From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932339AbZDCOde (ORCPT ); Fri, 3 Apr 2009 10:33:34 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756612AbZDCOdV (ORCPT ); Fri, 3 Apr 2009 10:33:21 -0400 Received: from mtagate5.uk.ibm.com ([195.212.29.138]:51426 "EHLO mtagate5.uk.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754976AbZDCOdU (ORCPT ); Fri, 3 Apr 2009 10:33:20 -0400 Date: Fri, 3 Apr 2009 16:32:08 +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: <20090403143208.GA10005@schmichrtp.de.ibm.com> References: <20090324071730.53D7118C7A2@pentland.suse.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20090324071730.53D7118C7A2@pentland.suse.de> 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 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? -- Christof Schmitt