diff --git a/intern/cycles/render/session.cpp b/intern/cycles/render/session.cpp
index 94cb69102d2..7a40e0d04b6 100644
--- a/intern/cycles/render/session.cpp
+++ b/intern/cycles/render/session.cpp
@@ -132,6 +132,8 @@ bool Session::ready_to_reset()
 
 void Session::reset_gpu(BufferParams& buffer_params, int samples)
 {
+	thread_scoped_lock pause_lock(pause_mutex);
+
 	/* block for buffer acces and reset immediately. we can't do this
 	 * in the thread, because we need to allocate an OpenGL buffer, and
 	 * that only works in the main thread */
@@ -295,6 +297,7 @@ void Session::run_gpu()
 void Session::reset_cpu(BufferParams& buffer_params, int samples)
 {
 	thread_scoped_lock reset_lock(delayed_reset.mutex);
+	thread_scoped_lock pause_lock(pause_mutex);
 
 	display_outdated = true;
 	reset_time = time_dt();
@@ -484,7 +487,16 @@ void Session::run_cpu()
 			 * wait for pause condition notify to wake up again */
 			thread_scoped_lock pause_lock(pause_mutex);
 
-			if(pause || no_tiles) {
+			if(!pause && delayed_reset.do_reset) {
+				/* reset once to start */
+				thread_scoped_lock reset_lock(delayed_reset.mutex);
+				thread_scoped_lock buffers_lock(buffers_mutex);
+				thread_scoped_lock display_lock(display_mutex);
+
+				reset_(delayed_reset.params, delayed_reset.samples);
+				delayed_reset.do_reset = false;
+			}
+			else if(pause || no_tiles) {
 				update_status_time(pause, no_tiles);
 
 				while(1) {