From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail190.messagelabs.com (mail190.messagelabs.com [216.82.249.51]) by kanga.kvack.org (Postfix) with SMTP id 675F5620002 for ; Wed, 23 Dec 2009 04:58:32 -0500 (EST) Message-ID: <4B31E9C3.6010109@linux.intel.com> Date: Wed, 23 Dec 2009 17:58:27 +0800 From: Haicheng Li MIME-Version: 1.0 Subject: [PATCH v2] slab: initialize unused alien cache entry as NULL at alloc_alien_cache(). References: <4B30BDA8.1070904@linux.intel.com> <1261521485.3000.1692.camel@calx> In-Reply-To: <1261521485.3000.1692.camel@calx> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org To: linux-mm@kvack.org Cc: Matt Mackall , Christoph Lameter , Pekka Enberg , andi@firstfloor.org, linux-kernel@vger.kernel.org List-ID: Memory hotplug would online new node in runtime, then reap timer will add this new node as a reap node. In such case, for each existing kmem_list, we need to ensure that the alien cache entry corresponding to this new added node is NULL. Otherwise, it might cause BUG when reap_alien() affecting the new added node. V2: use kzalloc_node() to ensure zeroed memory. CC: Pekka Enberg Acked-by: Andi Kleen Reviewed-by: Christoph Lameter Reviewed-by: Matt Mackall Signed-off-by: Haicheng Li --- mm/slab.c | 8 +++----- 1 files changed, 3 insertions(+), 5 deletions(-) diff --git a/mm/slab.c b/mm/slab.c index 7dfa481..000e9ed 100644 --- a/mm/slab.c +++ b/mm/slab.c @@ -966,18 +966,16 @@ static void *alternate_node_alloc(struct kmem_cache *, gfp_t); static struct array_cache **alloc_alien_cache(int node, int limit, gfp_t gfp) { struct array_cache **ac_ptr; - int memsize = sizeof(void *) * nr_node_ids; + int memsize = sizeof(void *) * MAX_NUMNODES; int i; if (limit > 1) limit = 12; - ac_ptr = kmalloc_node(memsize, gfp, node); + ac_ptr = kzalloc_node(memsize, gfp, node); if (ac_ptr) { for_each_node(i) { - if (i == node || !node_online(i)) { - ac_ptr[i] = NULL; + if (i == node || !node_online(i)) continue; - } ac_ptr[i] = alloc_arraycache(node, limit, 0xbaadf00d, gfp); if (!ac_ptr[i]) { for (i--; i >= 0; i--) -- 1.5.3.8 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org