diff --git a/services/surfaceflinger/DisplayDevice.cpp b/services/surfaceflinger/DisplayDevice.cpp
index e16abef3d..cdc16edb9 100644
--- a/services/surfaceflinger/DisplayDevice.cpp
+++ b/services/surfaceflinger/DisplayDevice.cpp
@@ -235,8 +235,7 @@ void DisplayDevice::swapBuffers(HWComposer& hwc) const {
 
 void DisplayDevice::onSwapBuffersCompleted(HWComposer& hwc) const {
     if (hwc.initCheck() == NO_ERROR) {
-        sp<Fence> fence = hwc.getAndResetReleaseFence(mType);
-        mDisplaySurface->onFrameCommitted(fence);
+        mDisplaySurface->onFrameCommitted();
     }
 }
 
diff --git a/services/surfaceflinger/DisplayHardware/DisplaySurface.h b/services/surfaceflinger/DisplayHardware/DisplaySurface.h
index bc717a956..2eca3cbfb 100644
--- a/services/surfaceflinger/DisplayHardware/DisplaySurface.h
+++ b/services/surfaceflinger/DisplayHardware/DisplaySurface.h
@@ -49,10 +49,9 @@ public:
     virtual status_t advanceFrame() = 0;
 
     // onFrameCommitted is called after the frame has been committed to the
-    // hardware composer and a release fence is available for the buffer.
-    // Further operations on the buffer can be queued as long as they wait for
-    // the fence to signal.
-    virtual void onFrameCommitted(const sp<Fence>& fence) = 0;
+    // hardware composer. The surface collects the release fence for this
+    // frame's buffer.
+    virtual void onFrameCommitted() = 0;
 
     virtual void dump(String8& result) const = 0;
 
diff --git a/services/surfaceflinger/DisplayHardware/FramebufferSurface.cpp b/services/surfaceflinger/DisplayHardware/FramebufferSurface.cpp
index c35ac956c..1936893c8 100644
--- a/services/surfaceflinger/DisplayHardware/FramebufferSurface.cpp
+++ b/services/surfaceflinger/DisplayHardware/FramebufferSurface.cpp
@@ -140,7 +140,8 @@ void FramebufferSurface::freeBufferLocked(int slotIndex) {
     }
 }
 
-void FramebufferSurface::onFrameCommitted(const sp<Fence>& fence) {
+void FramebufferSurface::onFrameCommitted() {
+    sp<Fence> fence = mHwc.getAndResetReleaseFence(mDisplayType);
     if (fence->isValid() &&
             mCurrentBufferSlot != BufferQueue::INVALID_BUFFER_SLOT) {
         status_t err = addReleaseFence(mCurrentBufferSlot, fence);
diff --git a/services/surfaceflinger/DisplayHardware/FramebufferSurface.h b/services/surfaceflinger/DisplayHardware/FramebufferSurface.h
index 164f81f27..2fde789b4 100644
--- a/services/surfaceflinger/DisplayHardware/FramebufferSurface.h
+++ b/services/surfaceflinger/DisplayHardware/FramebufferSurface.h
@@ -43,7 +43,7 @@ public:
 
     virtual status_t compositionComplete();
     virtual status_t advanceFrame();
-    virtual void onFrameCommitted(const sp<Fence>& fence);
+    virtual void onFrameCommitted();
 
     // Implementation of DisplaySurface::dump(). Note that ConsumerBase also
     // has a non-virtual dump() with the same signature.
diff --git a/services/surfaceflinger/DisplayHardware/HWComposer.cpp b/services/surfaceflinger/DisplayHardware/HWComposer.cpp
index 9d3241093..497593bba 100644
--- a/services/surfaceflinger/DisplayHardware/HWComposer.cpp
+++ b/services/surfaceflinger/DisplayHardware/HWComposer.cpp
@@ -657,15 +657,12 @@ status_t HWComposer::commit() {
             mLists[0]->sur = eglGetCurrentSurface(EGL_DRAW);
         }
 
-        // For virtual displays, the framebufferTarget buffer also serves as
-        // the HWC output buffer, so we need to copy the buffer handle and
-        // dup() the acquire fence.
         for (size_t i=VIRTUAL_DISPLAY_ID_BASE; i<mNumDisplays; i++) {
             DisplayData& disp(mDisplayData[i]);
-            if (disp.framebufferTarget) {
-                mLists[i]->outbuf = disp.framebufferTarget->handle;
+            if (disp.outbufHandle) {
+                mLists[i]->outbuf = disp.outbufHandle;
                 mLists[i]->outbufAcquireFenceFd =
-                        dup(disp.framebufferTarget->acquireFenceFd);
+                        disp.outbufAcquireFence->dup();
             }
         }
 
@@ -706,17 +703,15 @@ status_t HWComposer::acquire(int disp) {
 
 void HWComposer::disconnectDisplay(int disp) {
     LOG_ALWAYS_FATAL_IF(disp < 0 || disp == HWC_DISPLAY_PRIMARY);
-    if (disp >= HWC_NUM_DISPLAY_TYPES) {
-        // nothing to do for these yet
-        return;
-    }
     DisplayData& dd(mDisplayData[disp]);
-    if (dd.list != NULL) {
-        free(dd.list);
-        dd.list = NULL;
-        dd.framebufferTarget = NULL;    // points into dd.list
-        dd.fbTargetHandle = NULL;
-    }
+    free(dd.list);
+    dd.list = NULL;
+    dd.framebufferTarget = NULL;    // points into dd.list
+    dd.fbTargetHandle = NULL;
+    dd.outbufHandle = NULL;
+    dd.lastRetireFence = Fence::NO_FENCE;
+    dd.lastDisplayFence = Fence::NO_FENCE;
+    dd.outbufAcquireFence = Fence::NO_FENCE;
 }
 
 int HWComposer::getVisualID() const {
@@ -765,6 +760,25 @@ void HWComposer::fbDump(String8& result) {
     }
 }
 
+status_t HWComposer::setOutputBuffer(int32_t id, const sp<Fence>& acquireFence,
+        const sp<GraphicBuffer>& buf) {
+    if (uint32_t(id)>31 || !mAllocatedDisplayIDs.hasBit(id))
+        return BAD_INDEX;
+    if (id < VIRTUAL_DISPLAY_ID_BASE)
+        return INVALID_OPERATION;
+
+    DisplayData& disp(mDisplayData[id]);
+    disp.outbufHandle = buf->handle;
+    disp.outbufAcquireFence = acquireFence;
+    return NO_ERROR;
+}
+
+sp<Fence> HWComposer::getLastRetireFence(int32_t id) {
+    if (uint32_t(id)>31 || !mAllocatedDisplayIDs.hasBit(id))
+        return Fence::NO_FENCE;
+    return mDisplayData[id].lastRetireFence;
+}
+
 /*
  * Helper template to implement a concrete HWCLayer
  * This holds the pointer to the concrete hwc layer type
@@ -1071,6 +1085,7 @@ HWComposer::DisplayData::DisplayData()
     capacity(0), list(NULL),
     framebufferTarget(NULL), fbTargetHandle(0),
     lastRetireFence(Fence::NO_FENCE), lastDisplayFence(Fence::NO_FENCE),
+    outbufHandle(NULL), outbufAcquireFence(Fence::NO_FENCE),
     events(0)
 {}
 
diff --git a/services/surfaceflinger/DisplayHardware/HWComposer.h b/services/surfaceflinger/DisplayHardware/HWComposer.h
index 346526aae..58f7e8fff 100644
--- a/services/surfaceflinger/DisplayHardware/HWComposer.h
+++ b/services/surfaceflinger/DisplayHardware/HWComposer.h
@@ -128,6 +128,17 @@ public:
     int fbCompositionComplete();
     void fbDump(String8& result);
 
+    // Set the output buffer and acquire fence for a virtual display.
+    // Returns INVALID_OPERATION if id is not a virtual display.
+    status_t setOutputBuffer(int32_t id, const sp<Fence>& acquireFence,
+            const sp<GraphicBuffer>& buf);
+
+    // Get the retire fence for the last committed frame. This fence will
+    // signal when the h/w composer is completely finished with the frame.
+    // For physical displays, it is no longer being displayed. For virtual
+    // displays, writes to the output buffer are complete.
+    sp<Fence> getLastRetireFence(int32_t id);
+
     /*
      * Interface to hardware composer's layers functionality.
      * This abstracts the HAL interface to layers which can evolve in
@@ -306,6 +317,8 @@ private:
         sp<Fence> lastRetireFence;  // signals when the last set op retires
         sp<Fence> lastDisplayFence; // signals when the last set op takes
                                     // effect on screen
+        buffer_handle_t outbufHandle;
+        sp<Fence> outbufAcquireFence;
 
         // protected by mEventControlLock
         int32_t events;
diff --git a/services/surfaceflinger/DisplayHardware/VirtualDisplaySurface.cpp b/services/surfaceflinger/DisplayHardware/VirtualDisplaySurface.cpp
index 255b77f65..b28500e8f 100644
--- a/services/surfaceflinger/DisplayHardware/VirtualDisplaySurface.cpp
+++ b/services/surfaceflinger/DisplayHardware/VirtualDisplaySurface.cpp
@@ -70,9 +70,21 @@ status_t VirtualDisplaySurface::advanceFrame() {
     return mHwc.fbPost(mDisplayId, fence, mAcquiredBuffer);
 }
 
-void VirtualDisplaySurface::onFrameCommitted(const sp<Fence>& fence) {
+void VirtualDisplaySurface::onFrameCommitted() {
     Mutex::Autolock lock(mMutex);
     if (mAcquiredBuffer != NULL) {
+        // fbFence signals when reads from the framebuffer are finished
+        // outFence signals when writes to the output buffer are finished
+        // It's unlikely that there will be an implementation where fbFence
+        // signals after outFence (in fact they'll typically be the same
+        // sync_pt), but just to be pedantic we merge them so the sink will
+        // be sure to wait until both are complete.
+        sp<Fence> fbFence = mHwc.getAndResetReleaseFence(mDisplayId);
+        sp<Fence> outFence = mHwc.getLastRetireFence(mDisplayId);
+        sp<Fence> fence = Fence::merge(
+                String8::format("HWC done: %.21s", mName.string()),
+                fbFence, outFence);
+
         status_t result = mSource->releaseBuffer(fence);
         ALOGE_IF(result != NO_ERROR, "VirtualDisplaySurface \"%s\": "
                 "failed to release buffer: %d", mName.string(), result);
diff --git a/services/surfaceflinger/DisplayHardware/VirtualDisplaySurface.h b/services/surfaceflinger/DisplayHardware/VirtualDisplaySurface.h
index 13476800f..61bafedde 100644
--- a/services/surfaceflinger/DisplayHardware/VirtualDisplaySurface.h
+++ b/services/surfaceflinger/DisplayHardware/VirtualDisplaySurface.h
@@ -58,7 +58,7 @@ public:
 
     virtual status_t compositionComplete();
     virtual status_t advanceFrame();
-    virtual void onFrameCommitted(const sp<Fence>& fence);
+    virtual void onFrameCommitted();
     virtual void dump(String8& result) const;
 
 private:
diff --git a/services/surfaceflinger/SurfaceFlinger.cpp b/services/surfaceflinger/SurfaceFlinger.cpp
index 0e5d60286..2df279ac6 100644
--- a/services/surfaceflinger/SurfaceFlinger.cpp
+++ b/services/surfaceflinger/SurfaceFlinger.cpp
@@ -2381,9 +2381,21 @@ void SurfaceFlinger::dumpAllLocked(
 }
 
 const Vector< sp<Layer> >&
-SurfaceFlinger::getLayerSortedByZForHwcDisplay(int disp) {
+SurfaceFlinger::getLayerSortedByZForHwcDisplay(int id) {
     // Note: mStateLock is held here
-    return getDisplayDevice( getBuiltInDisplay(disp) )->getVisibleLayersSortedByZ();
+    wp<IBinder> dpy;
+    for (size_t i=0 ; i<mDisplays.size() ; i++) {
+        if (mDisplays.valueAt(i)->getHwcDisplayId() == id) {
+            dpy = mDisplays.keyAt(i);
+            break;
+        }
+    }
+    if (dpy == NULL) {
+        ALOGE("getLayerSortedByZForHwcDisplay: invalid hwc display id %d", id);
+        // Just use the primary display so we have something to return
+        dpy = getBuiltInDisplay(DisplayDevice::DISPLAY_PRIMARY);
+    }
+    return getDisplayDevice(dpy)->getVisibleLayersSortedByZ();
 }
 
 bool SurfaceFlinger::startDdmConnection()
diff --git a/services/surfaceflinger/SurfaceFlinger.h b/services/surfaceflinger/SurfaceFlinger.h
index 101756024..f0e6deb1a 100644
--- a/services/surfaceflinger/SurfaceFlinger.h
+++ b/services/surfaceflinger/SurfaceFlinger.h
@@ -122,7 +122,7 @@ public:
 
     // for debugging only
     // TODO: this should be made accessible only to HWComposer
-    const Vector< sp<Layer> >& getLayerSortedByZForHwcDisplay(int disp);
+    const Vector< sp<Layer> >& getLayerSortedByZForHwcDisplay(int id);
 
 private:
     friend class Client;