diff --git a/debuggerd/tombstone.cpp b/debuggerd/tombstone.cpp
index df982a9..a7e1524 100644
--- a/debuggerd/tombstone.cpp
+++ b/debuggerd/tombstone.cpp
@@ -64,6 +64,7 @@
     case SIGFPE:
     case SIGILL:
     case SIGSEGV:
+    case SIGTRAP:
       return true;
     default:
       return false;
@@ -350,16 +351,12 @@
     return;
   }
 
-  bool is_running = (si.si_code == SI_USER);
+  bool has_fault_address = signal_has_si_addr(si.si_signo);
   uintptr_t addr = reinterpret_cast<uintptr_t>(si.si_addr);
-  addr &= ~0xfff;     // round to 4K page boundary
-  if (!is_running && addr == 0) {    // null-pointer deref
-    return;
-  }
 
-  _LOG(log, logtype::MAPS, "\nmemory map: %s\n", is_running? "" : "(fault address prefixed with --->)");
+  _LOG(log, logtype::MAPS, "\nmemory map: %s\n", has_fault_address ? "(fault address prefixed with --->)" : "");
 
-  if(!is_running && (addr < map->begin()->start)) {
+  if (has_fault_address && (addr < map->begin()->start)) {
     _LOG(log, logtype::MAPS, "--->Fault address falls at %" PRIPTR " before any mapped regions\n", addr);
   }
 
@@ -369,10 +366,10 @@
       _LOG(log, logtype::MAPS, "--->Fault address falls at %" PRIPTR " between mapped regions\n", addr);
     }
     prev = it;
-    bool in_map = !is_running && (addr >= (*it).start) && (addr < (*it).end);
+    bool in_map = has_fault_address && (addr >= (*it).start) && (addr < (*it).end);
     dump_map(log, &*it, in_map);
   }
-  if (!is_running && (addr >= (*prev).end)) {
+  if (has_fault_address && (addr >= (*prev).end)) {
     _LOG(log, logtype::MAPS, "--->Fault address falls at %" PRIPTR " after any mapped regions\n", addr);
   }
 }
diff --git a/include/system/audio.h b/include/system/audio.h
index 719a7c4..1c70240 100644
--- a/include/system/audio.h
+++ b/include/system/audio.h
@@ -110,7 +110,8 @@
     AUDIO_FLAG_AUDIBILITY_ENFORCED = 0x1,
     AUDIO_FLAG_SECURE              = 0x2,
     AUDIO_FLAG_SCO                 = 0x4,
-    AUDIO_FLAG_BEACON              = 0x8
+    AUDIO_FLAG_BEACON              = 0x8,
+    AUDIO_FLAG_HW_AV_SYNC          = 0x10
 };
 
 /* Do not change these values without updating their counterparts
@@ -696,7 +697,8 @@
     AUDIO_OUTPUT_FLAG_DEEP_BUFFER = 0x8, // use deep audio buffers
     AUDIO_OUTPUT_FLAG_COMPRESS_OFFLOAD = 0x10,  // offload playback of compressed
                                                 // streams to hardware codec
-    AUDIO_OUTPUT_FLAG_NON_BLOCKING = 0x20 // use non-blocking write
+    AUDIO_OUTPUT_FLAG_NON_BLOCKING = 0x20, // use non-blocking write
+    AUDIO_OUTPUT_FLAG_HW_AV_SYNC = 0x40 // output uses a hardware A/V synchronization source
 } audio_output_flags_t;
 
 /* The audio input flags are analogous to audio output flags.
@@ -997,6 +999,13 @@
 };
 
 
+
+/* a HW synchronization source returned by the audio HAL */
+typedef uint32_t audio_hw_sync_t;
+
+/* an invalid HW synchronization source indicating an error */
+#define AUDIO_HW_SYNC_INVALID 0
+
 static inline bool audio_is_output_device(audio_devices_t device)
 {
     if (((device & AUDIO_DEVICE_BIT_IN) == 0) &&
diff --git a/include/system/window.h b/include/system/window.h
index 60ed165..bf93b79 100644
--- a/include/system/window.h
+++ b/include/system/window.h
@@ -293,6 +293,7 @@
     NATIVE_WINDOW_SET_BUFFERS_USER_DIMENSIONS = 15, /* private */
     NATIVE_WINDOW_SET_POST_TRANSFORM_CROP   = 16,   /* private */
     NATIVE_WINDOW_SET_BUFFERS_STICKY_TRANSFORM = 17,/* private */
+    NATIVE_WINDOW_SET_SIDEBAND_STREAM       = 18,
 };
 
 /* parameter for NATIVE_WINDOW_[API_][DIS]CONNECT */
@@ -893,6 +894,17 @@
     return anw->dequeueBuffer_DEPRECATED(anw, anb);
 }
 
+/*
+ * native_window_set_sideband_stream(..., native_handle_t*)
+ * Attach a sideband buffer stream to a native window.
+ */
+static inline int native_window_set_sideband_stream(
+        struct ANativeWindow* window,
+        native_handle_t* sidebandHandle)
+{
+    return window->perform(window, NATIVE_WINDOW_SET_SIDEBAND_STREAM,
+            sidebandHandle);
+}
 
 __END_DECLS
 
diff --git a/logd/LogTimes.cpp b/logd/LogTimes.cpp
index e7e3ec2..c6dc174 100644
--- a/logd/LogTimes.cpp
+++ b/logd/LogTimes.cpp
@@ -33,7 +33,6 @@
         , mRelease(false)
         , mError(false)
         , threadRunning(false)
-        , threadTriggered(true)
         , mReader(reader)
         , mLogMask(logMask)
         , mPid(pid)
@@ -45,7 +44,9 @@
         , mStart(start)
         , mNonBlock(nonBlock)
         , mEnd(CLOCK_MONOTONIC)
-{ }
+{
+        pthread_cond_init(&threadTriggeredCondition, NULL);
+}
 
 void LogTimeEntry::startReader_Locked(void) {
     pthread_attr_t attr;
@@ -74,7 +75,6 @@
 
     lock();
 
-    me->threadRunning = false;
     if (me->mNonBlock) {
         me->error_Locked();
     }
@@ -103,6 +103,7 @@
         client->decRef();
     }
 
+    me->threadRunning = false;
     me->decRef_Locked();
 
     unlock();
@@ -119,6 +120,7 @@
     if (!client) {
         me->error();
         pthread_exit(NULL);
+        // NOTREACH
     }
 
     LogBuffer &logbuf = me->mReader.logbuf();
@@ -127,12 +129,7 @@
 
     lock();
 
-    me->threadTriggered = true;
-
-    while(me->threadTriggered && !me->isError_Locked()) {
-
-        me->threadTriggered = false;
-
+    while (me->threadRunning && !me->isError_Locked()) {
         log_time start = me->mStart;
 
         unlock();
@@ -142,24 +139,24 @@
         }
         start = logbuf.flushTo(client, start, privileged, FilterSecondPass, me);
 
+        lock();
+
         if (start == LogBufferElement::FLUSH_ERROR) {
-            me->error();
+            me->error_Locked();
         }
 
-        if (me->mNonBlock) {
-            lock();
+        if (me->mNonBlock || !me->threadRunning || me->isError_Locked()) {
             break;
         }
 
-        sched_yield();
-
-        lock();
+        pthread_cond_wait(&me->threadTriggeredCondition, &timesLock);
     }
 
     unlock();
 
     pthread_exit(NULL);
 
+    // NOTREACH
     pthread_cleanup_pop(true);
 
     return NULL;
diff --git a/logd/LogTimes.h b/logd/LogTimes.h
index beaf646..0bfa7a2 100644
--- a/logd/LogTimes.h
+++ b/logd/LogTimes.h
@@ -31,7 +31,7 @@
     bool mRelease;
     bool mError;
     bool threadRunning;
-    bool threadTriggered;
+    pthread_cond_t threadTriggeredCondition;
     pthread_t mThread;
     LogReader &mReader;
     static void *threadStart(void *me);
@@ -63,12 +63,16 @@
     bool runningReader_Locked(void) const {
         return threadRunning || mRelease || mError || mNonBlock;
     }
-    void triggerReader_Locked(void) { threadTriggered = true; }
+    void triggerReader_Locked(void) {
+        pthread_cond_signal(&threadTriggeredCondition);
+    }
+
     void triggerSkip_Locked(unsigned int skip) { skipAhead = skip; }
 
     // Called after LogTimeEntry removed from list, lock implicitly held
     void release_Locked(void) {
         mRelease = true;
+        pthread_cond_signal(&threadTriggeredCondition);
         if (mRefCount || threadRunning) {
             return;
         }
@@ -78,7 +82,7 @@
 
     // Called to mark socket in jeopardy
     void error_Locked(void) { mError = true; }
-    void error(void) { lock(); mError = true; unlock(); }
+    void error(void) { lock(); error_Locked(); unlock(); }
 
     bool isError_Locked(void) const { return mRelease || mError; }