diff --git a/modules/gralloc/gralloc.cpp b/modules/gralloc/gralloc.cpp
index a01a95c..8c496dc 100644
--- a/modules/gralloc/gralloc.cpp
+++ b/modules/gralloc/gralloc.cpp
@@ -389,38 +389,36 @@
         return -EINVAL;
 
     private_handle_t const* hnd = reinterpret_cast<private_handle_t const*>(handle);
-    if (hnd->flags & private_handle_t::PRIV_FLAGS_FRAMEBUFFER) 
-    {
+    if (hnd->flags & private_handle_t::PRIV_FLAGS_FRAMEBUFFER) {
         // free this buffer
         private_module_t* m = reinterpret_cast<private_module_t*>(
                 dev->common.module);
         const size_t bufferSize = m->finfo.line_length * m->info.yres;
         int index = (hnd->base - m->framebuffer->base) / bufferSize;
         m->bufferMask &= ~(1<<index); 
-    } 
+    } else { 
 #if HAVE_ANDROID_OS
-    else if (hnd->flags & private_handle_t::PRIV_FLAGS_USES_PMEM) 
-    {
-        if (hnd->fd >= 0) {
-            struct pmem_region sub = { hnd->offset, hnd->size };
-            int err = ioctl(hnd->fd, PMEM_UNMAP, &sub);
-            LOGE_IF(err<0, "PMEM_UNMAP failed (%s), "
-                    "fd=%d, sub.offset=%lu, sub.size=%lu",
-                    strerror(errno), hnd->fd, hnd->offset, hnd->size);
-            if (err == 0) {
-                // we can't deallocate the memory in case of UNMAP failure
-                // because it would give that process access to someone else's
-                // surfaces, which would be a security breach.
-                sAllocator.deallocate(hnd->offset);
+        if (hnd->flags & private_handle_t::PRIV_FLAGS_USES_PMEM) {
+            if (hnd->fd >= 0) {
+                struct pmem_region sub = { hnd->offset, hnd->size };
+                int err = ioctl(hnd->fd, PMEM_UNMAP, &sub);
+                LOGE_IF(err<0, "PMEM_UNMAP failed (%s), "
+                        "fd=%d, sub.offset=%lu, sub.size=%lu",
+                        strerror(errno), hnd->fd, hnd->offset, hnd->size);
+                if (err == 0) {
+                    // we can't deallocate the memory in case of UNMAP failure
+                    // because it would give that process access to someone else's
+                    // surfaces, which would be a security breach.
+                    sAllocator.deallocate(hnd->offset);
+                }
             }
         }
-    }
 #endif // HAVE_ANDROID_OS
+        gralloc_module_t* module = reinterpret_cast<gralloc_module_t*>(
+                dev->common.module);
+        terminateBuffer(module, const_cast<private_handle_t*>(hnd));
+    }
 
-    gralloc_module_t* m = reinterpret_cast<gralloc_module_t*>(
-            dev->common.module);
-    gralloc_unregister_buffer(m, handle);
-    
     close(hnd->fd);
     delete hnd;
     return 0;
diff --git a/modules/gralloc/gralloc_priv.h b/modules/gralloc/gralloc_priv.h
index aa757b1..bfd3635 100644
--- a/modules/gralloc/gralloc_priv.h
+++ b/modules/gralloc/gralloc_priv.h
@@ -37,12 +37,14 @@
 /*****************************************************************************/
 
 struct private_module_t;
+struct private_handle_t;
 
 inline size_t roundUpToPageSize(size_t x) {
     return (x + (PAGE_SIZE-1)) & ~(PAGE_SIZE-1);
 }
 
 int mapFrameBufferLocked(struct private_module_t* module);
+int terminateBuffer(gralloc_module_t const* module, private_handle_t* hnd);
 
 /*****************************************************************************/
 
diff --git a/modules/gralloc/mapper.cpp b/modules/gralloc/mapper.cpp
index 75a9bb6..323f5d8 100644
--- a/modules/gralloc/mapper.cpp
+++ b/modules/gralloc/mapper.cpp
@@ -75,7 +75,14 @@
 {
     private_handle_t* hnd = (private_handle_t*)handle;
     if (!(hnd->flags & private_handle_t::PRIV_FLAGS_FRAMEBUFFER)) {
-        if (munmap((void*)hnd->base, hnd->size) < 0) {
+        void* base = (void*)hnd->base;
+        size_t size = hnd->size;
+#if PMEM_HACK
+        base = (void*)(intptr_t(base) - hnd->offset);
+        size += hnd->offset;
+#endif
+        //LOGD("unmapping from %p, size=%d", base, size);
+        if (munmap(base, size) < 0) {
             LOGE("Could not unmap %s", strerror(errno));
         }
     }
@@ -144,6 +151,33 @@
     return 0;
 }
 
+int terminateBuffer(gralloc_module_t const* module,
+        private_handle_t* hnd)
+{
+    /*
+     * If the buffer has been mapped during a lock operation, it's time
+     * to un-map it. It's an error to be here with a locked buffer.
+     */
+
+    LOGE_IF(hnd->lockState & private_handle_t::LOCK_STATE_READ_MASK,
+            "handle %p still locked (state=%08x)",
+            hnd, hnd->lockState);
+    
+    if (hnd->lockState & private_handle_t::LOCK_STATE_MAPPED) {
+        // this buffer was mapped, unmap it now
+        if ((hnd->flags & private_handle_t::PRIV_FLAGS_USES_PMEM) && 
+            (hnd->pid == getpid())) {
+            // ... unless it's a "master" pmem buffer, that is a buffer
+            // mapped in the process it's been allocated.
+            // (see gralloc_alloc_buffer())
+        } else {
+            gralloc_unmap(module, hnd);
+        }
+    }
+
+    return 0;
+}
+
 int gralloc_lock(gralloc_module_t const* module,
         buffer_handle_t handle, int usage,
         int l, int t, int w, int h,