From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from relay.sgi.com (relay1.sgi.com [192.48.171.29]) by ozlabs.org (Postfix) with ESMTP id 448B8DDEA0 for ; Wed, 23 Jan 2008 10:12:29 +1100 (EST) Date: Tue, 22 Jan 2008 15:12:20 -0800 (PST) From: Christoph Lameter To: Pekka Enberg Subject: Re: crash in kmem_cache_init In-Reply-To: <47967560.8080101@cs.helsinki.fi> Message-ID: References: <20080117211511.GA25320@aepfle.de> <20080118213011.GC10491@csn.ul.ie> <20080118225713.GA31128@aepfle.de> <20080122195448.GA15567@csn.ul.ie> <20080122212654.GB15567@csn.ul.ie> <20080122225046.GA866@csn.ul.ie> <47967560.8080101@cs.helsinki.fi> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Cc: lee.schermerhorn@hp.com, Olaf Hering , Linux MM , Mel Gorman , linux-kernel@vger.kernel.org, linuxppc-dev@ozlabs.org, "Aneesh Kumar K.V" , hanth Aravamudan , akpm@linux-foundation.org, KAMEZAWA Hiroyuki List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Wed, 23 Jan 2008, Pekka Enberg wrote: > When we call fallback_alloc() because the current node has ->nodelists set to > NULL, we end up calling kmem_getpages() with -1 as the node id which is then > translated to numa_node_id() by alloc_pages_node. But the reason we called > fallback_alloc() in the first place is because numa_node_id() doesn't have a > ->nodelist which makes cache_grow() oops. Right, if nodeid == -1 then we need to call alloc_pages... Essentiall a revert of 50c85a19e7b3928b5b5188524c44ffcbacdd4e35 from 2005. But I doubt that this is it. The fallback logic was added later and it worked fine. --- mm/slab.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) Index: linux-2.6/mm/slab.c =================================================================== --- linux-2.6.orig/mm/slab.c 2008-01-22 15:05:26.185452369 -0800 +++ linux-2.6/mm/slab.c 2008-01-22 15:05:59.301637009 -0800 @@ -1668,7 +1668,11 @@ static void *kmem_getpages(struct kmem_c if (cachep->flags & SLAB_RECLAIM_ACCOUNT) flags |= __GFP_RECLAIMABLE; - page = alloc_pages_node(nodeid, flags, cachep->gfporder); + if (nodeid == -1) + page = alloc_pages(flags, cachep->gfporder); + else + page = alloc_pages_node(nodeid, flags, cachep->gfporder); + if (!page) return NULL;