diff --git a/cmds/servicemanager/service_manager.c b/cmds/servicemanager/service_manager.c
index 21fdff0..8a8e688 100644
--- a/cmds/servicemanager/service_manager.c
+++ b/cmds/servicemanager/service_manager.c
@@ -121,6 +121,11 @@
 static int svc_can_register(const uint16_t *name, size_t name_len, pid_t spid, uid_t uid)
 {
     const char *perm = "add";
+
+    if (uid >= AID_APP) {
+        return 0; /* Don't allow apps to register services */
+    }
+
     return check_mac_perms_from_lookup(spid, uid, perm, str8(name, name_len)) ? 1 : 0;
 }
 
diff --git a/data/etc/wearable_core_hardware.xml b/data/etc/wearable_core_hardware.xml
index 4ff00b5..84230da 100644
--- a/data/etc/wearable_core_hardware.xml
+++ b/data/etc/wearable_core_hardware.xml
@@ -24,6 +24,7 @@
     <feature name="android.hardware.location" />
     <!-- devices supporting compass/magnitometer sensor must include
 	 android.hardware.sensor.compass.xml -->
+    <feature name="android.hardware.sensor.gyroscope" />
     <feature name="android.hardware.sensor.accelerometer" />
     <feature name="android.hardware.bluetooth" />
     <feature name="android.hardware.touchscreen" />
diff --git a/services/surfaceflinger/Client.cpp b/services/surfaceflinger/Client.cpp
index 415bdca..e14a59b 100644
--- a/services/surfaceflinger/Client.cpp
+++ b/services/surfaceflinger/Client.cpp
@@ -43,10 +43,7 @@
 {
     const size_t count = mLayers.size();
     for (size_t i=0 ; i<count ; i++) {
-        sp<Layer> layer(mLayers.valueAt(i).promote());
-        if (layer != 0) {
-            mFlinger->removeLayer(layer);
-        }
+        mFlinger->removeLayer(mLayers.valueAt(i));
     }
 }
 
diff --git a/services/surfaceflinger/Layer.cpp b/services/surfaceflinger/Layer.cpp
index 2b89939..785df1a 100644
--- a/services/surfaceflinger/Layer.cpp
+++ b/services/surfaceflinger/Layer.cpp
@@ -1331,9 +1331,14 @@
     // If this transaction is waiting on the receipt of a frame, generate a sync
     // point and send it to the remote layer.
     if (mCurrentState.handle != nullptr) {
-        sp<Handle> handle = static_cast<Handle*>(mCurrentState.handle.get());
-        sp<Layer> handleLayer = handle->owner.promote();
-        if (handleLayer == nullptr) {
+        sp<IBinder> strongBinder = mCurrentState.handle.promote();
+        sp<Handle> handle = nullptr;
+        sp<Layer> handleLayer = nullptr;
+        if (strongBinder != nullptr) {
+            handle = static_cast<Handle*>(strongBinder.get());
+            handleLayer = handle->owner.promote();
+        }
+        if (strongBinder == nullptr || handleLayer == nullptr) {
             ALOGE("[%s] Unable to promote Layer handle", mName.string());
             // If we can't promote the layer we are intended to wait on,
             // then it is expired or otherwise invalid. Allow this transaction
diff --git a/services/surfaceflinger/Layer.h b/services/surfaceflinger/Layer.h
index c070539..6533953 100644
--- a/services/surfaceflinger/Layer.h
+++ b/services/surfaceflinger/Layer.h
@@ -128,7 +128,7 @@
 
         // If set, defers this state update until the Layer identified by handle
         // receives a frame with the given frameNumber
-        sp<IBinder> handle;
+        wp<IBinder> handle;
         uint64_t frameNumber;
 
         // the transparentRegion hint is a bit special, it's latched only
diff --git a/services/surfaceflinger/SurfaceFlinger.cpp b/services/surfaceflinger/SurfaceFlinger.cpp
index 3ec3cc2..2a67f4c 100644
--- a/services/surfaceflinger/SurfaceFlinger.cpp
+++ b/services/surfaceflinger/SurfaceFlinger.cpp
@@ -2209,8 +2209,14 @@
     return NO_ERROR;
 }
 
-status_t SurfaceFlinger::removeLayer(const sp<Layer>& layer) {
+status_t SurfaceFlinger::removeLayer(const wp<Layer>& weakLayer) {
     Mutex::Autolock _l(mStateLock);
+    sp<Layer> layer = weakLayer.promote();
+    if (layer == nullptr) {
+        // The layer has already been removed, carry on
+        return NO_ERROR;
+    }
+
     ssize_t index = mCurrentState.layersSortedByZ.remove(layer);
     if (index >= 0) {
         mLayersPendingRemoval.push(layer);
@@ -2551,14 +2557,7 @@
 {
     // called by ~LayerCleaner() when all references to the IBinder (handle)
     // are gone
-    status_t err = NO_ERROR;
-    sp<Layer> l(layer.promote());
-    if (l != NULL) {
-        err = removeLayer(l);
-        ALOGE_IF(err<0 && err != NAME_NOT_FOUND,
-                "error removing layer=%p (%s)", l.get(), strerror(-err));
-    }
-    return err;
+    return removeLayer(layer);
 }
 
 // ---------------------------------------------------------------------------
diff --git a/services/surfaceflinger/SurfaceFlinger.h b/services/surfaceflinger/SurfaceFlinger.h
index 65e0cbf..b98924b 100644
--- a/services/surfaceflinger/SurfaceFlinger.h
+++ b/services/surfaceflinger/SurfaceFlinger.h
@@ -324,7 +324,7 @@
     status_t onLayerDestroyed(const wp<Layer>& layer);
 
     // remove a layer from SurfaceFlinger immediately
-    status_t removeLayer(const sp<Layer>& layer);
+    status_t removeLayer(const wp<Layer>& layer);
 
     // add a layer to SurfaceFlinger
     status_t addClientLayer(const sp<Client>& client,
diff --git a/services/surfaceflinger/SurfaceFlinger_hwc1.cpp b/services/surfaceflinger/SurfaceFlinger_hwc1.cpp
index 3a65e85..650d6b4 100644
--- a/services/surfaceflinger/SurfaceFlinger_hwc1.cpp
+++ b/services/surfaceflinger/SurfaceFlinger_hwc1.cpp
@@ -2125,8 +2125,14 @@
     return NO_ERROR;
 }
 
-status_t SurfaceFlinger::removeLayer(const sp<Layer>& layer) {
+status_t SurfaceFlinger::removeLayer(const wp<Layer>& weakLayer) {
     Mutex::Autolock _l(mStateLock);
+    sp<Layer> layer = weakLayer.promote();
+    if (layer == nullptr) {
+        // The layer has already been removed, carry on
+        return NO_ERROR;
+    }
+
     ssize_t index = mCurrentState.layersSortedByZ.remove(layer);
     if (index >= 0) {
         mLayersPendingRemoval.push(layer);
@@ -2467,14 +2473,7 @@
 {
     // called by ~LayerCleaner() when all references to the IBinder (handle)
     // are gone
-    status_t err = NO_ERROR;
-    sp<Layer> l(layer.promote());
-    if (l != NULL) {
-        err = removeLayer(l);
-        ALOGE_IF(err<0 && err != NAME_NOT_FOUND,
-                "error removing layer=%p (%s)", l.get(), strerror(-err));
-    }
-    return err;
+    return removeLayer(layer);
 }
 
 // ---------------------------------------------------------------------------