diff --git a/drivers/gpu/drm/nouveau/nvkm/core/memory.c b/drivers/gpu/drm/nouveau/nvkm/core/memory.c
index 29f4b4070b5579e6d48b9ab2864a60f25fdec1c6..e85a08ecd9da578d51fd778f171ea07e55bf9bb1 100644
--- a/drivers/gpu/drm/nouveau/nvkm/core/memory.c
+++ b/drivers/gpu/drm/nouveau/nvkm/core/memory.c
@@ -64,6 +64,7 @@ nvkm_memory_tags_get(struct nvkm_memory *memory, struct nvkm_device *device,
 		}
 
 		refcount_inc(&tags->refcount);
+		mutex_unlock(&fb->subdev.mutex);
 		*ptags = tags;
 		return 0;
 	}