diff options
| author | Paul E. McKenney <paulmck@linux.vnet.ibm.com> | 2009-06-25 12:31:37 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2009-07-30 16:05:58 -0700 |
| commit | c6e23180eed05084ec631b2d2de0e94df8b48c74 (patch) | |
| tree | e3e4ecaad1ca3be4c035ee32ffcc8677fc85f7dd | |
| parent | 940a9e0f721c8498ebc23888171dac7046660278 (diff) | |
fix RCU-callback-after-kmem_cache_destroy problem in sl[aou]b
commit 7ed9f7e5db58c6e8c2b4b738a75d5dcd8e17aad5 upstream.
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.
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| -rw-r--r-- | mm/slab.c | 2 | ||||
| -rw-r--r-- | mm/slob.c | 2 | ||||
| -rw-r--r-- | mm/slub.c | 2 |
3 files changed, 5 insertions, 1 deletions
diff --git a/mm/slab.c b/mm/slab.c index e76eee46688..600e8649629 100644 --- a/mm/slab.c +++ b/mm/slab.c @@ -2580,7 +2580,7 @@ void kmem_cache_destroy(struct kmem_cache *cachep) } if (unlikely(cachep->flags & SLAB_DESTROY_BY_RCU)) - synchronize_rcu(); + rcu_barrier(); __kmem_cache_destroy(cachep); mutex_unlock(&cache_chain_mutex); diff --git a/mm/slob.c b/mm/slob.c index cb675d12679..ed04252cba5 100644 --- a/mm/slob.c +++ b/mm/slob.c @@ -561,6 +561,8 @@ EXPORT_SYMBOL(kmem_cache_create); void kmem_cache_destroy(struct kmem_cache *c) { + if (c->flags & SLAB_DESTROY_BY_RCU) + rcu_barrier(); slob_free(c, sizeof(struct kmem_cache)); } EXPORT_SYMBOL(kmem_cache_destroy); diff --git a/mm/slub.c b/mm/slub.c index 0c83e6afe7b..f0175b454c7 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -2447,6 +2447,8 @@ 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) { |