Merge changes from topic "snapuserd-read-ahead"

* changes:
  libsnapshot:snapuserd:Add unit test for read-ahead code path.
  libsnapshot: Flush data to scratch space only for overlapping regions
  libsnapshot:snapuserd: read-ahead COW copy ops
  libsnapshot: Retrieve COW version from update engine manifest
  libsnapshot:snapuserd: Add 2MB scratch space in COW file
  libsnapshot:snapuserd: mmap + msync header after merge
diff --git a/bootstat/Android.bp b/bootstat/Android.bp
index 545a06f..ca59ef3 100644
--- a/bootstat/Android.bp
+++ b/bootstat/Android.bp
@@ -35,7 +35,7 @@
         "libcutils",
         "liblog",
     ],
-    static_libs: ["libgtest_prod"],
+    header_libs: ["libgtest_prod_headers"],
 }
 
 // bootstat static library
diff --git a/cpio/Android.bp b/cpio/Android.bp
index 16af079..cd2a624 100644
--- a/cpio/Android.bp
+++ b/cpio/Android.bp
@@ -8,7 +8,11 @@
     name: "mkbootfs",
     srcs: ["mkbootfs.c"],
     cflags: ["-Werror"],
-    shared_libs: ["libcutils"],
+    static_libs: [
+        "libbase",
+        "libcutils",
+        "liblog",
+    ],
     dist: {
         targets: ["dist_files"],
     },
diff --git a/debuggerd/debuggerd_test.cpp b/debuggerd/debuggerd_test.cpp
index 144faee..93725b9 100644
--- a/debuggerd/debuggerd_test.cpp
+++ b/debuggerd/debuggerd_test.cpp
@@ -274,7 +274,7 @@
   }
 
   if (signo == 0) {
-    ASSERT_TRUE(WIFEXITED(status));
+    ASSERT_TRUE(WIFEXITED(status)) << "Terminated due to unexpected signal " << WTERMSIG(status);
     ASSERT_EQ(0, WEXITSTATUS(signo));
   } else {
     ASSERT_FALSE(WIFEXITED(status));
diff --git a/debuggerd/seccomp_policy/crash_dump.arm64.policy b/debuggerd/seccomp_policy/crash_dump.arm64.policy
index 1585cc6..21887ab 100644
--- a/debuggerd/seccomp_policy/crash_dump.arm64.policy
+++ b/debuggerd/seccomp_policy/crash_dump.arm64.policy
@@ -24,7 +24,7 @@
 rt_sigprocmask: 1
 rt_sigaction: 1
 rt_tgsigqueueinfo: 1
-prctl: arg0 == PR_GET_NO_NEW_PRIVS || arg0 == 0x53564d41
+prctl: arg0 == PR_GET_NO_NEW_PRIVS || arg0 == 0x53564d41 || arg0 == PR_PAC_RESET_KEYS
 madvise: 1
 mprotect: arg2 in 0x1|0x2
 munmap: 1
diff --git a/debuggerd/seccomp_policy/crash_dump.policy.def b/debuggerd/seccomp_policy/crash_dump.policy.def
index cd5aad4..90843fc 100644
--- a/debuggerd/seccomp_policy/crash_dump.policy.def
+++ b/debuggerd/seccomp_policy/crash_dump.policy.def
@@ -34,7 +34,12 @@
 rt_tgsigqueueinfo: 1
 
 #define PR_SET_VMA 0x53564d41
+#if defined(__aarch64__)
+// PR_PAC_RESET_KEYS happens on aarch64 in pthread_create path.
+prctl: arg0 == PR_GET_NO_NEW_PRIVS || arg0 == PR_SET_VMA || arg0 == PR_PAC_RESET_KEYS
+#else
 prctl: arg0 == PR_GET_NO_NEW_PRIVS || arg0 == PR_SET_VMA
+#endif
 
 #if 0
 libminijail on vendor partitions older than P does not have constants from <sys/mman.h>.
diff --git a/fastboot/Android.bp b/fastboot/Android.bp
index ce702a0..2c70778 100644
--- a/fastboot/Android.bp
+++ b/fastboot/Android.bp
@@ -184,7 +184,6 @@
 
     static_libs: [
         "libc++fs",
-        "libgtest_prod",
         "libhealthhalutils",
         "libsnapshot_cow",
         "libsnapshot_nobinder",
@@ -193,6 +192,7 @@
 
     header_libs: [
         "avb_headers",
+        "libgtest_prod_headers",
         "libsnapshot_headers",
         "libstorage_literals_headers",
     ],
diff --git a/fs_mgr/fs_mgr_overlayfs.cpp b/fs_mgr/fs_mgr_overlayfs.cpp
index 1134f14..cb09383 100644
--- a/fs_mgr/fs_mgr_overlayfs.cpp
+++ b/fs_mgr/fs_mgr_overlayfs.cpp
@@ -116,6 +116,8 @@
 void MapScratchPartitionIfNeeded(Fstab*, const std::function<bool(const std::set<std::string>&)>&) {
 }
 
+void CleanupOldScratchFiles() {}
+
 void TeardownAllOverlayForMountPoint(const std::string&) {}
 
 }  // namespace fs_mgr
diff --git a/fs_mgr/libdm/dm_target.cpp b/fs_mgr/libdm/dm_target.cpp
index ef46eb9..b0639e6 100644
--- a/fs_mgr/libdm/dm_target.cpp
+++ b/fs_mgr/libdm/dm_target.cpp
@@ -95,7 +95,9 @@
 }
 
 void DmTargetVerity::SetVerityMode(const std::string& mode) {
-    if (mode != "restart_on_corruption" && mode != "ignore_corruption") {
+    if (mode != "panic_on_corruption" &&
+        mode != "restart_on_corruption" &&
+        mode != "ignore_corruption") {
         LOG(ERROR) << "Unknown verity mode: " << mode;
         valid_ = false;
         return;
diff --git a/fs_mgr/libfs_avb/avb_util.cpp b/fs_mgr/libfs_avb/avb_util.cpp
index 2288674..31494c1 100644
--- a/fs_mgr/libfs_avb/avb_util.cpp
+++ b/fs_mgr/libfs_avb/avb_util.cpp
@@ -61,7 +61,9 @@
 
     // Converts veritymode to the format used in kernel.
     std::string dm_verity_mode;
-    if (verity_mode == "enforcing") {
+    if (verity_mode == "panicking") {
+        dm_verity_mode = "panic_on_corruption";
+    } else if (verity_mode == "enforcing") {
         dm_verity_mode = "restart_on_corruption";
     } else if (verity_mode == "logging") {
         dm_verity_mode = "ignore_corruption";
diff --git a/fs_mgr/libsnapshot/android/snapshot/snapshot.proto b/fs_mgr/libsnapshot/android/snapshot/snapshot.proto
index 1ebc29f..92aa55c 100644
--- a/fs_mgr/libsnapshot/android/snapshot/snapshot.proto
+++ b/fs_mgr/libsnapshot/android/snapshot/snapshot.proto
@@ -139,7 +139,28 @@
     Cancelled = 7;
 };
 
-// Next: 7
+// Next 14:
+//
+// To understand the source of each failure, read snapshot.cpp. To handle new
+// sources of failure, avoid reusing an existing code; add a new code instead.
+enum MergeFailureCode {
+    Ok = 0;
+    ReadStatus = 1;
+    GetTableInfo = 2;
+    UnknownTable = 3;
+    GetTableParams = 4;
+    ActivateNewTable = 5;
+    AcquireLock = 6;
+    ListSnapshots = 7;
+    WriteStatus = 8;
+    UnknownTargetType = 9;
+    QuerySnapshotStatus = 10;
+    ExpectedMergeTarget = 11;
+    UnmergedSectorsAfterCompletion = 12;
+    UnexpectedMergeState = 13;
+};
+
+// Next: 8
 message SnapshotUpdateStatus {
     UpdateState state = 1;
 
@@ -160,9 +181,12 @@
 
     // Merge phase (if state == MERGING).
     MergePhase merge_phase = 6;
+
+    // Merge failure code, filled if state == MergeFailed.
+    MergeFailureCode merge_failure_code = 7;
 }
 
-// Next: 9
+// Next: 10
 message SnapshotMergeReport {
     // Status of the update after the merge attempts.
     UpdateState state = 1;
@@ -188,4 +212,7 @@
 
     // Time from sys.boot_completed to merge start, in milliseconds.
     uint32 boot_complete_to_merge_start_time_ms = 8;
+
+    // Merge failure code, filled if state == MergeFailed.
+    MergeFailureCode merge_failure_code = 9;
 }
diff --git a/fs_mgr/libsnapshot/include/libsnapshot/mock_snapshot.h b/fs_mgr/libsnapshot/include/libsnapshot/mock_snapshot.h
index 1cb966b..94d5055 100644
--- a/fs_mgr/libsnapshot/include/libsnapshot/mock_snapshot.h
+++ b/fs_mgr/libsnapshot/include/libsnapshot/mock_snapshot.h
@@ -27,6 +27,7 @@
     MOCK_METHOD(bool, CancelUpdate, (), (override));
     MOCK_METHOD(bool, FinishedSnapshotWrites, (bool wipe), (override));
     MOCK_METHOD(void, UpdateCowStats, (ISnapshotMergeStats * stats), (override));
+    MOCK_METHOD(MergeFailureCode, ReadMergeFailureCode, (), (override));
     MOCK_METHOD(bool, InitiateMerge, (), (override));
 
     MOCK_METHOD(UpdateState, ProcessUpdateState,
diff --git a/fs_mgr/libsnapshot/include/libsnapshot/mock_snapshot_merge_stats.h b/fs_mgr/libsnapshot/include/libsnapshot/mock_snapshot_merge_stats.h
index ac2c787..067f99c 100644
--- a/fs_mgr/libsnapshot/include/libsnapshot/mock_snapshot_merge_stats.h
+++ b/fs_mgr/libsnapshot/include/libsnapshot/mock_snapshot_merge_stats.h
@@ -34,11 +34,13 @@
     MOCK_METHOD(void, set_estimated_cow_size_bytes, (uint64_t), (override));
     MOCK_METHOD(void, set_boot_complete_time_ms, (uint32_t), (override));
     MOCK_METHOD(void, set_boot_complete_to_merge_start_time_ms, (uint32_t), (override));
+    MOCK_METHOD(void, set_merge_failure_code, (MergeFailureCode), (override));
     MOCK_METHOD(uint64_t, cow_file_size, (), (override));
     MOCK_METHOD(uint64_t, total_cow_size_bytes, (), (override));
     MOCK_METHOD(uint64_t, estimated_cow_size_bytes, (), (override));
     MOCK_METHOD(uint32_t, boot_complete_time_ms, (), (override));
     MOCK_METHOD(uint32_t, boot_complete_to_merge_start_time_ms, (), (override));
+    MOCK_METHOD(MergeFailureCode, merge_failure_code, (), (override));
     MOCK_METHOD(std::unique_ptr<Result>, Finish, (), (override));
 
     using ISnapshotMergeStats::Result;
diff --git a/fs_mgr/libsnapshot/include/libsnapshot/snapshot.h b/fs_mgr/libsnapshot/include/libsnapshot/snapshot.h
index 126e1a0..195b6f2 100644
--- a/fs_mgr/libsnapshot/include/libsnapshot/snapshot.h
+++ b/fs_mgr/libsnapshot/include/libsnapshot/snapshot.h
@@ -167,6 +167,10 @@
     virtual UpdateState ProcessUpdateState(const std::function<bool()>& callback = {},
                                            const std::function<bool()>& before_cancel = {}) = 0;
 
+    // If ProcessUpdateState() returned MergeFailed, this returns the appropriate
+    // code. Otherwise, MergeFailureCode::Ok is returned.
+    virtual MergeFailureCode ReadMergeFailureCode() = 0;
+
     // Find the status of the current update, if any.
     //
     // |progress| depends on the returned status:
@@ -332,6 +336,7 @@
     bool CancelUpdate() override;
     bool FinishedSnapshotWrites(bool wipe) override;
     void UpdateCowStats(ISnapshotMergeStats* stats) override;
+    MergeFailureCode ReadMergeFailureCode() override;
     bool InitiateMerge() override;
     UpdateState ProcessUpdateState(const std::function<bool()>& callback = {},
                                    const std::function<bool()>& before_cancel = {}) override;
@@ -381,6 +386,7 @@
     FRIEND_TEST(SnapshotTest, MapPartialSnapshot);
     FRIEND_TEST(SnapshotTest, MapSnapshot);
     FRIEND_TEST(SnapshotTest, Merge);
+    FRIEND_TEST(SnapshotTest, MergeFailureCode);
     FRIEND_TEST(SnapshotTest, NoMergeBeforeReboot);
     FRIEND_TEST(SnapshotTest, UpdateBootControlHal);
     FRIEND_TEST(SnapshotUpdateTest, DaemonTransition);
@@ -532,7 +538,8 @@
     // Interact with /metadata/ota/state.
     UpdateState ReadUpdateState(LockedFile* file);
     SnapshotUpdateStatus ReadSnapshotUpdateStatus(LockedFile* file);
-    bool WriteUpdateState(LockedFile* file, UpdateState state);
+    bool WriteUpdateState(LockedFile* file, UpdateState state,
+                          MergeFailureCode failure_code = MergeFailureCode::Ok);
     bool WriteSnapshotUpdateStatus(LockedFile* file, const SnapshotUpdateStatus& status);
     std::string GetStateFilePath() const;
 
@@ -541,12 +548,12 @@
     std::string GetMergeStateFilePath() const;
 
     // Helpers for merging.
-    bool MergeSecondPhaseSnapshots(LockedFile* lock);
-    bool SwitchSnapshotToMerge(LockedFile* lock, const std::string& name);
-    bool RewriteSnapshotDeviceTable(const std::string& dm_name);
+    MergeFailureCode MergeSecondPhaseSnapshots(LockedFile* lock);
+    MergeFailureCode SwitchSnapshotToMerge(LockedFile* lock, const std::string& name);
+    MergeFailureCode RewriteSnapshotDeviceTable(const std::string& dm_name);
     bool MarkSnapshotMergeCompleted(LockedFile* snapshot_lock, const std::string& snapshot_name);
     void AcknowledgeMergeSuccess(LockedFile* lock);
-    void AcknowledgeMergeFailure();
+    void AcknowledgeMergeFailure(MergeFailureCode failure_code);
     MergePhase DecideMergePhase(const SnapshotStatus& status);
     std::unique_ptr<LpMetadata> ReadCurrentMetadata();
 
@@ -573,14 +580,22 @@
                                  const SnapshotStatus& status);
     bool CollapseSnapshotDevice(const std::string& name, const SnapshotStatus& status);
 
+    struct MergeResult {
+        explicit MergeResult(UpdateState state,
+                             MergeFailureCode failure_code = MergeFailureCode::Ok)
+            : state(state), failure_code(failure_code) {}
+        UpdateState state;
+        MergeFailureCode failure_code;
+    };
+
     // Only the following UpdateStates are used here:
     //   UpdateState::Merging
     //   UpdateState::MergeCompleted
     //   UpdateState::MergeFailed
     //   UpdateState::MergeNeedsReboot
-    UpdateState CheckMergeState(const std::function<bool()>& before_cancel);
-    UpdateState CheckMergeState(LockedFile* lock, const std::function<bool()>& before_cancel);
-    UpdateState CheckTargetMergeState(LockedFile* lock, const std::string& name,
+    MergeResult CheckMergeState(const std::function<bool()>& before_cancel);
+    MergeResult CheckMergeState(LockedFile* lock, const std::function<bool()>& before_cancel);
+    MergeResult CheckTargetMergeState(LockedFile* lock, const std::string& name,
                                       const SnapshotUpdateStatus& update_status);
 
     // Interact with status files under /metadata/ota/snapshots.
diff --git a/fs_mgr/libsnapshot/include/libsnapshot/snapshot_stats.h b/fs_mgr/libsnapshot/include/libsnapshot/snapshot_stats.h
index e617d7a..4ce5077 100644
--- a/fs_mgr/libsnapshot/include/libsnapshot/snapshot_stats.h
+++ b/fs_mgr/libsnapshot/include/libsnapshot/snapshot_stats.h
@@ -34,11 +34,13 @@
     virtual void set_estimated_cow_size_bytes(uint64_t bytes) = 0;
     virtual void set_boot_complete_time_ms(uint32_t ms) = 0;
     virtual void set_boot_complete_to_merge_start_time_ms(uint32_t ms) = 0;
+    virtual void set_merge_failure_code(MergeFailureCode code) = 0;
     virtual uint64_t cow_file_size() = 0;
     virtual uint64_t total_cow_size_bytes() = 0;
     virtual uint64_t estimated_cow_size_bytes() = 0;
     virtual uint32_t boot_complete_time_ms() = 0;
     virtual uint32_t boot_complete_to_merge_start_time_ms() = 0;
+    virtual MergeFailureCode merge_failure_code() = 0;
 
     // Called when merge ends. Properly clean up permanent storage.
     class Result {
@@ -70,6 +72,8 @@
     uint32_t boot_complete_time_ms() override;
     void set_boot_complete_to_merge_start_time_ms(uint32_t ms) override;
     uint32_t boot_complete_to_merge_start_time_ms() override;
+    void set_merge_failure_code(MergeFailureCode code) override;
+    MergeFailureCode merge_failure_code() override;
     std::unique_ptr<Result> Finish() override;
 
   private:
diff --git a/fs_mgr/libsnapshot/include/libsnapshot/snapshot_stub.h b/fs_mgr/libsnapshot/include/libsnapshot/snapshot_stub.h
index cc75db8..a7cd939 100644
--- a/fs_mgr/libsnapshot/include/libsnapshot/snapshot_stub.h
+++ b/fs_mgr/libsnapshot/include/libsnapshot/snapshot_stub.h
@@ -29,6 +29,7 @@
     bool CancelUpdate() override;
     bool FinishedSnapshotWrites(bool wipe) override;
     void UpdateCowStats(ISnapshotMergeStats* stats) override;
+    MergeFailureCode ReadMergeFailureCode() override;
     bool InitiateMerge() override;
     UpdateState ProcessUpdateState(const std::function<bool()>& callback = {},
                                    const std::function<bool()>& before_cancel = {}) override;
diff --git a/fs_mgr/libsnapshot/inspect_cow.cpp b/fs_mgr/libsnapshot/inspect_cow.cpp
index 453b5c6..4a84fba 100644
--- a/fs_mgr/libsnapshot/inspect_cow.cpp
+++ b/fs_mgr/libsnapshot/inspect_cow.cpp
@@ -38,7 +38,8 @@
 static void usage(void) {
     LOG(ERROR) << "Usage: inspect_cow [-sd] <COW_FILE>";
     LOG(ERROR) << "\t -s Run Silent";
-    LOG(ERROR) << "\t -d Attempt to decompress\n";
+    LOG(ERROR) << "\t -d Attempt to decompress";
+    LOG(ERROR) << "\t -b Show data for failed decompress\n";
 }
 
 // Sink that always appends to the end of a string.
@@ -59,7 +60,25 @@
     std::string stream_;
 };
 
-static bool Inspect(const std::string& path, bool silent, bool decompress) {
+static void ShowBad(CowReader& reader, const struct CowOperation& op) {
+    size_t count;
+    auto buffer = std::make_unique<uint8_t[]>(op.data_length);
+
+    if (!reader.GetRawBytes(op.source, buffer.get(), op.data_length, &count)) {
+        std::cerr << "Failed to read at all!\n";
+    } else {
+        std::cout << "The Block data is:\n";
+        for (int i = 0; i < op.data_length; i++) {
+            std::cout << std::hex << (int)buffer[i];
+        }
+        std::cout << std::dec << "\n\n";
+        if (op.data_length >= sizeof(CowOperation)) {
+            std::cout << "The start, as an op, would be " << *(CowOperation*)buffer.get() << "\n";
+        }
+    }
+}
+
+static bool Inspect(const std::string& path, bool silent, bool decompress, bool show_bad) {
     android::base::unique_fd fd(open(path.c_str(), O_RDONLY));
     if (fd < 0) {
         PLOG(ERROR) << "open failed: " << path;
@@ -107,6 +126,7 @@
             if (!reader.ReadData(op, &sink)) {
                 std::cerr << "Failed to decompress for :" << op << "\n";
                 success = false;
+                if (show_bad) ShowBad(reader, op);
             }
             sink.Reset();
         }
@@ -124,7 +144,8 @@
     int ch;
     bool silent = false;
     bool decompress = false;
-    while ((ch = getopt(argc, argv, "sd")) != -1) {
+    bool show_bad = false;
+    while ((ch = getopt(argc, argv, "sdb")) != -1) {
         switch (ch) {
             case 's':
                 silent = true;
@@ -132,6 +153,9 @@
             case 'd':
                 decompress = true;
                 break;
+            case 'b':
+                show_bad = true;
+                break;
             default:
                 android::snapshot::usage();
         }
@@ -143,7 +167,7 @@
         return 1;
     }
 
-    if (!android::snapshot::Inspect(argv[optind], silent, decompress)) {
+    if (!android::snapshot::Inspect(argv[optind], silent, decompress, show_bad)) {
         return 1;
     }
     return 0;
diff --git a/fs_mgr/libsnapshot/snapshot.cpp b/fs_mgr/libsnapshot/snapshot.cpp
index 28dd3ab..8f3926a 100644
--- a/fs_mgr/libsnapshot/snapshot.cpp
+++ b/fs_mgr/libsnapshot/snapshot.cpp
@@ -746,32 +746,35 @@
         return false;
     }
 
-    bool rewrote_all = true;
+    auto reported_code = MergeFailureCode::Ok;
     for (const auto& snapshot : *merge_group) {
         // If this fails, we have no choice but to continue. Everything must
         // be merged. This is not an ideal state to be in, but it is safe,
         // because we the next boot will try again.
-        if (!SwitchSnapshotToMerge(lock.get(), snapshot)) {
+        auto code = SwitchSnapshotToMerge(lock.get(), snapshot);
+        if (code != MergeFailureCode::Ok) {
             LOG(ERROR) << "Failed to switch snapshot to a merge target: " << snapshot;
-            rewrote_all = false;
+            if (reported_code == MergeFailureCode::Ok) {
+                reported_code = code;
+            }
         }
     }
 
     // If we couldn't switch everything to a merge target, pre-emptively mark
     // this merge as failed. It will get acknowledged when WaitForMerge() is
     // called.
-    if (!rewrote_all) {
-        WriteUpdateState(lock.get(), UpdateState::MergeFailed);
+    if (reported_code != MergeFailureCode::Ok) {
+        WriteUpdateState(lock.get(), UpdateState::MergeFailed, reported_code);
     }
 
     // Return true no matter what, because a merge was initiated.
     return true;
 }
 
-bool SnapshotManager::SwitchSnapshotToMerge(LockedFile* lock, const std::string& name) {
+MergeFailureCode SnapshotManager::SwitchSnapshotToMerge(LockedFile* lock, const std::string& name) {
     SnapshotStatus status;
     if (!ReadSnapshotStatus(lock, name, &status)) {
-        return false;
+        return MergeFailureCode::ReadStatus;
     }
     if (status.state() != SnapshotState::CREATED) {
         LOG(WARNING) << "Snapshot " << name
@@ -780,8 +783,8 @@
 
     // After this, we return true because we technically did switch to a merge
     // target. Everything else we do here is just informational.
-    if (!RewriteSnapshotDeviceTable(name)) {
-        return false;
+    if (auto code = RewriteSnapshotDeviceTable(name); code != MergeFailureCode::Ok) {
+        return code;
     }
 
     status.set_state(SnapshotState::MERGING);
@@ -795,26 +798,26 @@
     if (!WriteSnapshotStatus(lock, status)) {
         LOG(ERROR) << "Could not update status file for snapshot: " << name;
     }
-    return true;
+    return MergeFailureCode::Ok;
 }
 
-bool SnapshotManager::RewriteSnapshotDeviceTable(const std::string& name) {
+MergeFailureCode SnapshotManager::RewriteSnapshotDeviceTable(const std::string& name) {
     auto& dm = DeviceMapper::Instance();
 
     std::vector<DeviceMapper::TargetInfo> old_targets;
     if (!dm.GetTableInfo(name, &old_targets)) {
         LOG(ERROR) << "Could not read snapshot device table: " << name;
-        return false;
+        return MergeFailureCode::GetTableInfo;
     }
     if (old_targets.size() != 1 || DeviceMapper::GetTargetType(old_targets[0].spec) != "snapshot") {
         LOG(ERROR) << "Unexpected device-mapper table for snapshot: " << name;
-        return false;
+        return MergeFailureCode::UnknownTable;
     }
 
     std::string base_device, cow_device;
     if (!DmTargetSnapshot::GetDevicesFromParams(old_targets[0].data, &base_device, &cow_device)) {
         LOG(ERROR) << "Could not derive underlying devices for snapshot: " << name;
-        return false;
+        return MergeFailureCode::GetTableParams;
     }
 
     DmTable table;
@@ -822,10 +825,10 @@
                                     SnapshotStorageMode::Merge, kSnapshotChunkSize);
     if (!dm.LoadTableAndActivate(name, table)) {
         LOG(ERROR) << "Could not swap device-mapper tables on snapshot device " << name;
-        return false;
+        return MergeFailureCode::ActivateNewTable;
     }
     LOG(INFO) << "Successfully switched snapshot device to a merge target: " << name;
-    return true;
+    return MergeFailureCode::Ok;
 }
 
 enum class TableQuery {
@@ -897,20 +900,20 @@
 UpdateState SnapshotManager::ProcessUpdateState(const std::function<bool()>& callback,
                                                 const std::function<bool()>& before_cancel) {
     while (true) {
-        UpdateState state = CheckMergeState(before_cancel);
-        LOG(INFO) << "ProcessUpdateState handling state: " << state;
+        auto result = CheckMergeState(before_cancel);
+        LOG(INFO) << "ProcessUpdateState handling state: " << result.state;
 
-        if (state == UpdateState::MergeFailed) {
-            AcknowledgeMergeFailure();
+        if (result.state == UpdateState::MergeFailed) {
+            AcknowledgeMergeFailure(result.failure_code);
         }
-        if (state != UpdateState::Merging) {
+        if (result.state != UpdateState::Merging) {
             // Either there is no merge, or the merge was finished, so no need
             // to keep waiting.
-            return state;
+            return result.state;
         }
 
         if (callback && !callback()) {
-            return state;
+            return result.state;
         }
 
         // This wait is not super time sensitive, so we have a relatively
@@ -919,36 +922,36 @@
     }
 }
 
-UpdateState SnapshotManager::CheckMergeState(const std::function<bool()>& before_cancel) {
+auto SnapshotManager::CheckMergeState(const std::function<bool()>& before_cancel) -> MergeResult {
     auto lock = LockExclusive();
     if (!lock) {
-        return UpdateState::MergeFailed;
+        return MergeResult(UpdateState::MergeFailed, MergeFailureCode::AcquireLock);
     }
 
-    UpdateState state = CheckMergeState(lock.get(), before_cancel);
-    LOG(INFO) << "CheckMergeState for snapshots returned: " << state;
+    auto result = CheckMergeState(lock.get(), before_cancel);
+    LOG(INFO) << "CheckMergeState for snapshots returned: " << result.state;
 
-    if (state == UpdateState::MergeCompleted) {
+    if (result.state == UpdateState::MergeCompleted) {
         // Do this inside the same lock. Failures get acknowledged without the
         // lock, because flock() might have failed.
         AcknowledgeMergeSuccess(lock.get());
-    } else if (state == UpdateState::Cancelled) {
+    } else if (result.state == UpdateState::Cancelled) {
         if (!device_->IsRecovery() && !RemoveAllUpdateState(lock.get(), before_cancel)) {
             LOG(ERROR) << "Failed to remove all update state after acknowleding cancelled update.";
         }
     }
-    return state;
+    return result;
 }
 
-UpdateState SnapshotManager::CheckMergeState(LockedFile* lock,
-                                             const std::function<bool()>& before_cancel) {
+auto SnapshotManager::CheckMergeState(LockedFile* lock, const std::function<bool()>& before_cancel)
+        -> MergeResult {
     SnapshotUpdateStatus update_status = ReadSnapshotUpdateStatus(lock);
     switch (update_status.state()) {
         case UpdateState::None:
         case UpdateState::MergeCompleted:
             // Harmless races are allowed between two callers of WaitForMerge,
             // so in both of these cases we just propagate the state.
-            return update_status.state();
+            return MergeResult(update_status.state());
 
         case UpdateState::Merging:
         case UpdateState::MergeNeedsReboot:
@@ -963,26 +966,26 @@
             // via the merge poll below, but if we never started a merge, we
             // need to also check here.
             if (HandleCancelledUpdate(lock, before_cancel)) {
-                return UpdateState::Cancelled;
+                return MergeResult(UpdateState::Cancelled);
             }
-            return update_status.state();
+            return MergeResult(update_status.state());
 
         default:
-            return update_status.state();
+            return MergeResult(update_status.state());
     }
 
     std::vector<std::string> snapshots;
     if (!ListSnapshots(lock, &snapshots)) {
-        return UpdateState::MergeFailed;
+        return MergeResult(UpdateState::MergeFailed, MergeFailureCode::ListSnapshots);
     }
 
     auto other_suffix = device_->GetOtherSlotSuffix();
 
     bool cancelled = false;
-    bool failed = false;
     bool merging = false;
     bool needs_reboot = false;
     bool wrong_phase = false;
+    MergeFailureCode failure_code = MergeFailureCode::Ok;
     for (const auto& snapshot : snapshots) {
         if (android::base::EndsWith(snapshot, other_suffix)) {
             // This will have triggered an error message in InitiateMerge already.
@@ -990,12 +993,15 @@
             continue;
         }
 
-        UpdateState snapshot_state = CheckTargetMergeState(lock, snapshot, update_status);
-        LOG(INFO) << "CheckTargetMergeState for " << snapshot << " returned: " << snapshot_state;
+        auto result = CheckTargetMergeState(lock, snapshot, update_status);
+        LOG(INFO) << "CheckTargetMergeState for " << snapshot << " returned: " << result.state;
 
-        switch (snapshot_state) {
+        switch (result.state) {
             case UpdateState::MergeFailed:
-                failed = true;
+                // Take the first failure code in case other failures compound.
+                if (failure_code == MergeFailureCode::Ok) {
+                    failure_code = result.failure_code;
+                }
                 break;
             case UpdateState::Merging:
                 merging = true;
@@ -1013,8 +1019,10 @@
                 break;
             default:
                 LOG(ERROR) << "Unknown merge status for \"" << snapshot << "\": "
-                           << "\"" << snapshot_state << "\"";
-                failed = true;
+                           << "\"" << result.state << "\"";
+                if (failure_code == MergeFailureCode::Ok) {
+                    failure_code = MergeFailureCode::UnexpectedMergeState;
+                }
                 break;
         }
     }
@@ -1023,24 +1031,25 @@
         // Note that we handle "Merging" before we handle anything else. We
         // want to poll until *nothing* is merging if we can, so everything has
         // a chance to get marked as completed or failed.
-        return UpdateState::Merging;
+        return MergeResult(UpdateState::Merging);
     }
-    if (failed) {
+    if (failure_code != MergeFailureCode::Ok) {
         // Note: since there are many drop-out cases for failure, we acknowledge
         // it in WaitForMerge rather than here and elsewhere.
-        return UpdateState::MergeFailed;
+        return MergeResult(UpdateState::MergeFailed, failure_code);
     }
     if (wrong_phase) {
         // If we got here, no other partitions are being merged, and nothing
         // failed to merge. It's safe to move to the next merge phase.
-        if (!MergeSecondPhaseSnapshots(lock)) {
-            return UpdateState::MergeFailed;
+        auto code = MergeSecondPhaseSnapshots(lock);
+        if (code != MergeFailureCode::Ok) {
+            return MergeResult(UpdateState::MergeFailed, code);
         }
-        return UpdateState::Merging;
+        return MergeResult(UpdateState::Merging);
     }
     if (needs_reboot) {
         WriteUpdateState(lock, UpdateState::MergeNeedsReboot);
-        return UpdateState::MergeNeedsReboot;
+        return MergeResult(UpdateState::MergeNeedsReboot);
     }
     if (cancelled) {
         // This is an edge case, that we handle as correctly as we sensibly can.
@@ -1048,16 +1057,17 @@
         // removed the snapshot as a result. The exact state of the update is
         // undefined now, but this can only happen on an unlocked device where
         // partitions can be flashed without wiping userdata.
-        return UpdateState::Cancelled;
+        return MergeResult(UpdateState::Cancelled);
     }
-    return UpdateState::MergeCompleted;
+    return MergeResult(UpdateState::MergeCompleted);
 }
 
-UpdateState SnapshotManager::CheckTargetMergeState(LockedFile* lock, const std::string& name,
-                                                   const SnapshotUpdateStatus& update_status) {
+auto SnapshotManager::CheckTargetMergeState(LockedFile* lock, const std::string& name,
+                                            const SnapshotUpdateStatus& update_status)
+        -> MergeResult {
     SnapshotStatus snapshot_status;
     if (!ReadSnapshotStatus(lock, name, &snapshot_status)) {
-        return UpdateState::MergeFailed;
+        return MergeResult(UpdateState::MergeFailed, MergeFailureCode::ReadStatus);
     }
 
     std::unique_ptr<LpMetadata> current_metadata;
@@ -1070,7 +1080,7 @@
         if (!current_metadata ||
             GetMetadataPartitionState(*current_metadata, name) != MetadataPartitionState::Updated) {
             DeleteSnapshot(lock, name);
-            return UpdateState::Cancelled;
+            return MergeResult(UpdateState::Cancelled);
         }
 
         // During a check, we decided the merge was complete, but we were unable to
@@ -1081,11 +1091,11 @@
         if (snapshot_status.state() == SnapshotState::MERGE_COMPLETED) {
             // NB: It's okay if this fails now, we gave cleanup our best effort.
             OnSnapshotMergeComplete(lock, name, snapshot_status);
-            return UpdateState::MergeCompleted;
+            return MergeResult(UpdateState::MergeCompleted);
         }
 
         LOG(ERROR) << "Expected snapshot or snapshot-merge for device: " << name;
-        return UpdateState::MergeFailed;
+        return MergeResult(UpdateState::MergeFailed, MergeFailureCode::UnknownTargetType);
     }
 
     // This check is expensive so it is only enabled for debugging.
@@ -1095,29 +1105,30 @@
     std::string target_type;
     DmTargetSnapshot::Status status;
     if (!QuerySnapshotStatus(name, &target_type, &status)) {
-        return UpdateState::MergeFailed;
+        return MergeResult(UpdateState::MergeFailed, MergeFailureCode::QuerySnapshotStatus);
     }
     if (target_type == "snapshot" &&
         DecideMergePhase(snapshot_status) == MergePhase::SECOND_PHASE &&
         update_status.merge_phase() == MergePhase::FIRST_PHASE) {
         // The snapshot is not being merged because it's in the wrong phase.
-        return UpdateState::None;
+        return MergeResult(UpdateState::None);
     }
     if (target_type != "snapshot-merge") {
         // We can get here if we failed to rewrite the target type in
         // InitiateMerge(). If we failed to create the target in first-stage
         // init, boot would not succeed.
         LOG(ERROR) << "Snapshot " << name << " has incorrect target type: " << target_type;
-        return UpdateState::MergeFailed;
+        return MergeResult(UpdateState::MergeFailed, MergeFailureCode::ExpectedMergeTarget);
     }
 
     // These two values are equal when merging is complete.
     if (status.sectors_allocated != status.metadata_sectors) {
         if (snapshot_status.state() == SnapshotState::MERGE_COMPLETED) {
             LOG(ERROR) << "Snapshot " << name << " is merging after being marked merge-complete.";
-            return UpdateState::MergeFailed;
+            return MergeResult(UpdateState::MergeFailed,
+                               MergeFailureCode::UnmergedSectorsAfterCompletion);
         }
-        return UpdateState::Merging;
+        return MergeResult(UpdateState::Merging);
     }
 
     // Merging is done. First, update the status file to indicate the merge
@@ -1130,18 +1141,18 @@
     // snapshot device for this partition.
     snapshot_status.set_state(SnapshotState::MERGE_COMPLETED);
     if (!WriteSnapshotStatus(lock, snapshot_status)) {
-        return UpdateState::MergeFailed;
+        return MergeResult(UpdateState::MergeFailed, MergeFailureCode::WriteStatus);
     }
     if (!OnSnapshotMergeComplete(lock, name, snapshot_status)) {
-        return UpdateState::MergeNeedsReboot;
+        return MergeResult(UpdateState::MergeNeedsReboot);
     }
-    return UpdateState::MergeCompleted;
+    return MergeResult(UpdateState::MergeCompleted, MergeFailureCode::Ok);
 }
 
-bool SnapshotManager::MergeSecondPhaseSnapshots(LockedFile* lock) {
+MergeFailureCode SnapshotManager::MergeSecondPhaseSnapshots(LockedFile* lock) {
     std::vector<std::string> snapshots;
     if (!ListSnapshots(lock, &snapshots)) {
-        return UpdateState::MergeFailed;
+        return MergeFailureCode::ListSnapshots;
     }
 
     SnapshotUpdateStatus update_status = ReadSnapshotUpdateStatus(lock);
@@ -1150,24 +1161,27 @@
 
     update_status.set_merge_phase(MergePhase::SECOND_PHASE);
     if (!WriteSnapshotUpdateStatus(lock, update_status)) {
-        return false;
+        return MergeFailureCode::WriteStatus;
     }
 
-    bool rewrote_all = true;
+    MergeFailureCode result = MergeFailureCode::Ok;
     for (const auto& snapshot : snapshots) {
         SnapshotStatus snapshot_status;
         if (!ReadSnapshotStatus(lock, snapshot, &snapshot_status)) {
-            return UpdateState::MergeFailed;
+            return MergeFailureCode::ReadStatus;
         }
         if (DecideMergePhase(snapshot_status) != MergePhase::SECOND_PHASE) {
             continue;
         }
-        if (!SwitchSnapshotToMerge(lock, snapshot)) {
+        auto code = SwitchSnapshotToMerge(lock, snapshot);
+        if (code != MergeFailureCode::Ok) {
             LOG(ERROR) << "Failed to switch snapshot to a second-phase merge target: " << snapshot;
-            rewrote_all = false;
+            if (result == MergeFailureCode::Ok) {
+                result = code;
+            }
         }
     }
-    return rewrote_all;
+    return result;
 }
 
 std::string SnapshotManager::GetSnapshotBootIndicatorPath() {
@@ -1199,7 +1213,7 @@
     RemoveAllUpdateState(lock);
 }
 
-void SnapshotManager::AcknowledgeMergeFailure() {
+void SnapshotManager::AcknowledgeMergeFailure(MergeFailureCode failure_code) {
     // Log first, so worst case, we always have a record of why the calls below
     // were being made.
     LOG(ERROR) << "Merge could not be completed and will be marked as failed.";
@@ -1216,7 +1230,7 @@
         return;
     }
 
-    WriteUpdateState(lock.get(), UpdateState::MergeFailed);
+    WriteUpdateState(lock.get(), UpdateState::MergeFailed, failure_code);
 }
 
 bool SnapshotManager::OnSnapshotMergeComplete(LockedFile* lock, const std::string& name,
@@ -2414,10 +2428,15 @@
     return status;
 }
 
-bool SnapshotManager::WriteUpdateState(LockedFile* lock, UpdateState state) {
+bool SnapshotManager::WriteUpdateState(LockedFile* lock, UpdateState state,
+                                       MergeFailureCode failure_code) {
     SnapshotUpdateStatus status;
     status.set_state(state);
 
+    if (state == UpdateState::MergeFailed) {
+        status.set_merge_failure_code(failure_code);
+    }
+
     // If we're transitioning between two valid states (eg, we're not beginning
     // or ending an OTA), then make sure to propagate the compression bit.
     if (!(state == UpdateState::Initiated || state == UpdateState::None)) {
@@ -3691,5 +3710,16 @@
     return false;
 }
 
+MergeFailureCode SnapshotManager::ReadMergeFailureCode() {
+    auto lock = LockExclusive();
+    if (!lock) return MergeFailureCode::AcquireLock;
+
+    SnapshotUpdateStatus status = ReadSnapshotUpdateStatus(lock.get());
+    if (status.state() != UpdateState::MergeFailed) {
+        return MergeFailureCode::Ok;
+    }
+    return status.merge_failure_code();
+}
+
 }  // namespace snapshot
 }  // namespace android
diff --git a/fs_mgr/libsnapshot/snapshot_stats.cpp b/fs_mgr/libsnapshot/snapshot_stats.cpp
index 7fcfcea..4a93d65 100644
--- a/fs_mgr/libsnapshot/snapshot_stats.cpp
+++ b/fs_mgr/libsnapshot/snapshot_stats.cpp
@@ -130,6 +130,14 @@
     return report_.boot_complete_to_merge_start_time_ms();
 }
 
+void SnapshotMergeStats::set_merge_failure_code(MergeFailureCode code) {
+    report_.set_merge_failure_code(code);
+}
+
+MergeFailureCode SnapshotMergeStats::merge_failure_code() {
+    return report_.merge_failure_code();
+}
+
 class SnapshotMergeStatsResultImpl : public SnapshotMergeStats::Result {
   public:
     SnapshotMergeStatsResultImpl(const SnapshotMergeReport& report,
diff --git a/fs_mgr/libsnapshot/snapshot_stub.cpp b/fs_mgr/libsnapshot/snapshot_stub.cpp
index 43825cc..1a9eda5 100644
--- a/fs_mgr/libsnapshot/snapshot_stub.cpp
+++ b/fs_mgr/libsnapshot/snapshot_stub.cpp
@@ -135,6 +135,8 @@
     uint32_t boot_complete_time_ms() override { return 0; }
     void set_boot_complete_to_merge_start_time_ms(uint32_t) override {}
     uint32_t boot_complete_to_merge_start_time_ms() override { return 0; }
+    void set_merge_failure_code(MergeFailureCode) override {}
+    MergeFailureCode merge_failure_code() { return MergeFailureCode::Ok; }
 };
 
 ISnapshotMergeStats* SnapshotManagerStub::GetSnapshotMergeStatsInstance() {
@@ -163,4 +165,9 @@
     LOG(ERROR) << __FUNCTION__ << " should never be called.";
 }
 
+auto SnapshotManagerStub::ReadMergeFailureCode() -> MergeFailureCode {
+    LOG(ERROR) << __FUNCTION__ << " should never be called.";
+    return MergeFailureCode::Ok;
+}
+
 }  // namespace android::snapshot
diff --git a/fs_mgr/libsnapshot/snapshot_test.cpp b/fs_mgr/libsnapshot/snapshot_test.cpp
index 337d410..45db7a4 100644
--- a/fs_mgr/libsnapshot/snapshot_test.cpp
+++ b/fs_mgr/libsnapshot/snapshot_test.cpp
@@ -678,6 +678,18 @@
     ASSERT_EQ(test_device->merge_status(), MergeStatus::MERGING);
 }
 
+TEST_F(SnapshotTest, MergeFailureCode) {
+    ASSERT_TRUE(AcquireLock());
+
+    ASSERT_TRUE(sm->WriteUpdateState(lock_.get(), UpdateState::MergeFailed,
+                                     MergeFailureCode::ListSnapshots));
+    ASSERT_EQ(test_device->merge_status(), MergeStatus::MERGING);
+
+    SnapshotUpdateStatus status = sm->ReadSnapshotUpdateStatus(lock_.get());
+    ASSERT_EQ(status.state(), UpdateState::MergeFailed);
+    ASSERT_EQ(status.merge_failure_code(), MergeFailureCode::ListSnapshots);
+}
+
 enum class Request { UNKNOWN, LOCK_SHARED, LOCK_EXCLUSIVE, UNLOCK, EXIT };
 std::ostream& operator<<(std::ostream& os, Request request) {
     switch (request) {
diff --git a/fs_mgr/libsnapshot/snapuserd_client.cpp b/fs_mgr/libsnapshot/snapuserd_client.cpp
index 16d02e4..41ab344 100644
--- a/fs_mgr/libsnapshot/snapuserd_client.cpp
+++ b/fs_mgr/libsnapshot/snapuserd_client.cpp
@@ -113,7 +113,7 @@
 
 bool SnapuserdClient::Sendmsg(const std::string& msg) {
     LOG(DEBUG) << "Sendmsg: msg " << msg << " sockfd: " << sockfd_;
-    ssize_t numBytesSent = TEMP_FAILURE_RETRY(send(sockfd_, msg.data(), msg.size(), 0));
+    ssize_t numBytesSent = TEMP_FAILURE_RETRY(send(sockfd_, msg.data(), msg.size(), MSG_NOSIGNAL));
     if (numBytesSent < 0) {
         PLOG(ERROR) << "Send failed";
         return false;
diff --git a/fs_mgr/libsnapshot/snapuserd_server.cpp b/fs_mgr/libsnapshot/snapuserd_server.cpp
index d813425..ff8a259 100644
--- a/fs_mgr/libsnapshot/snapuserd_server.cpp
+++ b/fs_mgr/libsnapshot/snapuserd_server.cpp
@@ -81,7 +81,7 @@
     : snapuserd_(snapuserd), misc_name_(snapuserd_->GetMiscName()) {}
 
 bool SnapuserdServer::Sendmsg(android::base::borrowed_fd fd, const std::string& msg) {
-    ssize_t ret = TEMP_FAILURE_RETRY(send(fd.get(), msg.data(), msg.size(), 0));
+    ssize_t ret = TEMP_FAILURE_RETRY(send(fd.get(), msg.data(), msg.size(), MSG_NOSIGNAL));
     if (ret < 0) {
         PLOG(ERROR) << "Snapuserd:server: send() failed";
         return false;
diff --git a/fs_mgr/tests/fs_mgr_test.cpp b/fs_mgr/tests/fs_mgr_test.cpp
index 9adb6bd..83174ef 100644
--- a/fs_mgr/tests/fs_mgr_test.cpp
+++ b/fs_mgr/tests/fs_mgr_test.cpp
@@ -184,6 +184,36 @@
         {"androidboot.space", "sha256 5248 androidboot.nospace = nope"},
 };
 
+bool CompareFlags(FstabEntry::FsMgrFlags& lhs, FstabEntry::FsMgrFlags& rhs) {
+    // clang-format off
+    return lhs.wait == rhs.wait &&
+           lhs.check == rhs.check &&
+           lhs.crypt == rhs.crypt &&
+           lhs.nonremovable == rhs.nonremovable &&
+           lhs.vold_managed == rhs.vold_managed &&
+           lhs.recovery_only == rhs.recovery_only &&
+           lhs.verify == rhs.verify &&
+           lhs.force_crypt == rhs.force_crypt &&
+           lhs.no_emulated_sd == rhs.no_emulated_sd &&
+           lhs.no_trim == rhs.no_trim &&
+           lhs.file_encryption == rhs.file_encryption &&
+           lhs.formattable == rhs.formattable &&
+           lhs.slot_select == rhs.slot_select &&
+           lhs.force_fde_or_fbe == rhs.force_fde_or_fbe &&
+           lhs.late_mount == rhs.late_mount &&
+           lhs.no_fail == rhs.no_fail &&
+           lhs.verify_at_boot == rhs.verify_at_boot &&
+           lhs.quota == rhs.quota &&
+           lhs.avb == rhs.avb &&
+           lhs.logical == rhs.logical &&
+           lhs.checkpoint_blk == rhs.checkpoint_blk &&
+           lhs.checkpoint_fs == rhs.checkpoint_fs &&
+           lhs.first_stage_mount == rhs.first_stage_mount &&
+           lhs.slot_select_other == rhs.slot_select_other &&
+           lhs.fs_verity == rhs.fs_verity;
+    // clang-format on
+}
+
 }  // namespace
 
 TEST(fs_mgr, fs_mgr_parse_cmdline) {
@@ -291,8 +321,7 @@
     EXPECT_EQ(i, fstab.size());
 }
 
-// TODO(124837435): enable it later when it can pass TreeHugger.
-TEST(fs_mgr, DISABLED_ReadFstabFromFile_MountOptions) {
+TEST(fs_mgr, ReadFstabFromFile_MountOptions) {
     TemporaryFile tf;
     ASSERT_TRUE(tf.fd != -1);
     std::string fstab_contents = R"fs(
@@ -316,88 +345,69 @@
 
     Fstab fstab;
     EXPECT_TRUE(ReadFstabFromFile(tf.path, &fstab));
-    ASSERT_EQ(11U, fstab.size());
+    ASSERT_LE(11U, fstab.size());
 
-    EXPECT_EQ("/", fstab[0].mount_point);
-    EXPECT_EQ(static_cast<unsigned long>(MS_RDONLY), fstab[0].flags);
-    EXPECT_EQ("barrier=1", fstab[0].fs_options);
+    FstabEntry* entry = GetEntryForMountPoint(&fstab, "/");
+    ASSERT_NE(nullptr, entry);
+    EXPECT_EQ(static_cast<unsigned long>(MS_RDONLY), entry->flags);
+    EXPECT_EQ("barrier=1", entry->fs_options);
 
-    EXPECT_EQ("/metadata", fstab[1].mount_point);
-    EXPECT_EQ(static_cast<unsigned long>(MS_NOATIME | MS_NOSUID | MS_NODEV), fstab[1].flags);
-    EXPECT_EQ("discard", fstab[1].fs_options);
+    entry = GetEntryForMountPoint(&fstab, "/metadata");
+    ASSERT_NE(nullptr, entry);
+    EXPECT_EQ(static_cast<unsigned long>(MS_NOATIME | MS_NOSUID | MS_NODEV), entry->flags);
+    EXPECT_EQ("discard", entry->fs_options);
 
-    EXPECT_EQ("/data", fstab[2].mount_point);
-    EXPECT_EQ(static_cast<unsigned long>(MS_NOATIME | MS_NOSUID | MS_NODEV), fstab[2].flags);
-    EXPECT_EQ("discard,reserve_root=32768,resgid=1065,fsync_mode=nobarrier", fstab[2].fs_options);
+    entry = GetEntryForMountPoint(&fstab, "/data");
+    ASSERT_NE(nullptr, entry);
+    EXPECT_EQ(static_cast<unsigned long>(MS_NOATIME | MS_NOSUID | MS_NODEV), entry->flags);
+    EXPECT_EQ("discard,reserve_root=32768,resgid=1065,fsync_mode=nobarrier", entry->fs_options);
 
-    EXPECT_EQ("/misc", fstab[3].mount_point);
-    EXPECT_EQ(0U, fstab[3].flags);
-    EXPECT_EQ("", fstab[3].fs_options);
+    entry = GetEntryForMountPoint(&fstab, "/misc");
+    ASSERT_NE(nullptr, entry);
+    EXPECT_EQ(0U, entry->flags);
+    EXPECT_EQ("", entry->fs_options);
 
-    EXPECT_EQ("/vendor/firmware_mnt", fstab[4].mount_point);
-    EXPECT_EQ(static_cast<unsigned long>(MS_RDONLY), fstab[4].flags);
+    entry = GetEntryForMountPoint(&fstab, "/vendor/firmware_mnt");
+    ASSERT_NE(nullptr, entry);
+    EXPECT_EQ(static_cast<unsigned long>(MS_RDONLY), entry->flags);
     EXPECT_EQ(
             "shortname=lower,uid=1000,gid=1000,dmask=227,fmask=337,"
             "context=u:object_r:firmware_file:s0",
-            fstab[4].fs_options);
+            entry->fs_options);
 
-    EXPECT_EQ("auto", fstab[5].mount_point);
-    EXPECT_EQ(0U, fstab[5].flags);
-    EXPECT_EQ("", fstab[5].fs_options);
+    entry = GetEntryForMountPoint(&fstab, "auto");
+    ASSERT_NE(nullptr, entry);
+    EXPECT_EQ(0U, entry->flags);
+    EXPECT_EQ("", entry->fs_options);
 
-    EXPECT_EQ("none", fstab[6].mount_point);
-    EXPECT_EQ(0U, fstab[6].flags);
-    EXPECT_EQ("", fstab[6].fs_options);
+    entry = GetEntryForMountPoint(&fstab, "none");
+    ASSERT_NE(nullptr, entry);
+    EXPECT_EQ(0U, entry->flags);
+    EXPECT_EQ("", entry->fs_options);
 
-    EXPECT_EQ("none2", fstab[7].mount_point);
-    EXPECT_EQ(static_cast<unsigned long>(MS_NODIRATIME | MS_REMOUNT | MS_BIND), fstab[7].flags);
-    EXPECT_EQ("", fstab[7].fs_options);
+    entry = GetEntryForMountPoint(&fstab, "none2");
+    ASSERT_NE(nullptr, entry);
+    EXPECT_EQ(static_cast<unsigned long>(MS_NODIRATIME | MS_REMOUNT | MS_BIND), entry->flags);
+    EXPECT_EQ("", entry->fs_options);
 
-    EXPECT_EQ("none3", fstab[8].mount_point);
-    EXPECT_EQ(static_cast<unsigned long>(MS_UNBINDABLE | MS_PRIVATE | MS_SLAVE), fstab[8].flags);
-    EXPECT_EQ("", fstab[8].fs_options);
+    entry = GetEntryForMountPoint(&fstab, "none3");
+    ASSERT_NE(nullptr, entry);
+    EXPECT_EQ(static_cast<unsigned long>(MS_UNBINDABLE | MS_PRIVATE | MS_SLAVE), entry->flags);
+    EXPECT_EQ("", entry->fs_options);
 
-    EXPECT_EQ("none4", fstab[9].mount_point);
-    EXPECT_EQ(static_cast<unsigned long>(MS_NOEXEC | MS_SHARED | MS_REC), fstab[9].flags);
-    EXPECT_EQ("", fstab[9].fs_options);
+    entry = GetEntryForMountPoint(&fstab, "none4");
+    ASSERT_NE(nullptr, entry);
+    EXPECT_EQ(static_cast<unsigned long>(MS_NOEXEC | MS_SHARED | MS_REC), entry->flags);
+    EXPECT_EQ("", entry->fs_options);
 
-    EXPECT_EQ("none5", fstab[10].mount_point);
-    EXPECT_EQ(0U, fstab[10].flags);  // rw is the same as defaults
-    EXPECT_EQ("", fstab[10].fs_options);
+    entry = GetEntryForMountPoint(&fstab, "none5");
+    ASSERT_NE(nullptr, entry);
+    // rw is the default.
+    EXPECT_EQ(0U, entry->flags);
+    EXPECT_EQ("", entry->fs_options);
 }
 
-static bool CompareFlags(FstabEntry::FsMgrFlags& lhs, FstabEntry::FsMgrFlags& rhs) {
-    // clang-format off
-    return lhs.wait == rhs.wait &&
-           lhs.check == rhs.check &&
-           lhs.crypt == rhs.crypt &&
-           lhs.nonremovable == rhs.nonremovable &&
-           lhs.vold_managed == rhs.vold_managed &&
-           lhs.recovery_only == rhs.recovery_only &&
-           lhs.verify == rhs.verify &&
-           lhs.force_crypt == rhs.force_crypt &&
-           lhs.no_emulated_sd == rhs.no_emulated_sd &&
-           lhs.no_trim == rhs.no_trim &&
-           lhs.file_encryption == rhs.file_encryption &&
-           lhs.formattable == rhs.formattable &&
-           lhs.slot_select == rhs.slot_select &&
-           lhs.force_fde_or_fbe == rhs.force_fde_or_fbe &&
-           lhs.late_mount == rhs.late_mount &&
-           lhs.no_fail == rhs.no_fail &&
-           lhs.verify_at_boot == rhs.verify_at_boot &&
-           lhs.quota == rhs.quota &&
-           lhs.avb == rhs.avb &&
-           lhs.logical == rhs.logical &&
-           lhs.checkpoint_blk == rhs.checkpoint_blk &&
-           lhs.checkpoint_fs == rhs.checkpoint_fs &&
-           lhs.first_stage_mount == rhs.first_stage_mount &&
-           lhs.slot_select_other == rhs.slot_select_other &&
-           lhs.fs_verity == rhs.fs_verity;
-    // clang-format on
-}
-
-// TODO(124837435): enable it later when it can pass TreeHugger.
-TEST(fs_mgr, DISABLED_ReadFstabFromFile_FsMgrFlags) {
+TEST(fs_mgr, ReadFstabFromFile_FsMgrFlags) {
     TemporaryFile tf;
     ASSERT_TRUE(tf.fd != -1);
     std::string fstab_contents = R"fs(
@@ -412,10 +422,10 @@
 
     Fstab fstab;
     EXPECT_TRUE(ReadFstabFromFile(tf.path, &fstab));
-    ASSERT_EQ(6U, fstab.size());
+    ASSERT_LE(6U, fstab.size());
 
-    auto entry = fstab.begin();
-    EXPECT_EQ("none0", entry->mount_point);
+    FstabEntry* entry = GetEntryForMountPoint(&fstab, "none0");
+    ASSERT_NE(nullptr, entry);
     {
         FstabEntry::FsMgrFlags flags = {};
         flags.wait = true;
@@ -426,9 +436,9 @@
         flags.verify = true;
         EXPECT_TRUE(CompareFlags(flags, entry->fs_mgr_flags));
     }
-    entry++;
 
-    EXPECT_EQ("none1", entry->mount_point);
+    entry = GetEntryForMountPoint(&fstab, "none1");
+    ASSERT_NE(nullptr, entry);
     {
         FstabEntry::FsMgrFlags flags = {};
         flags.avb = true;
@@ -439,9 +449,9 @@
         flags.no_fail = true;
         EXPECT_TRUE(CompareFlags(flags, entry->fs_mgr_flags));
     }
-    entry++;
 
-    EXPECT_EQ("none2", entry->mount_point);
+    entry = GetEntryForMountPoint(&fstab, "none2");
+    ASSERT_NE(nullptr, entry);
     {
         FstabEntry::FsMgrFlags flags = {};
         flags.first_stage_mount = true;
@@ -451,25 +461,25 @@
         flags.slot_select_other = true;
         EXPECT_TRUE(CompareFlags(flags, entry->fs_mgr_flags));
     }
-    entry++;
 
-    EXPECT_EQ("none3", entry->mount_point);
+    entry = GetEntryForMountPoint(&fstab, "none3");
+    ASSERT_NE(nullptr, entry);
     {
         FstabEntry::FsMgrFlags flags = {};
         flags.checkpoint_blk = true;
         EXPECT_TRUE(CompareFlags(flags, entry->fs_mgr_flags));
     }
-    entry++;
 
-    EXPECT_EQ("none4", entry->mount_point);
+    entry = GetEntryForMountPoint(&fstab, "none4");
+    ASSERT_NE(nullptr, entry);
     {
         FstabEntry::FsMgrFlags flags = {};
         flags.checkpoint_fs = true;
         EXPECT_TRUE(CompareFlags(flags, entry->fs_mgr_flags));
     }
-    entry++;
 
-    EXPECT_EQ("none5", entry->mount_point);
+    entry = GetEntryForMountPoint(&fstab, "none5");
+    ASSERT_NE(nullptr, entry);
     {
         FstabEntry::FsMgrFlags flags = {};
         EXPECT_TRUE(CompareFlags(flags, entry->fs_mgr_flags));
@@ -491,7 +501,7 @@
 
     Fstab fstab;
     EXPECT_TRUE(ReadFstabFromFile(tf.path, &fstab));
-    ASSERT_EQ(3U, fstab.size());
+    ASSERT_LE(3U, fstab.size());
 
     auto entry = fstab.begin();
     EXPECT_EQ("none0", entry->mount_point);
@@ -561,7 +571,7 @@
 
     Fstab fstab;
     EXPECT_TRUE(ReadFstabFromFile(tf.path, &fstab));
-    ASSERT_EQ(1U, fstab.size());
+    ASSERT_LE(1U, fstab.size());
 
     FstabEntry::FsMgrFlags flags = {};
     flags.crypt = true;
@@ -585,7 +595,7 @@
 
     Fstab fstab;
     EXPECT_TRUE(ReadFstabFromFile(tf.path, &fstab));
-    ASSERT_EQ(4U, fstab.size());
+    ASSERT_LE(4U, fstab.size());
 
     FstabEntry::FsMgrFlags flags = {};
     flags.vold_managed = true;
@@ -626,7 +636,7 @@
 
     Fstab fstab;
     EXPECT_TRUE(ReadFstabFromFile(tf.path, &fstab));
-    ASSERT_EQ(2U, fstab.size());
+    ASSERT_LE(2U, fstab.size());
 
     FstabEntry::FsMgrFlags flags = {};
 
@@ -652,7 +662,7 @@
 
     Fstab fstab;
     EXPECT_TRUE(ReadFstabFromFile(tf.path, &fstab));
-    ASSERT_EQ(2U, fstab.size());
+    ASSERT_LE(2U, fstab.size());
 
     FstabEntry::FsMgrFlags flags = {};
 
@@ -682,7 +692,7 @@
 
     Fstab fstab;
     EXPECT_TRUE(ReadFstabFromFile(tf.path, &fstab));
-    ASSERT_EQ(6U, fstab.size());
+    ASSERT_LE(6U, fstab.size());
 
     FstabEntry::FsMgrFlags flags = {};
 
@@ -728,7 +738,7 @@
 
     Fstab fstab;
     EXPECT_TRUE(ReadFstabFromFile(tf.path, &fstab));
-    ASSERT_EQ(1U, fstab.size());
+    ASSERT_LE(1U, fstab.size());
 
     auto entry = fstab.begin();
     EXPECT_EQ("none0", entry->mount_point);
@@ -751,7 +761,7 @@
 
     Fstab fstab;
     EXPECT_TRUE(ReadFstabFromFile(tf.path, &fstab));
-    ASSERT_EQ(1U, fstab.size());
+    ASSERT_LE(1U, fstab.size());
 
     auto entry = fstab.begin();
     EXPECT_EQ("none0", entry->mount_point);
@@ -775,7 +785,7 @@
 
     Fstab fstab;
     EXPECT_TRUE(ReadFstabFromFile(tf.path, &fstab));
-    ASSERT_EQ(1U, fstab.size());
+    ASSERT_LE(1U, fstab.size());
 
     FstabEntry::FsMgrFlags flags = {};
     flags.file_encryption = true;
@@ -797,7 +807,7 @@
 
     Fstab fstab;
     EXPECT_TRUE(ReadFstabFromFile(tf.path, &fstab));
-    ASSERT_EQ(2U, fstab.size());
+    ASSERT_LE(2U, fstab.size());
 
     FstabEntry::FsMgrFlags flags = {};
 
@@ -825,7 +835,7 @@
 
     Fstab fstab;
     EXPECT_TRUE(ReadFstabFromFile(tf.path, &fstab));
-    ASSERT_EQ(4U, fstab.size());
+    ASSERT_LE(4U, fstab.size());
 
     FstabEntry::FsMgrFlags flags = {};
 
@@ -863,7 +873,7 @@
 
     Fstab fstab;
     EXPECT_TRUE(ReadFstabFromFile(tf.path, &fstab));
-    ASSERT_EQ(4U, fstab.size());
+    ASSERT_LE(4U, fstab.size());
 
     FstabEntry::FsMgrFlags flags = {};
 
@@ -901,7 +911,7 @@
 
     Fstab fstab;
     EXPECT_TRUE(ReadFstabFromFile(tf.path, &fstab));
-    ASSERT_EQ(4U, fstab.size());
+    ASSERT_LE(4U, fstab.size());
 
     FstabEntry::FsMgrFlags flags = {};
 
@@ -938,7 +948,7 @@
 
     Fstab fstab;
     EXPECT_TRUE(ReadFstabFromFile(tf.path, &fstab));
-    ASSERT_EQ(2U, fstab.size());
+    ASSERT_LE(2U, fstab.size());
 
     auto entry = fstab.begin();
     EXPECT_EQ("none0", entry->mount_point);
@@ -967,7 +977,7 @@
 
     Fstab fstab;
     EXPECT_TRUE(ReadFstabFromFile(tf.path, &fstab));
-    ASSERT_EQ(1U, fstab.size());
+    ASSERT_LE(1U, fstab.size());
 
     auto entry = fstab.begin();
     EXPECT_EQ("none0", entry->mount_point);
@@ -989,7 +999,7 @@
 
     Fstab fstab;
     EXPECT_TRUE(ReadFstabFromFile(tf.path, &fstab));
-    ASSERT_EQ(1U, fstab.size());
+    ASSERT_LE(1U, fstab.size());
 
     auto entry = fstab.begin();
     EXPECT_EQ("adiantum", entry->metadata_encryption);
@@ -1006,7 +1016,7 @@
 
     Fstab fstab;
     EXPECT_TRUE(ReadFstabFromFile(tf.path, &fstab));
-    ASSERT_EQ(1U, fstab.size());
+    ASSERT_LE(1U, fstab.size());
 
     auto entry = fstab.begin();
     EXPECT_EQ("aes-256-xts:wrappedkey_v0", entry->metadata_encryption);
@@ -1027,7 +1037,7 @@
 
     Fstab fstab;
     EXPECT_TRUE(ReadFstabFromFile(tf.path, &fstab));
-    ASSERT_EQ(1U, fstab.size());
+    ASSERT_LE(1U, fstab.size());
 
     auto entry = fstab.begin();
     EXPECT_EQ("none0", entry->mount_point);
@@ -1053,7 +1063,7 @@
 
     Fstab fstab;
     EXPECT_TRUE(ReadFstabFromFile(tf.path, &fstab));
-    ASSERT_EQ(4U, fstab.size());
+    ASSERT_LE(4U, fstab.size());
 
     auto entry = fstab.begin();
 
@@ -1114,7 +1124,7 @@
 
     Fstab fstab;
     EXPECT_TRUE(ReadFstabFromFile(tf.path, &fstab));
-    ASSERT_EQ(7U, fstab.size());
+    ASSERT_LE(7U, fstab.size());
 
     FstabEntry::FsMgrFlags flags = {};
 
diff --git a/init/first_stage_init.cpp b/init/first_stage_init.cpp
index 5cde167..84cda98 100644
--- a/init/first_stage_init.cpp
+++ b/init/first_stage_init.cpp
@@ -327,28 +327,22 @@
         LOG(INFO) << "Copied ramdisk prop to " << dest;
     }
 
-    if (ForceNormalBoot(cmdline, bootconfig)) {
-        mkdir("/first_stage_ramdisk", 0755);
-        // SwitchRoot() must be called with a mount point as the target, so we bind mount the
-        // target directory to itself here.
-        if (mount("/first_stage_ramdisk", "/first_stage_ramdisk", nullptr, MS_BIND, nullptr) != 0) {
-            LOG(FATAL) << "Could not bind mount /first_stage_ramdisk to itself";
-        }
-        SwitchRoot("/first_stage_ramdisk");
-    }
-
-    std::string force_debuggable("/force_debuggable");
+    // If "/force_debuggable" is present, the second-stage init will use a userdebug
+    // sepolicy and load adb_debug.prop to allow adb root, if the device is unlocked.
+    bool found_debuggable = false;
     std::string adb_debug_prop("/adb_debug.prop");
     std::string userdebug_sepolicy("/userdebug_plat_sepolicy.cil");
-    if (IsRecoveryMode()) {
-        // Update these file paths since we didn't switch root
-        force_debuggable.insert(0, "/first_stage_ramdisk");
+    if (access("/force_debuggable", F_OK) == 0) {
+        found_debuggable = true;
+    } else if (access("/first_stage_ramdisk/force_debuggable", F_OK) == 0) {
+        // Fallback to legacy debug resource paths.
+        // TODO(b/186485355): removes the fallback path once it is not needed.
+        found_debuggable = true;
         adb_debug_prop.insert(0, "/first_stage_ramdisk");
         userdebug_sepolicy.insert(0, "/first_stage_ramdisk");
     }
-    // If this file is present, the second-stage init will use a userdebug sepolicy
-    // and load adb_debug.prop to allow adb root, if the device is unlocked.
-    if (access(force_debuggable.c_str(), F_OK) == 0) {
+
+    if (found_debuggable) {
         std::error_code ec;  // to invoke the overloaded copy_file() that won't throw.
         if (!fs::copy_file(adb_debug_prop, kDebugRamdiskProp, ec) ||
             !fs::copy_file(userdebug_sepolicy, kDebugRamdiskSEPolicy, ec)) {
@@ -359,6 +353,16 @@
         }
     }
 
+    if (ForceNormalBoot(cmdline, bootconfig)) {
+        mkdir("/first_stage_ramdisk", 0755);
+        // SwitchRoot() must be called with a mount point as the target, so we bind mount the
+        // target directory to itself here.
+        if (mount("/first_stage_ramdisk", "/first_stage_ramdisk", nullptr, MS_BIND, nullptr) != 0) {
+            LOG(FATAL) << "Could not bind mount /first_stage_ramdisk to itself";
+        }
+        SwitchRoot("/first_stage_ramdisk");
+    }
+
     if (!DoFirstStageMount(!created_devices)) {
         LOG(FATAL) << "Failed to mount required partitions early ...";
     }
diff --git a/init/property_service.cpp b/init/property_service.cpp
index 17c36bb..fe3490d 100644
--- a/init/property_service.cpp
+++ b/init/property_service.cpp
@@ -1218,13 +1218,20 @@
     });
 }
 
+// bootconfig does not allow to populate `key=value` simultaneously with
+// `key.subkey=value` which does not work with the existing code for
+// `hardware` (e.g. we want both `ro.boot.hardware=value` and
+// `ro.boot.hardware.sku=value`) and for `qemu` (Android Stidio Emulator
+// specific).
+static bool IsAllowedBootconfigKey(const std::string_view key) {
+    return (key == "hardware"sv) || (key == "qemu"sv);
+}
+
 static void ProcessBootconfig() {
     ImportBootconfig([&](const std::string& key, const std::string& value) {
         if (StartsWith(key, ANDROIDBOOT_PREFIX)) {
             InitPropertySet("ro.boot." + key.substr(ANDROIDBOOT_PREFIX.size()), value);
-        } else if (key == "hardware") {
-            // "hardware" in bootconfig replaces "androidboot.hardware" kernel
-            // cmdline parameter
+        } else if (IsAllowedBootconfigKey(key)) {
             InitPropertySet("ro.boot." + key, value);
         }
     });
diff --git a/init/reboot.cpp b/init/reboot.cpp
index d9acee5..ab0e48e 100644
--- a/init/reboot.cpp
+++ b/init/reboot.cpp
@@ -450,10 +450,22 @@
 
 // zram is able to use backing device on top of a loopback device.
 // In order to unmount /data successfully, we have to kill the loopback device first
-#define ZRAM_DEVICE   "/dev/block/zram0"
-#define ZRAM_RESET    "/sys/block/zram0/reset"
-#define ZRAM_BACK_DEV "/sys/block/zram0/backing_dev"
+#define ZRAM_DEVICE       "/dev/block/zram0"
+#define ZRAM_RESET        "/sys/block/zram0/reset"
+#define ZRAM_BACK_DEV     "/sys/block/zram0/backing_dev"
+#define ZRAM_INITSTATE    "/sys/block/zram0/initstate"
 static Result<void> KillZramBackingDevice() {
+    std::string zram_initstate;
+    if (!android::base::ReadFileToString(ZRAM_INITSTATE, &zram_initstate)) {
+        return ErrnoError() << "Failed to read " << ZRAM_INITSTATE;
+    }
+
+    zram_initstate.erase(zram_initstate.length() - 1);
+    if (zram_initstate == "0") {
+        LOG(INFO) << "Zram has not been swapped on";
+        return {};
+    }
+
     if (access(ZRAM_BACK_DEV, F_OK) != 0 && errno == ENOENT) {
         LOG(INFO) << "No zram backing device configured";
         return {};
diff --git a/init/selinux.cpp b/init/selinux.cpp
index 35a96f9..42d3023 100644
--- a/init/selinux.cpp
+++ b/init/selinux.cpp
@@ -240,25 +240,25 @@
     }
 
     // Use precompiled sepolicy only when all corresponding hashes are equal.
-    // plat_sepolicy is always checked, while system_ext and product are checked only when they
-    // exist.
     std::vector<std::pair<std::string, std::string>> sepolicy_hashes{
             {"/system/etc/selinux/plat_sepolicy_and_mapping.sha256",
              precompiled_sepolicy + ".plat_sepolicy_and_mapping.sha256"},
+            {"/system_ext/etc/selinux/system_ext_sepolicy_and_mapping.sha256",
+             precompiled_sepolicy + ".system_ext_sepolicy_and_mapping.sha256"},
+            {"/product/etc/selinux/product_sepolicy_and_mapping.sha256",
+             precompiled_sepolicy + ".product_sepolicy_and_mapping.sha256"},
     };
 
-    if (access("/system_ext/etc/selinux/system_ext_sepolicy.cil", F_OK) == 0) {
-        sepolicy_hashes.emplace_back(
-                "/system_ext/etc/selinux/system_ext_sepolicy_and_mapping.sha256",
-                precompiled_sepolicy + ".system_ext_sepolicy_and_mapping.sha256");
-    }
-
-    if (access("/product/etc/selinux/product_sepolicy.cil", F_OK) == 0) {
-        sepolicy_hashes.emplace_back("/product/etc/selinux/product_sepolicy_and_mapping.sha256",
-                                     precompiled_sepolicy + ".product_sepolicy_and_mapping.sha256");
-    }
-
     for (const auto& [actual_id_path, precompiled_id_path] : sepolicy_hashes) {
+        // Both of them should exist or both of them shouldn't exist.
+        if (access(actual_id_path.c_str(), R_OK) != 0) {
+            if (access(precompiled_id_path.c_str(), R_OK) == 0) {
+                return Error() << precompiled_id_path << " exists but " << actual_id_path
+                               << " doesn't";
+            }
+            continue;
+        }
+
         std::string actual_id;
         if (!ReadFirstLine(actual_id_path.c_str(), &actual_id)) {
             return ErrnoError() << "Failed to read " << actual_id_path;
diff --git a/init/service.cpp b/init/service.cpp
index 836dc47..c3069f5 100644
--- a/init/service.cpp
+++ b/init/service.cpp
@@ -460,7 +460,11 @@
         scon = *result;
     }
 
-    if (!IsDefaultMountNamespaceReady() && name_ != "apexd") {
+    // APEXd is always started in the "current" namespace because it is the process to set up
+    // the current namespace.
+    const bool is_apexd = args_[0] == "/system/bin/apexd";
+
+    if (!IsDefaultMountNamespaceReady() && !is_apexd) {
         // If this service is started before APEXes and corresponding linker configuration
         // get available, mark it as pre-apexd one. Note that this marking is
         // permanent. So for example, if the service is re-launched (e.g., due
diff --git a/libcutils/Android.bp b/libcutils/Android.bp
index a99cae2..68b21c6 100644
--- a/libcutils/Android.bp
+++ b/libcutils/Android.bp
@@ -362,10 +362,10 @@
     source_stem: "bindings",
     local_include_dirs: ["include"],
     bindgen_flags: [
-        "--whitelist-function", "multiuser_get_app_id",
-        "--whitelist-function", "multiuser_get_uid",
-        "--whitelist-function", "multiuser_get_user_id",
-        "--whitelist-var", "AID_KEYSTORE",
-        "--whitelist-var", "AID_USER_OFFSET",
+        "--allowlist-function", "multiuser_get_app_id",
+        "--allowlist-function", "multiuser_get_uid",
+        "--allowlist-function", "multiuser_get_user_id",
+        "--allowlist-var", "AID_KEYSTORE",
+        "--allowlist-var", "AID_USER_OFFSET",
     ],
 }
diff --git a/libcutils/include/private/android_filesystem_config.h b/libcutils/include/private/android_filesystem_config.h
index 7489281..8f22d89 100644
--- a/libcutils/include/private/android_filesystem_config.h
+++ b/libcutils/include/private/android_filesystem_config.h
@@ -128,6 +128,8 @@
 #define AID_EXT_OBB_RW 1079       /* GID for OBB directories on external storage */
 #define AID_CONTEXT_HUB 1080      /* GID for access to the Context Hub */
 #define AID_VIRTMANAGER 1081      /* VirtManager daemon */
+#define AID_ARTD 1082             /* ART Service daemon */
+#define AID_UWB 1083              /* UWB subsystem */
 /* Changes to this file must be made in AOSP, *not* in internal branches. */
 
 #define AID_SHELL 2000 /* adb and debug shell user */
diff --git a/libprocessgroup/cgrouprc/Android.bp b/libprocessgroup/cgrouprc/Android.bp
index 0cbe0cc..7522cfe 100644
--- a/libprocessgroup/cgrouprc/Android.bp
+++ b/libprocessgroup/cgrouprc/Android.bp
@@ -28,7 +28,9 @@
     // defined below. The static library is built for tests.
     vendor_available: false,
     native_bridge_supported: true,
-    llndk_stubs: "libcgrouprc.llndk",
+    llndk: {
+        symbol_file: "libcgrouprc.map.txt",
+    },
     srcs: [
         "cgroup_controller.cpp",
         "cgroup_file.cpp",
@@ -59,12 +61,3 @@
         },
     },
 }
-
-llndk_library {
-    name: "libcgrouprc.llndk",
-    symbol_file: "libcgrouprc.map.txt",
-    native_bridge_supported: true,
-    export_include_dirs: [
-        "include",
-    ],
-}
diff --git a/libprocessgroup/sched_policy.cpp b/libprocessgroup/sched_policy.cpp
index c51ee61..1a4196a 100644
--- a/libprocessgroup/sched_policy.cpp
+++ b/libprocessgroup/sched_policy.cpp
@@ -159,10 +159,9 @@
 
     if (!controller.IsUsable()) return -1;
 
-    if (!controller.GetTaskGroup(tid, &subgroup)) {
-        LOG(ERROR) << "Failed to find cgroup for tid " << tid;
+    if (!controller.GetTaskGroup(tid, &subgroup))
         return -1;
-    }
+
     return 0;
 }
 
@@ -174,11 +173,16 @@
     std::string group;
     if (schedboost_enabled()) {
         if ((getCGroupSubsys(tid, "schedtune", group) < 0) &&
-            (getCGroupSubsys(tid, "cpu", group) < 0))
-		return -1;
+            (getCGroupSubsys(tid, "cpu", group) < 0)) {
+                LOG(ERROR) << "Failed to find cpu cgroup for tid " << tid;
+                return -1;
+        }
     }
     if (group.empty() && cpusets_enabled()) {
-        if (getCGroupSubsys(tid, "cpuset", group) < 0) return -1;
+        if (getCGroupSubsys(tid, "cpuset", group) < 0) {
+            LOG(ERROR) << "Failed to find cpuset cgroup for tid " << tid;
+            return -1;
+        }
     }
 
     // TODO: replace hardcoded directories
diff --git a/libstats/pull_rust/Android.bp b/libstats/pull_rust/Android.bp
index 354c7b3..2a89e29 100644
--- a/libstats/pull_rust/Android.bp
+++ b/libstats/pull_rust/Android.bp
@@ -25,10 +25,10 @@
     source_stem: "bindings",
     bindgen_flags: [
         "--size_t-is-usize",
-        "--whitelist-function=AStatsEventList_addStatsEvent",
-        "--whitelist-function=AStatsEvent_.*",
-        "--whitelist-function=AStatsManager_.*",
-        "--whitelist-var=AStatsManager_.*",
+        "--allowlist-function=AStatsEventList_addStatsEvent",
+        "--allowlist-function=AStatsEvent_.*",
+        "--allowlist-function=AStatsManager_.*",
+        "--allowlist-var=AStatsManager_.*",
     ],
     target: {
         android: {
diff --git a/libstats/push_compat/Android.bp b/libstats/push_compat/Android.bp
index 4b2f40e..819066e 100644
--- a/libstats/push_compat/Android.bp
+++ b/libstats/push_compat/Android.bp
@@ -55,7 +55,7 @@
     export_header_lib_headers: [
         "libstatssocket_headers",
     ],
-    static_libs: ["libgtest_prod"],
+    header_libs: ["libgtest_prod_headers"],
     apex_available: ["com.android.resolv"],
     min_sdk_version: "29",
 }
diff --git a/libsync/Android.bp b/libsync/Android.bp
index 540a246..99c88cf 100644
--- a/libsync/Android.bp
+++ b/libsync/Android.bp
@@ -42,7 +42,9 @@
     recovery_available: true,
     native_bridge_supported: true,
     defaults: ["libsync_defaults"],
-    llndk_stubs: "libsync.llndk",
+    llndk: {
+        symbol_file: "libsync.map.txt",
+    },
     stubs: {
         symbol_file: "libsync.map.txt",
         versions: [
@@ -51,12 +53,6 @@
     },
 }
 
-llndk_library {
-    name: "libsync.llndk",
-    symbol_file: "libsync.map.txt",
-    export_include_dirs: ["include"],
-}
-
 cc_test {
     name: "sync-unit-tests",
     shared_libs: ["libsync"],
diff --git a/libutils/SharedBuffer_test.cpp b/libutils/SharedBuffer_test.cpp
index 3f960d2..1d6317f 100644
--- a/libutils/SharedBuffer_test.cpp
+++ b/libutils/SharedBuffer_test.cpp
@@ -32,10 +32,25 @@
     EXPECT_DEATH(android::SharedBuffer::alloc(SIZE_MAX - sizeof(android::SharedBuffer)), "");
 }
 
-TEST(SharedBufferTest, alloc_null) {
-    // Big enough to fail, not big enough to abort.
+TEST(SharedBufferTest, alloc_max) {
     SKIP_WITH_HWASAN;  // hwasan has a 2GiB allocation limit.
-    ASSERT_EQ(nullptr, android::SharedBuffer::alloc(SIZE_MAX / 2));
+
+    android::SharedBuffer* buf =
+            android::SharedBuffer::alloc(SIZE_MAX - sizeof(android::SharedBuffer) - 1);
+    if (buf != nullptr) {
+        EXPECT_NE(nullptr, buf->data());
+        buf->release();
+    }
+}
+
+TEST(SharedBufferTest, alloc_big) {
+    SKIP_WITH_HWASAN;  // hwasan has a 2GiB allocation limit.
+
+    android::SharedBuffer* buf = android::SharedBuffer::alloc(SIZE_MAX / 2);
+    if (buf != nullptr) {
+        EXPECT_NE(nullptr, buf->data());
+        buf->release();
+    }
 }
 
 TEST(SharedBufferTest, alloc_zero_size) {
@@ -56,7 +71,13 @@
     // Big enough to fail, not big enough to abort.
     SKIP_WITH_HWASAN;  // hwasan has a 2GiB allocation limit.
     android::SharedBuffer* buf = android::SharedBuffer::alloc(10);
-    ASSERT_EQ(nullptr, buf->editResize(SIZE_MAX / 2));
+    android::SharedBuffer* buf2 = buf->editResize(SIZE_MAX / 2);
+    if (buf2 == nullptr) {
+        buf->release();
+    } else {
+        EXPECT_NE(nullptr, buf2->data());
+        buf2->release();
+    }
 }
 
 TEST(SharedBufferTest, editResize_zero_size) {
diff --git a/libvndksupport/Android.bp b/libvndksupport/Android.bp
index 11c75f7..f800bf7 100644
--- a/libvndksupport/Android.bp
+++ b/libvndksupport/Android.bp
@@ -5,7 +5,9 @@
 cc_library {
     name: "libvndksupport",
     native_bridge_supported: true,
-    llndk_stubs: "libvndksupport.llndk",
+    llndk: {
+        symbol_file: "libvndksupport.map.txt",
+    },
     srcs: ["linker.cpp"],
     cflags: [
         "-Wall",
@@ -23,10 +25,3 @@
         versions: ["29"],
     },
 }
-
-llndk_library {
-    name: "libvndksupport.llndk",
-    native_bridge_supported: true,
-    symbol_file: "libvndksupport.map.txt",
-    export_include_dirs: ["include"],
-}
diff --git a/qemu_pipe/Android.bp b/qemu_pipe/Android.bp
deleted file mode 100644
index 42a69db..0000000
--- a/qemu_pipe/Android.bp
+++ /dev/null
@@ -1,24 +0,0 @@
-// Copyright 2011 The Android Open Source Project
-
-package {
-    default_applicable_licenses: ["Android-Apache-2.0"],
-}
-
-cc_library_static {
-    name: "libqemu_pipe",
-    vendor_available: true,
-    recovery_available: true,
-    apex_available: [
-        "com.android.adbd",
-        // TODO(b/151398197) remove the below
-        "//apex_available:platform",
-    ],
-    sanitize: {
-        misc_undefined: ["integer"],
-    },
-    srcs: ["qemu_pipe.cpp"],
-    local_include_dirs: ["include"],
-    static_libs: ["libbase"],
-    export_include_dirs: ["include"],
-    cflags: ["-Werror"],
-}
diff --git a/qemu_pipe/OWNERS b/qemu_pipe/OWNERS
deleted file mode 100644
index d67a329..0000000
--- a/qemu_pipe/OWNERS
+++ /dev/null
@@ -1,3 +0,0 @@
-bohu@google.com
-lfy@google.com
-rkir@google.com
diff --git a/qemu_pipe/include/qemu_pipe.h b/qemu_pipe/include/qemu_pipe.h
deleted file mode 100644
index 0987498..0000000
--- a/qemu_pipe/include/qemu_pipe.h
+++ /dev/null
@@ -1,64 +0,0 @@
-/*
- * Copyright (C) 2011 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.
- */
-#ifndef ANDROID_CORE_INCLUDE_QEMU_PIPE_H
-#define ANDROID_CORE_INCLUDE_QEMU_PIPE_H
-
-#include <stddef.h>
-
-#ifdef __cplusplus
-extern "C" {
-#endif
-// Try to open a new Qemu fast-pipe. This function returns a file descriptor
-// that can be used to communicate with a named service managed by the
-// emulator.
-//
-// This file descriptor can be used as a standard pipe/socket descriptor.
-//
-// 'pipeName' is the name of the emulator service you want to connect to,
-// and should begin with 'pipe:' (e.g. 'pipe:camera' or 'pipe:opengles').
-// For backward compatibility, the 'pipe:' prefix can be omitted, and in
-// that case, qemu_pipe_open will add it for you.
-
-// On success, return a valid file descriptor, or -1/errno on failure. E.g.:
-//
-// EINVAL  -> unknown/unsupported pipeName
-// ENOSYS  -> fast pipes not available in this system.
-//
-// ENOSYS should never happen, except if you're trying to run within a
-// misconfigured emulator.
-//
-// You should be able to open several pipes to the same pipe service,
-// except for a few special cases (e.g. GSM modem), where EBUSY will be
-// returned if more than one client tries to connect to it.
-int qemu_pipe_open(const char* pipeName);
-
-// Send a framed message |buff| of |len| bytes through the |fd| descriptor.
-// This really adds a 4-hexchar prefix describing the payload size.
-// Returns 0 on success, and -1 on error.
-int qemu_pipe_frame_send(int fd, const void* buff, size_t len);
-
-// Read a frame message from |fd|, and store it into |buff| of |len| bytes.
-// If the framed message is larger than |len|, then this returns -1 and the
-// content is lost. Otherwise, this returns the size of the message. NOTE:
-// empty messages are possible in a framed wire protocol and do not mean
-// end-of-stream.
-int qemu_pipe_frame_recv(int fd, void* buff, size_t len);
-
-#ifdef __cplusplus
-}
-#endif
-
-#endif /* ANDROID_CORE_INCLUDE_QEMU_PIPE_H */
diff --git a/qemu_pipe/qemu_pipe.cpp b/qemu_pipe/qemu_pipe.cpp
deleted file mode 100644
index 03afb21..0000000
--- a/qemu_pipe/qemu_pipe.cpp
+++ /dev/null
@@ -1,107 +0,0 @@
-/*
- * Copyright (C) 2011 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 "qemu_pipe.h"
-
-#include <unistd.h>
-#include <fcntl.h>
-#include <string.h>
-#include <errno.h>
-#include <stdio.h>
-
-#include <android-base/file.h>
-
-using android::base::ReadFully;
-using android::base::WriteFully;
-
-// Define QEMU_PIPE_DEBUG if you want to print error messages when an error
-// occurs during pipe operations. The macro should simply take a printf-style
-// formatting string followed by optional arguments.
-#ifndef QEMU_PIPE_DEBUG
-#  define  QEMU_PIPE_DEBUG(...)   (void)0
-#endif
-
-int qemu_pipe_open(const char* pipeName) {
-    if (!pipeName) {
-        errno = EINVAL;
-        return -1;
-    }
-
-    int fd = TEMP_FAILURE_RETRY(open("/dev/qemu_pipe", O_RDWR));
-    if (fd < 0) {
-        QEMU_PIPE_DEBUG("%s: Could not open /dev/qemu_pipe: %s", __FUNCTION__,
-                        strerror(errno));
-        return -1;
-    }
-
-    // Write the pipe name, *including* the trailing zero which is necessary.
-    size_t pipeNameLen = strlen(pipeName);
-    if (WriteFully(fd, pipeName, pipeNameLen + 1U)) {
-        return fd;
-    }
-
-    // now, add 'pipe:' prefix and try again
-    // Note: host side will wait for the trailing '\0' to start
-    // service lookup.
-    const char pipe_prefix[] = "pipe:";
-    if (WriteFully(fd, pipe_prefix, strlen(pipe_prefix)) &&
-            WriteFully(fd, pipeName, pipeNameLen + 1U)) {
-        return fd;
-    }
-    QEMU_PIPE_DEBUG("%s: Could not write to %s pipe service: %s",
-            __FUNCTION__, pipeName, strerror(errno));
-    close(fd);
-    return -1;
-}
-
-int qemu_pipe_frame_send(int fd, const void* buff, size_t len) {
-    char header[5];
-    snprintf(header, sizeof(header), "%04zx", len);
-    if (!WriteFully(fd, header, 4)) {
-        QEMU_PIPE_DEBUG("Can't write qemud frame header: %s", strerror(errno));
-        return -1;
-    }
-    if (!WriteFully(fd, buff, len)) {
-        QEMU_PIPE_DEBUG("Can't write qemud frame payload: %s", strerror(errno));
-        return -1;
-    }
-    return 0;
-}
-
-int qemu_pipe_frame_recv(int fd, void* buff, size_t len) {
-    char header[5];
-    if (!ReadFully(fd, header, 4)) {
-        QEMU_PIPE_DEBUG("Can't read qemud frame header: %s", strerror(errno));
-        return -1;
-    }
-    header[4] = '\0';
-    size_t size;
-    if (sscanf(header, "%04zx", &size) != 1) {
-        QEMU_PIPE_DEBUG("Malformed qemud frame header: [%.*s]", 4, header);
-        return -1;
-    }
-    if (size > len) {
-        QEMU_PIPE_DEBUG("Oversized qemud frame (% bytes, expected <= %)", size,
-                        len);
-        return -1;
-    }
-    if (!ReadFully(fd, buff, size)) {
-        QEMU_PIPE_DEBUG("Could not read qemud frame payload: %s",
-                        strerror(errno));
-        return -1;
-    }
-    return size;
-}
diff --git a/rootdir/Android.mk b/rootdir/Android.mk
index 5503cc1..99d8f9a 100644
--- a/rootdir/Android.mk
+++ b/rootdir/Android.mk
@@ -56,7 +56,6 @@
 LOCAL_LICENSE_KINDS := SPDX-license-identifier-Apache-2.0
 LOCAL_LICENSE_CONDITIONS := notice
 LOCAL_MODULE_PATH := $(TARGET_ROOT_OUT)
-LOCAL_REQUIRED_MODULES := etc_classpath
 
 EXPORT_GLOBAL_ASAN_OPTIONS :=
 ifneq ($(filter address,$(SANITIZE_TARGET)),)
@@ -186,21 +185,6 @@
 endef
 
 #######################################
-# /etc/classpath
-include $(CLEAR_VARS)
-LOCAL_MODULE := etc_classpath
-LOCAL_MODULE_CLASS := ETC
-LOCAL_MODULE_PATH := $(TARGET_OUT_ETC)
-LOCAL_MODULE_STEM := classpath
-include $(BUILD_SYSTEM)/base_rules.mk
-$(LOCAL_BUILT_MODULE):
-	@echo "Generate: $@"
-	@mkdir -p $(dir $@)
-	$(hide) echo "export BOOTCLASSPATH $(PRODUCT_BOOTCLASSPATH)" > $@
-	$(hide) echo "export DEX2OATBOOTCLASSPATH $(PRODUCT_DEX2OAT_BOOTCLASSPATH)" >> $@
-	$(hide) echo "export SYSTEMSERVERCLASSPATH $(PRODUCT_SYSTEM_SERVER_CLASSPATH)" >> $@
-
-#######################################
 # sanitizer.libraries.txt
 include $(CLEAR_VARS)
 LOCAL_MODULE := sanitizer.libraries.txt
diff --git a/rootdir/etc/linker.config.json b/rootdir/etc/linker.config.json
index d9f5526..a22ef6f 100644
--- a/rootdir/etc/linker.config.json
+++ b/rootdir/etc/linker.config.json
@@ -18,6 +18,7 @@
     "libnetd_resolv.so",
     // nn
     "libneuralnetworks.so",
+    "libneuralnetworks_shim.so",
     // statsd
     "libstatspull.so",
     "libstatssocket.so",
diff --git a/rootdir/init-debug.rc b/rootdir/init-debug.rc
index cac88fd..77a80cd 100644
--- a/rootdir/init-debug.rc
+++ b/rootdir/init-debug.rc
@@ -7,9 +7,10 @@
 on property:persist.mmc.cache_size=*
     write /sys/block/mmcblk0/cache_size ${persist.mmc.cache_size}
 
-on early-init && property:ro.product.enforce_debugfs_restrictions=true
+on early-init && property:ro.product.debugfs_restrictions.enabled=true
     mount debugfs debugfs /sys/kernel/debug
     chmod 0755 /sys/kernel/debug
 
-on property:sys.boot_completed=1 && property:ro.product.enforce_debugfs_restrictions=true
+on property:sys.boot_completed=1 && property:ro.product.debugfs_restrictions.enabled=true && \
+   property:persist.dbg.keep_debugfs_mounted=""
    umount /sys/kernel/debug
diff --git a/rootdir/init.rc b/rootdir/init.rc
index 08de882..4ec5d33 100644
--- a/rootdir/init.rc
+++ b/rootdir/init.rc
@@ -685,6 +685,10 @@
     exec - system system -- /system/bin/vdc keymaster earlyBootEnded
 
     # /data/apex is now available. Start apexd to scan and activate APEXes.
+    #
+    # To handle userspace reboots as well as devices that use FDE, make sure
+    # that apexd is started cleanly here (set apexd.status="") and that it is
+    # restarted if it's already running.
     mkdir /data/apex 0755 root system encryption=None
     mkdir /data/apex/active 0755 root system
     mkdir /data/apex/backup 0700 root system
@@ -693,7 +697,8 @@
     mkdir /data/apex/sessions 0700 root system
     mkdir /data/app-staging 0751 system system encryption=DeleteIfNecessary
     mkdir /data/apex/ota_reserved 0700 root system encryption=Require
-    start apexd
+    setprop apexd.status ""
+    restart apexd
 
     # create rest of basic filesystem structure
     mkdir /data/misc/recovery 0770 system log
@@ -917,7 +922,6 @@
     # Must start before 'odsign', as odsign depends on *CLASSPATH variables
     exec_start derive_classpath
     load_exports /data/system/environ/classpath
-    rm /data/system/environ/classpath
 
     # Start the on-device signing daemon, and wait for it to finish, to ensure
     # ART artifacts are generated if needed.
@@ -1241,7 +1245,6 @@
   setprop dev.bootcomplete ""
   setprop sys.init.updatable_crashing ""
   setprop sys.init.updatable_crashing_process_name ""
-  setprop apexd.status ""
   setprop sys.user.0.ce_available ""
   setprop sys.shutdown.requested ""
   setprop service.bootanim.exit ""