diff --git a/include/drm/drm_atomic_helper.h b/include/drm/drm_atomic_helper.h
index 547480692470b6d43cbba01747bbd950573cdf3a..b464d4aeef82ea3c58f009c8eca35f4e012821c3 100644
--- a/include/drm/drm_atomic_helper.h
+++ b/include/drm/drm_atomic_helper.h
@@ -86,7 +86,8 @@ void
 drm_atomic_helper_disable_planes_on_crtc(struct drm_crtc_state *old_crtc_state,
 					 bool atomic);
 
-int drm_atomic_helper_swap_state(struct drm_atomic_state *state, bool stall);
+int __must_check drm_atomic_helper_swap_state(struct drm_atomic_state *state,
+					      bool stall);
 
 /* nonblocking commit helpers */
 int drm_atomic_helper_setup_commit(struct drm_atomic_state *state,