diff --git a/adb/client/adb_install.cpp b/adb/client/adb_install.cpp
index 7f37c45..079a975 100644
--- a/adb/client/adb_install.cpp
+++ b/adb/client/adb_install.cpp
@@ -226,18 +226,8 @@
 
 static int install_app_legacy(int argc, const char** argv, bool use_fastdeploy,
                               bool use_localagent) {
-    static const char* const DATA_DEST = "/data/local/tmp/%s";
-    static const char* const SD_DEST = "/sdcard/tmp/%s";
-    const char* where = DATA_DEST;
-
     printf("Performing Push Install\n");
 
-    for (int i = 1; i < argc; i++) {
-        if (!strcmp(argv[i], "-s")) {
-            where = SD_DEST;
-        }
-    }
-
     // Find last APK argument.
     // All other arguments passed through verbatim.
     int last_apk = -1;
@@ -256,7 +246,7 @@
     int result = -1;
     std::vector<const char*> apk_file = {argv[last_apk]};
     std::string apk_dest =
-            android::base::StringPrintf(where, android::base::Basename(argv[last_apk]).c_str());
+            "/data/local/tmp/" + android::base::Basename(argv[last_apk]);
 
     if (use_fastdeploy == true) {
         TemporaryFile metadataTmpFile;
diff --git a/adb/client/commandline.cpp b/adb/client/commandline.cpp
index c11052d..95e66ae 100644
--- a/adb/client/commandline.cpp
+++ b/adb/client/commandline.cpp
@@ -146,10 +146,8 @@
         " install [-lrtsdg] [--instant] PACKAGE\n"
         " install-multiple [-lrtsdpg] [--instant] PACKAGE...\n"
         "     push package(s) to the device and install them\n"
-        "     -l: forward lock application\n"
         "     -r: replace existing application\n"
         "     -t: allow test packages\n"
-        "     -s: install application on sdcard\n"
         "     -d: allow version code downgrade (debuggable packages only)\n"
         "     -p: partial application install (install-multiple only)\n"
         "     -g: grant all runtime permissions\n"
diff --git a/adb/client/fastdeploy.cpp b/adb/client/fastdeploy.cpp
index 45f3cca..e82f15a 100644
--- a/adb/client/fastdeploy.cpp
+++ b/adb/client/fastdeploy.cpp
@@ -228,11 +228,12 @@
             android::base::StringPrintf(kAgentExtractCommandPattern, packageName.c_str());
 
     std::vector<char> extractErrorBuffer;
-    int statusCode;
-    DeployAgentFileCallback cb(outputFp, &extractErrorBuffer, &statusCode);
+    DeployAgentFileCallback cb(outputFp, &extractErrorBuffer);
     int returnCode = send_shell_command(extractCommand, false, &cb);
     if (returnCode != 0) {
-        error_exit("Executing %s returned %d", extractCommand.c_str(), returnCode);
+        fprintf(stderr, "Executing %s returned %d\n", extractCommand.c_str(), returnCode);
+        fprintf(stderr, "%*s\n", int(extractErrorBuffer.size()), extractErrorBuffer.data());
+        error_exit("Aborting");
     }
 }
 
diff --git a/adb/client/fastdeploycallbacks.cpp b/adb/client/fastdeploycallbacks.cpp
index 6c9a21f..23a0aca 100644
--- a/adb/client/fastdeploycallbacks.cpp
+++ b/adb/client/fastdeploycallbacks.cpp
@@ -35,8 +35,7 @@
 
 class DeployAgentBufferCallback : public StandardStreamsCallbackInterface {
   public:
-    DeployAgentBufferCallback(std::vector<char>* outBuffer, std::vector<char>* errBuffer,
-                              int* statusCode);
+    DeployAgentBufferCallback(std::vector<char>* outBuffer, std::vector<char>* errBuffer);
 
     virtual void OnStdout(const char* buffer, int length);
     virtual void OnStderr(const char* buffer, int length);
@@ -45,27 +44,17 @@
   private:
     std::vector<char>* mpOutBuffer;
     std::vector<char>* mpErrBuffer;
-    int* mpStatusCode;
 };
 
 int capture_shell_command(const char* command, std::vector<char>* outBuffer,
                           std::vector<char>* errBuffer) {
-    int statusCode;
-    DeployAgentBufferCallback cb(outBuffer, errBuffer, &statusCode);
-    int ret = send_shell_command(command, false, &cb);
-
-    if (ret == 0) {
-        return statusCode;
-    } else {
-        return ret;
-    }
+    DeployAgentBufferCallback cb(outBuffer, errBuffer);
+    return send_shell_command(command, false, &cb);
 }
 
-DeployAgentFileCallback::DeployAgentFileCallback(FILE* outputFile, std::vector<char>* errBuffer,
-                                                 int* statusCode) {
+DeployAgentFileCallback::DeployAgentFileCallback(FILE* outputFile, std::vector<char>* errBuffer) {
     mpOutFile = outputFile;
     mpErrBuffer = errBuffer;
-    mpStatusCode = statusCode;
     mBytesWritten = 0;
 }
 
@@ -84,10 +73,7 @@
 }
 
 int DeployAgentFileCallback::Done(int status) {
-    if (mpStatusCode != NULL) {
-        *mpStatusCode = status;
-    }
-    return 0;
+    return status;
 }
 
 int DeployAgentFileCallback::getBytesWritten() {
@@ -95,11 +81,9 @@
 }
 
 DeployAgentBufferCallback::DeployAgentBufferCallback(std::vector<char>* outBuffer,
-                                                     std::vector<char>* errBuffer,
-                                                     int* statusCode) {
+                                                     std::vector<char>* errBuffer) {
     mpOutBuffer = outBuffer;
     mpErrBuffer = errBuffer;
-    mpStatusCode = statusCode;
 }
 
 void DeployAgentBufferCallback::OnStdout(const char* buffer, int length) {
@@ -111,8 +95,5 @@
 }
 
 int DeployAgentBufferCallback::Done(int status) {
-    if (mpStatusCode != NULL) {
-        *mpStatusCode = status;
-    }
-    return 0;
+    return status;
 }
diff --git a/adb/client/fastdeploycallbacks.h b/adb/client/fastdeploycallbacks.h
index b428b50..7e049c5 100644
--- a/adb/client/fastdeploycallbacks.h
+++ b/adb/client/fastdeploycallbacks.h
@@ -21,7 +21,7 @@
 
 class DeployAgentFileCallback : public StandardStreamsCallbackInterface {
   public:
-    DeployAgentFileCallback(FILE* outputFile, std::vector<char>* errBuffer, int* statusCode);
+    DeployAgentFileCallback(FILE* outputFile, std::vector<char>* errBuffer);
 
     virtual void OnStdout(const char* buffer, int length);
     virtual void OnStderr(const char* buffer, int length);
@@ -33,7 +33,6 @@
     FILE* mpOutFile;
     std::vector<char>* mpErrBuffer;
     int mBytesWritten;
-    int* mpStatusCode;
 };
 
 int capture_shell_command(const char* command, std::vector<char>* outBuffer,
diff --git a/base/file.cpp b/base/file.cpp
index d5bb7fe..2f4a517 100644
--- a/base/file.cpp
+++ b/base/file.cpp
@@ -22,6 +22,7 @@
 #include <libgen.h>
 #include <stdio.h>
 #include <stdlib.h>
+#include <string.h>
 #include <sys/stat.h>
 #include <sys/types.h>
 #include <unistd.h>
diff --git a/base/logging.cpp b/base/logging.cpp
index bd09069..f89168c 100644
--- a/base/logging.cpp
+++ b/base/logging.cpp
@@ -417,6 +417,14 @@
   }
   std::string msg(data_->ToString());
 
+  if (data_->GetSeverity() == FATAL) {
+#ifdef __ANDROID__
+    // Set the bionic abort message early to avoid liblog doing it
+    // with the individual lines, so that we get the whole message.
+    android_set_abort_message(msg.c_str());
+#endif
+  }
+
   {
     // Do the actual logging with the lock held.
     std::lock_guard<std::mutex> lock(LoggingLock());
diff --git a/fastboot/fastboot.cpp b/fastboot/fastboot.cpp
index fee0857..b717aef 100644
--- a/fastboot/fastboot.cpp
+++ b/fastboot/fastboot.cpp
@@ -1541,7 +1541,7 @@
         return false;
     }
     auto path = find_item_given_name("super_empty.img");
-    if (path.empty()) {
+    if (path.empty() || access(path.c_str(), R_OK)) {
         return false;
     }
     auto metadata = android::fs_mgr::ReadFromImageFile(path);
diff --git a/fs_mgr/README.overlayfs.md b/fs_mgr/README.overlayfs.md
index 2d42d6c..fbb5f5d 100644
--- a/fs_mgr/README.overlayfs.md
+++ b/fs_mgr/README.overlayfs.md
@@ -89,6 +89,18 @@
   if higher than 4.6.
 - *adb enable-verity* will free up overlayfs and as a bonus the
   device will be reverted pristine to before any content was updated.
+  Update engine does not take advantage of this, will perform a full OTA.
+- Update engine will not run if *fs_mgr_overlayfs_is_setup*() reports
+  true as adb remount overrides are incompatable with an OTA for
+  multiple reasons.
+  NB: This is not a problem for fastbootd or recovery as overrides are
+  disabled for those special boot scenarios.
+- For implementation simplicity on retrofit dynamic partition devices,
+  take the whole alternate super (eg: if "*a*" slot, then the whole of
+  "*system_b*").
+  Since landing a filesystem on the alternate super physical device
+  without differentiating if it is setup to support logical or physical,
+  the alternate slot metadata and previous content will be lost.
 - If dynamic partitions runs out of space, resizing a logical
   partition larger may fail because of the scratch partition.
   If this happens, either fastboot flashall or adb enable-verity can
diff --git a/fs_mgr/fs_mgr.cpp b/fs_mgr/fs_mgr.cpp
index 70a54d9..60ce452 100644
--- a/fs_mgr/fs_mgr.cpp
+++ b/fs_mgr/fs_mgr.cpp
@@ -1005,8 +1005,9 @@
     for (i = 0; i < fstab->num_entries; i++) {
         /* Don't mount entries that are managed by vold or not for the mount mode*/
         if ((fstab->recs[i].fs_mgr_flags & (MF_VOLDMANAGED | MF_RECOVERYONLY)) ||
-             ((mount_mode == MOUNT_MODE_LATE) && !fs_mgr_is_latemount(&fstab->recs[i])) ||
-             ((mount_mode == MOUNT_MODE_EARLY) && fs_mgr_is_latemount(&fstab->recs[i]))) {
+            ((mount_mode == MOUNT_MODE_LATE) && !fs_mgr_is_latemount(&fstab->recs[i])) ||
+            ((mount_mode == MOUNT_MODE_EARLY) && fs_mgr_is_latemount(&fstab->recs[i])) ||
+            fs_mgr_is_first_stage_mount(&fstab->recs[i])) {
             continue;
         }
 
diff --git a/fs_mgr/fs_mgr_fstab.cpp b/fs_mgr/fs_mgr_fstab.cpp
index 31b0944..0fde22e 100644
--- a/fs_mgr/fs_mgr_fstab.cpp
+++ b/fs_mgr/fs_mgr_fstab.cpp
@@ -57,7 +57,7 @@
 
 struct flag_list {
     const char *name;
-    int flag;
+    unsigned int flag;
 };
 
 static struct flag_list mount_flags[] = {
@@ -102,6 +102,7 @@
         {"formattable", MF_FORMATTABLE},
         {"slotselect", MF_SLOTSELECT},
         {"nofail", MF_NOFAIL},
+        {"first_stage_mount", MF_FIRST_STAGE_MOUNT},
         {"latemount", MF_LATEMOUNT},
         {"reservedsize=", MF_RESERVEDSIZE},
         {"quota", MF_QUOTA},
@@ -998,6 +999,10 @@
     return fstab->fs_mgr_flags & MF_NOFAIL;
 }
 
+int fs_mgr_is_first_stage_mount(const struct fstab_rec* fstab) {
+    return fstab->fs_mgr_flags & MF_FIRST_STAGE_MOUNT;
+}
+
 int fs_mgr_is_latemount(const struct fstab_rec* fstab) {
     return fstab->fs_mgr_flags & MF_LATEMOUNT;
 }
diff --git a/fs_mgr/fs_mgr_overlayfs.cpp b/fs_mgr/fs_mgr_overlayfs.cpp
index 57e984d..649c8bf 100644
--- a/fs_mgr/fs_mgr_overlayfs.cpp
+++ b/fs_mgr/fs_mgr_overlayfs.cpp
@@ -74,7 +74,7 @@
     return false;
 }
 
-bool fs_mgr_overlayfs_mount_all(const std::vector<const fstab_rec*>&) {
+bool fs_mgr_overlayfs_mount_all(const std::vector<fstab_rec*>&) {
     return false;
 }
 
@@ -82,7 +82,7 @@
     return {};
 }
 
-std::vector<std::string> fs_mgr_overlayfs_required_devices(const std::vector<const fstab_rec*>&) {
+std::vector<std::string> fs_mgr_overlayfs_required_devices(const std::vector<fstab_rec*>&) {
     return {};
 }
 
@@ -96,6 +96,10 @@
     return false;
 }
 
+bool fs_mgr_overlayfs_is_setup() {
+    return false;
+}
+
 #else  // ALLOW_ADBD_DISABLE_VERITY == 0
 
 namespace {
@@ -382,8 +386,10 @@
     return SlotNumberForSlotSuffix(fs_mgr_get_slot_suffix());
 }
 
+const auto kPhysicalDevice = "/dev/block/by-name/"s;
+
 std::string fs_mgr_overlayfs_super_device(uint32_t slot_number) {
-    return "/dev/block/by-name/" + fs_mgr_get_super_partition_name(slot_number);
+    return kPhysicalDevice + fs_mgr_get_super_partition_name(slot_number);
 }
 
 bool fs_mgr_overlayfs_has_logical(const fstab* fstab) {
@@ -641,19 +647,50 @@
 std::string fs_mgr_overlayfs_scratch_device() {
     if (!scratch_device_cache.empty()) return scratch_device_cache;
 
-    auto& dm = DeviceMapper::Instance();
-    const auto partition_name = android::base::Basename(kScratchMountPoint);
-    std::string path;
-    if (!dm.GetDmDevicePathByName(partition_name, &path)) return "";
+    // Is this a multiple super device (retrofit)?
+    auto slot_number = fs_mgr_overlayfs_slot_number();
+    auto super_device = fs_mgr_overlayfs_super_device(slot_number);
+    auto path = fs_mgr_overlayfs_super_device(slot_number == 0);
+    if (super_device == path) {
+        // Create from within single super device;
+        auto& dm = DeviceMapper::Instance();
+        const auto partition_name = android::base::Basename(kScratchMountPoint);
+        if (!dm.GetDmDevicePathByName(partition_name, &path)) return "";
+    }
     return scratch_device_cache = path;
 }
 
-// Create and mount kScratchMountPoint storage if we have logical partitions
-bool fs_mgr_overlayfs_setup_scratch(const fstab* fstab, bool* change) {
-    if (fs_mgr_overlayfs_already_mounted(kScratchMountPoint, false)) return true;
-    auto mnt_type = fs_mgr_overlayfs_scratch_mount_type();
-    auto scratch_device = fs_mgr_overlayfs_scratch_device();
-    auto partition_create = !fs_mgr_rw_access(scratch_device);
+bool fs_mgr_overlayfs_make_scratch(const std::string& scratch_device, const std::string& mnt_type) {
+    // Force mkfs by design for overlay support of adb remount, simplify and
+    // thus do not rely on fsck to correct problems that could creep in.
+    auto command = ""s;
+    if (mnt_type == "f2fs") {
+        command = kMkF2fs + " -w 4096 -f -d1 -l" + android::base::Basename(kScratchMountPoint);
+    } else if (mnt_type == "ext4") {
+        command = kMkExt4 + " -b 4096 -t ext4 -m 0 -O has_journal -M " + kScratchMountPoint;
+    } else {
+        errno = ESRCH;
+        LERROR << mnt_type << " has no mkfs cookbook";
+        return false;
+    }
+    command += " " + scratch_device;
+    auto ret = system(command.c_str());
+    if (ret) {
+        LERROR << "make " << mnt_type << " filesystem on " << scratch_device << " return=" << ret;
+        return false;
+    }
+    return true;
+}
+
+bool fs_mgr_overlayfs_create_scratch(const fstab* fstab, std::string* scratch_device,
+                                     bool* partition_exists, bool* change) {
+    *scratch_device = fs_mgr_overlayfs_scratch_device();
+    *partition_exists = fs_mgr_rw_access(*scratch_device);
+    auto partition_create = !*partition_exists;
+    // Do we need to create a logical "scratch" partition?
+    if (!partition_create && android::base::StartsWith(*scratch_device, kPhysicalDevice)) {
+        return true;
+    }
     auto slot_number = fs_mgr_overlayfs_slot_number();
     auto super_device = fs_mgr_overlayfs_super_device(slot_number);
     if (!fs_mgr_rw_access(super_device)) return false;
@@ -665,9 +702,9 @@
     }
     const auto partition_name = android::base::Basename(kScratchMountPoint);
     auto partition = builder->FindPartition(partition_name);
-    auto partition_exists = partition != nullptr;
+    *partition_exists = partition != nullptr;
     auto changed = false;
-    if (!partition_exists) {
+    if (!*partition_exists) {
         partition = builder->AddPartition(partition_name, LP_PARTITION_ATTR_NONE);
         if (!partition) {
             LERROR << "create " << partition_name;
@@ -703,7 +740,7 @@
                 }
                 if (!partition_create) DestroyLogicalPartition(partition_name, 10s);
                 changed = true;
-                partition_exists = false;
+                *partition_exists = false;
             }
         }
     }
@@ -720,39 +757,36 @@
 
     if (changed || partition_create) {
         if (!CreateLogicalPartition(super_device, slot_number, partition_name, true, 0s,
-                                    &scratch_device))
+                                    scratch_device))
             return false;
 
         if (change) *change = true;
     }
+    return true;
+}
 
+// Create and mount kScratchMountPoint storage if we have logical partitions
+bool fs_mgr_overlayfs_setup_scratch(const fstab* fstab, bool* change) {
+    if (fs_mgr_overlayfs_already_mounted(kScratchMountPoint, false)) return true;
+
+    std::string scratch_device;
+    bool partition_exists;
+    if (!fs_mgr_overlayfs_create_scratch(fstab, &scratch_device, &partition_exists, change)) {
+        return false;
+    }
+
+    // If the partition exists, assume first that it can be mounted.
+    auto mnt_type = fs_mgr_overlayfs_scratch_mount_type();
     if (partition_exists) {
         if (fs_mgr_overlayfs_mount_scratch(scratch_device, mnt_type)) {
             if (change) *change = true;
             return true;
         }
-        // partition existed, but was not initialized;
+        // partition existed, but was not initialized; fall through to make it.
         errno = 0;
     }
 
-    // Force mkfs by design for overlay support of adb remount, simplify and
-    // thus do not rely on fsck to correct problems that could creep in.
-    auto command = ""s;
-    if (mnt_type == "f2fs") {
-        command = kMkF2fs + " -w 4096 -f -d1 -l" + android::base::Basename(kScratchMountPoint);
-    } else if (mnt_type == "ext4") {
-        command = kMkExt4 + " -b 4096 -t ext4 -m 0 -O has_journal -M " + kScratchMountPoint;
-    } else {
-        errno = ESRCH;
-        LERROR << mnt_type << " has no mkfs cookbook";
-        return false;
-    }
-    command += " " + scratch_device;
-    auto ret = system(command.c_str());
-    if (ret) {
-        LERROR << "make " << mnt_type << " filesystem on " << scratch_device << " return=" << ret;
-        return false;
-    }
+    if (!fs_mgr_overlayfs_make_scratch(scratch_device, mnt_type)) return false;
 
     if (change) *change = true;
 
@@ -762,6 +796,7 @@
 bool fs_mgr_overlayfs_scratch_can_be_mounted(const std::string& scratch_device) {
     if (scratch_device.empty()) return false;
     if (fs_mgr_overlayfs_already_mounted(kScratchMountPoint, false)) return false;
+    if (android::base::StartsWith(scratch_device, kPhysicalDevice)) return true;
     if (fs_mgr_rw_access(scratch_device)) return true;
     auto slot_number = fs_mgr_overlayfs_slot_number();
     auto super_device = fs_mgr_overlayfs_super_device(slot_number);
@@ -805,7 +840,7 @@
     return ret;
 }
 
-bool fs_mgr_overlayfs_mount_all(const std::vector<const fstab_rec*>& fsrecs) {
+bool fs_mgr_overlayfs_mount_all(const std::vector<fstab_rec*>& fsrecs) {
     std::vector<fstab_rec> recs;
     for (const auto& rec : fsrecs) recs.push_back(*rec);
     fstab fstab = {static_cast<int>(fsrecs.size()), &recs[0]};
@@ -828,8 +863,7 @@
     return {};
 }
 
-std::vector<std::string> fs_mgr_overlayfs_required_devices(
-        const std::vector<const fstab_rec*>& fsrecs) {
+std::vector<std::string> fs_mgr_overlayfs_required_devices(const std::vector<fstab_rec*>& fsrecs) {
     std::vector<fstab_rec> recs;
     for (const auto& rec : fsrecs) recs.push_back(*rec);
     fstab fstab = {static_cast<int>(fsrecs.size()), &recs[0]};
@@ -924,6 +958,17 @@
     return ret;
 }
 
+bool fs_mgr_overlayfs_is_setup() {
+    if (fs_mgr_overlayfs_already_mounted(kScratchMountPoint, false)) return true;
+    std::unique_ptr<fstab, decltype(&fs_mgr_free_fstab)> fstab(fs_mgr_read_fstab_default(),
+                                                               fs_mgr_free_fstab);
+    if (fs_mgr_overlayfs_invalid(fstab.get())) return false;
+    for (const auto& mount_point : fs_mgr_candidate_list(fstab.get())) {
+        if (fs_mgr_overlayfs_already_mounted(mount_point)) return true;
+    }
+    return false;
+}
+
 #endif  // ALLOW_ADBD_DISABLE_VERITY != 0
 
 bool fs_mgr_has_shared_blocks(const std::string& mount_point, const std::string& dev) {
diff --git a/fs_mgr/fs_mgr_priv.h b/fs_mgr/fs_mgr_priv.h
index 84e4ce5..faef34b 100644
--- a/fs_mgr/fs_mgr_priv.h
+++ b/fs_mgr/fs_mgr_priv.h
@@ -118,6 +118,8 @@
 #define MF_LOGICAL        0x10000000
 #define MF_CHECKPOINT_BLK 0x20000000
 #define MF_CHECKPOINT_FS  0x40000000
+#define MF_FIRST_STAGE_MOUNT \
+                          0x80000000
 // clang-format on
 
 #define DM_BUF_SIZE 4096
diff --git a/fs_mgr/include/fs_mgr_overlayfs.h b/fs_mgr/include/fs_mgr_overlayfs.h
index deaf4cb..0dd9121 100644
--- a/fs_mgr/include/fs_mgr_overlayfs.h
+++ b/fs_mgr/include/fs_mgr_overlayfs.h
@@ -22,13 +22,13 @@
 #include <vector>
 
 bool fs_mgr_overlayfs_mount_all(fstab* fstab);
-bool fs_mgr_overlayfs_mount_all(const std::vector<const fstab_rec*>& fstab);
+bool fs_mgr_overlayfs_mount_all(const std::vector<fstab_rec*>& fstab);
 std::vector<std::string> fs_mgr_overlayfs_required_devices(fstab* fstab);
-std::vector<std::string> fs_mgr_overlayfs_required_devices(
-        const std::vector<const fstab_rec*>& fstab);
+std::vector<std::string> fs_mgr_overlayfs_required_devices(const std::vector<fstab_rec*>& fstab);
 bool fs_mgr_overlayfs_setup(const char* backing = nullptr, const char* mount_point = nullptr,
                             bool* change = nullptr);
 bool fs_mgr_overlayfs_teardown(const char* mount_point = nullptr, bool* change = nullptr);
+bool fs_mgr_overlayfs_is_setup();
 bool fs_mgr_has_shared_blocks(const std::string& mount_point, const std::string& dev);
 std::string fs_mgr_get_context(const std::string& mount_point);
 
diff --git a/fs_mgr/include_fstab/fstab/fstab.h b/fs_mgr/include_fstab/fstab/fstab.h
index 80bdb87..4706028 100644
--- a/fs_mgr/include_fstab/fstab/fstab.h
+++ b/fs_mgr/include_fstab/fstab/fstab.h
@@ -84,6 +84,7 @@
 int fs_mgr_is_formattable(const struct fstab_rec* fstab);
 int fs_mgr_is_slotselect(const struct fstab_rec* fstab);
 int fs_mgr_is_nofail(const struct fstab_rec* fstab);
+int fs_mgr_is_first_stage_mount(const struct fstab_rec* fstab);
 int fs_mgr_is_latemount(const struct fstab_rec* fstab);
 int fs_mgr_is_quota(const struct fstab_rec* fstab);
 int fs_mgr_is_logical(const struct fstab_rec* fstab);
diff --git a/fs_mgr/tests/adb-remount-test.sh b/fs_mgr/tests/adb-remount-test.sh
index c7c86eb..561debb 100755
--- a/fs_mgr/tests/adb-remount-test.sh
+++ b/fs_mgr/tests/adb-remount-test.sh
@@ -378,6 +378,11 @@
 M=`adb_sh cat /proc/mounts | sed -n 's@\([^ ]*\) /mnt/scratch \([^ ]*\) .*@\2 on \1@p'`
 [ -n "${M}" ] &&
   echo "${BLUE}[     INFO ]${NORMAL} scratch filesystem ${M}"
+uses_dynamic_scratch=true
+if [ "${M}" != "${M##*/dev/block/by-name/}" ]; then
+  uses_dynamic_scratch=false
+  scratch_partition="${M##*/dev/block/by-name/}"
+fi
 scratch_size=`adb_sh df -k /mnt/scratch </dev/null 2>/dev/null |
               while read device kblocks used available use mounted on; do
                 if [ "/mnt/scratch" = "\${mounted}" ]; then
@@ -453,16 +458,30 @@
   fastboot flash vendor ||
   ( fastboot reboot && false) ||
   die "fastboot flash vendor"
-# check ${scratch_partition} via fastboot
-fastboot_getvar partition-type:${scratch_partition} raw &&
-  fastboot_getvar has-slot:${scratch_partition} no &&
-  fastboot_getvar is-logical:${scratch_partition} yes ||
+fastboot_getvar partition-type:${scratch_partition} raw ||
   ( fastboot reboot && false) ||
   die "fastboot can not see ${scratch_partition} parameters"
-echo "${BLUE}[     INFO ]${NORMAL} expect fastboot erase ${scratch_partition} to fail" >&2
-fastboot erase ${scratch_partition} &&
-  ( fastboot reboot || true) &&
-  die "fastboot can erase ${scratch_partition}"
+if ${uses_dynamic_scratch}; then
+  # check ${scratch_partition} via fastboot
+  fastboot_getvar has-slot:${scratch_partition} no &&
+    fastboot_getvar is-logical:${scratch_partition} yes ||
+    ( fastboot reboot && false) ||
+    die "fastboot can not see ${scratch_partition} parameters"
+else
+  fastboot_getvar is-logical:${scratch_partition} no ||
+    ( fastboot reboot && false) ||
+    die "fastboot can not see ${scratch_partition} parameters"
+fi
+if ! ${uses_dynamic_scratch}; then
+  fastboot reboot-bootloader ||
+    die "Reboot into fastboot"
+fi
+if ${uses_dynamic_scratch}; then
+  echo "${BLUE}[     INFO ]${NORMAL} expect fastboot erase ${scratch_partition} to fail" >&2
+  fastboot erase ${scratch_partition} &&
+    ( fastboot reboot || true) &&
+    die "fastboot can erase ${scratch_partition}"
+fi
 echo "${BLUE}[     INFO ]${NORMAL} expect fastboot format ${scratch_partition} to fail" >&2
 fastboot format ${scratch_partition} &&
   ( fastboot reboot || true) &&
@@ -507,12 +526,13 @@
 
 echo "${GREEN}[ RUN      ]${NORMAL} test fastboot flash to ${scratch_partition}" >&2
 
-adb reboot-fastboot &&
-  dd if=/dev/zero of=/tmp/adb-remount-test.img bs=4096 count=16 2>/dev/null &&
+adb reboot-fastboot ||
+  die "Reboot into fastbootd"
+dd if=/dev/zero of=/tmp/adb-remount-test.img bs=4096 count=16 2>/dev/null &&
   fastboot_wait 2m ||
   ( rm /tmp/adb-remount-test.img && false) ||
   die "reboot into fastboot"
-fastboot flash ${scratch_partition} /tmp/adb-remount-test.img
+fastboot flash --force ${scratch_partition} /tmp/adb-remount-test.img
 err=${?}
 rm /tmp/adb-remount-test.img
 fastboot reboot ||
diff --git a/init/Android.bp b/init/Android.bp
index ea66ac6..e7b8516 100644
--- a/init/Android.bp
+++ b/init/Android.bp
@@ -19,6 +19,7 @@
     cpp_std: "experimental",
     sanitize: {
         misc_undefined: ["signed-integer-overflow"],
+        address: false,  // TODO(b/120561310): Fix ASAN to work without /proc mounted and re-enable.
     },
     cflags: [
         "-DLOG_UEVENTS=0",
diff --git a/init/Android.mk b/init/Android.mk
index 0e6ee0b..bdd0301 100644
--- a/init/Android.mk
+++ b/init/Android.mk
@@ -104,7 +104,6 @@
 LOCAL_REQUIRED_MODULES := \
    init_second_stage \
 
-LOCAL_POST_INSTALL_CMD := ln -sf /system/bin/init $(TARGET_ROOT_OUT)/init
 include $(BUILD_PHONY_PACKAGE)
 
 include $(CLEAR_VARS)
diff --git a/init/first_stage_mount.cpp b/init/first_stage_mount.cpp
index 2f7f79d..6ae1123 100644
--- a/init/first_stage_mount.cpp
+++ b/init/first_stage_mount.cpp
@@ -84,7 +84,7 @@
 
     bool need_dm_verity_;
 
-    std::unique_ptr<fstab, decltype(&fs_mgr_free_fstab)> device_tree_fstab_;
+    std::unique_ptr<fstab, decltype(&fs_mgr_free_fstab)> fstab_;
     std::string lp_metadata_partition_;
     std::vector<fstab_rec*> mount_fstab_recs_;
     std::set<std::string> required_devices_partition_names_;
@@ -132,15 +132,29 @@
 // Class Definitions
 // -----------------
 FirstStageMount::FirstStageMount()
-    : need_dm_verity_(false), device_tree_fstab_(fs_mgr_read_fstab_dt(), fs_mgr_free_fstab) {
-    if (device_tree_fstab_) {
-        // Stores device_tree_fstab_->recs[] into mount_fstab_recs_ (vector<fstab_rec*>)
-        // for easier manipulation later, e.g., range-base for loop.
-        for (int i = 0; i < device_tree_fstab_->num_entries; i++) {
-            mount_fstab_recs_.push_back(&device_tree_fstab_->recs[i]);
+    : need_dm_verity_(false),
+      fstab_(fs_mgr_read_fstab_dt(), fs_mgr_free_fstab),
+      uevent_listener_(16 * 1024 * 1024) {
+    // Stores fstab_->recs[] into mount_fstab_recs_ (vector<fstab_rec*>)
+    // for easier manipulation later, e.g., range-base for loop.
+    if (fstab_) {
+        // DT Fstab predated having a first_stage_mount fs_mgr flag, so if it exists, we use it.
+        for (int i = 0; i < fstab_->num_entries; i++) {
+            mount_fstab_recs_.push_back(&fstab_->recs[i]);
         }
     } else {
-        LOG(INFO) << "Failed to read fstab from device tree";
+        // Fstab found in first stage ramdisk, which should be a copy of the normal fstab.
+        // Mounts intended for first stage are explicitly flagged as such.
+        fstab_.reset(fs_mgr_read_fstab_default());
+        if (fstab_) {
+            for (int i = 0; i < fstab_->num_entries; i++) {
+                if (fs_mgr_is_first_stage_mount(&fstab_->recs[i])) {
+                    mount_fstab_recs_.push_back(&fstab_->recs[i]);
+                }
+            }
+        } else {
+            LOG(INFO) << "Failed to read fstab from device tree";
+        }
     }
 
     auto boot_devices = fs_mgr_get_boot_devices();
@@ -412,7 +426,7 @@
     }
 
     // heads up for instantiating required device(s) for overlayfs logic
-    const auto devices = fs_mgr_overlayfs_required_devices(device_tree_fstab_.get());
+    const auto devices = fs_mgr_overlayfs_required_devices(mount_fstab_recs_);
     for (auto const& device : devices) {
         if (android::base::StartsWith(device, "/dev/block/by-name/")) {
             required_devices_partition_names_.emplace(basename(device.c_str()));
@@ -424,7 +438,7 @@
         }
     }
 
-    fs_mgr_overlayfs_mount_all(device_tree_fstab_.get());
+    fs_mgr_overlayfs_mount_all(mount_fstab_recs_);
 
     return true;
 }
diff --git a/init/uevent_listener.cpp b/init/uevent_listener.cpp
index d6765b7..62cd2be 100644
--- a/init/uevent_listener.cpp
+++ b/init/uevent_listener.cpp
@@ -86,9 +86,8 @@
     }
 }
 
-UeventListener::UeventListener() {
-    // is 16MB enough? udev uses 128MB!
-    device_fd_.reset(uevent_open_socket(16 * 1024 * 1024, true));
+UeventListener::UeventListener(size_t uevent_socket_rcvbuf_size) {
+    device_fd_.reset(uevent_open_socket(uevent_socket_rcvbuf_size, true));
     if (device_fd_ == -1) {
         LOG(FATAL) << "Could not open uevent socket";
     }
diff --git a/init/uevent_listener.h b/init/uevent_listener.h
index 5b453fe..aea094e 100644
--- a/init/uevent_listener.h
+++ b/init/uevent_listener.h
@@ -41,7 +41,7 @@
 
 class UeventListener {
   public:
-    UeventListener();
+    UeventListener(size_t uevent_socket_rcvbuf_size);
 
     void RegenerateUevents(const ListenerCallback& callback) const;
     ListenerAction RegenerateUeventsForPath(const std::string& path,
diff --git a/init/ueventd.cpp b/init/ueventd.cpp
index 66491dd..7545d53 100644
--- a/init/ueventd.cpp
+++ b/init/ueventd.cpp
@@ -233,29 +233,26 @@
     SelabelInitialize();
 
     std::vector<std::unique_ptr<UeventHandler>> uevent_handlers;
-    UeventListener uevent_listener;
 
-    {
-        // Keep the current product name base configuration so we remain backwards compatible and
-        // allow it to override everything.
-        // TODO: cleanup platform ueventd.rc to remove vendor specific device node entries (b/34968103)
-        auto hardware = android::base::GetProperty("ro.hardware", "");
+    // Keep the current product name base configuration so we remain backwards compatible and
+    // allow it to override everything.
+    // TODO: cleanup platform ueventd.rc to remove vendor specific device node entries (b/34968103)
+    auto hardware = android::base::GetProperty("ro.hardware", "");
 
-        auto ueventd_configuration =
-                ParseConfig({"/ueventd.rc", "/vendor/ueventd.rc", "/odm/ueventd.rc",
-                             "/ueventd." + hardware + ".rc"});
+    auto ueventd_configuration = ParseConfig({"/ueventd.rc", "/vendor/ueventd.rc",
+                                              "/odm/ueventd.rc", "/ueventd." + hardware + ".rc"});
 
-        uevent_handlers.emplace_back(std::make_unique<DeviceHandler>(
-                std::move(ueventd_configuration.dev_permissions),
-                std::move(ueventd_configuration.sysfs_permissions),
-                std::move(ueventd_configuration.subsystems), fs_mgr_get_boot_devices(), true));
-        uevent_handlers.emplace_back(std::make_unique<FirmwareHandler>(
-                std::move(ueventd_configuration.firmware_directories)));
+    uevent_handlers.emplace_back(std::make_unique<DeviceHandler>(
+            std::move(ueventd_configuration.dev_permissions),
+            std::move(ueventd_configuration.sysfs_permissions),
+            std::move(ueventd_configuration.subsystems), fs_mgr_get_boot_devices(), true));
+    uevent_handlers.emplace_back(std::make_unique<FirmwareHandler>(
+            std::move(ueventd_configuration.firmware_directories)));
 
-        if (ueventd_configuration.enable_modalias_handling) {
-            uevent_handlers.emplace_back(std::make_unique<ModaliasHandler>());
-        }
+    if (ueventd_configuration.enable_modalias_handling) {
+        uevent_handlers.emplace_back(std::make_unique<ModaliasHandler>());
     }
+    UeventListener uevent_listener(ueventd_configuration.uevent_socket_rcvbuf_size);
 
     if (access(COLDBOOT_DONE, F_OK) != 0) {
         ColdBoot cold_boot(uevent_listener, uevent_handlers);
diff --git a/init/ueventd_parser.cpp b/init/ueventd_parser.cpp
index 677938e..aac3fe5 100644
--- a/init/ueventd_parser.cpp
+++ b/init/ueventd_parser.cpp
@@ -19,9 +19,13 @@
 #include <grp.h>
 #include <pwd.h>
 
+#include <android-base/parseint.h>
+
 #include "keyword_map.h"
 #include "parser.h"
 
+using android::base::ParseByteCount;
+
 namespace android {
 namespace init {
 
@@ -101,6 +105,22 @@
     return Success();
 }
 
+Result<Success> ParseUeventSocketRcvbufSizeLine(std::vector<std::string>&& args,
+                                                size_t* uevent_socket_rcvbuf_size) {
+    if (args.size() != 2) {
+        return Error() << "uevent_socket_rcvbuf_size lines take exactly one parameter";
+    }
+
+    size_t parsed_size;
+    if (!ParseByteCount(args[1], &parsed_size)) {
+        return Error() << "could not parse size '" << args[1] << "' for uevent_socket_rcvbuf_line";
+    }
+
+    *uevent_socket_rcvbuf_size = parsed_size;
+
+    return Success();
+}
+
 class SubsystemParser : public SectionParser {
   public:
     SubsystemParser(std::vector<Subsystem>* subsystems) : subsystems_(subsystems) {}
@@ -202,6 +222,9 @@
     parser.AddSingleLineParser("modalias_handling",
                                std::bind(ParseModaliasHandlingLine, _1,
                                          &ueventd_configuration.enable_modalias_handling));
+    parser.AddSingleLineParser("uevent_socket_rcvbuf_size",
+                               std::bind(ParseUeventSocketRcvbufSizeLine, _1,
+                                         &ueventd_configuration.uevent_socket_rcvbuf_size));
 
     for (const auto& config : configs) {
         parser.ParseConfig(config);
diff --git a/init/ueventd_parser.h b/init/ueventd_parser.h
index 7d30edf..d476dec 100644
--- a/init/ueventd_parser.h
+++ b/init/ueventd_parser.h
@@ -31,6 +31,7 @@
     std::vector<Permissions> dev_permissions;
     std::vector<std::string> firmware_directories;
     bool enable_modalias_handling = false;
+    size_t uevent_socket_rcvbuf_size = 0;
 };
 
 UeventdConfiguration ParseConfig(const std::vector<std::string>& configs);
diff --git a/init/ueventd_parser_test.cpp b/init/ueventd_parser_test.cpp
index c3af341..9c1cedf 100644
--- a/init/ueventd_parser_test.cpp
+++ b/init/ueventd_parser_test.cpp
@@ -138,6 +138,15 @@
     TestUeventdFile(ueventd_file, {{}, {}, {}, firmware_directories});
 }
 
+TEST(ueventd_parser, UeventSocketRcvbufSize) {
+    auto ueventd_file = R"(
+uevent_socket_rcvbuf_size 8k
+uevent_socket_rcvbuf_size 8M
+)";
+
+    TestUeventdFile(ueventd_file, {{}, {}, {}, {}, false, 8 * 1024 * 1024});
+}
+
 TEST(ueventd_parser, AllTogether) {
     auto ueventd_file = R"(
 
@@ -169,6 +178,8 @@
 /sys/devices/virtual/*/input   poll_delay  0660  root   input
 firmware_directories /more
 
+uevent_socket_rcvbuf_size 6M
+
 #ending comment
 )";
 
@@ -197,8 +208,10 @@
             "/more",
     };
 
-    TestUeventdFile(ueventd_file,
-                    {subsystems, sysfs_permissions, permissions, firmware_directories});
+    size_t uevent_socket_rcvbuf_size = 6 * 1024 * 1024;
+
+    TestUeventdFile(ueventd_file, {subsystems, sysfs_permissions, permissions, firmware_directories,
+                                   false, uevent_socket_rcvbuf_size});
 }
 
 // All of these lines are ill-formed, so test that there is 0 output.
@@ -213,6 +226,8 @@
 /sys/devices/platform/trusty.*      trusty_version        0440  baduidbad   log
 /sys/devices/platform/trusty.*      trusty_version        0440  root   baduidbad
 
+uevent_socket_rcvbuf_size blah
+
 subsystem #no name
 
 )";
diff --git a/libcutils/fs_config.cpp b/libcutils/fs_config.cpp
index ee52f5e..db59569 100644
--- a/libcutils/fs_config.cpp
+++ b/libcutils/fs_config.cpp
@@ -108,7 +108,9 @@
 // although the developer is advised to restrict the scope to the /vendor or
 // oem/ file-system since the intent is to provide support for customized
 // portions of a separate vendor.img or oem.img.  Has to remain open so that
-// customization can also land on /system/vendor, /system/oem or /system/odm.
+// customization can also land on /system/vendor, /system/oem, /system/odm,
+// /system/product or /system/product_services.
+//
 // We expect build-time checking or filtering when constructing the associated
 // fs_config_* files (see build/tools/fs_config/fs_config_generate.c)
 static const char ven_conf_dir[] = "/vendor/etc/fs_config_dirs";
@@ -117,11 +119,17 @@
 static const char oem_conf_file[] = "/oem/etc/fs_config_files";
 static const char odm_conf_dir[] = "/odm/etc/fs_config_dirs";
 static const char odm_conf_file[] = "/odm/etc/fs_config_files";
+static const char product_conf_dir[] = "/product/etc/fs_config_dirs";
+static const char product_conf_file[] = "/product/etc/fs_config_files";
+static const char product_services_conf_dir[] = "/product_services/etc/fs_config_dirs";
+static const char product_services_conf_file[] = "/product_services/etc/fs_config_files";
 static const char* conf[][2] = {
-    {sys_conf_file, sys_conf_dir},
-    {ven_conf_file, ven_conf_dir},
-    {oem_conf_file, oem_conf_dir},
-    {odm_conf_file, odm_conf_dir},
+        {sys_conf_file, sys_conf_dir},
+        {ven_conf_file, ven_conf_dir},
+        {oem_conf_file, oem_conf_dir},
+        {odm_conf_file, odm_conf_dir},
+        {product_conf_file, product_conf_dir},
+        {product_services_conf_file, product_services_conf_dir},
 };
 
 // Do not use android_files to grant Linux capabilities.  Use ambient capabilities in their
@@ -150,7 +158,11 @@
     { 00444, AID_ROOT,      AID_ROOT,      0, oem_conf_dir + 1 },
     { 00444, AID_ROOT,      AID_ROOT,      0, oem_conf_file + 1 },
     { 00600, AID_ROOT,      AID_ROOT,      0, "product/build.prop" },
+    { 00444, AID_ROOT,      AID_ROOT,      0, product_conf_dir + 1 },
+    { 00444, AID_ROOT,      AID_ROOT,      0, product_conf_file + 1 },
     { 00600, AID_ROOT,      AID_ROOT,      0, "product_services/build.prop" },
+    { 00444, AID_ROOT,      AID_ROOT,      0, product_services_conf_dir + 1 },
+    { 00444, AID_ROOT,      AID_ROOT,      0, product_services_conf_file + 1 },
     { 00750, AID_ROOT,      AID_SHELL,     0, "sbin/fs_mgr" },
     { 00755, AID_ROOT,      AID_SHELL,     0, "system/bin/crash_dump32" },
     { 00755, AID_ROOT,      AID_SHELL,     0, "system/bin/crash_dump64" },
@@ -236,10 +248,10 @@
     return fd;
 }
 
-// if path is "odm/<stuff>", "oem/<stuff>", "product/<stuff>" or
-// "vendor/<stuff>"
+// if path is "odm/<stuff>", "oem/<stuff>", "product/<stuff>",
+// "product_services/<stuff>" or "vendor/<stuff>"
 static bool is_partition(const char* path, size_t len) {
-    static const char* partitions[] = {"odm/", "oem/", "product/", "vendor/"};
+    static const char* partitions[] = {"odm/", "oem/", "product/", "product_services/", "vendor/"};
     for (size_t i = 0; i < (sizeof(partitions) / sizeof(partitions[0])); ++i) {
         size_t plen = strlen(partitions[i]);
         if (len <= plen) continue;
diff --git a/libmeminfo/Android.bp b/libmeminfo/Android.bp
index aab3743..3e191ad 100644
--- a/libmeminfo/Android.bp
+++ b/libmeminfo/Android.bp
@@ -54,6 +54,11 @@
     srcs: [
         "libmeminfo_test.cpp"
     ],
+
+    data: [
+        "testdata1/*",
+        "testdata2/*"
+    ],
 }
 
 cc_benchmark {
@@ -67,4 +72,8 @@
         "libmeminfo",
         "libprocinfo",
     ],
+
+    data: [
+        "testdata1/*",
+    ],
 }
diff --git a/libmeminfo/include/meminfo/meminfo.h b/libmeminfo/include/meminfo/meminfo.h
index c328648..809054b 100644
--- a/libmeminfo/include/meminfo/meminfo.h
+++ b/libmeminfo/include/meminfo/meminfo.h
@@ -31,6 +31,8 @@
     uint64_t pss;
     uint64_t uss;
 
+    uint64_t swap;
+
     uint64_t private_clean;
     uint64_t private_dirty;
     uint64_t shared_clean;
@@ -41,6 +43,7 @@
           rss(0),
           pss(0),
           uss(0),
+          swap(0),
           private_clean(0),
           private_dirty(0),
           shared_clean(0),
@@ -49,7 +52,7 @@
     ~MemUsage() = default;
 
     void clear() {
-        vss = rss = pss = uss = 0;
+        vss = rss = pss = uss = swap = 0;
         private_clean = private_dirty = shared_clean = shared_dirty = 0;
     }
 };
diff --git a/libmeminfo/include/meminfo/procmeminfo.h b/libmeminfo/include/meminfo/procmeminfo.h
index b37c56b..92375d3 100644
--- a/libmeminfo/include/meminfo/procmeminfo.h
+++ b/libmeminfo/include/meminfo/procmeminfo.h
@@ -29,13 +29,16 @@
 class ProcMemInfo final {
     // Per-process memory accounting
   public:
-    ProcMemInfo(pid_t pid, bool get_wss = false);
+    // Reset the working set accounting of the process via /proc/<pid>/clear_refs
+    static bool ResetWorkingSet(pid_t pid);
+
+    ProcMemInfo(pid_t pid, bool get_wss = false, uint64_t pgflags = 0, uint64_t pgflags_mask = 0);
 
     const std::vector<Vma>& Maps();
     const MemUsage& Usage();
     const MemUsage& Wss();
+    const std::vector<uint16_t>& SwapOffsets();
 
-    bool WssReset();
     ~ProcMemInfo() = default;
 
   private:
@@ -44,11 +47,14 @@
 
     pid_t pid_;
     bool get_wss_;
+    uint64_t pgflags_;
+    uint64_t pgflags_mask_;
 
     std::vector<Vma> maps_;
 
     MemUsage usage_;
     MemUsage wss_;
+    std::vector<uint16_t> swap_offsets_;
 };
 
 }  // namespace meminfo
diff --git a/libmeminfo/include/meminfo/sysmeminfo.h b/libmeminfo/include/meminfo/sysmeminfo.h
index f5e05bd..885be1d 100644
--- a/libmeminfo/include/meminfo/sysmeminfo.h
+++ b/libmeminfo/include/meminfo/sysmeminfo.h
@@ -28,6 +28,21 @@
 class SysMemInfo final {
     // System or Global memory accounting
   public:
+    static constexpr const char* kMemTotal = "MemTotal:";
+    static constexpr const char* kMemFree = "MemFree:";
+    static constexpr const char* kMemBuffers = "Buffers:";
+    static constexpr const char* kMemCached = "Cached:";
+    static constexpr const char* kMemShmem = "Shmem:";
+    static constexpr const char* kMemSlab = "Slab:";
+    static constexpr const char* kMemSReclaim = "SReclaimable:";
+    static constexpr const char* kMemSUnreclaim = "SUnreclaim:";
+    static constexpr const char* kMemSwapTotal = "SwapTotal:";
+    static constexpr const char* kMemSwapFree = "SwapFree:";
+    static constexpr const char* kMemMapped = "Mapped:";
+    static constexpr const char* kMemVmallocUsed = "VmallocUsed:";
+    static constexpr const char* kMemPageTables = "PageTables:";
+    static constexpr const char* kMemKernelStack = "KernelStack:";
+
     static const std::vector<std::string> kDefaultSysMemInfoTags;
 
     SysMemInfo() = default;
@@ -38,24 +53,25 @@
                      const std::string& path = "/proc/meminfo");
 
     // getters
-    uint64_t mem_total_kb() { return mem_in_kb_["MemTotal:"]; }
-    uint64_t mem_free_kb() { return mem_in_kb_["MemFree:"]; }
-    uint64_t mem_buffers_kb() { return mem_in_kb_["Buffers:"]; }
-    uint64_t mem_cached_kb() { return mem_in_kb_["Cached:"]; }
-    uint64_t mem_shmem_kb() { return mem_in_kb_["Shmem:"]; }
-    uint64_t mem_slab_kb() { return mem_in_kb_["Slab:"]; }
-    uint64_t mem_slab_reclailmable_kb() { return mem_in_kb_["SReclaimable:"]; }
-    uint64_t mem_slab_unreclaimable_kb() { return mem_in_kb_["SUnreclaim:"]; }
-    uint64_t mem_swap_kb() { return mem_in_kb_["SwapTotal:"]; }
-    uint64_t mem_free_swap_kb() { return mem_in_kb_["SwapFree:"]; }
-    uint64_t mem_zram_kb() { return mem_in_kb_["Zram:"]; }
-    uint64_t mem_mapped_kb() { return mem_in_kb_["Mapped:"]; }
-    uint64_t mem_vmalloc_used_kb() { return mem_in_kb_["VmallocUsed:"]; }
-    uint64_t mem_page_tables_kb() { return mem_in_kb_["PageTables:"]; }
-    uint64_t mem_kernel_stack_kb() { return mem_in_kb_["KernelStack:"]; }
+    uint64_t mem_total_kb() { return mem_in_kb_[kMemTotal]; }
+    uint64_t mem_free_kb() { return mem_in_kb_[kMemFree]; }
+    uint64_t mem_buffers_kb() { return mem_in_kb_[kMemBuffers]; }
+    uint64_t mem_cached_kb() { return mem_in_kb_[kMemCached]; }
+    uint64_t mem_shmem_kb() { return mem_in_kb_[kMemShmem]; }
+    uint64_t mem_slab_kb() { return mem_in_kb_[kMemSlab]; }
+    uint64_t mem_slab_reclailmable_kb() { return mem_in_kb_[kMemSReclaim]; }
+    uint64_t mem_slab_unreclaimable_kb() { return mem_in_kb_[kMemSUnreclaim]; }
+    uint64_t mem_swap_kb() { return mem_in_kb_[kMemSwapTotal]; }
+    uint64_t mem_swap_free_kb() { return mem_in_kb_[kMemSwapFree]; }
+    uint64_t mem_mapped_kb() { return mem_in_kb_[kMemMapped]; }
+    uint64_t mem_vmalloc_used_kb() { return mem_in_kb_[kMemVmallocUsed]; }
+    uint64_t mem_page_tables_kb() { return mem_in_kb_[kMemPageTables]; }
+    uint64_t mem_kernel_stack_kb() { return mem_in_kb_[kMemPageTables]; }
+    uint64_t mem_zram_kb(const std::string& zram_dev = "");
 
   private:
     std::map<std::string, uint64_t> mem_in_kb_;
+    bool MemZramDevice(const std::string& zram_dev, uint64_t* mem_zram_dev);
 };
 
 }  // namespace meminfo
diff --git a/libmeminfo/libmeminfo_benchmark.cpp b/libmeminfo/libmeminfo_benchmark.cpp
index e2239f0..1db0824 100644
--- a/libmeminfo/libmeminfo_benchmark.cpp
+++ b/libmeminfo/libmeminfo_benchmark.cpp
@@ -17,6 +17,8 @@
 #include <meminfo/sysmeminfo.h>
 
 #include <fcntl.h>
+#include <inttypes.h>
+#include <stdio.h>
 #include <sys/stat.h>
 #include <sys/types.h>
 
@@ -46,7 +48,7 @@
     MEMINFO_COUNT
 };
 
-void get_mem_info(uint64_t mem[], const char* file) {
+static void get_mem_info(uint64_t mem[], const char* file) {
     char buffer[4096];
     unsigned int numFound = 0;
 
@@ -67,9 +69,10 @@
     buffer[len] = 0;
 
     static const char* const tags[] = {
-            "MemTotal:",     "MemFree:",    "Buffers:",     "Cached:",       "Shmem:", "Slab:",
-            "SReclaimable:", "SUnreclaim:", "SwapTotal:",   "SwapFree:",     "ZRam:",  "Mapped:",
-            "VmallocUsed:",  "PageTables:", "KernelStack:", NULL};
+            "MemTotal:",     "MemFree:",    "Buffers:",     "Cached:",   "Shmem:", "Slab:",
+            "SReclaimable:", "SUnreclaim:", "SwapTotal:",   "SwapFree:", "ZRam:",  "Mapped:",
+            "VmallocUsed:",  "PageTables:", "KernelStack:", NULL
+    };
 
     static const int tagsLen[] = {9, 8, 8, 7, 6, 5, 13, 11, 10, 9, 5, 7, 12, 11, 12, 0};
 
@@ -78,7 +81,8 @@
     while (*p && (numFound < (sizeof(tagsLen) / sizeof(tagsLen[0])))) {
         int i = 0;
         while (tags[i]) {
-            //std::cout << "tag =" << tags[i] << " p = " << std::string(p, tagsLen[i]) << std::endl;
+            // std::cout << "tag =" << tags[i] << " p = " << std::string(p, tagsLen[i]) <<
+            // std::endl;
             if (strncmp(p, tags[i], tagsLen[i]) == 0) {
                 p += tagsLen[i];
                 while (*p == ' ') p++;
@@ -214,4 +218,51 @@
 }
 BENCHMARK(BM_ReadMemInfo);
 
+static uint64_t get_zram_mem_used(const std::string& zram_dir) {
+    FILE* f = fopen((zram_dir + "mm_stat").c_str(), "r");
+    if (f) {
+        uint64_t mem_used_total = 0;
+
+        int matched = fscanf(f, "%*d %*d %" SCNu64 " %*d %*d %*d %*d", &mem_used_total);
+        if (matched != 1)
+            fprintf(stderr, "warning: failed to parse %s\n", (zram_dir + "mm_stat").c_str());
+
+        fclose(f);
+        return mem_used_total;
+    }
+
+    f = fopen((zram_dir + "mem_used_total").c_str(), "r");
+    if (f) {
+        uint64_t mem_used_total = 0;
+
+        int matched = fscanf(f, "%" SCNu64, &mem_used_total);
+        if (matched != 1)
+            fprintf(stderr, "warning: failed to parse %s\n", (zram_dir + "mem_used_total").c_str());
+
+        fclose(f);
+        return mem_used_total;
+    }
+
+    return 0;
+}
+
+static void BM_OldReadZramTotal(benchmark::State& state) {
+    std::string exec_dir = ::android::base::GetExecutableDirectory();
+    std::string zram_mmstat_dir = exec_dir + "/testdata1/";
+    for (auto _ : state) {
+        uint64_t zram_total __attribute__((unused)) = get_zram_mem_used(zram_mmstat_dir) / 1024;
+    }
+}
+BENCHMARK(BM_OldReadZramTotal);
+
+static void BM_NewReadZramTotal(benchmark::State& state) {
+    std::string exec_dir = ::android::base::GetExecutableDirectory();
+    std::string zram_mmstat_dir = exec_dir + "/testdata1/";
+    ::android::meminfo::SysMemInfo mi;
+    for (auto _ : state) {
+        uint64_t zram_total __attribute__((unused)) = mi.mem_zram_kb(zram_mmstat_dir);
+    }
+}
+BENCHMARK(BM_NewReadZramTotal);
+
 BENCHMARK_MAIN();
diff --git a/libmeminfo/libmeminfo_test.cpp b/libmeminfo/libmeminfo_test.cpp
index 7a2be41..b7a4b6b 100644
--- a/libmeminfo/libmeminfo_test.cpp
+++ b/libmeminfo/libmeminfo_test.cpp
@@ -73,7 +73,7 @@
     }
 }
 
-TEST_F(ValidateProcMemInfo, TestMapsUsage) {
+TEST_F(ValidateProcMemInfo, TestMaps) {
     const std::vector<Vma>& maps = proc_mem->Maps();
     ASSERT_FALSE(maps.empty());
     ASSERT_EQ(proc->num_maps, maps.size());
@@ -96,6 +96,30 @@
     EXPECT_EQ(proc_usage.uss, proc_mem->Usage().uss);
 }
 
+TEST_F(ValidateProcMemInfo, TestSwapUsage) {
+    const std::vector<Vma>& maps = proc_mem->Maps();
+    ASSERT_FALSE(maps.empty());
+    ASSERT_EQ(proc->num_maps, maps.size());
+
+    pm_memusage_t map_usage, proc_usage;
+    pm_memusage_zero(&map_usage);
+    pm_memusage_zero(&proc_usage);
+    for (size_t i = 0; i < maps.size(); i++) {
+        ASSERT_EQ(0, pm_map_usage(proc->maps[i], &map_usage));
+        EXPECT_EQ(map_usage.swap, maps[i].usage.swap) << "SWAP mismatch for map: " << maps[i].name;
+        pm_memusage_add(&proc_usage, &map_usage);
+    }
+
+    EXPECT_EQ(proc_usage.swap, proc_mem->Usage().swap);
+}
+
+TEST_F(ValidateProcMemInfo, TestSwapOffsets) {
+    const MemUsage& proc_usage = proc_mem->Usage();
+    const std::vector<uint16_t>& swap_offsets = proc_mem->SwapOffsets();
+
+    EXPECT_EQ(proc_usage.swap / getpagesize(), swap_offsets.size());
+}
+
 class ValidateProcMemInfoWss : public ::testing::Test {
   protected:
     void SetUp() override {
@@ -118,7 +142,7 @@
 
 TEST_F(ValidateProcMemInfoWss, TestWorkingTestReset) {
     // Expect reset to succeed
-    EXPECT_TRUE(proc_mem->WssReset());
+    EXPECT_TRUE(ProcMemInfo::ResetWorkingSet(pid));
 }
 
 TEST_F(ValidateProcMemInfoWss, TestWssEquality) {
@@ -221,6 +245,93 @@
     }
 }
 
+TEST(TestProcMemInfo, TestMapsEmpty) {
+    ProcMemInfo proc_mem(pid);
+    const std::vector<Vma>& maps = proc_mem.Maps();
+    EXPECT_GT(maps.size(), 0);
+}
+
+TEST(TestProcMemInfo, TestUsageEmpty) {
+    // If we created the object for getting working set,
+    // the usage must be empty
+    ProcMemInfo proc_mem(pid, true);
+    const MemUsage& usage = proc_mem.Usage();
+    EXPECT_EQ(usage.rss, 0);
+    EXPECT_EQ(usage.vss, 0);
+    EXPECT_EQ(usage.pss, 0);
+    EXPECT_EQ(usage.uss, 0);
+    EXPECT_EQ(usage.swap, 0);
+}
+
+TEST(TestProcMemInfoWssReset, TestWssEmpty) {
+    // If we created the object for getting usage,
+    // the working set must be empty
+    ProcMemInfo proc_mem(pid, false);
+    const MemUsage& wss = proc_mem.Wss();
+    EXPECT_EQ(wss.rss, 0);
+    EXPECT_EQ(wss.vss, 0);
+    EXPECT_EQ(wss.pss, 0);
+    EXPECT_EQ(wss.uss, 0);
+    EXPECT_EQ(wss.swap, 0);
+}
+
+TEST(TestProcMemInfoWssReset, TestSwapOffsetsEmpty) {
+    // If we created the object for getting working set,
+    // the swap offsets must be empty
+    ProcMemInfo proc_mem(pid, true);
+    const std::vector<uint16_t>& swap_offsets = proc_mem.SwapOffsets();
+    EXPECT_EQ(swap_offsets.size(), 0);
+}
+
+TEST(ValidateProcMemInfoFlags, TestPageFlags1) {
+    // Create proc object using libpagemap
+    pm_kernel_t* ker;
+    ASSERT_EQ(0, pm_kernel_create(&ker));
+    pm_process_t* proc;
+    ASSERT_EQ(0, pm_process_create(ker, pid, &proc));
+
+    // count swapbacked pages using libpagemap
+    pm_memusage_t proc_usage;
+    pm_memusage_zero(&proc_usage);
+    ASSERT_EQ(0, pm_process_usage_flags(proc, &proc_usage, (1 << KPF_SWAPBACKED),
+                                        (1 << KPF_SWAPBACKED)));
+
+    // Create ProcMemInfo that counts swapbacked pages
+    ProcMemInfo proc_mem(pid, false, (1 << KPF_SWAPBACKED), (1 << KPF_SWAPBACKED));
+
+    EXPECT_EQ(proc_usage.vss, proc_mem.Usage().vss);
+    EXPECT_EQ(proc_usage.rss, proc_mem.Usage().rss);
+    EXPECT_EQ(proc_usage.pss, proc_mem.Usage().pss);
+    EXPECT_EQ(proc_usage.uss, proc_mem.Usage().uss);
+
+    pm_process_destroy(proc);
+    pm_kernel_destroy(ker);
+}
+
+TEST(ValidateProcMemInfoFlags, TestPageFlags2) {
+    // Create proc object using libpagemap
+    pm_kernel_t* ker;
+    ASSERT_EQ(0, pm_kernel_create(&ker));
+    pm_process_t* proc;
+    ASSERT_EQ(0, pm_process_create(ker, pid, &proc));
+
+    // count non-swapbacked pages using libpagemap
+    pm_memusage_t proc_usage;
+    pm_memusage_zero(&proc_usage);
+    ASSERT_EQ(0, pm_process_usage_flags(proc, &proc_usage, (1 << KPF_SWAPBACKED), 0));
+
+    // Create ProcMemInfo that counts non-swapbacked pages
+    ProcMemInfo proc_mem(pid, false, 0, (1 << KPF_SWAPBACKED));
+
+    EXPECT_EQ(proc_usage.vss, proc_mem.Usage().vss);
+    EXPECT_EQ(proc_usage.rss, proc_mem.Usage().rss);
+    EXPECT_EQ(proc_usage.pss, proc_mem.Usage().pss);
+    EXPECT_EQ(proc_usage.uss, proc_mem.Usage().uss);
+
+    pm_process_destroy(proc);
+    pm_kernel_destroy(ker);
+}
+
 TEST(SysMemInfoParser, TestSysMemInfoFile) {
     std::string meminfo = R"meminfo(MemTotal:        3019740 kB
 MemFree:         1809728 kB
@@ -288,6 +399,17 @@
     EXPECT_EQ(mi.mem_total_kb(), 0);
 }
 
+TEST(SysMemInfoParse, TestZramTotal) {
+    std::string exec_dir = ::android::base::GetExecutableDirectory();
+
+    SysMemInfo mi;
+    std::string zram_mmstat_dir = exec_dir + "/testdata1/";
+    EXPECT_EQ(mi.mem_zram_kb(zram_mmstat_dir), 30504);
+
+    std::string zram_memused_dir = exec_dir + "/testdata2/";
+    EXPECT_EQ(mi.mem_zram_kb(zram_memused_dir), 30504);
+}
+
 int main(int argc, char** argv) {
     ::testing::InitGoogleTest(&argc, argv);
     if (argc <= 1) {
diff --git a/libmeminfo/procmeminfo.cpp b/libmeminfo/procmeminfo.cpp
index fe91d25..8867e14 100644
--- a/libmeminfo/procmeminfo.cpp
+++ b/libmeminfo/procmeminfo.cpp
@@ -44,6 +44,8 @@
     to->pss += from.pss;
     to->uss += from.uss;
 
+    to->swap += from.swap;
+
     to->private_clean += from.private_clean;
     to->private_dirty += from.private_dirty;
 
@@ -51,48 +53,78 @@
     to->shared_dirty += from.shared_dirty;
 }
 
-ProcMemInfo::ProcMemInfo(pid_t pid, bool get_wss) : pid_(pid), get_wss_(get_wss) {
-    if (!ReadMaps(get_wss_)) {
-        LOG(ERROR) << "Failed to read maps for Process " << pid_;
-    }
-}
-
-const std::vector<Vma>& ProcMemInfo::Maps() {
-    return maps_;
-}
-
-const MemUsage& ProcMemInfo::Usage() {
-    if (get_wss_) {
-        LOG(WARNING) << "Trying to read memory usage from working set object";
-    }
-    return usage_;
-}
-
-const MemUsage& ProcMemInfo::Wss() {
-    if (!get_wss_) {
-        LOG(WARNING) << "Trying to read working set when there is none";
-    }
-
-    return wss_;
-}
-
-bool ProcMemInfo::WssReset() {
-    if (!get_wss_) {
-        LOG(ERROR) << "Trying to reset working set from a memory usage counting object";
-        return false;
-    }
-
-    std::string clear_refs_path = ::android::base::StringPrintf("/proc/%d/clear_refs", pid_);
+bool ProcMemInfo::ResetWorkingSet(pid_t pid) {
+    std::string clear_refs_path = ::android::base::StringPrintf("/proc/%d/clear_refs", pid);
     if (!::android::base::WriteStringToFile("1\n", clear_refs_path)) {
         PLOG(ERROR) << "Failed to write to " << clear_refs_path;
         return false;
     }
 
-    wss_.clear();
     return true;
 }
 
+ProcMemInfo::ProcMemInfo(pid_t pid, bool get_wss, uint64_t pgflags, uint64_t pgflags_mask)
+    : pid_(pid), get_wss_(get_wss), pgflags_(pgflags), pgflags_mask_(pgflags_mask) {}
+
+const std::vector<Vma>& ProcMemInfo::Maps() {
+    if (maps_.empty() && !ReadMaps(get_wss_)) {
+        LOG(ERROR) << "Failed to read maps for Process " << pid_;
+    }
+
+    return maps_;
+}
+
+const MemUsage& ProcMemInfo::Usage() {
+    if (get_wss_) {
+        LOG(WARNING) << "Trying to read process memory usage for " << pid_
+                     << " using invalid object";
+        return usage_;
+    }
+
+    if (maps_.empty() && !ReadMaps(get_wss_)) {
+        LOG(ERROR) << "Failed to get memory usage for Process " << pid_;
+    }
+
+    return usage_;
+}
+
+const MemUsage& ProcMemInfo::Wss() {
+    if (!get_wss_) {
+        LOG(WARNING) << "Trying to read process working set for " << pid_
+                     << " using invalid object";
+        return wss_;
+    }
+
+    if (maps_.empty() && !ReadMaps(get_wss_)) {
+        LOG(ERROR) << "Failed to get working set for Process " << pid_;
+    }
+
+    return wss_;
+}
+
+const std::vector<uint16_t>& ProcMemInfo::SwapOffsets() {
+    if (get_wss_) {
+        LOG(WARNING) << "Trying to read process swap offsets for " << pid_
+                     << " using invalid object";
+        return swap_offsets_;
+    }
+
+    if (maps_.empty() && !ReadMaps(get_wss_)) {
+        LOG(ERROR) << "Failed to get swap offsets for Process " << pid_;
+    }
+
+    return swap_offsets_;
+}
+
 bool ProcMemInfo::ReadMaps(bool get_wss) {
+    // Each object reads /proc/<pid>/maps only once. This is done to make sure programs that are
+    // running for the lifetime of the system can recycle the objects and don't have to
+    // unnecessarily retain and update this object in memory (which can get significantly large).
+    // E.g. A program that only needs to reset the working set will never all ->Maps(), ->Usage().
+    // E.g. A program that is monitoring smaps_rollup, may never call ->maps(), Usage(), so it
+    // doesn't make sense for us to parse and retain unnecessary memory accounting stats by default.
+    if (!maps_.empty()) return true;
+
     // parse and read /proc/<pid>/maps
     std::string maps_file = ::android::base::StringPrintf("/proc/%d/maps", pid_);
     if (!::android::procinfo::ReadMapFile(
@@ -115,8 +147,8 @@
 
     for (auto& vma : maps_) {
         if (!ReadVmaStats(pagemap_fd.get(), vma, get_wss)) {
-            LOG(ERROR) << "Failed to read page map for vma " << vma.name << "[" << vma.start
-                       << "-" << vma.end << "]";
+            LOG(ERROR) << "Failed to read page map for vma " << vma.name << "[" << vma.start << "-"
+                       << vma.end << "]";
             maps_.clear();
             return false;
         }
@@ -153,18 +185,24 @@
         if (!PAGE_PRESENT(p) && !PAGE_SWAPPED(p)) continue;
 
         if (PAGE_SWAPPED(p)) {
-            // TODO: do what's needed for swapped pages
+            vma.usage.swap += pagesz;
+            swap_offsets_.emplace_back(PAGE_SWAP_OFFSET(p));
             continue;
         }
 
         uint64_t page_frame = PAGE_PFN(p);
         if (!pinfo.PageFlags(page_frame, &pg_flags[i])) {
             LOG(ERROR) << "Failed to get page flags for " << page_frame << " in process " << pid_;
+            swap_offsets_.clear();
             return false;
         }
 
+        // skip unwanted pages from the count
+        if ((pg_flags[i] & pgflags_mask_) != pgflags_) continue;
+
         if (!pinfo.PageMapCount(page_frame, &pg_counts[i])) {
             LOG(ERROR) << "Failed to get page count for " << page_frame << " in process " << pid_;
+            swap_offsets_.clear();
             return false;
         }
 
diff --git a/libmeminfo/sysmeminfo.cpp b/libmeminfo/sysmeminfo.cpp
index 50fa213..7e56238 100644
--- a/libmeminfo/sysmeminfo.cpp
+++ b/libmeminfo/sysmeminfo.cpp
@@ -17,10 +17,12 @@
 #include <ctype.h>
 #include <errno.h>
 #include <fcntl.h>
+#include <inttypes.h>
 #include <stdlib.h>
 #include <unistd.h>
 
 #include <cctype>
+#include <cstdio>
 #include <fstream>
 #include <string>
 #include <utility>
@@ -29,7 +31,9 @@
 #include <android-base/file.h>
 #include <android-base/logging.h>
 #include <android-base/parseint.h>
+#include <android-base/stringprintf.h>
 #include <android-base/strings.h>
+#include <android-base/unique_fd.h>
 
 #include "meminfo_private.h"
 
@@ -37,9 +41,11 @@
 namespace meminfo {
 
 const std::vector<std::string> SysMemInfo::kDefaultSysMemInfoTags = {
-    "MemTotal:", "MemFree:",      "Buffers:",     "Cached:",     "Shmem:",
-    "Slab:",     "SReclaimable:", "SUnreclaim:",  "SwapTotal:",  "SwapFree:",
-    "ZRam:",     "Mapped:",       "VmallocUsed:", "PageTables:", "KernelStack:",
+        SysMemInfo::kMemTotal,      SysMemInfo::kMemFree,        SysMemInfo::kMemBuffers,
+        SysMemInfo::kMemCached,     SysMemInfo::kMemShmem,       SysMemInfo::kMemSlab,
+        SysMemInfo::kMemSReclaim,   SysMemInfo::kMemSUnreclaim,  SysMemInfo::kMemSwapTotal,
+        SysMemInfo::kMemSwapFree,   SysMemInfo::kMemMapped,      SysMemInfo::kMemVmallocUsed,
+        SysMemInfo::kMemPageTables, SysMemInfo::kMemKernelStack,
 };
 
 bool SysMemInfo::ReadMemInfo(const std::string& path) {
@@ -99,6 +105,7 @@
     buffer[len] = '\0';
     char* p = buffer;
     uint32_t found = 0;
+    uint32_t lineno = 0;
     while (*p && found < tags.size()) {
         for (auto& tag : tags) {
             if (strncmp(p, tag.c_str(), tag.size()) == 0) {
@@ -107,7 +114,7 @@
                 char* endptr = nullptr;
                 mem_in_kb_[tag] = strtoull(p, &endptr, 10);
                 if (p == endptr) {
-                    PLOG(ERROR) << "Failed to parse line in file: " << path;
+                    PLOG(ERROR) << "Failed to parse line:" << lineno + 1 << " in file: " << path;
                     return false;
                 }
                 p = endptr;
@@ -119,11 +126,75 @@
             p++;
         }
         if (*p) p++;
+        lineno++;
     }
 
     return true;
 }
 #endif
 
+uint64_t SysMemInfo::mem_zram_kb(const std::string& zram_dev) {
+    uint64_t mem_zram_total = 0;
+    if (!zram_dev.empty()) {
+        if (!MemZramDevice(zram_dev, &mem_zram_total)) {
+            return 0;
+        }
+        return mem_zram_total / 1024;
+    }
+
+    constexpr uint32_t kMaxZramDevices = 256;
+    for (uint32_t i = 0; i < kMaxZramDevices; i++) {
+        std::string zram_dev = ::android::base::StringPrintf("/sys/block/zram%u/", i);
+        if (access(zram_dev.c_str(), F_OK)) {
+            // We assume zram devices appear in range 0-255 and appear always in sequence
+            // under /sys/block. So, stop looking for them once we find one is missing.
+            break;
+        }
+
+        uint64_t mem_zram_dev;
+        if (!MemZramDevice(zram_dev, &mem_zram_dev)) {
+            return 0;
+        }
+
+        mem_zram_total += mem_zram_dev;
+    }
+
+    return mem_zram_total / 1024;
+}
+
+bool SysMemInfo::MemZramDevice(const std::string& zram_dev, uint64_t* mem_zram_dev) {
+    std::string content;
+    if (android::base::ReadFileToString(zram_dev + "mm_stat", &content)) {
+        std::vector<std::string> values = ::android::base::Split(content, " ");
+        if (values.size() < 3) {
+            LOG(ERROR) << "Malformed mm_stat file for zram dev: " << zram_dev
+                       << " content: " << content;
+            return false;
+        }
+
+        if (!::android::base::ParseUint(values[2], mem_zram_dev)) {
+            LOG(ERROR) << "Malformed mm_stat file for zram dev: " << zram_dev
+                       << " value: " << values[2];
+            return false;
+        }
+
+        return true;
+    }
+
+    if (::android::base::ReadFileToString(zram_dev + "mem_used_total", &content)) {
+        *mem_zram_dev = strtoull(content.c_str(), NULL, 10);
+        if (*mem_zram_dev == ULLONG_MAX) {
+            PLOG(ERROR) << "Malformed mem_used_total file for zram dev: " << zram_dev
+                        << " content: " << content;
+            return false;
+        }
+
+        return true;
+    }
+
+    LOG(ERROR) << "Can't find memory status under: " << zram_dev;
+    return false;
+}
+
 }  // namespace meminfo
 }  // namespace android
diff --git a/libmeminfo/testdata1/mm_stat b/libmeminfo/testdata1/mm_stat
new file mode 100644
index 0000000..684f567
--- /dev/null
+++ b/libmeminfo/testdata1/mm_stat
@@ -0,0 +1 @@
+145674240 26801454 31236096        0 45772800     3042     1887      517
diff --git a/libmeminfo/testdata2/mem_used_total b/libmeminfo/testdata2/mem_used_total
new file mode 100644
index 0000000..97fcf41
--- /dev/null
+++ b/libmeminfo/testdata2/mem_used_total
@@ -0,0 +1 @@
+31236096
diff --git a/libmeminfo/tools/Android.bp b/libmeminfo/tools/Android.bp
index 0870130..7c41660 100644
--- a/libmeminfo/tools/Android.bp
+++ b/libmeminfo/tools/Android.bp
@@ -25,3 +25,18 @@
         "libmeminfo",
     ],
 }
+
+cc_binary {
+    name: "procrank2",
+    cflags: [
+        "-Wall",
+        "-Werror",
+        "-Wno-unused-parameter",
+    ],
+
+    srcs: ["procrank.cpp"],
+    shared_libs: [
+        "libbase",
+        "libmeminfo",
+    ],
+}
diff --git a/libmeminfo/tools/procmem.cpp b/libmeminfo/tools/procmem.cpp
index 3571e41..d30c2f2 100644
--- a/libmeminfo/tools/procmem.cpp
+++ b/libmeminfo/tools/procmem.cpp
@@ -66,14 +66,12 @@
     // clear string stream first.
     ss.str("");
     // TODO: use ::android::base::StringPrintf instead of <iomanip> here.
-    if (!show_wss)
-        ss << std::setw(6) << usage.vss/1024 << padding;
-    ss << std::setw(6) << usage.rss/1024 << padding << std::setw(6)
-       << usage.pss/1024 << padding << std::setw(6) << usage.uss/1024 << padding
-       << std::setw(6) << usage.shared_clean/1024 << padding << std::setw(6)
-       << usage.shared_dirty/1024 << padding << std::setw(6)
-       << usage.private_clean/1024 << padding << std::setw(6)
-       << usage.private_dirty/1024 << padding;
+    if (!show_wss) ss << std::setw(6) << usage.vss / 1024 << padding;
+    ss << std::setw(6) << usage.rss / 1024 << padding << std::setw(6) << usage.pss / 1024 << padding
+       << std::setw(6) << usage.uss / 1024 << padding << std::setw(6) << usage.shared_clean / 1024
+       << padding << std::setw(6) << usage.shared_dirty / 1024 << padding << std::setw(6)
+       << usage.private_clean / 1024 << padding << std::setw(6) << usage.private_dirty / 1024
+       << padding;
 }
 
 static int show(ProcMemInfo& proc, bool hide_zeroes, bool show_wss) {
@@ -158,14 +156,14 @@
     }
 
     bool need_wss = wss_reset || show_wss;
-    ProcMemInfo proc(pid, need_wss);
     if (wss_reset) {
-        if (!proc.WssReset()) {
+        if (!ProcMemInfo::ResetWorkingSet(pid)) {
             std::cerr << "Failed to reset working set of pid : " << pid << std::endl;
             exit(EXIT_FAILURE);
         }
         return 0;
     }
 
+    ProcMemInfo proc(pid, need_wss);
     return show(proc, hide_zeroes, show_wss);
 }
diff --git a/libmeminfo/tools/procrank.cpp b/libmeminfo/tools/procrank.cpp
new file mode 100644
index 0000000..e39e7fa
--- /dev/null
+++ b/libmeminfo/tools/procrank.cpp
@@ -0,0 +1,530 @@
+/*
+ * Copyright (C) 2018 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 <dirent.h>
+#include <errno.h>
+#include <inttypes.h>
+#include <linux/kernel-page-flags.h>
+#include <linux/oom.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#include <iostream>
+#include <memory>
+#include <sstream>
+#include <vector>
+
+#include <android-base/file.h>
+#include <android-base/parseint.h>
+#include <android-base/stringprintf.h>
+#include <android-base/strings.h>
+
+#include <meminfo/procmeminfo.h>
+#include <meminfo/sysmeminfo.h>
+
+using ::android::meminfo::MemUsage;
+using ::android::meminfo::ProcMemInfo;
+
+struct ProcessRecord {
+  public:
+    ProcessRecord(pid_t pid, bool get_wss = false, uint64_t pgflags = 0, uint64_t pgflags_mask = 0)
+        : pid_(-1),
+          procmem_(nullptr),
+          oomadj_(OOM_SCORE_ADJ_MAX + 1),
+          cmdline_(""),
+          proportional_swap_(0),
+          unique_swap_(0),
+          zswap_(0) {
+        std::unique_ptr<ProcMemInfo> procmem =
+                std::make_unique<ProcMemInfo>(pid, get_wss, pgflags, pgflags_mask);
+        if (procmem == nullptr) {
+            std::cerr << "Failed to create ProcMemInfo for: " << pid << std::endl;
+            return;
+        }
+
+        std::string fname = ::android::base::StringPrintf("/proc/%d/oom_score_adj", pid);
+        auto oomscore_fp =
+                std::unique_ptr<FILE, decltype(&fclose)>{fopen(fname.c_str(), "re"), fclose};
+        if (oomscore_fp == nullptr) {
+            std::cerr << "Failed to open oom_score_adj file: " << fname << std::endl;
+            return;
+        }
+
+        if (fscanf(oomscore_fp.get(), "%d\n", &oomadj_) != 1) {
+            std::cerr << "Failed to read oomadj from: " << fname << std::endl;
+            return;
+        }
+
+        fname = ::android::base::StringPrintf("/proc/%d/cmdline", pid);
+        if (!::android::base::ReadFileToString(fname, &cmdline_)) {
+            std::cerr << "Failed to read cmdline from: " << fname << std::endl;
+            cmdline_ = "<unknown>";
+        }
+        // We deliberately don't read the proc/<pid>cmdline file directly into 'cmdline_'
+        // because of some processes showing up cmdlines that end with "0x00 0x0A 0x00"
+        // e.g. xtra-daemon, lowi-server
+        // The .c_str() assignment below then takes care of trimming the cmdline at the first
+        // 0x00. This is how original procrank worked (luckily)
+        cmdline_.resize(strlen(cmdline_.c_str()));
+        procmem_ = std::move(procmem);
+        pid_ = pid;
+    }
+
+    bool valid() const { return pid_ != -1; }
+
+    void CalculateSwap(const uint16_t* swap_offset_array, float zram_compression_ratio) {
+        const std::vector<uint16_t>& swp_offs = procmem_->SwapOffsets();
+        for (auto& off : swp_offs) {
+            proportional_swap_ += getpagesize() / swap_offset_array[off];
+            unique_swap_ += swap_offset_array[off] == 1 ? getpagesize() : 0;
+            zswap_ = proportional_swap_ * zram_compression_ratio;
+        }
+    }
+
+    // Getters
+    pid_t pid() const { return pid_; }
+    const std::string& cmdline() const { return cmdline_; }
+    int32_t oomadj() const { return oomadj_; }
+    uint64_t proportional_swap() const { return proportional_swap_; }
+    uint64_t unique_swap() const { return unique_swap_; }
+    uint64_t zswap() const { return zswap_; }
+
+    // Wrappers to ProcMemInfo
+    const std::vector<uint16_t>& SwapOffsets() const { return procmem_->SwapOffsets(); }
+    const MemUsage& Usage() const { return procmem_->Usage(); }
+    const MemUsage& Wss() const { return procmem_->Wss(); }
+
+  private:
+    pid_t pid_;
+    std::unique_ptr<ProcMemInfo> procmem_;
+    int32_t oomadj_;
+    std::string cmdline_;
+    uint64_t proportional_swap_;
+    uint64_t unique_swap_;
+    uint64_t zswap_;
+};
+
+// Show working set instead of memory consumption
+bool show_wss = false;
+// Reset working set of each process
+bool reset_wss = false;
+// Show per-process oom_score_adj column
+bool show_oomadj = false;
+// True if the device has swap enabled
+bool has_swap = false;
+// True, if device has zram enabled
+bool has_zram = false;
+// If zram is enabled, the compression ratio is zram used / swap used.
+float zram_compression_ratio = 0.0;
+// Sort process in reverse, default is descending
+bool reverse_sort = false;
+
+// Calculated total memory usage across all processes in the system
+uint64_t total_pss = 0;
+uint64_t total_uss = 0;
+uint64_t total_swap = 0;
+uint64_t total_pswap = 0;
+uint64_t total_uswap = 0;
+uint64_t total_zswap = 0;
+
+static void usage(const char* myname) {
+    std::cerr << "Usage: " << myname << " [ -W ] [ -v | -r | -p | -u | -s | -h ]" << std::endl
+              << "    -v  Sort by VSS." << std::endl
+              << "    -r  Sort by RSS." << std::endl
+              << "    -p  Sort by PSS." << std::endl
+              << "    -u  Sort by USS." << std::endl
+              << "    -s  Sort by swap." << std::endl
+              << "        (Default sort order is PSS.)" << std::endl
+              << "    -R  Reverse sort order (default is descending)." << std::endl
+              << "    -c  Only show cached (storage backed) pages" << std::endl
+              << "    -C  Only show non-cached (ram/swap backed) pages" << std::endl
+              << "    -k  Only show pages collapsed by KSM" << std::endl
+              << "    -w  Display statistics for working set only." << std::endl
+              << "    -W  Reset working set of all processes." << std::endl
+              << "    -o  Show and sort by oom score against lowmemorykiller thresholds."
+              << std::endl
+              << "    -h  Display this help screen." << std::endl;
+}
+
+static bool read_all_pids(std::vector<pid_t>* pids, std::function<bool(pid_t pid)> for_each_pid) {
+    pids->clear();
+    std::unique_ptr<DIR, int (*)(DIR*)> procdir(opendir("/proc"), closedir);
+    if (!procdir) return false;
+
+    struct dirent* dir;
+    pid_t pid;
+    while ((dir = readdir(procdir.get()))) {
+        if (!::android::base::ParseInt(dir->d_name, &pid)) continue;
+        if (!for_each_pid(pid)) return false;
+        pids->push_back(pid);
+    }
+
+    return true;
+}
+
+static bool count_swap_offsets(const ProcessRecord& proc, uint16_t* swap_offset_array,
+                               uint32_t size) {
+    const std::vector<uint16_t>& swp_offs = proc.SwapOffsets();
+    for (auto& off : swp_offs) {
+        if (off >= size) {
+            std::cerr << "swap offset " << off << " is out of bounds for process: " << proc.pid()
+                      << std::endl;
+            return false;
+        }
+
+        if (swap_offset_array[off] == USHRT_MAX) {
+            std::cerr << "swap offset " << off << " ref count overflow in process: " << proc.pid()
+                      << std::endl;
+            return false;
+        }
+
+        swap_offset_array[off]++;
+    }
+
+    return true;
+}
+
+static void print_header(std::stringstream& ss) {
+    ss.str("");
+    ss << ::android::base::StringPrintf("%5s  ", "PID");
+    if (show_oomadj) {
+        ss << ::android::base::StringPrintf("%5s  ", "oom");
+    }
+
+    if (show_wss) {
+        ss << ::android::base::StringPrintf("%7s  %7s  %7s  ", "WRss", "WPss", "WUss");
+        // now swap statistics here, working set pages by definition shouldn't end up in swap.
+    } else {
+        ss << ::android::base::StringPrintf("%8s  %7s  %7s  %7s  ", "Vss", "Rss", "Pss", "Uss");
+        if (has_swap) {
+            ss << ::android::base::StringPrintf("%7s  %7s  %7s  ", "Swap", "PSwap", "USwap");
+            if (has_zram) {
+                ss << ::android::base::StringPrintf("%7s  ", "ZSwap");
+            }
+        }
+    }
+
+    ss << "cmdline";
+}
+
+static void print_process_record(std::stringstream& ss, ProcessRecord& proc) {
+    ss << ::android::base::StringPrintf("%5d  ", proc.pid());
+    if (show_oomadj) {
+        ss << ::android::base::StringPrintf("%5d  ", proc.oomadj());
+    }
+
+    if (show_wss) {
+        ss << ::android::base::StringPrintf("%6" PRIu64 "K  %6" PRIu64 "K  %6" PRIu64 "K  ",
+                                            proc.Wss().rss / 1024, proc.Wss().pss / 1024,
+                                            proc.Wss().uss / 1024);
+    } else {
+        ss << ::android::base::StringPrintf("%7" PRIu64 "K  %6" PRIu64 "K  %6" PRIu64 "K  %6" PRIu64
+                                            "K  ",
+                                            proc.Usage().vss / 1024, proc.Usage().rss / 1024,
+                                            proc.Usage().pss / 1024, proc.Usage().uss / 1024);
+        if (has_swap) {
+            ss << ::android::base::StringPrintf("%6" PRIu64 "K  ", proc.Usage().swap / 1024);
+            ss << ::android::base::StringPrintf("%6" PRIu64 "K  ", proc.proportional_swap() / 1024);
+            ss << ::android::base::StringPrintf("%6" PRIu64 "K  ", proc.unique_swap() / 1024);
+            if (has_zram) {
+                ss << ::android::base::StringPrintf("%6" PRIu64 "K  ", (proc.zswap() / 1024));
+            }
+        }
+    }
+}
+
+static void print_processes(std::stringstream& ss, std::vector<ProcessRecord>& procs,
+                            uint16_t* swap_offset_array) {
+    for (auto& proc : procs) {
+        total_pss += show_wss ? proc.Wss().pss : proc.Usage().pss;
+        total_uss += show_wss ? proc.Wss().uss : proc.Usage().uss;
+        if (!show_wss && has_swap) {
+            proc.CalculateSwap(swap_offset_array, zram_compression_ratio);
+            total_swap += proc.Usage().swap;
+            total_pswap += proc.proportional_swap();
+            total_uswap += proc.unique_swap();
+            if (has_zram) {
+                total_zswap += proc.zswap();
+            }
+        }
+
+        print_process_record(ss, proc);
+        ss << proc.cmdline() << std::endl;
+    }
+}
+
+static void print_separator(std::stringstream& ss) {
+    ss << ::android::base::StringPrintf("%5s  ", "");
+    if (show_oomadj) {
+        ss << ::android::base::StringPrintf("%5s  ", "");
+    }
+
+    if (show_wss) {
+        ss << ::android::base::StringPrintf("%7s  %7s  %7s  ", "", "------", "------");
+    } else {
+        ss << ::android::base::StringPrintf("%8s  %7s  %7s  %7s  ", "", "", "------", "------");
+        if (has_swap) {
+            ss << ::android::base::StringPrintf("%7s  %7s  %7s  ", "------", "------", "------");
+            if (has_zram) {
+                ss << ::android::base::StringPrintf("%7s  ", "------");
+            }
+        }
+    }
+
+    ss << ::android::base::StringPrintf("%s", "------");
+}
+
+static void print_totals(std::stringstream& ss) {
+    ss << ::android::base::StringPrintf("%5s  ", "");
+    if (show_oomadj) {
+        ss << ::android::base::StringPrintf("%5s  ", "");
+    }
+
+    if (show_wss) {
+        ss << ::android::base::StringPrintf("%7s  %6" PRIu64 "K  %6" PRIu64 "K  ", "",
+                                            total_pss / 1024, total_uss / 1024);
+    } else {
+        ss << ::android::base::StringPrintf("%8s  %7s  %6" PRIu64 "K  %6" PRIu64 "K  ", "", "",
+                                            total_pss / 1024, total_uss / 1024);
+        if (has_swap) {
+            ss << ::android::base::StringPrintf("%6" PRIu64 "K  ", total_swap / 1024);
+            ss << ::android::base::StringPrintf("%6" PRIu64 "K  ", total_pswap / 1024);
+            ss << ::android::base::StringPrintf("%6" PRIu64 "K  ", total_uswap / 1024);
+            if (has_zram) {
+                ss << ::android::base::StringPrintf("%6" PRIu64 "K  ", total_zswap / 1024);
+            }
+        }
+    }
+    ss << "TOTAL";
+}
+
+static void print_sysmeminfo(std::stringstream& ss, ::android::meminfo::SysMemInfo& smi) {
+    if (has_swap) {
+        ss << ::android::base::StringPrintf("ZRAM: %" PRIu64 "K physical used for %" PRIu64
+                                            "K in swap "
+                                            "(%" PRIu64 "K total swap)",
+                                            smi.mem_zram_kb(),
+                                            (smi.mem_swap_kb() - smi.mem_swap_free_kb()),
+                                            smi.mem_swap_kb())
+           << std::endl;
+    }
+
+    ss << ::android::base::StringPrintf(" RAM: %" PRIu64 "K total, %" PRIu64 "K free, %" PRIu64
+                                        "K buffers, "
+                                        "%" PRIu64 "K cached, %" PRIu64 "K shmem, %" PRIu64
+                                        "K slab",
+                                        smi.mem_total_kb(), smi.mem_free_kb(), smi.mem_buffers_kb(),
+                                        smi.mem_cached_kb(), smi.mem_shmem_kb(), smi.mem_slab_kb());
+}
+
+int main(int argc, char* argv[]) {
+    auto pss_sort = [](ProcessRecord& a, ProcessRecord& b) {
+        MemUsage stats_a = show_wss ? a.Wss() : a.Usage();
+        MemUsage stats_b = show_wss ? b.Wss() : b.Usage();
+        return reverse_sort ? stats_a.pss < stats_b.pss : stats_a.pss > stats_b.pss;
+    };
+
+    auto uss_sort = [](ProcessRecord& a, ProcessRecord& b) {
+        MemUsage stats_a = show_wss ? a.Wss() : a.Usage();
+        MemUsage stats_b = show_wss ? b.Wss() : b.Usage();
+        return reverse_sort ? stats_a.uss < stats_b.uss : stats_a.uss > stats_b.uss;
+    };
+
+    auto rss_sort = [](ProcessRecord& a, ProcessRecord& b) {
+        MemUsage stats_a = show_wss ? a.Wss() : a.Usage();
+        MemUsage stats_b = show_wss ? b.Wss() : b.Usage();
+        return reverse_sort ? stats_a.rss < stats_b.pss : stats_a.pss > stats_b.pss;
+    };
+
+    auto vss_sort = [](ProcessRecord& a, ProcessRecord& b) {
+        MemUsage stats_a = show_wss ? a.Wss() : a.Usage();
+        MemUsage stats_b = show_wss ? b.Wss() : b.Usage();
+        return reverse_sort ? stats_a.vss < stats_b.vss : stats_a.vss > stats_b.vss;
+    };
+
+    auto swap_sort = [](ProcessRecord& a, ProcessRecord& b) {
+        MemUsage stats_a = show_wss ? a.Wss() : a.Usage();
+        MemUsage stats_b = show_wss ? b.Wss() : b.Usage();
+        return reverse_sort ? stats_a.swap < stats_b.swap : stats_a.swap > stats_b.swap;
+    };
+
+    auto oomadj_sort = [](ProcessRecord& a, ProcessRecord& b) {
+        return reverse_sort ? a.oomadj() < b.oomadj() : a.oomadj() > b.oomadj();
+    };
+
+    // default PSS sort
+    std::function<bool(ProcessRecord & a, ProcessRecord & b)> proc_sort = pss_sort;
+
+    // count all pages by default
+    uint64_t pgflags = 0;
+    uint64_t pgflags_mask = 0;
+
+    int opt;
+    while ((opt = getopt(argc, argv, "cChkoprRsuvwW")) != -1) {
+        switch (opt) {
+            case 'c':
+                pgflags = 0;
+                pgflags_mask = (1 << KPF_SWAPBACKED);
+                break;
+            case 'C':
+                pgflags = (1 << KPF_SWAPBACKED);
+                pgflags_mask = (1 << KPF_SWAPBACKED);
+                break;
+            case 'h':
+                usage(argv[0]);
+                return 0;
+                break;
+            case 'k':
+                pgflags = (1 << KPF_KSM);
+                pgflags_mask = (1 << KPF_KSM);
+                break;
+            case 'o':
+                proc_sort = oomadj_sort;
+                show_oomadj = true;
+                break;
+            case 'p':
+                proc_sort = pss_sort;
+                break;
+            case 'r':
+                proc_sort = rss_sort;
+                break;
+            case 'R':
+                reverse_sort = true;
+                break;
+            case 's':
+                proc_sort = swap_sort;
+                break;
+            case 'u':
+                proc_sort = uss_sort;
+                break;
+            case 'v':
+                proc_sort = vss_sort;
+                break;
+            case 'w':
+                show_wss = true;
+                break;
+            case 'W':
+                reset_wss = true;
+                break;
+            default:
+                abort();
+        }
+    }
+
+    std::vector<pid_t> pids;
+    std::vector<ProcessRecord> procs;
+    if (reset_wss) {
+        if (!read_all_pids(&pids,
+                           [&](pid_t pid) -> bool { return ProcMemInfo::ResetWorkingSet(pid); })) {
+            std::cerr << "Failed to reset working set of all processes" << std::endl;
+            exit(EXIT_FAILURE);
+        }
+        // we are done, all other options passed to procrank are ignored in the presence of '-W'
+        return 0;
+    }
+
+    ::android::meminfo::SysMemInfo smi;
+    if (!smi.ReadMemInfo()) {
+        std::cerr << "Failed to get system memory info" << std::endl;
+        exit(EXIT_FAILURE);
+    }
+
+    // Figure out swap and zram
+    uint64_t swap_total = smi.mem_swap_kb() * 1024;
+    has_swap = swap_total > 0;
+    // Allocate the swap array
+    auto swap_offset_array = std::make_unique<uint16_t[]>(swap_total / getpagesize());
+    if (has_swap) {
+        has_zram = smi.mem_zram_kb() > 0;
+        if (has_zram) {
+            zram_compression_ratio = static_cast<float>(smi.mem_zram_kb()) /
+                                     (smi.mem_swap_kb() - smi.mem_swap_free_kb());
+        }
+    }
+
+    auto mark_swap_usage = [&](pid_t pid) -> bool {
+        ProcessRecord proc(pid, show_wss, pgflags, pgflags_mask);
+        if (!proc.valid()) {
+            std::cerr << "Failed to create process record for: " << pid << std::endl;
+            return false;
+        }
+
+        // Skip processes with no memory mappings
+        uint64_t vss = show_wss ? proc.Wss().vss : proc.Usage().vss;
+        if (vss == 0) return true;
+
+        // collect swap_offset counts from all processes in 1st pass
+        if (!show_wss && has_swap &&
+            !count_swap_offsets(proc, swap_offset_array.get(), swap_total / getpagesize())) {
+            std::cerr << "Failed to count swap offsets for process: " << pid << std::endl;
+            return false;
+        }
+
+        procs.push_back(std::move(proc));
+        return true;
+    };
+
+    // Get a list of all pids currently running in the system in
+    // 1st pass through all processes. Mark each swap offset used by the process as we find them
+    // for calculating proportional swap usage later.
+    if (!read_all_pids(&pids, mark_swap_usage)) {
+        std::cerr << "Failed to read all pids from the system" << std::endl;
+        exit(EXIT_FAILURE);
+    }
+
+    std::stringstream ss;
+    if (procs.empty()) {
+        // This would happen in corner cases where procrank is being run to find KSM usage on a
+        // system with no KSM and combined with working set determination as follows
+        //   procrank -w -u -k
+        //   procrank -w -s -k
+        //   procrank -w -o -k
+        ss << "<empty>" << std::endl << std::endl;
+        print_sysmeminfo(ss, smi);
+        ss << std::endl;
+        std::cout << ss.str();
+        return 0;
+    }
+
+    // Sort all process records, default is PSS descending
+    std::sort(procs.begin(), procs.end(), proc_sort);
+
+    // start dumping output in string stream
+    print_header(ss);
+    ss << std::endl;
+
+    // 2nd pass to calculate and get per process stats to add them up
+    print_processes(ss, procs, swap_offset_array.get());
+
+    // Add separator to output
+    print_separator(ss);
+    ss << std::endl;
+
+    // Add totals to output
+    print_totals(ss);
+    ss << std::endl << std::endl;
+
+    // Add system information at the end
+    print_sysmeminfo(ss, smi);
+    ss << std::endl;
+
+    // dump on the screen
+    std::cout << ss.str();
+
+    return 0;
+}
diff --git a/libprocinfo/include/procinfo/process_map.h b/libprocinfo/include/procinfo/process_map.h
index 0fc4201..981241e 100644
--- a/libprocinfo/include/procinfo/process_map.h
+++ b/libprocinfo/include/procinfo/process_map.h
@@ -17,6 +17,7 @@
 #pragma once
 
 #include <stdlib.h>
+#include <string.h>
 #include <sys/mman.h>
 #include <sys/types.h>
 
diff --git a/libstats/include/stats_event_list.h b/libstats/include/stats_event_list.h
index a9832db..41ca79b 100644
--- a/libstats/include/stats_event_list.h
+++ b/libstats/include/stats_event_list.h
@@ -26,7 +26,7 @@
 int write_to_logger(android_log_context context, log_id_t id);
 void note_log_drop();
 void stats_log_close();
-
+int android_log_write_char_array(android_log_context ctx, const char* value, size_t len);
 #ifdef __cplusplus
 }
 #endif
@@ -244,6 +244,14 @@
         return ret >= 0;
     }
 
+    bool AppendCharArray(const char* value, size_t len) {
+        int retval = android_log_write_char_array(ctx, value, len);
+        if (retval < 0) {
+            ret = retval;
+        }
+        return ret >= 0;
+    }
+
     android_log_list_element read() { return android_log_read_next(ctx); }
     android_log_list_element peek() { return android_log_peek_next(ctx); }
 };
diff --git a/libstats/stats_event_list.c b/libstats/stats_event_list.c
index 72770d4..f4a7e94 100644
--- a/libstats/stats_event_list.c
+++ b/libstats/stats_event_list.c
@@ -193,3 +193,47 @@
     errno = save_errno;
     return ret;
 }
+
+static inline void copy4LE(uint8_t* buf, uint32_t val) {
+    buf[0] = val & 0xFF;
+    buf[1] = (val >> 8) & 0xFF;
+    buf[2] = (val >> 16) & 0xFF;
+    buf[3] = (val >> 24) & 0xFF;
+}
+
+// Note: this function differs from android_log_write_string8_len in that the length passed in
+// should be treated as actual length and not max length.
+int android_log_write_char_array(android_log_context ctx, const char* value, size_t actual_len) {
+    size_t needed;
+    ssize_t len = actual_len;
+    android_log_context_internal* context;
+
+    context = (android_log_context_internal*)ctx;
+    if (!context || (kAndroidLoggerWrite != context->read_write_flag)) {
+        return -EBADF;
+    }
+    if (context->overflow) {
+        return -EIO;
+    }
+    if (!value) {
+        value = "";
+        len = 0;
+    }
+    needed = sizeof(uint8_t) + sizeof(int32_t) + len;
+    if ((context->pos + needed) > MAX_EVENT_PAYLOAD) {
+        /* Truncate string for delivery */
+        len = MAX_EVENT_PAYLOAD - context->pos - 1 - sizeof(int32_t);
+        if (len <= 0) {
+            context->overflow = true;
+            return -EIO;
+        }
+    }
+    context->count[context->list_nest_depth]++;
+    context->storage[context->pos + 0] = EVENT_TYPE_STRING;
+    copy4LE(&context->storage[context->pos + 1], len);
+    if (len) {
+        memcpy(&context->storage[context->pos + 5], value, len);
+    }
+    context->pos += needed;
+    return len;
+}
diff --git a/libsysutils/Android.bp b/libsysutils/Android.bp
index 29d23c8..da5d86c 100644
--- a/libsysutils/Android.bp
+++ b/libsysutils/Android.bp
@@ -1,4 +1,4 @@
-cc_library_shared {
+cc_library {
     name: "libsysutils",
     vendor_available: true,
     vndk: {
diff --git a/libunwindstack/Elf.cpp b/libunwindstack/Elf.cpp
index 4d72ead..5b586a2 100644
--- a/libunwindstack/Elf.cpp
+++ b/libunwindstack/Elf.cpp
@@ -140,6 +140,10 @@
   return true;
 }
 
+bool Elf::GetBuildID(std::string* build_id) {
+  return valid_ && interface_->GetBuildID(build_id);
+}
+
 void Elf::GetLastError(ErrorData* data) {
   if (valid_) {
     *data = interface_->last_error();
diff --git a/libunwindstack/ElfInterface.cpp b/libunwindstack/ElfInterface.cpp
index f59a472..d0af94a 100644
--- a/libunwindstack/ElfInterface.cpp
+++ b/libunwindstack/ElfInterface.cpp
@@ -237,6 +237,56 @@
   }
 }
 
+template <typename NhdrType>
+bool ElfInterface::ReadBuildID(std::string* build_id) {
+  // Ensure there is no overflow in any of the calulations below.
+  uint64_t tmp;
+  if (__builtin_add_overflow(gnu_build_id_offset_, gnu_build_id_size_, &tmp)) {
+    return false;
+  }
+
+  uint64_t offset = 0;
+  while (offset < gnu_build_id_size_) {
+    if (gnu_build_id_size_ - offset < sizeof(NhdrType)) {
+      return false;
+    }
+    NhdrType hdr;
+    if (!memory_->ReadFully(gnu_build_id_offset_ + offset, &hdr, sizeof(hdr))) {
+      return false;
+    }
+    offset += sizeof(hdr);
+
+    if (gnu_build_id_size_ - offset < hdr.n_namesz) {
+      return false;
+    }
+    if (hdr.n_namesz > 0) {
+      std::string name(hdr.n_namesz, '\0');
+      if (!memory_->ReadFully(gnu_build_id_offset_ + offset, &(name[0]), hdr.n_namesz)) {
+        return false;
+      }
+
+      // Trim trailing \0 as GNU is stored as a C string in the ELF file.
+      if (name.back() == '\0')
+        name.resize(name.size() - 1);
+
+      // Align hdr.n_namesz to next power multiple of 4. See man 5 elf.
+      offset += (hdr.n_namesz + 3) & ~3;
+
+      if (name == "GNU" && hdr.n_type == NT_GNU_BUILD_ID) {
+        if (gnu_build_id_size_ - offset < hdr.n_descsz) {
+          return false;
+        }
+        build_id->resize(hdr.n_descsz);
+        return memory_->ReadFully(gnu_build_id_offset_ + offset, &(*build_id)[0],
+                                  hdr.n_descsz);
+      }
+    }
+    // Align hdr.n_descsz to next power multiple of 4. See man 5 elf.
+    offset += (hdr.n_descsz + 3) & ~3;
+  }
+  return false;
+}
+
 template <typename EhdrType, typename ShdrType>
 void ElfInterface::ReadSectionHeaders(const EhdrType& ehdr) {
   uint64_t offset = ehdr.e_shoff;
@@ -308,6 +358,15 @@
       // In order to read soname, keep track of address to offset mapping.
       strtabs_.push_back(std::make_pair<uint64_t, uint64_t>(static_cast<uint64_t>(shdr.sh_addr),
                                                             static_cast<uint64_t>(shdr.sh_offset)));
+    } else if (shdr.sh_type == SHT_NOTE) {
+      if (shdr.sh_name < sec_size) {
+        std::string name;
+        if (memory_->ReadString(sec_offset + shdr.sh_name, &name) &&
+            name == ".note.gnu.build-id") {
+          gnu_build_id_offset_ = shdr.sh_offset;
+          gnu_build_id_size_ = shdr.sh_size;
+        }
+      }
     }
   }
 }
@@ -492,6 +551,9 @@
 template void ElfInterface::ReadSectionHeaders<Elf32_Ehdr, Elf32_Shdr>(const Elf32_Ehdr&);
 template void ElfInterface::ReadSectionHeaders<Elf64_Ehdr, Elf64_Shdr>(const Elf64_Ehdr&);
 
+template bool ElfInterface::ReadBuildID<Elf32_Nhdr>(std::string*);
+template bool ElfInterface::ReadBuildID<Elf64_Nhdr>(std::string*);
+
 template bool ElfInterface::GetSonameWithTemplate<Elf32_Dyn>(std::string*);
 template bool ElfInterface::GetSonameWithTemplate<Elf64_Dyn>(std::string*);
 
diff --git a/libunwindstack/Global.cpp b/libunwindstack/Global.cpp
index 7a3de01..fdfd705 100644
--- a/libunwindstack/Global.cpp
+++ b/libunwindstack/Global.cpp
@@ -15,6 +15,7 @@
  */
 
 #include <stdint.h>
+#include <string.h>
 #include <sys/mman.h>
 
 #include <string>
diff --git a/libunwindstack/Maps.cpp b/libunwindstack/Maps.cpp
index 8729871..a9fb859 100644
--- a/libunwindstack/Maps.cpp
+++ b/libunwindstack/Maps.cpp
@@ -19,6 +19,7 @@
 #include <inttypes.h>
 #include <stdint.h>
 #include <stdio.h>
+#include <string.h>
 #include <sys/mman.h>
 #include <sys/types.h>
 #include <unistd.h>
diff --git a/libunwindstack/Memory.cpp b/libunwindstack/Memory.cpp
index a30d65e..9904fef 100644
--- a/libunwindstack/Memory.cpp
+++ b/libunwindstack/Memory.cpp
@@ -16,6 +16,7 @@
 
 #include <errno.h>
 #include <fcntl.h>
+#include <string.h>
 #include <sys/mman.h>
 #include <sys/ptrace.h>
 #include <sys/stat.h>
diff --git a/libunwindstack/RegsArm.cpp b/libunwindstack/RegsArm.cpp
index de22bde..885dc94 100644
--- a/libunwindstack/RegsArm.cpp
+++ b/libunwindstack/RegsArm.cpp
@@ -15,6 +15,7 @@
  */
 
 #include <stdint.h>
+#include <string.h>
 
 #include <functional>
 
diff --git a/libunwindstack/RegsArm64.cpp b/libunwindstack/RegsArm64.cpp
index a68f6e0..e9787aa 100644
--- a/libunwindstack/RegsArm64.cpp
+++ b/libunwindstack/RegsArm64.cpp
@@ -15,6 +15,7 @@
  */
 
 #include <stdint.h>
+#include <string.h>
 
 #include <functional>
 
diff --git a/libunwindstack/RegsMips.cpp b/libunwindstack/RegsMips.cpp
index 2e6908c..14a4e31 100644
--- a/libunwindstack/RegsMips.cpp
+++ b/libunwindstack/RegsMips.cpp
@@ -15,6 +15,7 @@
  */
 
 #include <stdint.h>
+#include <string.h>
 
 #include <functional>
 
diff --git a/libunwindstack/RegsMips64.cpp b/libunwindstack/RegsMips64.cpp
index 0b835a1..3f67d92 100644
--- a/libunwindstack/RegsMips64.cpp
+++ b/libunwindstack/RegsMips64.cpp
@@ -15,6 +15,7 @@
  */
 
 #include <stdint.h>
+#include <string.h>
 
 #include <functional>
 
diff --git a/libunwindstack/RegsX86_64.cpp b/libunwindstack/RegsX86_64.cpp
index ebad3f4..74cd1cb 100644
--- a/libunwindstack/RegsX86_64.cpp
+++ b/libunwindstack/RegsX86_64.cpp
@@ -15,6 +15,7 @@
  */
 
 #include <stdint.h>
+#include <string.h>
 
 #include <functional>
 
diff --git a/libunwindstack/Symbols.cpp b/libunwindstack/Symbols.cpp
index 14ebdbb..e3c15a2 100644
--- a/libunwindstack/Symbols.cpp
+++ b/libunwindstack/Symbols.cpp
@@ -17,6 +17,7 @@
 #include <elf.h>
 #include <stdint.h>
 
+#include <algorithm>
 #include <string>
 
 #include <unwindstack/Memory.h>
diff --git a/libunwindstack/include/unwindstack/Elf.h b/libunwindstack/include/unwindstack/Elf.h
index e5b0a89..27f7201 100644
--- a/libunwindstack/include/unwindstack/Elf.h
+++ b/libunwindstack/include/unwindstack/Elf.h
@@ -65,6 +65,8 @@
 
   bool GetGlobalVariable(const std::string& name, uint64_t* memory_address);
 
+  bool GetBuildID(std::string* build_id);
+
   uint64_t GetRelPc(uint64_t pc, const MapInfo* map_info);
 
   bool Step(uint64_t rel_pc, uint64_t adjusted_rel_pc, Regs* regs, Memory* process_memory,
diff --git a/libunwindstack/include/unwindstack/ElfInterface.h b/libunwindstack/include/unwindstack/ElfInterface.h
index a45eba8..52992d9 100644
--- a/libunwindstack/include/unwindstack/ElfInterface.h
+++ b/libunwindstack/include/unwindstack/ElfInterface.h
@@ -62,6 +62,8 @@
 
   virtual bool GetGlobalVariable(const std::string& name, uint64_t* memory_address) = 0;
 
+  virtual bool GetBuildID(std::string* build_id) = 0;
+
   virtual bool Step(uint64_t rel_pc, Regs* regs, Memory* process_memory, bool* finished);
 
   virtual bool IsValidPc(uint64_t pc);
@@ -85,6 +87,8 @@
   uint64_t debug_frame_size() { return debug_frame_size_; }
   uint64_t gnu_debugdata_offset() { return gnu_debugdata_offset_; }
   uint64_t gnu_debugdata_size() { return gnu_debugdata_size_; }
+  uint64_t gnu_build_id_offset() { return gnu_build_id_offset_; }
+  uint64_t gnu_build_id_size() { return gnu_build_id_size_; }
 
   DwarfSection* eh_frame() { return eh_frame_.get(); }
   DwarfSection* debug_frame() { return debug_frame_.get(); }
@@ -123,6 +127,9 @@
   template <typename EhdrType>
   static void GetMaxSizeWithTemplate(Memory* memory, uint64_t* size);
 
+  template <typename NhdrType>
+  bool ReadBuildID(std::string* build_id);
+
   Memory* memory_;
   std::unordered_map<uint64_t, LoadInfo> pt_loads_;
 
@@ -143,6 +150,9 @@
   uint64_t gnu_debugdata_offset_ = 0;
   uint64_t gnu_debugdata_size_ = 0;
 
+  uint64_t gnu_build_id_offset_ = 0;
+  uint64_t gnu_build_id_size_ = 0;
+
   uint8_t soname_type_ = SONAME_UNKNOWN;
   std::string soname_;
 
@@ -182,6 +192,10 @@
     return ElfInterface::GetGlobalVariableWithTemplate<Elf32_Sym>(name, memory_address);
   }
 
+  bool GetBuildID(std::string* build_id) {
+    return ElfInterface::ReadBuildID<Elf32_Nhdr>(build_id);
+  }
+
   static void GetMaxSize(Memory* memory, uint64_t* size) {
     GetMaxSizeWithTemplate<Elf32_Ehdr>(memory, size);
   }
@@ -212,6 +226,10 @@
     return ElfInterface::GetGlobalVariableWithTemplate<Elf64_Sym>(name, memory_address);
   }
 
+  bool GetBuildID(std::string* build_id) {
+    return ElfInterface::ReadBuildID<Elf64_Nhdr>(build_id);
+  }
+
   static void GetMaxSize(Memory* memory, uint64_t* size) {
     GetMaxSizeWithTemplate<Elf64_Ehdr>(memory, size);
   }
diff --git a/libunwindstack/tests/ElfFake.h b/libunwindstack/tests/ElfFake.h
index a3bf5ce..c2bd0f6 100644
--- a/libunwindstack/tests/ElfFake.h
+++ b/libunwindstack/tests/ElfFake.h
@@ -72,6 +72,9 @@
 
   bool GetFunctionName(uint64_t, std::string*, uint64_t*) override;
   bool GetGlobalVariable(const std::string&, uint64_t*) override;
+  bool GetBuildID(std::string*) override {
+    return false;
+  }
 
   bool Step(uint64_t, Regs*, Memory*, bool*) override;
 
diff --git a/libunwindstack/tests/ElfInterfaceTest.cpp b/libunwindstack/tests/ElfInterfaceTest.cpp
index 9326bff..6023dc4 100644
--- a/libunwindstack/tests/ElfInterfaceTest.cpp
+++ b/libunwindstack/tests/ElfInterfaceTest.cpp
@@ -116,6 +116,21 @@
   void InitSym(uint64_t offset, uint32_t value, uint32_t size, uint32_t name_offset,
                uint64_t sym_offset, const char* name);
 
+  template <typename Ehdr, typename Shdr, typename Nhdr, typename ElfInterfaceType>
+  void BuildID();
+
+  template <typename Ehdr, typename Shdr, typename Nhdr, typename ElfInterfaceType>
+  void BuildIDTwoNotes();
+
+  template <typename Ehdr, typename Shdr, typename Nhdr, typename ElfInterfaceType>
+  void BuildIDSectionTooSmallForName();
+
+  template <typename Ehdr, typename Shdr, typename Nhdr, typename ElfInterfaceType>
+  void BuildIDSectionTooSmallForDesc();
+
+  template <typename Ehdr, typename Shdr, typename Nhdr, typename ElfInterfaceType>
+  void BuildIDSectionTooSmallForHeader();
+
   MemoryFake memory_;
 };
 
@@ -898,7 +913,7 @@
 
   Ehdr ehdr = {};
   ehdr.e_shoff = offset;
-  ehdr.e_shnum = 6;
+  ehdr.e_shnum = 7;
   ehdr.e_shentsize = sizeof(Shdr);
   ehdr.e_shstrndx = 2;
   memory_.SetMemory(0, &ehdr, sizeof(ehdr));
@@ -958,10 +973,19 @@
   memory_.SetMemory(offset, &shdr, sizeof(shdr));
   offset += ehdr.e_shentsize;
 
+  memset(&shdr, 0, sizeof(shdr));
+  shdr.sh_type = SHT_NOTE;
+  shdr.sh_name = 0x500;
+  shdr.sh_offset = 0xb000;
+  shdr.sh_size = 0xf00;
+  memory_.SetMemory(offset, &shdr, sizeof(shdr));
+  offset += ehdr.e_shentsize;
+
   memory_.SetMemory(0xf100, ".debug_frame", sizeof(".debug_frame"));
   memory_.SetMemory(0xf200, ".gnu_debugdata", sizeof(".gnu_debugdata"));
   memory_.SetMemory(0xf300, ".eh_frame", sizeof(".eh_frame"));
   memory_.SetMemory(0xf400, ".eh_frame_hdr", sizeof(".eh_frame_hdr"));
+  memory_.SetMemory(0xf500, ".note.gnu.build-id", sizeof(".note.gnu.build-id"));
 
   uint64_t load_bias = 0;
   ASSERT_TRUE(elf->Init(&load_bias));
@@ -974,6 +998,8 @@
   EXPECT_EQ(0x800U, elf->eh_frame_size());
   EXPECT_EQ(0xa000U, elf->eh_frame_hdr_offset());
   EXPECT_EQ(0xf00U, elf->eh_frame_hdr_size());
+  EXPECT_EQ(0xb000U, elf->gnu_build_id_offset());
+  EXPECT_EQ(0xf00U, elf->gnu_build_id_size());
 }
 
 TEST_F(ElfInterfaceTest, init_section_headers_offsets32) {
@@ -1153,4 +1179,321 @@
   EXPECT_FALSE(elf->IsValidPc(0x2a00));
 }
 
+template <typename Ehdr, typename Shdr, typename Nhdr, typename ElfInterfaceType>
+void ElfInterfaceTest::BuildID() {
+  std::unique_ptr<ElfInterfaceType> elf(new ElfInterfaceType(&memory_));
+
+  uint64_t offset = 0x2000;
+
+  Ehdr ehdr = {};
+  ehdr.e_shoff = offset;
+  ehdr.e_shnum = 3;
+  ehdr.e_shentsize = sizeof(Shdr);
+  ehdr.e_shstrndx = 2;
+  memory_.SetMemory(0, &ehdr, sizeof(ehdr));
+
+  offset += ehdr.e_shentsize;
+
+  char note_section[128];
+  Nhdr note_header = {};
+  note_header.n_namesz = 4;  // "GNU"
+  note_header.n_descsz = 8; // "BUILDID"
+  note_header.n_type = NT_GNU_BUILD_ID;
+  memcpy(&note_section, &note_header, sizeof(note_header));
+  size_t note_offset = sizeof(note_header);
+  memcpy(&note_section[note_offset], "GNU", sizeof("GNU"));
+  note_offset += sizeof("GNU");
+  memcpy(&note_section[note_offset], "BUILDID", sizeof("BUILDID"));
+  note_offset += sizeof("BUILDID");
+
+  Shdr shdr = {};
+  shdr.sh_type = SHT_NOTE;
+  shdr.sh_name = 0x500;
+  shdr.sh_offset = 0xb000;
+  shdr.sh_size = sizeof(note_section);
+  memory_.SetMemory(offset, &shdr, sizeof(shdr));
+  offset += ehdr.e_shentsize;
+
+  // The string data for section header names.
+  memset(&shdr, 0, sizeof(shdr));
+  shdr.sh_type = SHT_STRTAB;
+  shdr.sh_name = 0x20000;
+  shdr.sh_offset = 0xf000;
+  shdr.sh_size = 0x1000;
+  memory_.SetMemory(offset, &shdr, sizeof(shdr));
+  offset += ehdr.e_shentsize;
+
+  memory_.SetMemory(0xf500, ".note.gnu.build-id", sizeof(".note.gnu.build-id"));
+  memory_.SetMemory(0xb000, note_section, sizeof(note_section));
+
+  uint64_t load_bias = 0;
+  ASSERT_TRUE(elf->Init(&load_bias));
+  std::string build_id;
+  ASSERT_TRUE(elf->GetBuildID(&build_id));
+  EXPECT_STREQ(build_id.c_str(), "BUILDID");
+}
+
+template <typename Ehdr, typename Shdr, typename Nhdr, typename ElfInterfaceType>
+void ElfInterfaceTest::BuildIDTwoNotes() {
+  std::unique_ptr<ElfInterfaceType> elf(new ElfInterfaceType(&memory_));
+
+  uint64_t offset = 0x2000;
+
+  Ehdr ehdr = {};
+  ehdr.e_shoff = offset;
+  ehdr.e_shnum = 3;
+  ehdr.e_shentsize = sizeof(Shdr);
+  ehdr.e_shstrndx = 2;
+  memory_.SetMemory(0, &ehdr, sizeof(ehdr));
+
+  offset += ehdr.e_shentsize;
+
+  char note_section[128];
+  Nhdr note_header = {};
+  note_header.n_namesz = 8;  // "WRONG" aligned to 4
+  note_header.n_descsz = 8; // "BUILDID"
+  note_header.n_type = NT_GNU_BUILD_ID;
+  memcpy(&note_section, &note_header, sizeof(note_header));
+  size_t note_offset = sizeof(note_header);
+  memcpy(&note_section[note_offset], "WRONG", sizeof("WRONG"));
+  note_offset += 8;
+  memcpy(&note_section[note_offset], "BUILDID", sizeof("BUILDID"));
+  note_offset += sizeof("BUILDID");
+
+  note_header.n_namesz = 4;  // "GNU"
+  note_header.n_descsz = 8; // "BUILDID"
+  note_header.n_type = NT_GNU_BUILD_ID;
+  memcpy(&note_section[note_offset], &note_header, sizeof(note_header));
+  note_offset += sizeof(note_header);
+  memcpy(&note_section[note_offset], "GNU", sizeof("GNU"));
+  note_offset += sizeof("GNU");
+  memcpy(&note_section[note_offset], "BUILDID", sizeof("BUILDID"));
+  note_offset += sizeof("BUILDID");
+
+  Shdr shdr = {};
+  shdr.sh_type = SHT_NOTE;
+  shdr.sh_name = 0x500;
+  shdr.sh_offset = 0xb000;
+  shdr.sh_size = sizeof(note_section);
+  memory_.SetMemory(offset, &shdr, sizeof(shdr));
+  offset += ehdr.e_shentsize;
+
+  // The string data for section header names.
+  memset(&shdr, 0, sizeof(shdr));
+  shdr.sh_type = SHT_STRTAB;
+  shdr.sh_name = 0x20000;
+  shdr.sh_offset = 0xf000;
+  shdr.sh_size = 0x1000;
+  memory_.SetMemory(offset, &shdr, sizeof(shdr));
+  offset += ehdr.e_shentsize;
+
+  memory_.SetMemory(0xf500, ".note.gnu.build-id", sizeof(".note.gnu.build-id"));
+  memory_.SetMemory(0xb000, note_section, sizeof(note_section));
+
+  uint64_t load_bias = 0;
+  ASSERT_TRUE(elf->Init(&load_bias));
+  std::string build_id;
+  ASSERT_TRUE(elf->GetBuildID(&build_id));
+  EXPECT_STREQ(build_id.c_str(), "BUILDID");
+}
+
+template <typename Ehdr, typename Shdr, typename Nhdr, typename ElfInterfaceType>
+void ElfInterfaceTest::BuildIDSectionTooSmallForName () {
+  std::unique_ptr<ElfInterfaceType> elf(new ElfInterfaceType(&memory_));
+
+  uint64_t offset = 0x2000;
+
+  Ehdr ehdr = {};
+  ehdr.e_shoff = offset;
+  ehdr.e_shnum = 3;
+  ehdr.e_shentsize = sizeof(Shdr);
+  ehdr.e_shstrndx = 2;
+  memory_.SetMemory(0, &ehdr, sizeof(ehdr));
+
+  offset += ehdr.e_shentsize;
+
+  char note_section[128];
+  Nhdr note_header = {};
+  note_header.n_namesz = 4;  // "GNU"
+  note_header.n_descsz = 8; // "BUILDID"
+  note_header.n_type = NT_GNU_BUILD_ID;
+  memcpy(&note_section, &note_header, sizeof(note_header));
+  size_t note_offset = sizeof(note_header);
+  memcpy(&note_section[note_offset], "GNU", sizeof("GNU"));
+  note_offset += sizeof("GNU");
+  memcpy(&note_section[note_offset], "BUILDID", sizeof("BUILDID"));
+  note_offset += sizeof("BUILDID");
+
+  Shdr shdr = {};
+  shdr.sh_type = SHT_NOTE;
+  shdr.sh_name = 0x500;
+  shdr.sh_offset = 0xb000;
+  shdr.sh_size = sizeof(note_header) + 1;
+  memory_.SetMemory(offset, &shdr, sizeof(shdr));
+  offset += ehdr.e_shentsize;
+
+  // The string data for section header names.
+  memset(&shdr, 0, sizeof(shdr));
+  shdr.sh_type = SHT_STRTAB;
+  shdr.sh_name = 0x20000;
+  shdr.sh_offset = 0xf000;
+  shdr.sh_size = 0x1000;
+  memory_.SetMemory(offset, &shdr, sizeof(shdr));
+  offset += ehdr.e_shentsize;
+
+  memory_.SetMemory(0xf500, ".note.gnu.build-id", sizeof(".note.gnu.build-id"));
+  memory_.SetMemory(0xb000, note_section, sizeof(note_section));
+
+  uint64_t load_bias = 0;
+  ASSERT_TRUE(elf->Init(&load_bias));
+  std::string build_id;
+  ASSERT_FALSE(elf->GetBuildID(&build_id));
+}
+
+template <typename Ehdr, typename Shdr, typename Nhdr, typename ElfInterfaceType>
+void ElfInterfaceTest::BuildIDSectionTooSmallForDesc () {
+  std::unique_ptr<ElfInterfaceType> elf(new ElfInterfaceType(&memory_));
+
+  uint64_t offset = 0x2000;
+
+  Ehdr ehdr = {};
+  ehdr.e_shoff = offset;
+  ehdr.e_shnum = 3;
+  ehdr.e_shentsize = sizeof(Shdr);
+  ehdr.e_shstrndx = 2;
+  memory_.SetMemory(0, &ehdr, sizeof(ehdr));
+
+  offset += ehdr.e_shentsize;
+
+  char note_section[128];
+  Nhdr note_header = {};
+  note_header.n_namesz = 4;  // "GNU"
+  note_header.n_descsz = 8; // "BUILDID"
+  note_header.n_type = NT_GNU_BUILD_ID;
+  memcpy(&note_section, &note_header, sizeof(note_header));
+  size_t note_offset = sizeof(note_header);
+  memcpy(&note_section[note_offset], "GNU", sizeof("GNU"));
+  note_offset += sizeof("GNU");
+  memcpy(&note_section[note_offset], "BUILDID", sizeof("BUILDID"));
+  note_offset += sizeof("BUILDID");
+
+  Shdr shdr = {};
+  shdr.sh_type = SHT_NOTE;
+  shdr.sh_name = 0x500;
+  shdr.sh_offset = 0xb000;
+  shdr.sh_size = sizeof(note_header) + sizeof("GNU") + 1;
+  memory_.SetMemory(offset, &shdr, sizeof(shdr));
+  offset += ehdr.e_shentsize;
+
+  // The string data for section header names.
+  memset(&shdr, 0, sizeof(shdr));
+  shdr.sh_type = SHT_STRTAB;
+  shdr.sh_name = 0x20000;
+  shdr.sh_offset = 0xf000;
+  shdr.sh_size = 0x1000;
+  memory_.SetMemory(offset, &shdr, sizeof(shdr));
+  offset += ehdr.e_shentsize;
+
+  memory_.SetMemory(0xf500, ".note.gnu.build-id", sizeof(".note.gnu.build-id"));
+  memory_.SetMemory(0xb000, note_section, sizeof(note_section));
+
+  uint64_t load_bias = 0;
+  ASSERT_TRUE(elf->Init(&load_bias));
+  std::string build_id;
+  ASSERT_FALSE(elf->GetBuildID(&build_id));
+}
+
+template <typename Ehdr, typename Shdr, typename Nhdr, typename ElfInterfaceType>
+void ElfInterfaceTest::BuildIDSectionTooSmallForHeader () {
+  std::unique_ptr<ElfInterfaceType> elf(new ElfInterfaceType(&memory_));
+
+  uint64_t offset = 0x2000;
+
+  Ehdr ehdr = {};
+  ehdr.e_shoff = offset;
+  ehdr.e_shnum = 3;
+  ehdr.e_shentsize = sizeof(Shdr);
+  ehdr.e_shstrndx = 2;
+  memory_.SetMemory(0, &ehdr, sizeof(ehdr));
+
+  offset += ehdr.e_shentsize;
+
+  char note_section[128];
+  Nhdr note_header = {};
+  note_header.n_namesz = 4;  // "GNU"
+  note_header.n_descsz = 8; // "BUILDID"
+  note_header.n_type = NT_GNU_BUILD_ID;
+  memcpy(&note_section, &note_header, sizeof(note_header));
+  size_t note_offset = sizeof(note_header);
+  memcpy(&note_section[note_offset], "GNU", sizeof("GNU"));
+  note_offset += sizeof("GNU");
+  memcpy(&note_section[note_offset], "BUILDID", sizeof("BUILDID"));
+  note_offset += sizeof("BUILDID");
+
+  Shdr shdr = {};
+  shdr.sh_type = SHT_NOTE;
+  shdr.sh_name = 0x500;
+  shdr.sh_offset = 0xb000;
+  shdr.sh_size = sizeof(note_header) - 1;
+  memory_.SetMemory(offset, &shdr, sizeof(shdr));
+  offset += ehdr.e_shentsize;
+
+  // The string data for section header names.
+  memset(&shdr, 0, sizeof(shdr));
+  shdr.sh_type = SHT_STRTAB;
+  shdr.sh_name = 0x20000;
+  shdr.sh_offset = 0xf000;
+  shdr.sh_size = 0x1000;
+  memory_.SetMemory(offset, &shdr, sizeof(shdr));
+  offset += ehdr.e_shentsize;
+
+  memory_.SetMemory(0xf500, ".note.gnu.build-id", sizeof(".note.gnu.build-id"));
+  memory_.SetMemory(0xb000, note_section, sizeof(note_section));
+
+  uint64_t load_bias = 0;
+  ASSERT_TRUE(elf->Init(&load_bias));
+  std::string build_id;
+  ASSERT_FALSE(elf->GetBuildID(&build_id));
+}
+
+TEST_F(ElfInterfaceTest, build_id32) {
+  BuildID<Elf32_Ehdr, Elf32_Shdr, Elf32_Nhdr, ElfInterface32>();
+}
+
+TEST_F(ElfInterfaceTest, build_id64) {
+  BuildID<Elf64_Ehdr, Elf64_Shdr, Elf64_Nhdr, ElfInterface64>();
+}
+
+TEST_F(ElfInterfaceTest, build_id_two_notes32) {
+  BuildIDTwoNotes<Elf32_Ehdr, Elf32_Shdr, Elf32_Nhdr, ElfInterface32>();
+}
+
+TEST_F(ElfInterfaceTest, build_id_two_notes64) {
+  BuildIDTwoNotes<Elf64_Ehdr, Elf64_Shdr, Elf64_Nhdr, ElfInterface64>();
+}
+
+TEST_F(ElfInterfaceTest, build_id_section_too_small_for_name32) {
+  BuildIDSectionTooSmallForName<Elf32_Ehdr, Elf32_Shdr, Elf32_Nhdr, ElfInterface32>();
+}
+
+TEST_F(ElfInterfaceTest, build_id_section_too_small_for_name64) {
+  BuildIDSectionTooSmallForName<Elf64_Ehdr, Elf64_Shdr, Elf64_Nhdr, ElfInterface64>();
+}
+
+TEST_F(ElfInterfaceTest, build_id_section_too_small_for_desc32) {
+  BuildIDSectionTooSmallForDesc<Elf32_Ehdr, Elf32_Shdr, Elf32_Nhdr, ElfInterface32>();
+}
+
+TEST_F(ElfInterfaceTest, build_id_section_too_small_for_desc64) {
+  BuildIDSectionTooSmallForDesc<Elf64_Ehdr, Elf64_Shdr, Elf64_Nhdr, ElfInterface64>();
+}
+
+TEST_F(ElfInterfaceTest, build_id_section_too_small_for_header32) {
+  BuildIDSectionTooSmallForHeader<Elf32_Ehdr, Elf32_Shdr, Elf32_Nhdr, ElfInterface32>();
+}
+
+TEST_F(ElfInterfaceTest, build_id_section_too_small_for_header64) {
+  BuildIDSectionTooSmallForHeader<Elf64_Ehdr, Elf64_Shdr, Elf64_Nhdr, ElfInterface64>();
+}
+
 }  // namespace unwindstack
diff --git a/libunwindstack/tests/ElfTest.cpp b/libunwindstack/tests/ElfTest.cpp
index ccf8927..7766218 100644
--- a/libunwindstack/tests/ElfTest.cpp
+++ b/libunwindstack/tests/ElfTest.cpp
@@ -311,6 +311,7 @@
   void InitHeaders(uint64_t) override {}
   bool GetSoname(std::string*) override { return false; }
   bool GetFunctionName(uint64_t, std::string*, uint64_t*) override { return false; }
+  bool GetBuildID(std::string*) override { return false; }
 
   MOCK_METHOD4(Step, bool(uint64_t, Regs*, Memory*, bool*));
   MOCK_METHOD2(GetGlobalVariable, bool(const std::string&, uint64_t*));
diff --git a/libunwindstack/tools/unwind_info.cpp b/libunwindstack/tools/unwind_info.cpp
index aebeb95..3f2dfb0 100644
--- a/libunwindstack/tools/unwind_info.cpp
+++ b/libunwindstack/tools/unwind_info.cpp
@@ -123,6 +123,15 @@
     printf("Soname: %s\n", soname.c_str());
   }
 
+  std::string build_id;
+  if (elf.GetBuildID(&build_id)) {
+    printf("Build ID: ");
+    for (size_t i = 0; i < build_id.size(); ++i) {
+      printf("%02hhx", build_id[i]);
+    }
+    printf("\n");
+  }
+
   ElfInterface* interface = elf.interface();
   if (elf.machine_type() == EM_ARM) {
     DumpArm(&elf, reinterpret_cast<ElfInterfaceArm*>(interface));
diff --git a/rootdir/Android.mk b/rootdir/Android.mk
index aad00ad..f88f6b9 100644
--- a/rootdir/Android.mk
+++ b/rootdir/Android.mk
@@ -9,6 +9,10 @@
 LOCAL_MODULE_CLASS := ETC
 LOCAL_MODULE_PATH := $(TARGET_ROOT_OUT)
 
+# The init symlink must be a post install command of a file that is to TARGET_ROOT_OUT.
+# Since init.rc is required for init and satisfies that requirement, we hijack it to create the symlink.
+LOCAL_POST_INSTALL_CMD := ln -sf /system/bin/init $(TARGET_ROOT_OUT)/init
+
 include $(BUILD_PREBUILT)
 
 #######################################
diff --git a/rootdir/ueventd.rc b/rootdir/ueventd.rc
index d47506c..d90a1ce 100644
--- a/rootdir/ueventd.rc
+++ b/rootdir/ueventd.rc
@@ -1,7 +1,5 @@
 firmware_directories /etc/firmware/ /odm/firmware/ /vendor/firmware/ /firmware/image/
-
-subsystem adf
-    devname uevent_devname
+uevent_socket_rcvbuf_size 16M
 
 subsystem graphics
     devname uevent_devpath
@@ -11,26 +9,10 @@
     devname uevent_devpath
     dirname /dev/dri
 
-subsystem oncrpc
-    devname uevent_devpath
-    dirname /dev/oncrpc
-
-subsystem adsp
-    devname uevent_devpath
-    dirname /dev/adsp
-
-subsystem msm_camera
-    devname uevent_devpath
-    dirname /dev/msm_camera
-
 subsystem input
     devname uevent_devpath
     dirname /dev/input
 
-subsystem mtd
-    devname uevent_devpath
-    dirname /dev/mtd
-
 subsystem sound
     devname uevent_devpath
     dirname /dev/snd
@@ -58,73 +40,25 @@
 
 /dev/pmsg0                0222   root       log
 
-# the msm hw3d client device node is world writable/readable.
-/dev/msm_hw3dc            0666   root       root
-
-# gpu driver for adreno200 is globally accessible
-/dev/kgsl                 0666   root       root
-
 # kms driver for drm based gpu
 /dev/dri/*                0666   root       graphics
 
 # these should not be world writable
 /dev/diag                 0660   radio      radio
-/dev/diag_arm9            0660   radio      radio
 /dev/ttyMSM0              0600   bluetooth  bluetooth
 /dev/uhid                 0660   uhid       uhid
 /dev/uinput               0660   uhid       uhid
-/dev/alarm                0664   system     radio
 /dev/rtc0                 0640   system     system
 /dev/tty0                 0660   root       system
 /dev/graphics/*           0660   root       graphics
-/dev/msm_hw3dm            0660   system     graphics
 /dev/input/*              0660   root       input
 /dev/v4l-touch*           0660   root       input
-/dev/eac                  0660   root       audio
-/dev/cam                  0660   root       camera
-/dev/pmem                 0660   system     graphics
-/dev/pmem_adsp*           0660   system     audio
-/dev/pmem_camera*         0660   system     camera
-/dev/oncrpc/*             0660   root       system
-/dev/adsp/*               0660   system     audio
 /dev/snd/*                0660   system     audio
-/dev/mt9t013              0660   system     system
-/dev/msm_camera/*         0660   system     system
-/dev/akm8976_daemon       0640   compass    system
-/dev/akm8976_aot          0640   compass    system
-/dev/akm8973_daemon       0640   compass    system
-/dev/akm8973_aot          0640   compass    system
-/dev/bma150               0640   compass    system
-/dev/cm3602               0640   compass    system
-/dev/akm8976_pffd         0640   compass    system
-/dev/lightsensor          0640   system     system
-/dev/msm_pcm_out*         0660   system     audio
-/dev/msm_pcm_in*          0660   system     audio
-/dev/msm_pcm_ctl*         0660   system     audio
-/dev/msm_snd*             0660   system     audio
 /dev/msm_mp3*             0660   system     audio
-/dev/audience_a1026*      0660   system     audio
-/dev/tpa2018d1*           0660   system     audio
-/dev/msm_audpre           0660   system     audio
-/dev/msm_audio_ctl        0660   system     audio
-/dev/htc-acoustic         0660   system     audio
-/dev/vdec                 0660   system     audio
-/dev/q6venc               0660   system     audio
-/dev/snd/dsp              0660   system     audio
-/dev/snd/dsp1             0660   system     audio
-/dev/snd/mixer            0660   system     audio
-/dev/smd0                 0640   radio      radio
-/dev/qmi                  0640   radio      radio
-/dev/qmi0                 0640   radio      radio
-/dev/qmi1                 0640   radio      radio
-/dev/qmi2                 0640   radio      radio
-/dev/bus/usb/*            0660   root       usb
-/dev/mtp_usb              0660   root       mtp
 /dev/usb_accessory        0660   root       usb
 /dev/tun                  0660   system     vpn
 
 # CDMA radio interface MUX
-/dev/ts0710mux*           0640   radio      radio
 /dev/ppp                  0660   radio      vpn
 
 # sysfs properties
@@ -134,6 +68,3 @@
 /sys/devices/virtual/usb_composite/*   enable      0664  root   system
 /sys/devices/system/cpu/cpu*   cpufreq/scaling_max_freq   0664  system system
 /sys/devices/system/cpu/cpu*   cpufreq/scaling_min_freq   0664  system system
-
-# DVB API device nodes
-/dev/dvb*                 0660   root       system
diff --git a/shell_and_utilities/README.md b/shell_and_utilities/README.md
index d8cf867..ffda3a5 100644
--- a/shell_and_utilities/README.md
+++ b/shell_and_utilities/README.md
@@ -1,5 +1,4 @@
-Android's shell and utilities
-=============================
+# Android's shell and utilities
 
 Since IceCreamSandwich Android has used
 [mksh](https://www.mirbsd.org/mksh.htm) as its shell. Before then it used
@@ -34,8 +33,7 @@
 full list for a release by running `toybox` directly.
 
 
-Android 2.3 (Gingerbread)
--------------------------
+## Android 2.3 (Gingerbread)
 
 BSD: cat dd newfs\_msdos
 
@@ -46,8 +44,7 @@
 umount uptime vmstat watchprops wipe
 
 
-Android 4.0 (IceCreamSandwich)
-------------------------------
+## Android 4.0 (IceCreamSandwich)
 
 BSD: cat dd newfs\_msdos
 
@@ -58,8 +55,7 @@
 touch umount uptime vmstat watchprops wipe
 
 
-Android 4.1-4.3 (JellyBean)
----------------------------
+## Android 4.1-4.3 (JellyBean)
 
 BSD: cat cp dd du grep newfs\_msdos
 
@@ -71,8 +67,7 @@
 sync top touch umount uptime vmstat watchprops wipe
 
 
-Android 4.4 (KitKat)
---------------------
+## Android 4.4 (KitKat)
 
 BSD: cat cp dd du grep newfs\_msdos
 
@@ -84,8 +79,7 @@
 stop swapoff swapon sync top touch umount uptime vmstat watchprops wipe
 
 
-Android 5.0 (Lollipop)
-----------------------
+## Android 5.0 (Lollipop)
 
 BSD: cat chown cp dd du grep kill ln mv printenv rm rmdir sleep sync
 
@@ -97,8 +91,7 @@
 top touch umount uptime vmstat watchprops wipe
 
 
-Android 6.0 (Marshmallow)
--------------------------
+## Android 6.0 (Marshmallow)
 
 BSD: dd du grep
 
@@ -118,8 +111,7 @@
 vmstat wc which whoami xargs yes
 
 
-Android 7.0 (Nougat)
---------------------
+## Android 7.0 (Nougat)
 
 BSD: dd grep
 
@@ -140,8 +132,7 @@
 uptime usleep vmstat wc which whoami xargs xxd yes
 
 
-Android 8.0 (Oreo)
-------------------
+## Android 8.0 (Oreo)
 
 BSD: dd grep
 
@@ -164,8 +155,8 @@
 tty ulimit umount uname uniq unix2dos uptime usleep uudecode uuencode
 vmstat wc which whoami xargs xxd yes zcat
 
-Android P
----------
+
+## Android 9.0 (Pie)
 
 BSD: dd grep
 
@@ -190,8 +181,8 @@
 umount uname uniq unix2dos uptime usleep uudecode uuencode vmstat wc
 which whoami xargs xxd yes zcat
 
-Android Q
----------
+
+## Android Q
 
 BSD: grep fsck\_msdos newfs\_msdos
 
@@ -201,17 +192,22 @@
 
 toolbox: getevent getprop
 
-toybox: acpi base64 basename blockdev cal cat chcon chgrp chmod chown
-chroot chrt cksum clear cmp comm cp cpio cut date dd df diff dirname
-dmesg dos2unix du echo env expand expr fallocate false file find flock
-fmt free getenforce groups gunzip gzip head hostname hwclock id ifconfig
-inotifyd insmod ionice iorenice kill killall ln load\_policy log logname
-losetup ls lsmod lsof lspci lsusb md5sum microcom mkdir mkfifo mknod
-mkswap mktemp modinfo modprobe more mount mountpoint mv nc netcat netstat
-nice nl nohup nsenter od paste patch pgrep pidof pkill pmap printenv
-printf ps pwd readlink realpath renice restorecon rm rmdir rmmod runcon
-sed sendevent seq setenforce setprop setsid sha1sum sha224sum sha256sum
-sha384sum sha512sum sleep sort split start stat stop strings stty swapoff
-swapon sync sysctl tac tail tar taskset tee time timeout top touch tr
-true truncate tty ulimit umount uname uniq unix2dos unshare uptime usleep
-uudecode uuencode vmstat wc which whoami xargs xxd yes zcat
+toybox: acpi base64 basename bc blkid blockdev cal cat chattr chcon chgrp
+chmod chown chroot chrt cksum clear cmp comm cp cpio cut date dd df
+diff dirname dmesg dos2unix du echo egrep env expand expr fallocate
+false fgrep file find flock fmt free freeramdisk fsfreeze getconf
+getenforce getfattr grep groups gunzip gzip head help hostname hwclock
+i2cdetect i2cdump i2cget i2cset iconv id ifconfig inotifyd insmod
+install ionice iorenice iotop kill killall ln load\_policy log logname
+losetup ls lsattr lsmod lsof lspci lsusb makedevs md5sum microcom
+mkdir mkfifo mknod mkswap mktemp modinfo modprobe more mount mountpoint
+mv nbd-client nc netcat netstat nice nl nohup nproc nsenter od partprobe
+paste patch pgrep pidof ping ping6 pivot\_root pkill pmap printenv
+printf prlimit ps pwd pwdx readlink realpath renice restorecon rev
+rfkill rm rmdir rmmod runcon sed sendevent seq setenforce setfattr
+setprop setsid sha1sum sha224sum sha256sum sha384sum sha512sum sleep
+sort split start stat stop strings stty swapoff swapon sync sysctl
+tac tail tar taskset tee time timeout top touch tr traceroute traceroute6
+true truncate tty tunctl ulimit umount uname uniq unix2dos unlink
+unshare uptime usleep uudecode uuencode uuidgen vconfig vmstat watch
+wc which whoami xargs xxd yes zcat