diff --git a/mm/slub.c b/mm/slub.c
index 3098e0cf2899..c6d603648c79 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -449,6 +449,7 @@ static DEFINE_SPINLOCK(object_map_lock);
  * not vanish from under us.
  */
 static unsigned long *get_map(struct kmem_cache *s, struct page *page)
+	__acquires(&object_map_lock)
 {
 	void *p;
 	void *addr = page_address(page);