diff --git a/include/gui/SurfaceTexture.h b/include/gui/SurfaceTexture.h
index 71d818c..a6fb12e 100644
--- a/include/gui/SurfaceTexture.h
+++ b/include/gui/SurfaceTexture.h
@@ -208,13 +208,27 @@
 
 protected:
 
-    // freeAllBuffers frees the resources (both GraphicBuffer and EGLImage) for
-    // all slots.
+    // freeBufferLocked frees the resources (both GraphicBuffer and EGLImage)
+    // for the given slot.
+    void freeBufferLocked(int index);
+
+    // freeAllBuffersLocked frees the resources (both GraphicBuffer and
+    // EGLImage) for all slots.
     void freeAllBuffersLocked();
 
+    // freeAllBuffersExceptHeadLocked frees the resources (both GraphicBuffer
+    // and EGLImage) for all slots except the head of mQueue
+    void freeAllBuffersExceptHeadLocked();
+
     // drainQueueLocked drains the buffer queue if we're in synchronous mode
-    // returns immediately otherwise.
-    void drainQueueLocked();
+    // returns immediately otherwise. return NO_INIT if SurfaceTexture
+    // became abandoned or disconnected during this call.
+    status_t drainQueueLocked();
+
+    // drainQueueAndFreeBuffersLocked drains the buffer queue if we're in
+    // synchronous mode and free all buffers. In asynchronous mode, all buffers
+    // are freed except the current buffer.
+    status_t drainQueueAndFreeBuffersLocked();
 
     static bool isExternalFormat(uint32_t format);
 
diff --git a/libs/gui/SurfaceTexture.cpp b/libs/gui/SurfaceTexture.cpp
index 631cc1c..4afca68 100644
--- a/libs/gui/SurfaceTexture.cpp
+++ b/libs/gui/SurfaceTexture.cpp
@@ -418,7 +418,9 @@
 
     if (!enabled) {
         // going to asynchronous mode, drain the queue
-        drainQueueLocked();
+        err = drainQueueLocked();
+        if (err != NO_ERROR)
+            return err;
     }
 
     if (mSynchronousMode != enabled) {
@@ -616,13 +618,9 @@
         case NATIVE_WINDOW_API_MEDIA:
         case NATIVE_WINDOW_API_CAMERA:
             if (mConnectedApi == api) {
+                drainQueueAndFreeBuffersLocked();
                 mConnectedApi = NO_CONNECTED_API;
-                if (mQueue.isEmpty()) {
-                    // if the queue is not empty, we need to wait for it
-                    // to drain before we can free all buffers. This is
-                    // done in updateTexImage().
-                    freeAllBuffersLocked();
-                }
+                mDequeueCondition.signal();
             } else {
                 LOGE("disconnect: connected to another api (cur=%d, req=%d)",
                         mConnectedApi, api);
@@ -658,7 +656,7 @@
 
     if (mAbandoned) {
         LOGE("calling updateTexImage() on an abandoned SurfaceTexture");
-        //return NO_INIT;
+        return NO_INIT;
     }
 
     // In asynchronous mode the list is guaranteed to be one buffer
@@ -667,21 +665,14 @@
         Fifo::iterator front(mQueue.begin());
         int buf = *front;
 
-        if (uint32_t(buf) >= NUM_BUFFER_SLOTS) {
-            LOGE("buffer index out of range (index=%d)", buf);
-            //return BAD_VALUE;
-        }
-
         // Update the GL texture object.
         EGLImageKHR image = mSlots[buf].mEglImage;
         if (image == EGL_NO_IMAGE_KHR) {
             EGLDisplay dpy = eglGetCurrentDisplay();
-
             if (mSlots[buf].mGraphicBuffer == 0) {
                 LOGE("buffer at slot %d is null", buf);
-                //return BAD_VALUE;
+                return BAD_VALUE;
             }
-
             image = createImage(dpy, mSlots[buf].mGraphicBuffer);
             mSlots[buf].mEglImage = image;
             mSlots[buf].mEglDisplay = dpy;
@@ -871,24 +862,64 @@
     mFrameAvailableListener = listener;
 }
 
+void SurfaceTexture::freeBufferLocked(int i) {
+    mSlots[i].mGraphicBuffer = 0;
+    mSlots[i].mBufferState = BufferSlot::FREE;
+    if (mSlots[i].mEglImage != EGL_NO_IMAGE_KHR) {
+        eglDestroyImageKHR(mSlots[i].mEglDisplay, mSlots[i].mEglImage);
+        mSlots[i].mEglImage = EGL_NO_IMAGE_KHR;
+        mSlots[i].mEglDisplay = EGL_NO_DISPLAY;
+    }
+}
+
 void SurfaceTexture::freeAllBuffersLocked() {
     LOGW_IF(!mQueue.isEmpty(),
             "freeAllBuffersLocked called but mQueue is not empty");
     for (int i = 0; i < NUM_BUFFER_SLOTS; i++) {
-        mSlots[i].mGraphicBuffer = 0;
-        mSlots[i].mBufferState = BufferSlot::FREE;
-        if (mSlots[i].mEglImage != EGL_NO_IMAGE_KHR) {
-            eglDestroyImageKHR(mSlots[i].mEglDisplay, mSlots[i].mEglImage);
-            mSlots[i].mEglImage = EGL_NO_IMAGE_KHR;
-            mSlots[i].mEglDisplay = EGL_NO_DISPLAY;
+        freeBufferLocked(i);
+    }
+}
+
+void SurfaceTexture::freeAllBuffersExceptHeadLocked() {
+    LOGW_IF(!mQueue.isEmpty(),
+            "freeAllBuffersExceptCurrentLocked called but mQueue is not empty");
+    int head = -1;
+    if (!mQueue.empty()) {
+        Fifo::iterator front(mQueue.begin());
+        head = *front;
+    }
+    for (int i = 0; i < NUM_BUFFER_SLOTS; i++) {
+        if (i != head) {
+            freeBufferLocked(i);
         }
     }
 }
 
-void SurfaceTexture::drainQueueLocked() {
+status_t SurfaceTexture::drainQueueLocked() {
     while (mSynchronousMode && !mQueue.isEmpty()) {
         mDequeueCondition.wait(mMutex);
+        if (mAbandoned) {
+            LOGE("drainQueueLocked: SurfaceTexture has been abandoned!");
+            return NO_INIT;
+        }
+        if (mConnectedApi == NO_CONNECTED_API) {
+            LOGE("drainQueueLocked: SurfaceTexture is not connected!");
+            return NO_INIT;
+        }
     }
+    return NO_ERROR;
+}
+
+status_t SurfaceTexture::drainQueueAndFreeBuffersLocked() {
+    status_t err = drainQueueLocked();
+    if (err == NO_ERROR) {
+        if (mSynchronousMode) {
+            freeAllBuffersLocked();
+        } else {
+            freeAllBuffersExceptHeadLocked();
+        }
+    }
+    return err;
 }
 
 EGLImageKHR SurfaceTexture::createImage(EGLDisplay dpy,
@@ -960,10 +991,10 @@
 
 void SurfaceTexture::abandon() {
     Mutex::Autolock lock(mMutex);
-    // clear the queue
-    freeAllBuffersLocked();
+    mQueue.clear();
     mAbandoned = true;
     mCurrentTextureBuf.clear();
+    freeAllBuffersLocked();
     mDequeueCondition.signal();
 }