From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail203.messagelabs.com (mail203.messagelabs.com [216.82.254.243]) by kanga.kvack.org (Postfix) with ESMTP id CBDA26B0207 for ; Fri, 2 Apr 2010 03:06:39 -0400 (EDT) Date: Fri, 2 Apr 2010 09:06:29 +0200 From: Daniel Mack 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: Sender: owner-linux-mm@kvack.org 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 List-ID: 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, 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