diff --git a/drivers/gpu/drm/nouveau/nv50_display.c b/drivers/gpu/drm/nouveau/nv50_display.c
index a7663249b3baf2df1c5c75d87d3b32109984ba97..06e564a9ccb253b3018b45d2f0a96cc53430ab2c 100644
--- a/drivers/gpu/drm/nouveau/nv50_display.c
+++ b/drivers/gpu/drm/nouveau/nv50_display.c
@@ -2107,7 +2107,8 @@ nv50_head_atomic_check(struct drm_crtc *crtc, struct drm_crtc_state *state)
 					asyc->set.dither = true;
 			}
 		} else {
-			asyc->set.mask = ~0;
+			if (asyc)
+				asyc->set.mask = ~0;
 			asyh->set.mask = ~0;
 		}