Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753415AbZGCIAR (ORCPT ); Fri, 3 Jul 2009 04:00:17 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751535AbZGCIAH (ORCPT ); Fri, 3 Jul 2009 04:00:07 -0400 Received: from mx3.mail.elte.hu ([157.181.1.138]:41090 "EHLO mx3.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751118AbZGCIAG (ORCPT ); Fri, 3 Jul 2009 04:00:06 -0400 Date: Fri, 3 Jul 2009 09:59:24 +0200 From: Ingo Molnar To: Borislav Petkov Cc: "Maciej W. Rozycki" , Greg KH , x86@kernel.org, "H. Peter Anvin" , Thomas Gleixner , Kurt Garloff , linux-kernel@vger.kernel.org, Yinghai Lu , Jesse Barnes , Doug Thompson , Dave Jiang Subject: Re: [PATCH] x86: sysctl to allow panic on IOCK NMI error Message-ID: <20090703075924.GB13505@elte.hu> References: <20090624213211.GA11291@kroah.com> <20090630223040.GA3802@suse.de> <20090701111003.GC15958@elte.hu> <20090702075305.GC19187@elte.hu> <20090702104111.GA24940@aftab> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20090702104111.GA24940@aftab> 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: 1177 Lines: 29 * Borislav Petkov wrote: > On Thu, Jul 02, 2009 at 09:53:05AM +0200, Ingo Molnar wrote: > > > That shouldn't be a problem if we were about to panic(). For a > > > more sophisticated attempt of recovery -- yes, that would have to > > > be addressed. > > > > We are only panic-ing if the sysctl is set. The diagnostics > > would be useful anyway. The proper approach would be to defer it > > a bit in the non-panic case an read it out from some friendlier > > context - such as the EDAC core. > > Quickly skimming through code shows some functionality is there: > drivers/edac/edac_pci{,_sysfs}.c but doesn't seem to be NMI safe. > CCing some more people. the 'defer' would mean we put it into a softirq context or so and do it from there - not from NMI context. But yes, if we are about to panic due to this and want to print out something useful, making EDAC NMI safe would be nice. 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/