Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759253Ab0DBHGo (ORCPT ); Fri, 2 Apr 2010 03:06:44 -0400 Received: from buzzloop.caiaq.de ([212.112.241.133]:49057 "EHLO buzzloop.caiaq.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759227Ab0DBHGi (ORCPT ); Fri, 2 Apr 2010 03:06:38 -0400 Date: Fri, 2 Apr 2010 09:06:29 +0200 From: Daniel Mack To: TAO HU Cc: linux-mm@kvack.org, Chang Qing-A21550 , "Ye Yuan.Bo-A22116" , linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org Subject: Re: [Question] race condition in mm/page_alloc.c regarding page->lru? Message-ID: <20100402070629.GT30801@buzzloop.caiaq.de> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1362 Lines: 31 On Fri, Apr 02, 2010 at 11:51:33AM +0800, TAO HU wrote: > On Thu, Apr 1, 2010 at 12:05 PM, TAO HU wrote: > > We got a panic on our ARM (OMAP) based HW. > > Our code is based on 2.6.29 kernel (last commit for mm/page_alloc.c is > > cc2559bccc72767cb446f79b071d96c30c26439b) > > > > It appears to crash while going through pcp->list in > > buffered_rmqueue() of mm/page_alloc.c after checking vmlinux. > > "00100100" implies LIST_POISON1 that suggests a race condition between > > list_add() and list_del() in my personal view. > > However we not yet figure out locking problem regarding page.lru. I'm sure this is just a memory corruption which is unrelated to code in the the memory management area. The code there just happens to trigger it as it is called frequently and is very sensitive to bogus data Did you see the other thread I started off yesterday? http://lkml.indiana.edu/hypermail/linux/kernel/1004.0/00157.html We could well see the same problem here. Not sure though as any kind of memory corruption ends up in Ooopses like the ones you see, but it could be a hint. Daniel -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/