fix RCU-callback-after-kmem_cache_destroy problem in sl[aou]b

Jesper noted that kmem_cache_destroy() invokes synchronize_rcu() rather than
rcu_barrier() in the SLAB_DESTROY_BY_RCU case, which could result in RCU
callbacks accessing a kmem_cache after it had been destroyed.

Cc: <stable@kernel.org>
Acked-by: Matt Mackall <mpm@selenic.com>
Reported-by: Jesper Dangaard Brouer <hawk@comx.dk>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
This commit is contained in:
Paul E. McKenney
2009-06-25 12:31:37 -07:00
committed by Pekka Enberg
parent 28d0325ce6
commit 7ed9f7e5db
3 changed files with 5 additions and 1 deletions

View File

@ -2595,6 +2595,8 @@ static inline int kmem_cache_close(struct kmem_cache *s)
*/
void kmem_cache_destroy(struct kmem_cache *s)
{
if (s->flags & SLAB_DESTROY_BY_RCU)
rcu_barrier();
down_write(&slub_lock);
s->refcount--;
if (!s->refcount) {