diff --git a/drivers/gpu/drm/mediatek/mtk_drm_gem.c b/drivers/gpu/drm/mediatek/mtk_drm_gem.c
index b04a3c2b111e..7ff6de44a9fa 100644
--- a/drivers/gpu/drm/mediatek/mtk_drm_gem.c
+++ b/drivers/gpu/drm/mediatek/mtk_drm_gem.c
@@ -284,6 +284,6 @@ void mtk_drm_gem_prime_vunmap(struct drm_gem_object *obj, void *vaddr)
 		return;
 
 	vunmap(vaddr);
-	mtk_gem->kvaddr = 0;
+	mtk_gem->kvaddr = NULL;
 	kfree(mtk_gem->pages);
 }