Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754965AbZGCJYV (ORCPT ); Fri, 3 Jul 2009 05:24:21 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752974AbZGCJYN (ORCPT ); Fri, 3 Jul 2009 05:24:13 -0400 Received: from mx3.mail.elte.hu ([157.181.1.138]:54210 "EHLO mx3.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752434AbZGCJYN (ORCPT ); Fri, 3 Jul 2009 05:24:13 -0400 Date: Fri, 3 Jul 2009 11:24:05 +0200 From: Ingo Molnar To: Kurt Garloff , "Maciej W. Rozycki" , Greg KH , x86@kernel.org, "H. Peter Anvin" , Thomas Gleixner , linux-kernel@vger.kernel.org, Yinghai Lu , Jesse Barnes Subject: Re: [PATCH] x86: sysctl to allow panic on IOCK NMI error Message-ID: <20090703092405.GD3902@elte.hu> References: <20090624213211.GA11291@kroah.com> <20090630223040.GA3802@suse.de> <20090701111003.GC15958@elte.hu> <20090703091935.GL20681@tpkurt2.suse.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20090703091935.GL20681@tpkurt2.suse.de> User-Agent: Mutt/1.5.18 (2008-05-17) X-ELTE-SpamScore: -1.5 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-1.5 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.2.5 -1.5 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1827 Lines: 46 * Kurt Garloff wrote: > Ingo, > > On Wed, Jul 01, 2009 at 01:10:03PM +0200, Ingo Molnar wrote: > > * Maciej W. Rozycki wrote: > > > > > On Tue, 30 Jun 2009, Greg KH wrote: > > > > > > > > These days an IOCK NMI typically happens in response to a PCI > > > > > SERR -- it may be useful to traverse PCI buses to find the > > > > > offender and dump this information on this occasion too. The > > > > > south bridge may have additional status too. > > > > > > > > Sure, that would be great to have. Care to make a patch? :) > > > > > > ENOTIME, sorry. Next year perhaps. Or a homework project for > > > one of the newbies. ;) > > > > You know that this project would kill a newbie, right? :) > > > > We have no real southbridge drivers on x86 - but we should > > certainly add some. Also, walking the PCI device tree from NMI > > context is tricky as the lists there are not NMI safe - we could > > crash if we happen to get a #IOCK while loading/unloading > > drivers (which is rare but could happen). > > Well -- in case we panic the system anyway this is not necessarily > a big issue (let's print the message before ...) -- if we crash > trying to gather additional info, we'll lose the info. Currently > we never have the info ... We dont _necessarily_ crash ... The crash/panic is default off and sysctl driven. Allowing a crash is not the highest quality of implementation and i'm somewhat wary of 'allow a little bit of crap' arguments - it's too similar to the 'little bit pregnant' concept ;-) Ingo -- 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/