Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759010Ab3FCQgn (ORCPT ); Mon, 3 Jun 2013 12:36:43 -0400 Received: from mail.candelatech.com ([208.74.158.172]:44405 "EHLO ns3.lanforge.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751005Ab3FCQgl (ORCPT ); Mon, 3 Jun 2013 12:36:41 -0400 Message-ID: <51ACC60B.8090504@candelatech.com> Date: Mon, 03 Jun 2013 09:36:27 -0700 From: Ben Greear Organization: Candela Technologies User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130311 Thunderbird/17.0.4 MIME-Version: 1.0 To: Joe Lawrence CC: Rusty Russell , Linux Kernel Mailing List , stable@vger.kernel.org Subject: Re: Please add to stable: module: don't unlink the module until we've removed all exposure. References: <51A8E884.1080009@candelatech.com> <87ehclumhr.fsf@rustcorp.com.au> <51ACBD6A.1030304@candelatech.com> In-Reply-To: <51ACBD6A.1030304@candelatech.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2063 Lines: 45 On 06/03/2013 08:59 AM, Ben Greear wrote: > On 06/03/2013 07:17 AM, Joe Lawrence wrote: > >>>> Hi Rusty, >>>> >>>> I had pointed Ben (offlist) to that bugzilla entry without realizing >>>> there were other earlier related fixes in this space. Re-viewing bz- >>>> 58011, it looks like it was opened against 3.8.12, while Ben and myself >>>> had encountered module loading problems in versions 3.9 and >>>> 3.9.[1-3]. I can update the bugzilla entry to add a comment noting commit >>>> a49b7e82 "kobject: fix kset_find_obj() race with concurrent last >>>> kobject_put()". >>>> >>>> That said, it doesn't appear that commit 944a1fa "module: don't unlink the >>>> module until we've removed all exposure" has not made it into any stable >>>> kernel. On my system, applying this on top of 3.9 resolved a module >>>> unload/load race that would occasionally occur on boot (two video adapters >>>> of the same make, the module unloads for whatever reason and I see "module >>>> is already loaded" and "sysfs: cannot create duplicate filename >>>> '/module/mgag200'" messages every 5-10% instances.) I have logs if you >>>> were interested in these warnings/crashes. > > It at least works around the problem for me as well. But, a more rare > migration/[0-3] (I think) related lockup still exists in 3.9.4 for me, > so I will also try applying that other kobject patch and continue testing > today... Well, that other kobject patch is already in 3.9.4, so I think it's still a good idea to include the "module: don't unlink the module until we've removed all exposure." patch in stable. I have a decent test case to reproduce the crash, so if someone wants me to test other patches instead, then I will do so. Thanks, Ben -- Ben Greear Candela Technologies Inc http://www.candelatech.com -- 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/