From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <linux-kernel-owner@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
	id S1758165Ab2AESi7 (ORCPT <rfc822;w@1wt.eu>);
	Thu, 5 Jan 2012 13:38:59 -0500
Received: from mail-iy0-f174.google.com ([209.85.210.174]:42413 "EHLO
	mail-iy0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
	with ESMTP id S1757259Ab2AESir (ORCPT
	<rfc822;linux-kernel@vger.kernel.org>);
	Thu, 5 Jan 2012 13:38:47 -0500
Date: Thu, 5 Jan 2012 10:38:42 -0800
From: Tejun Heo <tj@kernel.org>
To: Hugh Dickins <hughd@google.com>
Cc: Jens Axboe <axboe@kernel.dk>, Shaohua Li <shaohua.li@intel.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Stephen Rothwell <sfr@canb.auug.org.au>, linux-next@vger.kernel.org,
        LKML <linux-kernel@vger.kernel.org>, linux-scsi@vger.kernel.org,
        linux-ide@vger.kernel.org, x86@kernel.org
Subject: Re: [PATCH block/for-3.3/core] block: an exiting task should be
 allowed to create io_context
Message-ID: <20120105183842.GF18486@google.com>
References: <CAOS58YOzUcZz41+H+7dk5FteHy+Ufrtpk9dvdPqX6eie-GHi0Q@mail.gmail.com>
 <20111228211918.GA3516@google.com>
 <20120103173500.GB31746@google.com>
 <20120103175922.GC31746@google.com>
 <20120103200906.GG31746@google.com>
 <4F03631C.8080501@kernel.dk>
 <20120103221301.GH31746@google.com>
 <20120103223505.GI31746@google.com>
 <20120105012445.GP31746@google.com>
 <alpine.LSU.2.00.1201051026090.2009@eggly.anvils>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <alpine.LSU.2.00.1201051026090.2009@eggly.anvils>
User-Agent: Mutt/1.5.20 (2009-06-14)
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

Hello, Hugh.

On Thu, Jan 05, 2012 at 10:36:21AM -0800, Hugh Dickins wrote:
> I can vouch that it makes the list_debug.c:53 warnings go away: they
> used to come in half an hour, but I've run on two machines for 10
> hours so far without seeing any.

Yeah, my overnight test is pretty conclusive too.  I can usually hit
the bug under 30mins without the patch.

> And I've not yet seen a cfq-iosched.c:2585 with that patch in; but
> those were more elusive - we'll have to run until tomorrow night
> before concluding that it makes those go away too.
> 
> Or if you understand the connection between these, and would prefer
> to assume that it fixes them both, and want me to try another patch
> instead (I assume the one I'm running with is a workaround to narrow
> down the issue, rather than an intended fix?), let me know and I'll
> switch over.

Yeap, I can see the connections now and think I know where the bug is
too.  I'll, hopefully, be able to post fix soon.

Thanks.

-- 
tejun