From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758966Ab0EYOew (ORCPT ); Tue, 25 May 2010 10:34:52 -0400 Received: from 27.mail-out.ovh.net ([91.121.30.210]:39366 "HELO 27.mail-out.ovh.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1758228Ab0EYOev (ORCPT ); Tue, 25 May 2010 10:34:51 -0400 Message-ID: <4BFBE004.5060101@example.com> Date: Tue, 25 May 2010 16:34:44 +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> <4BFBDAF3.3020504@example.com> In-Reply-To: <4BFBDAF3.3020504@example.com> Content-Type: text/plain; charset=ISO-8859-2; format=flowed Content-Transfer-Encoding: 7bit X-Ovh-Tracer-Id: 16160322839576998258 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 16:13, Piotr Hosowicz wrote: > 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. Sorry, reversed order - shutdown, umount, finally sync. -- - Czy jest cukier w kostkach ? - Nie ma. - A jakas inna tania bombonierka? Dla tesciowej. NP: Chickenfoot - Soap On A Rope NB: 2.6.34-20100524-1752-patched