From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757225AbZDWIVv (ORCPT ); Thu, 23 Apr 2009 04:21:51 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755619AbZDWIVO (ORCPT ); Thu, 23 Apr 2009 04:21:14 -0400 Received: from mtagate7.uk.ibm.com ([195.212.29.140]:60851 "EHLO mtagate7.uk.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755832AbZDWIVL (ORCPT ); Thu, 23 Apr 2009 04:21:11 -0400 Date: Thu, 23 Apr 2009 10:21:08 +0200 From: Christof Schmitt To: Jens Axboe Cc: James Bottomley , linux-kernel@vger.kernel.org, linux-scsi@vger.kernel.org, Hannes Reinecke Subject: Re: [PATCH] block: fix intermittent dm timeout based oops Message-ID: <20090423082108.GA4376@schmichrtp.de.ibm.com> References: <20090324071730.53D7118C7A2@pentland.suse.de> <20090403143208.GA10005@schmichrtp.de.ibm.com> <20090403180106.GA5178@kernel.dk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20090403180106.GA5178@kernel.dk> User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Apr 03, 2009 at 08:01:06PM +0200, Jens Axboe wrote: > On Fri, Apr 03 2009, Christof Schmitt wrote: > > On Tue, Mar 24, 2009 at 08:17:30AM +0100, Hannes Reinecke wrote: > > > Very rarely under stress testing of dm, oopses are occuring as > > > something tampers with an old stack frame. This has been traced back > > > to blk_abort_queue() leaving a timeout_list pointing to the stack. > > > The reason is that sometimes blk_abort_request() won't delete the > > > timer (if the request is marked as complete but before the timer has > > > been removed, a small race window). Fix this by splicing back from > > > the ususally empty list to the q->timeout_list. > > > > > > Signed-off-by: Hannes Reinecke > > > --- > > > block/blk-timeout.c | 6 ++++++ > > > 1 files changed, 6 insertions(+), 0 deletions(-) > > > > > > diff --git a/block/blk-timeout.c b/block/blk-timeout.c > > > index bbbdc4b..6213123 100644 > > > --- a/block/blk-timeout.c > > > +++ b/block/blk-timeout.c > > > @@ -224,6 +224,12 @@ void blk_abort_queue(struct request_queue *q) > > > list_for_each_entry_safe(rq, tmp, &list, timeout_list) > > > blk_abort_request(rq); > > > > > > + /* > > > + * Occasionally, blk_abort_request() will return without > > > + * deleting the element from the list > > > + */ > > > + list_splice(&list, &q->timeout_list); > > > + > > > spin_unlock_irqrestore(q->queue_lock, flags); > > > > > > } > > > -- > > > 1.5.3.2 > > > > I just noticed that this fix is not upstream yet and i have seen test > > cases hitting this problem. > > > > Jens, are you going to included this patch, or should this go through > > the SCSI tree? > > I will include it, and CC stable as well. Any update on this? 2.6.30-rc3 does not have the patch. -- Christof Schmitt