp - buffer);
-  logger_for_each(logger, logger_list) {
-    ret = snprintf(cp, remaining, "%c%u", c, logger->logId);
-    ret = MIN(ret, remaining);
-    remaining -= ret;
-    cp += ret;
-    c = ',';
+
+  for (size_t log_id = 0; log_id < LOG_ID_MAX; ++log_id) {
+    if ((1 << log_id) & logger_list->log_mask) {
+      ret = snprintf(cp, remaining, "%c%zu", c, log_id);
+      ret = MIN(ret, remaining);
+      remaining -= ret;
+      cp += ret;
+      c = ',';
+    }
   }
 
   if (logger_list->tail) {
@@ -383,7 +344,7 @@
     return ret;
   }
 
-  ret = atomic_exchange(&transp->context.sock, sock);
+  ret = atomic_exchange(&logger_list->fd, sock);
   if ((ret > 0) && (ret != sock)) {
     close(ret);
   }
@@ -391,15 +352,12 @@
 }
 
 /* Read from the selected logs */
-static int LogdRead(struct logger_list* logger_list, struct android_log_transport_context* transp,
-                    struct log_msg* log_msg) {
-  int ret = logdOpen(logger_list, transp);
+int LogdRead(struct logger_list* logger_list, struct log_msg* log_msg) {
+  int ret = logdOpen(logger_list);
   if (ret < 0) {
     return ret;
   }
 
-  memset(log_msg, 0, sizeof(*log_msg));
-
   /* NOTE: SOCK_SEQPACKET guarantees we read exactly one full entry */
   ret = TEMP_FAILURE_RETRY(recv(ret, log_msg, LOGGER_ENTRY_MAX_LEN, 0));
   if ((logger_list->mode & ANDROID_LOG_NONBLOCK) && ret == 0) {
@@ -412,30 +370,9 @@
   return ret;
 }
 
-static int LogdPoll(struct logger_list* logger_list, struct android_log_transport_context* transp) {
-  struct pollfd p;
-
-  int ret = logdOpen(logger_list, transp);
-  if (ret < 0) {
-    return ret;
-  }
-
-  memset(&p, 0, sizeof(p));
-  p.fd = ret;
-  p.events = POLLIN;
-  ret = poll(&p, 1, 20);
-  if ((ret > 0) && !(p.revents & POLLIN)) {
-    ret = 0;
-  }
-  if ((ret == -1) && errno) {
-    return -errno;
-  }
-  return ret;
-}
-
 /* Close all the logs */
-static void LogdClose(struct logger_list*, struct android_log_transport_context* transp) {
-  int sock = atomic_exchange(&transp->context.sock, -1);
+void LogdClose(struct logger_list* logger_list) {
+  int sock = atomic_exchange(&logger_list->fd, -1);
   if (sock > 0) {
     close(sock);
   }
diff --git a/liblog/logd_reader.h b/liblog/logd_reader.h
index 7c53cbb..2d032fa 100644
--- a/liblog/logd_reader.h
+++ b/liblog/logd_reader.h
@@ -18,10 +18,14 @@
 
 #include <unistd.h>
 
+#include "log/log_read.h"
 #include "log_portability.h"
 
 __BEGIN_DECLS
 
-ssize_t __send_log_msg(char* buf, size_t buf_size);
+int LogdRead(struct logger_list* logger_list, struct log_msg* log_msg);
+void LogdClose(struct logger_list* logger_list);
+
+ssize_t SendLogdControlMessage(char* buf, size_t buf_size);
 
 __END_DECLS
diff --git a/liblog/logger.h b/liblog/logger.h
index 9c488b6..9d74d29 100644
--- a/liblog/logger.h
+++ b/liblog/logger.h
@@ -46,69 +46,28 @@
                size_t nr);
 };
 
-struct android_log_transport_context;
-
-struct android_log_transport_read {
-  const char* name; /* human name to describe the transport */
-
-  /* Does not cause resources to be taken */
-  int (*available)(log_id_t logId);
-  int (*version)(struct logger* logger, struct android_log_transport_context* transp);
-  /* Release resources taken by the following interfaces */
-  void (*close)(struct logger_list* logger_list, struct android_log_transport_context* transp);
-  /*
-   * Expect all to instantiate open automagically on any call,
-   * so we do not have an explicit open call.
-   */
-  int (*read)(struct logger_list* logger_list, struct android_log_transport_context* transp,
-              struct log_msg* log_msg);
-  /* Must only be called if not ANDROID_LOG_NONBLOCK (blocking) */
-  int (*poll)(struct logger_list* logger_list, struct android_log_transport_context* transp);
-
-  int (*clear)(struct logger* logger, struct android_log_transport_context* transp);
-  ssize_t (*setSize)(struct logger* logger, struct android_log_transport_context* transp,
-                     size_t size);
-  ssize_t (*getSize)(struct logger* logger, struct android_log_transport_context* transp);
-  ssize_t (*getReadableSize)(struct logger* logger, struct android_log_transport_context* transp);
-
-  ssize_t (*getPrune)(struct logger_list* logger_list, struct android_log_transport_context* transp,
-                      char* buf, size_t len);
-  ssize_t (*setPrune)(struct logger_list* logger_list, struct android_log_transport_context* transp,
-                      char* buf, size_t len);
-  ssize_t (*getStats)(struct logger_list* logger_list, struct android_log_transport_context* transp,
-                      char* buf, size_t len);
-};
-
-struct android_log_transport_context {
-  union android_log_context_union context; /* zero init per-transport context */
-
-  struct android_log_transport_read* transport;
-  unsigned logMask;      /* mask of requested log buffers */
-};
-
 struct logger_list {
-  struct listnode logger;
-  android_log_transport_context transport_context;
-  bool transport_initialized;
+  atomic_int fd;
   int mode;
   unsigned int tail;
   log_time start;
   pid_t pid;
+  uint32_t log_mask;
 };
 
-struct logger {
-  struct listnode node;
-  struct logger_list* parent;
+// Format for a 'logger' entry: uintptr_t where only the bottom 32 bits are used.
+// bit 31: Set if this 'logger' is for logd.
+// bit 30: Set if this 'logger' is for pmsg
+// bits 0-2: the decimal value of the log buffer.
+// Other bits are unused.
 
-  log_id_t logId;
-};
+#define LOGGER_LOGD (1U << 31)
+#define LOGGER_PMSG (1U << 30)
+#define LOGGER_LOG_ID_MASK ((1U << 3) - 1)
 
-/* assumes caller has structures read-locked, single threaded, or fenced */
-#define logger_for_each(logp, logger_list)                                      \
-  for ((logp) = node_to_item((logger_list)->logger.next, struct logger, node);  \
-       ((logp) != node_to_item(&(logger_list)->logger, struct logger, node)) && \
-       ((logp)->parent == (logger_list));                                       \
-       (logp) = node_to_item((logp)->node.next, struct logger, node))
+inline bool android_logger_is_logd(struct logger* logger) {
+  return reinterpret_cast<uintptr_t>(logger) & LOGGER_LOGD;
+}
 
 /* OS specific dribs and drabs */
 
diff --git a/liblog/logger_read.cpp b/liblog/logger_read.cpp
index 5e10ada..c65501c 100644
--- a/liblog/logger_read.cpp
+++ b/liblog/logger_read.cpp
@@ -21,6 +21,7 @@
 #include <pthread.h>
 #include <sched.h>
 #include <stddef.h>
+#include <stdint.h>
 #include <stdlib.h>
 #include <string.h>
 #include <unistd.h>
@@ -30,213 +31,49 @@
 #include <private/android_filesystem_config.h>
 
 #include "log_portability.h"
+#include "logd_reader.h"
 #include "logger.h"
-
-/* android_logger_alloc unimplemented, no use case */
-/* android_logger_free not exported */
-static void android_logger_free(struct logger* logger) {
-  if (!logger) {
-    return;
-  }
-
-  list_remove(&logger->node);
-
-  free(logger);
-}
-
-/* android_logger_alloc unimplemented, no use case */
+#include "pmsg_reader.h"
 
 /* method for getting the associated sublog id */
 log_id_t android_logger_get_id(struct logger* logger) {
-  return ((struct logger*)logger)->logId;
+  return static_cast<log_id_t>(reinterpret_cast<uintptr_t>(logger) & LOGGER_LOG_ID_MASK);
 }
 
-static int init_transport_context(struct logger_list* logger_list) {
+static struct logger_list* android_logger_list_alloc_internal(int mode, unsigned int tail,
+                                                              log_time start, pid_t pid) {
+  auto* logger_list = static_cast<struct logger_list*>(calloc(1, sizeof(struct logger_list)));
   if (!logger_list) {
-    return -EINVAL;
+    return nullptr;
   }
 
-  if (list_empty(&logger_list->logger)) {
-    return -EINVAL;
-  }
-
-  if (logger_list->transport_initialized) {
-    return 0;
-  }
-
-#if (FAKE_LOG_DEVICE == 0)
-  extern struct android_log_transport_read logdLoggerRead;
-  extern struct android_log_transport_read pmsgLoggerRead;
-
-  struct android_log_transport_read* transport;
-  transport = (logger_list->mode & ANDROID_LOG_PSTORE) ? &pmsgLoggerRead : &logdLoggerRead;
-
-  struct logger* logger;
-  unsigned logMask = 0;
-
-  logger_for_each(logger, logger_list) {
-    log_id_t logId = logger->logId;
-
-    if (logId == LOG_ID_SECURITY && __android_log_uid() != AID_SYSTEM) {
-      continue;
-    }
-    if (transport->read && (!transport->available || transport->available(logId) >= 0)) {
-      logMask |= 1 << logId;
-    }
-  }
-  if (!logMask) {
-    return -ENODEV;
-  }
-
-  logger_list->transport_context.transport = transport;
-  logger_list->transport_context.logMask = logMask;
-#endif
-  return 0;
-}
-
-#define LOGGER_FUNCTION(logger, def, func, args...)                                           \
-  ssize_t ret = -EINVAL;                                                                      \
-                                                                                              \
-  if (!logger) {                                                                              \
-    return ret;                                                                               \
-  }                                                                                           \
-  ret = init_transport_context(logger->parent);                                               \
-  if (ret < 0) {                                                                              \
-    return ret;                                                                               \
-  }                                                                                           \
-                                                                                              \
-  ret = (def);                                                                                \
-  android_log_transport_context* transport_context = &logger->parent->transport_context;      \
-  if (transport_context->logMask & (1 << logger->logId) && transport_context->transport &&    \
-      transport_context->transport->func) {                                                   \
-    ssize_t retval = (transport_context->transport->func)(logger, transport_context, ##args); \
-    if (ret >= 0 || ret == (def)) {                                                           \
-      ret = retval;                                                                           \
-    }                                                                                         \
-  }                                                                                           \
-  return ret
-
-int android_logger_clear(struct logger* logger) {
-  LOGGER_FUNCTION(logger, -ENODEV, clear);
-}
-
-/* returns the total size of the log's ring buffer */
-long android_logger_get_log_size(struct logger* logger) {
-  LOGGER_FUNCTION(logger, -ENODEV, getSize);
-}
-
-int android_logger_set_log_size(struct logger* logger, unsigned long size) {
-  LOGGER_FUNCTION(logger, -ENODEV, setSize, size);
-}
-
-/*
- * returns the readable size of the log's ring buffer (that is, amount of the
- * log consumed)
- */
-long android_logger_get_log_readable_size(struct logger* logger) {
-  LOGGER_FUNCTION(logger, -ENODEV, getReadableSize);
-}
-
-/*
- * returns the logger version
- */
-int android_logger_get_log_version(struct logger* logger) {
-  LOGGER_FUNCTION(logger, 4, version);
-}
-
-#define LOGGER_LIST_FUNCTION(logger_list, def, func, args...)                                      \
-  ssize_t ret = init_transport_context(logger_list);                                               \
-  if (ret < 0) {                                                                                   \
-    return ret;                                                                                    \
-  }                                                                                                \
-                                                                                                   \
-  ret = (def);                                                                                     \
-  android_log_transport_context* transport_context = &logger_list->transport_context;              \
-  if (transport_context->transport && transport_context->transport->func) {                        \
-    ssize_t retval = (transport_context->transport->func)(logger_list, transport_context, ##args); \
-    if (ret >= 0 || ret == (def)) {                                                                \
-      ret = retval;                                                                                \
-    }                                                                                              \
-  }                                                                                                \
-  return ret
-
-/*
- * returns statistics
- */
-ssize_t android_logger_get_statistics(struct logger_list* logger_list, char* buf, size_t len) {
-  LOGGER_LIST_FUNCTION(logger_list, -ENODEV, getStats, buf, len);
-}
-
-ssize_t android_logger_get_prune_list(struct logger_list* logger_list, char* buf, size_t len) {
-  LOGGER_LIST_FUNCTION(logger_list, -ENODEV, getPrune, buf, len);
-}
-
-int android_logger_set_prune_list(struct logger_list* logger_list, char* buf, size_t len) {
-  LOGGER_LIST_FUNCTION(logger_list, -ENODEV, setPrune, buf, len);
-}
-
-struct logger_list* android_logger_list_alloc(int mode, unsigned int tail, pid_t pid) {
-  struct logger_list* logger_list;
-
-  logger_list = static_cast<struct logger_list*>(calloc(1, sizeof(*logger_list)));
-  if (!logger_list) {
-    return NULL;
-  }
-
-  list_init(&logger_list->logger);
   logger_list->mode = mode;
+  logger_list->start = start;
   logger_list->tail = tail;
   logger_list->pid = pid;
 
   return logger_list;
 }
 
-struct logger_list* android_logger_list_alloc_time(int mode, log_time start, pid_t pid) {
-  struct logger_list* logger_list;
-
-  logger_list = static_cast<struct logger_list*>(calloc(1, sizeof(*logger_list)));
-  if (!logger_list) {
-    return NULL;
-  }
-
-  list_init(&logger_list->logger);
-  logger_list->mode = mode;
-  logger_list->start = start;
-  logger_list->pid = pid;
-
-  return logger_list;
+struct logger_list* android_logger_list_alloc(int mode, unsigned int tail, pid_t pid) {
+  return android_logger_list_alloc_internal(mode, tail, log_time(0, 0), pid);
 }
 
-/* android_logger_list_register unimplemented, no use case */
-/* android_logger_list_unregister unimplemented, no use case */
+struct logger_list* android_logger_list_alloc_time(int mode, log_time start, pid_t pid) {
+  return android_logger_list_alloc_internal(mode, 0, start, pid);
+}
 
 /* Open the named log and add it to the logger list */
 struct logger* android_logger_open(struct logger_list* logger_list, log_id_t logId) {
-  struct logger* logger;
-
   if (!logger_list || (logId >= LOG_ID_MAX)) {
     return nullptr;
   }
 
-  logger_for_each(logger, logger_list) {
-    if (logger->logId == logId) {
-      return reinterpret_cast<struct logger*>(logger);
-    }
-  }
+  logger_list->log_mask |= 1 << logId;
 
-  logger = static_cast<struct logger*>(calloc(1, sizeof(*logger)));
-  if (!logger) {
-    return nullptr;
-  }
-
-  logger->logId = logId;
-  list_add_tail(&logger_list->logger, &logger->node);
-  logger->parent = logger_list;
-
-  // Reset known transport to re-evaluate, since we added a new logger.
-  logger_list->transport_initialized = false;
-
-  return logger;
+  uintptr_t logger = logId;
+  logger |= (logger_list->mode & ANDROID_LOG_PSTORE) ? LOGGER_PMSG : LOGGER_LOGD;
+  return reinterpret_cast<struct logger*>(logger);
 }
 
 /* Open the single named log and make it part of a new logger list */
@@ -256,13 +93,22 @@
   return logger_list;
 }
 
-/* Validate log_msg packet, read function has already been null checked */
-static int android_transport_read(struct logger_list* logger_list,
-                                  struct android_log_transport_context* transp,
-                                  struct log_msg* log_msg) {
-  int ret = (*transp->transport->read)(logger_list, transp, log_msg);
+int android_logger_list_read(struct logger_list* logger_list, struct log_msg* log_msg) {
+  if (logger_list == nullptr || logger_list->log_mask == 0) {
+    return -EINVAL;
+  }
 
-  if (ret < 0) {
+  int ret = 0;
+
+#if (FAKE_LOG_DEVICE == 0)
+  if (logger_list->mode & ANDROID_LOG_PSTORE) {
+    ret = PmsgRead(logger_list, log_msg);
+  } else {
+    ret = LogdRead(logger_list, log_msg);
+  }
+#endif
+
+  if (ret <= 0) {
     return ret;
   }
 
@@ -285,34 +131,19 @@
   return ret;
 }
 
-/* Read from the selected logs */
-int android_logger_list_read(struct logger_list* logger_list, struct log_msg* log_msg) {
-  int ret = init_transport_context(logger_list);
-  if (ret < 0) {
-    return ret;
-  }
-
-  android_log_transport_context* transport_context = &logger_list->transport_context;
-  return android_transport_read(logger_list, transport_context, log_msg);
-}
-
 /* Close all the logs */
 void android_logger_list_free(struct logger_list* logger_list) {
   if (logger_list == NULL) {
     return;
   }
 
-  android_log_transport_context* transport_context = &logger_list->transport_context;
-
-  if (transport_context->transport && transport_context->transport->close) {
-    (*transport_context->transport->close)(logger_list, transport_context);
+#if (FAKE_LOG_DEVICE == 0)
+  if (logger_list->mode & ANDROID_LOG_PSTORE) {
+    PmsgClose(logger_list);
+  } else {
+    LogdClose(logger_list);
   }
-
-  while (!list_empty(&logger_list->logger)) {
-    struct listnode* node = list_head(&logger_list->logger);
-    struct logger* logger = node_to_item(node, struct logger, node);
-    android_logger_free((struct logger*)logger);
-  }
+#endif
 
   free(logger_list);
 }
diff --git a/liblog/pmsg_reader.cpp b/liblog/pmsg_reader.cpp
index cd83161..9390fec 100644
--- a/liblog/pmsg_reader.cpp
+++ b/liblog/pmsg_reader.cpp
@@ -14,6 +14,8 @@
  * limitations under the License.
  */
 
+#include "pmsg_reader.h"
+
 #include <ctype.h>
 #include <errno.h>
 #include <fcntl.h>
@@ -26,53 +28,7 @@
 
 #include "logger.h"
 
-static int PmsgAvailable(log_id_t logId);
-static int PmsgVersion(struct logger* logger, struct android_log_transport_context* transp);
-static int PmsgRead(struct logger_list* logger_list, struct android_log_transport_context* transp,
-                    struct log_msg* log_msg);
-static void PmsgClose(struct logger_list* logger_list,
-                      struct android_log_transport_context* transp);
-static int PmsgClear(struct logger* logger, struct android_log_transport_context* transp);
-
-struct android_log_transport_read pmsgLoggerRead = {
-    .name = "pmsg",
-    .available = PmsgAvailable,
-    .version = PmsgVersion,
-    .close = PmsgClose,
-    .read = PmsgRead,
-    .poll = NULL,
-    .clear = PmsgClear,
-    .setSize = NULL,
-    .getSize = NULL,
-    .getReadableSize = NULL,
-    .getPrune = NULL,
-    .setPrune = NULL,
-    .getStats = NULL,
-};
-
-static int PmsgAvailable(log_id_t logId) {
-  if (logId > LOG_ID_SECURITY) {
-    return -EINVAL;
-  }
-  if (access("/dev/pmsg0", W_OK) == 0) {
-    return 0;
-  }
-  return -EBADF;
-}
-
-static int PmsgClear(struct logger*, struct android_log_transport_context*) {
-  return unlink("/sys/fs/pstore/pmsg-ramoops-0");
-}
-
-/*
- * returns the logger version
- */
-static int PmsgVersion(struct logger*, struct android_log_transport_context*) {
-  return 4;
-}
-
-static int PmsgRead(struct logger_list* logger_list, struct android_log_transport_context* transp,
-                    struct log_msg* log_msg) {
+int PmsgRead(struct logger_list* logger_list, struct log_msg* log_msg) {
   ssize_t ret;
   off_t current, next;
   struct __attribute__((__packed__)) {
@@ -84,7 +40,7 @@
 
   memset(log_msg, 0, sizeof(*log_msg));
 
-  if (atomic_load(&transp->context.fd) <= 0) {
+  if (atomic_load(&logger_list->fd) <= 0) {
     int i, fd = open("/sys/fs/pstore/pmsg-ramoops-0", O_RDONLY | O_CLOEXEC);
 
     if (fd < 0) {
@@ -97,7 +53,7 @@
         return -errno;
       }
     }
-    i = atomic_exchange(&transp->context.fd, fd);
+    i = atomic_exchange(&logger_list->fd, fd);
     if ((i > 0) && (i != fd)) {
       close(i);
     }
@@ -108,7 +64,7 @@
     int fd;
 
     if (preread_count < sizeof(buf)) {
-      fd = atomic_load(&transp->context.fd);
+      fd = atomic_load(&logger_list->fd);
       if (fd <= 0) {
         return -EBADF;
       }
@@ -134,7 +90,7 @@
     }
     preread_count = 0;
 
-    if ((transp->logMask & (1 << buf.l.id)) &&
+    if ((logger_list->log_mask & (1 << buf.l.id)) &&
         ((!logger_list->start.tv_sec && !logger_list->start.tv_nsec) ||
          ((logger_list->start.tv_sec <= buf.l.realtime.tv_sec) &&
           ((logger_list->start.tv_sec != buf.l.realtime.tv_sec) ||
@@ -142,7 +98,7 @@
         (!logger_list->pid || (logger_list->pid == buf.p.pid))) {
       char* msg = log_msg->entry.msg;
       *msg = buf.prio;
-      fd = atomic_load(&transp->context.fd);
+      fd = atomic_load(&logger_list->fd);
       if (fd <= 0) {
         return -EBADF;
       }
@@ -166,7 +122,7 @@
       return ret + sizeof(buf.prio) + log_msg->entry.hdr_size;
     }
 
-    fd = atomic_load(&transp->context.fd);
+    fd = atomic_load(&logger_list->fd);
     if (fd <= 0) {
       return -EBADF;
     }
@@ -174,7 +130,7 @@
     if (current < 0) {
       return -errno;
     }
-    fd = atomic_load(&transp->context.fd);
+    fd = atomic_load(&logger_list->fd);
     if (fd <= 0) {
       return -EBADF;
     }
@@ -188,8 +144,8 @@
   }
 }
 
-static void PmsgClose(struct logger_list*, struct android_log_transport_context* transp) {
-  int fd = atomic_exchange(&transp->context.fd, 0);
+void PmsgClose(struct logger_list* logger_list) {
+  int fd = atomic_exchange(&logger_list->fd, 0);
   if (fd > 0) {
     close(fd);
   }
@@ -207,7 +163,6 @@
                                      __android_log_pmsg_file_read_fn fn, void* arg) {
   ssize_t ret;
   struct logger_list logger_list;
-  struct android_log_transport_context transp;
   struct content {
     struct listnode node;
     struct logger_entry entry;
@@ -229,15 +184,14 @@
 
   /* Add just enough clues in logger_list and transp to make API function */
   memset(&logger_list, 0, sizeof(logger_list));
-  memset(&transp, 0, sizeof(transp));
 
   logger_list.mode = ANDROID_LOG_PSTORE | ANDROID_LOG_NONBLOCK | ANDROID_LOG_RDONLY;
-  transp.logMask = (unsigned)-1;
+  logger_list.log_mask = (unsigned)-1;
   if (logId != LOG_ID_ANY) {
-    transp.logMask = (1 << logId);
+    logger_list.log_mask = (1 << logId);
   }
-  transp.logMask &= ~((1 << LOG_ID_KERNEL) | (1 << LOG_ID_EVENTS) | (1 << LOG_ID_SECURITY));
-  if (!transp.logMask) {
+  logger_list.log_mask &= ~((1 << LOG_ID_KERNEL) | (1 << LOG_ID_EVENTS) | (1 << LOG_ID_SECURITY));
+  if (!logger_list.log_mask) {
     return -EINVAL;
   }
 
@@ -263,7 +217,7 @@
 
   /* Read the file content */
   log_msg log_msg;
-  while (PmsgRead(&logger_list, &transp, &log_msg) > 0) {
+  while (PmsgRead(&logger_list, &log_msg) > 0) {
     const char* cp;
     size_t hdr_size = log_msg.entry.hdr_size;
 
@@ -421,7 +375,7 @@
     }
     list_add_head(node, &content->node);
   }
-  PmsgClose(&logger_list, &transp);
+  PmsgClose(&logger_list);
 
   /* Progress through all the collected files */
   list_for_each_safe(node, n, &name_list) {
diff --git a/liblog/pmsg_reader.h b/liblog/pmsg_reader.h
new file mode 100644
index 0000000..53746d8
--- /dev/null
+++ b/liblog/pmsg_reader.h
@@ -0,0 +1,29 @@
+/*
+ * Copyright 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 <unistd.h>
+
+#include "log/log_read.h"
+#include "log_portability.h"
+
+__BEGIN_DECLS
+
+int PmsgRead(struct logger_list* logger_list, struct log_msg* log_msg);
+void PmsgClose(struct logger_list* logger_list);
+
+__END_DECLS
diff --git a/liblog/tests/liblog_benchmark.cpp b/liblog/tests/liblog_benchmark.cpp
index 56892a2..39ac7a5 100644
--- a/liblog/tests/liblog_benchmark.cpp
+++ b/liblog/tests/liblog_benchmark.cpp
@@ -913,7 +913,7 @@
 }
 BENCHMARK(BM_lookupEventTagNum);
 
-// Must be functionally identical to liblog internal __send_log_msg.
+// Must be functionally identical to liblog internal SendLogdControlMessage()
 static void send_to_control(char* buf, size_t len) {
   int sock =
       socket_local_client("logd", ANDROID_SOCKET_NAMESPACE_RESERVED, SOCK_STREAM | SOCK_CLOEXEC);
diff --git a/libunwindstack/Android.bp b/libunwindstack/Android.bp
index 2573b1c..512c962 100644
--- a/libunwindstack/Android.bp
+++ b/libunwindstack/Android.bp
@@ -77,6 +77,7 @@
     ],
 
     cflags: [
+        "-DDEXFILE_SUPPORT",
         "-Wexit-time-destructors",
     ],
 
@@ -89,20 +90,18 @@
             ],
         },
         vendor: {
-            cflags: ["-DNO_LIBDEXFILE_SUPPORT"],
+            cflags: ["-UDEXFILE_SUPPORT"],
             exclude_srcs: [
                 "DexFile.cpp",
-                "DexFiles.cpp",
             ],
             exclude_shared_libs: [
                 "libdexfile_support",
             ],
         },
         recovery: {
-            cflags: ["-DNO_LIBDEXFILE_SUPPORT"],
+            cflags: ["-UDEXFILE_SUPPORT"],
             exclude_srcs: [
                 "DexFile.cpp",
-                "DexFiles.cpp",
             ],
             exclude_shared_libs: [
                 "libdexfile_support",
diff --git a/libunwindstack/DexFiles.cpp b/libunwindstack/DexFiles.cpp
index 63a77e5..2057fad 100644
--- a/libunwindstack/DexFiles.cpp
+++ b/libunwindstack/DexFiles.cpp
@@ -27,10 +27,21 @@
 #include <unwindstack/Maps.h>
 #include <unwindstack/Memory.h>
 
+#if defined(DEXFILE_SUPPORT)
 #include "DexFile.h"
+#endif
 
 namespace unwindstack {
 
+#if !defined(DEXFILE_SUPPORT)
+// Empty class definition.
+class DexFile {
+ public:
+  DexFile() = default;
+  virtual ~DexFile() = default;
+};
+#endif
+
 struct DEXFileEntry32 {
   uint32_t next;
   uint32_t prev;
@@ -128,6 +139,7 @@
   FindAndReadVariable(maps, "__dex_debug_descriptor");
 }
 
+#if defined(DEXFILE_SUPPORT)
 DexFile* DexFiles::GetDexFile(uint64_t dex_file_offset, MapInfo* info) {
   // Lock while processing the data.
   DexFile* dex_file;
@@ -141,6 +153,11 @@
   }
   return dex_file;
 }
+#else
+DexFile* DexFiles::GetDexFile(uint64_t, MapInfo*) {
+  return nullptr;
+}
+#endif
 
 bool DexFiles::GetAddr(size_t index, uint64_t* addr) {
   if (index < addrs_.size()) {
@@ -154,6 +171,7 @@
   return false;
 }
 
+#if defined(DEXFILE_SUPPORT)
 void DexFiles::GetMethodInformation(Maps* maps, MapInfo* info, uint64_t dex_pc,
                                     std::string* method_name, uint64_t* method_offset) {
   std::lock_guard<std::mutex> guard(lock_);
@@ -175,5 +193,8 @@
     }
   }
 }
+#else
+void DexFiles::GetMethodInformation(Maps*, MapInfo*, uint64_t, std::string*, uint64_t*) {}
+#endif
 
 }  // namespace unwindstack
diff --git a/libunwindstack/RegsArm64.cpp b/libunwindstack/RegsArm64.cpp
index e9787aa..2e8af20 100644
--- a/libunwindstack/RegsArm64.cpp
+++ b/libunwindstack/RegsArm64.cpp
@@ -103,6 +103,7 @@
   fn("sp", regs_[ARM64_REG_SP]);
   fn("lr", regs_[ARM64_REG_LR]);
   fn("pc", regs_[ARM64_REG_PC]);
+  fn("pst", regs_[ARM64_REG_PSTATE]);
 }
 
 Regs* RegsArm64::Read(void* remote_data) {
@@ -113,6 +114,7 @@
   uint64_t* reg_data = reinterpret_cast<uint64_t*>(regs->RawData());
   reg_data[ARM64_REG_PC] = user->pc;
   reg_data[ARM64_REG_SP] = user->sp;
+  reg_data[ARM64_REG_PSTATE] = user->pstate;
   return regs;
 }
 
diff --git a/libunwindstack/Unwinder.cpp b/libunwindstack/Unwinder.cpp
index 0b9b85c..1bb0319 100644
--- a/libunwindstack/Unwinder.cpp
+++ b/libunwindstack/Unwinder.cpp
@@ -34,9 +34,7 @@
 #include <unwindstack/Memory.h>
 #include <unwindstack/Unwinder.h>
 
-#if !defined(NO_LIBDEXFILE_SUPPORT)
 #include <unwindstack/DexFiles.h>
-#endif
 
 // Use the demangler from libc++.
 extern "C" char* __cxa_demangle(const char*, char*, size_t*, int* status);
@@ -84,7 +82,7 @@
     return;
   }
 
-#if !defined(NO_LIBDEXFILE_SUPPORT)
+#if defined(DEXFILE_SUPPORT)
   if (dex_files_ == nullptr) {
     return;
   }
@@ -367,12 +365,10 @@
   jit_debug_ = jit_debug;
 }
 
-#if !defined(NO_LIBDEXFILE_SUPPORT)
 void Unwinder::SetDexFiles(DexFiles* dex_files, ArchEnum arch) {
   dex_files->SetArch(arch);
   dex_files_ = dex_files;
 }
-#endif
 
 bool UnwinderFromPid::Init(ArchEnum arch) {
   if (pid_ == getpid()) {
@@ -390,7 +386,7 @@
   jit_debug_ptr_.reset(new JitDebug(process_memory_));
   jit_debug_ = jit_debug_ptr_.get();
   SetJitDebug(jit_debug_, arch);
-#if !defined(NO_LIBDEXFILE_SUPPORT)
+#if defined(DEXFILE_SUPPORT)
   dex_files_ptr_.reset(new DexFiles(process_memory_));
   dex_files_ = dex_files_ptr_.get();
   SetDexFiles(dex_files_, arch);
diff --git a/libunwindstack/include/unwindstack/MachineArm64.h b/libunwindstack/include/unwindstack/MachineArm64.h
index e8b778b..e953335 100644
--- a/libunwindstack/include/unwindstack/MachineArm64.h
+++ b/libunwindstack/include/unwindstack/MachineArm64.h
@@ -55,6 +55,7 @@
   ARM64_REG_R30,
   ARM64_REG_R31,
   ARM64_REG_PC,
+  ARM64_REG_PSTATE,
   ARM64_REG_LAST,
 
   ARM64_REG_SP = ARM64_REG_R31,
diff --git a/libunwindstack/include/unwindstack/Unwinder.h b/libunwindstack/include/unwindstack/Unwinder.h
index 11ad9de..67762c0 100644
--- a/libunwindstack/include/unwindstack/Unwinder.h
+++ b/libunwindstack/include/unwindstack/Unwinder.h
@@ -107,9 +107,7 @@
 
   void SetDisplayBuildID(bool display_build_id) { display_build_id_ = display_build_id; }
 
-#if !defined(NO_LIBDEXFILE_SUPPORT)
   void SetDexFiles(DexFiles* dex_files, ArchEnum arch);
-#endif
 
   bool elf_from_memory_not_file() { return elf_from_memory_not_file_; }
 
@@ -128,9 +126,7 @@
   std::vector<FrameData> frames_;
   std::shared_ptr<Memory> process_memory_;
   JitDebug* jit_debug_ = nullptr;
-#if !defined(NO_LIBDEXFILE_SUPPORT)
   DexFiles* dex_files_ = nullptr;
-#endif
   bool resolve_names_ = true;
   bool embedded_soname_ = true;
   bool display_build_id_ = false;
@@ -151,9 +147,7 @@
   pid_t pid_;
   std::unique_ptr<Maps> maps_ptr_;
   std::unique_ptr<JitDebug> jit_debug_ptr_;
-#if !defined(NO_LIBDEXFILE_SUPPORT)
   std::unique_ptr<DexFiles> dex_files_ptr_;
-#endif
 };
 
 }  // namespace unwindstack
diff --git a/libunwindstack/tests/RegsIterateTest.cpp b/libunwindstack/tests/RegsIterateTest.cpp
index 7e36953..bc95851 100644
--- a/libunwindstack/tests/RegsIterateTest.cpp
+++ b/libunwindstack/tests/RegsIterateTest.cpp
@@ -114,6 +114,7 @@
   result.push_back({"sp", ARM64_REG_SP});
   result.push_back({"lr", ARM64_REG_LR});
   result.push_back({"pc", ARM64_REG_PC});
+  result.push_back({"pst", ARM64_REG_PSTATE});
   return result;
 }
 
diff --git a/libutils/Android.bp b/libutils/Android.bp
index 98921be..efa4c41 100644
--- a/libutils/Android.bp
+++ b/libutils/Android.bp
@@ -125,6 +125,7 @@
     native_bridge_supported: true,
 
     srcs: [
+        "Errors.cpp",
         "FileMap.cpp",
         "JenkinsHash.cpp",
         "NativeHandle.cpp",
diff --git a/libutils/Errors.cpp b/libutils/Errors.cpp
new file mode 100644
index 0000000..2dfd138
--- /dev/null
+++ b/libutils/Errors.cpp
@@ -0,0 +1,51 @@
+/*
+ * 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 <utils/Errors.h>
+
+namespace android {
+
+std::string statusToString(status_t s) {
+#define STATUS_CASE(STATUS) \
+    case STATUS:            \
+        return #STATUS
+
+    switch (s) {
+        STATUS_CASE(OK);
+        STATUS_CASE(UNKNOWN_ERROR);
+        STATUS_CASE(NO_MEMORY);
+        STATUS_CASE(INVALID_OPERATION);
+        STATUS_CASE(BAD_VALUE);
+        STATUS_CASE(BAD_TYPE);
+        STATUS_CASE(NAME_NOT_FOUND);
+        STATUS_CASE(PERMISSION_DENIED);
+        STATUS_CASE(NO_INIT);
+        STATUS_CASE(ALREADY_EXISTS);
+        STATUS_CASE(DEAD_OBJECT);
+        STATUS_CASE(FAILED_TRANSACTION);
+        STATUS_CASE(BAD_INDEX);
+        STATUS_CASE(NOT_ENOUGH_DATA);
+        STATUS_CASE(WOULD_BLOCK);
+        STATUS_CASE(TIMED_OUT);
+        STATUS_CASE(UNKNOWN_TRANSACTION);
+        STATUS_CASE(FDS_NOT_ALLOWED);
+        STATUS_CASE(UNEXPECTED_NULL);
+#undef STATUS_CASE
+    }
+
+    return std::to_string(s) + ' ' + strerror(-s);
+}
+
+}  // namespace android
diff --git a/libutils/include/utils/Errors.h b/libutils/include/utils/Errors.h
index 1e03677..d14d223 100644
--- a/libutils/include/utils/Errors.h
+++ b/libutils/include/utils/Errors.h
@@ -19,6 +19,7 @@
 #include <errno.h>
 #include <stdint.h>
 #include <sys/types.h>
+#include <string>
 
 namespace android {
 
@@ -72,6 +73,9 @@
     UNEXPECTED_NULL     = (UNKNOWN_ERROR + 8),
 };
 
+// Human readable name of error
+std::string statusToString(status_t status);
+
 // Restore define; enumeration is in "android" namespace, so the value defined
 // there won't work for Win32 code in a different namespace.
 #ifdef _WIN32
diff --git a/libziparchive/unzip.cpp b/libziparchive/unzip.cpp
index 56f594a..11b575e 100644
--- a/libziparchive/unzip.cpp
+++ b/libziparchive/unzip.cpp
@@ -448,6 +448,7 @@
 
   static const struct option opts[] = {
       {"help", no_argument, 0, 'h'},
+      {},
   };
 
   if (role == kUnzip) {
diff --git a/logcat/logcat.cpp b/logcat/logcat.cpp
index 70ccb80..2d14bf3 100644
--- a/logcat/logcat.cpp
+++ b/logcat/logcat.cpp
@@ -969,6 +969,16 @@
         }
     }
 
+    if (mode & ANDROID_LOG_PSTORE) {
+        if (clearLog) {
+            unlink("/sys/fs/pstore/pmsg-ramoops-0");
+            return EXIT_SUCCESS;
+        }
+        if (setLogSize || getLogSize || printStatistics || getPruneList || setPruneList) {
+            LogcatPanic(HELP_TRUE, "-L is incompatible with -g/-G, -S, and -p/-P");
+        }
+    }
+
     std::unique_ptr<logger_list, decltype(&android_logger_list_free)> logger_list{
             nullptr, &android_logger_list_free};
     if (tail_time != log_time::EPOCH) {
diff --git a/logd/LogBuffer.cpp b/logd/LogBuffer.cpp
index ba05a06..834b20b 100644
--- a/logd/LogBuffer.cpp
+++ b/logd/LogBuffer.cpp
@@ -638,6 +638,8 @@
     if (stats.sizes(id) > (2 * log_buffer_size(id))) {  // +100%
         // A misbehaving or slow reader has its connection
         // dropped if we hit too much memory pressure.
+        android::prdebug("Kicking blocked reader, pid %d, from LogBuffer::kickMe()\n",
+                         me->mClient->getPid());
         me->release_Locked();
     } else if (me->mTimeout.tv_sec || me->mTimeout.tv_nsec) {
         // Allow a blocked WRAP timeout reader to
@@ -645,6 +647,9 @@
         me->triggerReader_Locked();
     } else {
         // tell slow reader to skip entries to catch up
+        android::prdebug(
+                "Skipping %lu entries from slow reader, pid %d, from LogBuffer::kickMe()\n",
+                pruneRows, me->mClient->getPid());
         me->triggerSkip_Locked(id, pruneRows);
     }
 }
@@ -1051,6 +1056,9 @@
                     LogTimeEntry* entry = times->get();
                     // Killer punch
                     if (entry->isWatching(id)) {
+                        android::prdebug(
+                                "Kicking blocked reader, pid %d, from LogBuffer::clear()\n",
+                                entry->mClient->getPid());
                         entry->release_Locked();
                     }
                     times++;
diff --git a/property_service/libpropertyinfoserializer/property_info_serializer_test.cpp b/property_service/libpropertyinfoserializer/property_info_serializer_test.cpp
index 33da1f1..f4a846f 100644
--- a/property_service/libpropertyinfoserializer/property_info_serializer_test.cpp
+++ b/property_service/libpropertyinfoserializer/property_info_serializer_test.cpp
@@ -375,9 +375,11 @@
       {"audio_hal.period_size", "u:object_r:default_prop:s0"},
       {"bluetooth.enable_timeout_ms", "u:object_r:bluetooth_prop:s0"},
       {"dalvik.vm.appimageformat", "u:object_r:dalvik_prop:s0"},
+      {"dalvik.vm.boot-dex2oat-cpu-set", "u:object_r:dalvik_prop:s0"},
       {"dalvik.vm.boot-dex2oat-threads", "u:object_r:dalvik_prop:s0"},
       {"dalvik.vm.dex2oat-Xms", "u:object_r:dalvik_prop:s0"},
       {"dalvik.vm.dex2oat-Xmx", "u:object_r:dalvik_prop:s0"},
+      {"dalvik.vm.dex2oat-cpu-set", "u:object_r:dalvik_prop:s0"},
       {"dalvik.vm.dex2oat-threads", "u:object_r:dalvik_prop:s0"},
       {"dalvik.vm.dexopt.secondary", "u:object_r:dalvik_prop:s0"},
       {"dalvik.vm.heapgrowthlimit", "u:object_r:dalvik_prop:s0"},
@@ -388,6 +390,7 @@
       {"dalvik.vm.heaptargetutilization", "u:object_r:dalvik_prop:s0"},
       {"dalvik.vm.image-dex2oat-Xms", "u:object_r:dalvik_prop:s0"},
       {"dalvik.vm.image-dex2oat-Xmx", "u:object_r:dalvik_prop:s0"},
+      {"dalvik.vm.image-dex2oat-cpu-set", "u:object_r:dalvik_prop:s0"},
       {"dalvik.vm.image-dex2oat-threads", "u:object_r:dalvik_prop:s0"},
       {"dalvik.vm.isa.arm.features", "u:object_r:dalvik_prop:s0"},
       {"dalvik.vm.isa.arm.variant", "u:object_r:dalvik_prop:s0"},