From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758161Ab0EYONN (ORCPT ); Tue, 25 May 2010 10:13:13 -0400 Received: from 27.mail-out.ovh.net ([91.121.30.210]:59092 "HELO 27.mail-out.ovh.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1755432Ab0EYONL (ORCPT ); Tue, 25 May 2010 10:13:11 -0400 Message-ID: <4BFBDAF3.3020504@example.com> Date: Tue, 25 May 2010 16:13:07 +0200 From: Piotr Hosowicz Reply-To: piotr@hosowicz.com Organization: hosowicz.com User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.9) Gecko/20100515 Icedove/3.0.4 MIME-Version: 1.0 To: piotr@hosowicz.com CC: Peter Zijlstra , Ingo Molnar , linux-kernel@vger.kernel.org, Jens Axboe , Divyesh Shah , Andrew Morton Subject: Re: BUG: using smp_processor_id() in preemptible [00000000] code: icedove-bin/5449 References: <4BF9EC69.5030709@example.com> <1274777422.5882.591.camel@twins> <20100525094347.GA7881@elte.hu> <4BFB9F0A.9040803@example.com> <1274781655.5882.765.camel@twins> <4BFBA0F8.9090908@example.com> <4BFBA6A2.4070405@example.com> In-Reply-To: <4BFBA6A2.4070405@example.com> Content-Type: text/plain; charset=ISO-8859-2; format=flowed Content-Transfer-Encoding: 8bit X-Ovh-Tracer-Id: 15795531268202656114 X-Ovh-Remote: 83.6.191.44 (abbb44.neoplus.adsl.tpnet.pl) X-Ovh-Local: 213.186.33.20 (ns0.ovh.net) X-Spam-Check: DONE|U 0.5/N Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 25.05.2010 12:29, Piotr Hosowicz wrote: > On 25.05.2010 12:05, Piotr Hosowicz wrote: >> On 25.05.2010 12:00, Peter Zijlstra wrote: >>> On Tue, 2010-05-25 at 11:57 +0200, Piotr Hosowicz wrote: >>>> On 25.05.2010 11:43, Ingo Molnar wrote: >>>> >>>>> This doesnt fix the whole issue. cpu_clock() is local, while the >>>>> measurements >>>>> done in the blk code are global ... >>>>> >>>>> While the warning is fixed this way, the far more serious issue is >>>>> still >>>>> there: time can go backwards if two points of time measurement are on >>>>> different CPUs and can mess up the statistics with negative values, >>>>> etc... >>>> >>>> How serious is this? Can it damage my data? I ask because the >>>> machine is >>>> my private computer, not any test machine. >>> >>> I'm not sure, since I didn't really look what they use the timestamps >>> for, but a guess would say your data is safe, it might schedule the io >>> funny, but it should not compromise integrity. At best its used purely >>> for statistics and not even behaviour is affected. >> >> Thanks. > > Seems to work like a charm. Not exactly. I looked into the syslog. I's much better, but I rebooted to single user mode to rebuild nvidia driver (new beta version) and I see same error (BUG ... code: ???) on shuting down, mentioning sync, umount and finally shutdown. Anyway it's much more comfortable to build nvidia drivers in the console because previously the BUG lines cluttered all the console. Regards, Piotr Hosowicz -- Z cyklu "Uroki demokracji", czyli pytania i odpowiedzi w teledurniejach: - Co wydarzyło się w Dallas 22 listopada 1963 roku? - Nie wiem, wtedy nie oglądałem. NP: Slash - Paradise City (Feat. Fergie And Cypress Hill) (Australian Bonus) NB: 2.6.34-20100524-1752-patched