Merge "Fix deadlock caused by wrong locking order" into udc-dev

services/core/java/com/android/server/audio/AudioService.java

@@ -3666,6 +3666,8 @@ public class AudioService extends IAudioService.Stub
      * and aliases before mute change changed and after.
      */
     private void muteAliasStreams(int streamAlias, boolean state) {
+        // Locking mSettingsLock to avoid inversion when calling doMute -> updateVolumeGroupIndex
+        synchronized (mSettingsLock) {
             synchronized (VolumeStreamState.class) {
                 List<Integer> streamsToMute = new ArrayList<>();
                 for (int stream = 0; stream < mStreamStates.length; stream++) {
@@ -3674,7 +3676,8 @@ public class AudioService extends IAudioService.Stub
                         if (!(mCameraSoundForced
                                 && (vss.getStreamType()
                                 == AudioSystem.STREAM_SYSTEM_ENFORCED))) {
-                        boolean changed = vss.mute(state, /* apply= */ false, "muteAliasStreams");
+                            boolean changed = vss.mute(state, /* apply= */ false,
+                                    "muteAliasStreams");
                             if (changed) {
                                 streamsToMute.add(stream);
                             }
@@ -3687,6 +3690,7 @@ public class AudioService extends IAudioService.Stub
                 });
             }
         }
+    }
 
     private void broadcastMuteSetting(int streamType, boolean isMuted) {
         // Stream mute changed, fire the intent.
@@ -3699,6 +3703,9 @@ public class AudioService extends IAudioService.Stub
     // Called after a delay when volume down is pressed while muted
     private void onUnmuteStream(int stream, int flags) {
         boolean wasMuted;
+        // Locking mSettingsLock to avoid inversion when calling vss.mute -> vss.doMute ->
+        // vss.updateVolumeGroupIndex
+        synchronized (mSettingsLock) {
             synchronized (VolumeStreamState.class) {
                 final VolumeStreamState streamState = mStreamStates[stream];
                 // if unmuting causes a change, it was muted
@@ -3714,6 +3721,7 @@ public class AudioService extends IAudioService.Stub
                 }
             }
         }
+    }
 
     @GuardedBy("mHdmiClientLock")
     private void maybeSendSystemAudioStatusCommand(boolean isMuteAdjust) {
@@ -7611,9 +7619,13 @@ public class AudioService extends IAudioService.Stub
                 Log.i(TAG, String.format("onAccessoryPlugMediaUnmute unmuting device=%d [%s]",
                         newDevice, AudioSystem.getOutputDeviceName(newDevice)));
             }
+            // Locking mSettingsLock to avoid inversion when calling vss.mute -> vss.doMute ->
+            // vss.updateVolumeGroupIndex
+            synchronized (mSettingsLock) {
                 mStreamStates[AudioSystem.STREAM_MUSIC].mute(false, "onAccessoryPlugMediaUnmute");
             }
         }
+    }
 
     /**
      * See AudioManager.hasHapticChannels(Context, Uri).
@@ -7646,11 +7658,16 @@ public class AudioService extends IAudioService.Stub
                 continue;
             }
         }
+
+        // need mSettingsLock for vgs.applyAllVolumes -> vss.setIndex which grabs this lock after
+        // VSS.class. Locking order needs to be preserved
+        synchronized (mSettingsLock) {
             for (int i = 0; i < sVolumeGroupStates.size(); i++) {
                 final VolumeGroupState vgs = sVolumeGroupStates.valueAt(i);
                 vgs.applyAllVolumes(/* userSwitch= */ false);
             }
         }
+    }
 
     private void ensureValidAttributes(AudioVolumeGroup avg) {
         boolean hasAtLeastOneValidAudioAttributes = avg.getAudioAttributes().stream()
@@ -7685,11 +7702,16 @@ public class AudioService extends IAudioService.Stub
         if (DEBUG_VOL) {
             Log.v(TAG, "restoreVolumeGroups");
         }
+
+        // need mSettingsLock for vgs.applyAllVolumes -> vss.setIndex which grabs this lock after
+        // VSS.class. Locking order needs to be preserved
+        synchronized (mSettingsLock) {
             for (int i = 0; i < sVolumeGroupStates.size(); i++) {
                 final VolumeGroupState vgs = sVolumeGroupStates.valueAt(i);
                 vgs.applyAllVolumes(false/*userSwitch*/);
             }
         }
+    }
 
     private void dumpVolumeGroups(PrintWriter pw) {
         pw.println("\nVolume Groups (device: index)");
@@ -7824,6 +7846,7 @@ public class AudioService extends IAudioService.Stub
         }
 
         public void adjustVolume(int direction, int flags) {
+            synchronized (mSettingsLock) {
                 synchronized (AudioService.VolumeStreamState.class) {
                     int device = getDeviceForVolume();
                     int previousIndex = getIndex(device);
@@ -7870,6 +7893,7 @@ public class AudioService extends IAudioService.Stub
                     }
                 }
             }
+        }
 
         public int getVolumeIndex() {
             synchronized (AudioService.VolumeStreamState.class) {
@@ -7878,6 +7902,7 @@ public class AudioService extends IAudioService.Stub
         }
 
         public void setVolumeIndex(int index, int flags) {
+            synchronized (mSettingsLock) {
                 synchronized (AudioService.VolumeStreamState.class) {
                     if (mUseFixedVolume) {
                         return;
@@ -7885,6 +7910,7 @@ public class AudioService extends IAudioService.Stub
                     setVolumeIndex(index, getDeviceForVolume(), flags);
                 }
             }
+        }
 
         @GuardedBy("AudioService.VolumeStreamState.class")
         private void setVolumeIndex(int index, int device, int flags) {
@@ -8689,6 +8715,10 @@ public class AudioService extends IAudioService.Stub
 
         // If associated to volume group, update group cache
         private void updateVolumeGroupIndex(int device, boolean forceMuteState) {
+            // need mSettingsLock when called from setIndex for vgs.mute -> vgs.applyAllVolumes ->
+            // vss.setIndex which grabs this lock after VSS.class. Locking order needs to be
+            // preserved
+            synchronized (mSettingsLock) {
                 synchronized (VolumeStreamState.class) {
                     if (mVolumeGroupState != null) {
                         int groupIndex = (getIndex(device) + 5) / 10;
@@ -8696,13 +8726,14 @@ public class AudioService extends IAudioService.Stub
                             Log.d(TAG, "updateVolumeGroupIndex for stream " + mStreamType
                                     + ", muted=" + mIsMuted + ", device=" + device + ", index="
                                     + getIndex(device) + ", group " + mVolumeGroupState.name()
-                                + " Muted=" + mVolumeGroupState.isMuted() + ", Index=" + groupIndex
+                                    + " Muted=" + mVolumeGroupState.isMuted() + ", Index="
-                                + ", forceMuteState=" + forceMuteState);
+                                    + groupIndex + ", forceMuteState=" + forceMuteState);
                         }
                         mVolumeGroupState.updateVolumeIndex(groupIndex, device);
                         // Only propage mute of stream when applicable
                         if (isMutable()) {
-                        // For call stream, align mute only when muted, not when index is set to 0
+                            // For call stream, align mute only when muted, not when index is set to
+                            // 0
                             mVolumeGroupState.mute(
                                     forceMuteState ? mIsMuted :
                                             (groupIndex == 0 && !isCallStream(mStreamType))
@@ -8711,6 +8742,7 @@ public class AudioService extends IAudioService.Stub
                     }
                 }
             }
+        }
 
         /**
          * Mute/unmute the stream