Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752974Ab2EaKst (ORCPT ); Thu, 31 May 2012 06:48:49 -0400 Received: from mx1.fusionio.com ([66.114.96.30]:51743 "EHLO mx1.fusionio.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751608Ab2EaKss (ORCPT ); Thu, 31 May 2012 06:48:48 -0400 X-ASG-Debug-ID: 1338461327-03d6a5031234270001-xx1T2L X-Barracuda-Envelope-From: JAxboe@fusionio.com Message-ID: <4FC74C59.2030100@fusionio.com> Date: Thu, 31 May 2012 12:47:53 +0200 From: Jens Axboe MIME-Version: 1.0 To: Eric Dumazet CC: Linus Torvalds , "linux-kernel@vger.kernel.org" , Tejun Heo , Alan Cox , Andrew Morton Subject: Re: [PATCH] block: avoid infinite loop in get_task_io_context() References: <4FC6189B.9080909@fusionio.com> <1338402812.2760.413.camel@edumazet-glaptop> <4FC66D3D.6080509@fusionio.com> <1338404902.2760.451.camel@edumazet-glaptop> <1338410107.2760.544.camel@edumazet-glaptop> <1338460706.2760.1330.camel@edumazet-glaptop> X-ASG-Orig-Subj: Re: [PATCH] block: avoid infinite loop in get_task_io_context() In-Reply-To: <1338460706.2760.1330.camel@edumazet-glaptop> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit X-Barracuda-Connect: mail1.int.fusionio.com[10.101.1.21] X-Barracuda-Start-Time: 1338461327 X-Barracuda-Encrypted: AES128-SHA X-Barracuda-URL: http://10.101.1.180:8000/cgi-mod/mark.cgi X-Barracuda-Bayes: INNOCENT GLOBAL 0.0000 1.0000 -2.0210 X-Barracuda-Spam-Score: -2.02 X-Barracuda-Spam-Status: No, SCORE=-2.02 using per-user scores of TAG_LEVEL=1000.0 QUARANTINE_LEVEL=1000.0 KILL_LEVEL=9.0 tests= X-Barracuda-Spam-Report: Code version 3.2, rules version 3.2.2.98524 Rule breakdown below pts rule name description ---- ---------------------- -------------------------------------------------- Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1596 Lines: 51 On 05/31/2012 12:38 PM, Eric Dumazet wrote: > From: Eric Dumazet > > On Wed, 2012-05-30 at 22:35 +0200, Eric Dumazet wrote: >> On Wed, 2012-05-30 at 21:08 +0200, Eric Dumazet wrote: >>> On Wed, 2012-05-30 at 20:55 +0200, Jens Axboe wrote: >>>> On 05/30/2012 08:33 PM, Eric Dumazet wrote: >>>>> On Wed, 2012-05-30 at 14:54 +0200, Jens Axboe wrote: >>>>>> Hi Linus, >>>>>> >>>>>> On top of the for-3.5/core pull request, here are the driver related >>>>>> changes for 3.5. It contains: >>>>> >>>>> Hi Jens >>>>> >>>>> Not sure if this is related, but latest Linus tree cannot boot anymore >>>>> here... >>>>> >>>>> BUG: soft lockup - CPU#3 stuck for 22s ! [mountall.1603] >>>> >>>> Hrmpf, can you attach your .config? >>>> >>> >>> I can do a bisection pretty fast I think >> >> Not sure if bisection was good, but result is : > > Bisection gave nothing, because its an old bug ? > > Following patch cures it. > > [PATCH] block: avoid infinite loop in get_task_io_context() > > Calling get_task_io_context() on a exiting task which isn't %current can > loop forever. This triggers at boot time on my dev machine. > > BUG: soft lockup - CPU#3 stuck for 22s ! [mountall.1603] Eric, do you have a task trace to go with this lockup, where task != current? In any case, it is a legit bug fix. I have applied it. -- Jens Axboe -- 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/