From 255d0884f5635122adb23866b242b4ca112f4bc8 Mon Sep 17 00:00:00 2001 From: David Rientjes Date: Mon, 10 Feb 2014 14:25:39 -0800 Subject: [PATCH] mm/slub.c: list_lock may not be held in some circumstances Commit c65c1877bd68 ("slub: use lockdep_assert_held") incorrectly required that add_full() and remove_full() hold n->list_lock. The lock is only taken when kmem_cache_debug(s), since that's the only time it actually does anything. Require that the lock only be taken under such a condition. Reported-by: Larry Finger Tested-by: Larry Finger Tested-by: Paul E. McKenney Acked-by: Christoph Lameter Cc: Pekka Enberg Signed-off-by: David Rientjes Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/slub.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/mm/slub.c b/mm/slub.c index 7e3e0458bce4..3d3a8a7a0f8c 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -1004,21 +1004,19 @@ static inline void slab_free_hook(struct kmem_cache *s, void *x) static void add_full(struct kmem_cache *s, struct kmem_cache_node *n, struct page *page) { - lockdep_assert_held(&n->list_lock); - if (!(s->flags & SLAB_STORE_USER)) return; + lockdep_assert_held(&n->list_lock); list_add(&page->lru, &n->full); } static void remove_full(struct kmem_cache *s, struct kmem_cache_node *n, struct page *page) { - lockdep_assert_held(&n->list_lock); - if (!(s->flags & SLAB_STORE_USER)) return; + lockdep_assert_held(&n->list_lock); list_del(&page->lru); } -- 2.20.1