diff --git a/drivers/gpu/drm/drm_irq.c b/drivers/gpu/drm/drm_irq.c
index 4bb7d34ff79eb4c8ae5fe949a1bf1d860bb4de68..65a45ce70e2a2a077c4f4dd424dd9b8c86def666 100644
--- a/drivers/gpu/drm/drm_irq.c
+++ b/drivers/gpu/drm/drm_irq.c
@@ -1682,7 +1682,7 @@ bool drm_handle_vblank(struct drm_device *dev, int crtc)
 	struct timeval tvblank;
 	unsigned long irqflags;
 
-	if (!dev->num_crtcs)
+	if (WARN_ON_ONCE(!dev->num_crtcs))
 		return false;
 
 	if (WARN_ON(crtc >= dev->num_crtcs))