diff --git a/src/plugins/platforms/wayland/qwaylandwindow.cpp b/src/plugins/platforms/wayland/qwaylandwindow.cpp
index abc54f58438..95358232316 100644
--- a/src/plugins/platforms/wayland/qwaylandwindow.cpp
+++ b/src/plugins/platforms/wayland/qwaylandwindow.cpp
@@ -657,10 +657,11 @@ QMutex QWaylandWindow::mFrameSyncMutex;
 
 bool QWaylandWindow::waitForFrameSync(int timeout)
 {
-    QMutexLocker locker(&mFrameSyncMutex);
     if (!mWaitingForFrameCallback)
         return true;
 
+    QMutexLocker locker(&mFrameSyncMutex);
+
     wl_proxy_set_queue(reinterpret_cast<wl_proxy *>(mFrameCallback), mFrameQueue);
     mDisplay->dispatchQueueWhile(mFrameQueue, [&]() { return mWaitingForFrameCallback; }, timeout);