Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755279AbXJAT2R (ORCPT ); Mon, 1 Oct 2007 15:28:17 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752345AbXJAT2E (ORCPT ); Mon, 1 Oct 2007 15:28:04 -0400 Received: from www.tglx.de ([62.245.132.106]:58903 "EHLO www.tglx.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752182AbXJAT2C (ORCPT ); Mon, 1 Oct 2007 15:28:02 -0400 Date: Mon, 1 Oct 2007 21:27:39 +0200 (CEST) From: Thomas Gleixner To: Andi Kleen cc: David Bahi , linux-kernel@vger.kernel.org, linux-rt-users@vger.kernel.org, Gregory Haskins Subject: Re: nmi_watchdog fix for x86_64 to be more like i386 In-Reply-To: <200710012116.59356.ak@suse.de> Message-ID: References: <46FA4A800200006C000192FE@sinclair.provo.novell.com> <200710011936.01528.ak@suse.de> <200710012116.59356.ak@suse.de> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1437 Lines: 36 On Mon, 1 Oct 2007, Andi Kleen wrote: > On Monday 01 October 2007 20:54:21 Thomas Gleixner wrote: > > On Mon, 1 Oct 2007, Andi Kleen wrote: > > > > > On Wednesday 26 September 2007 20:03:12 David Bahi wrote: > > > > Thanks to tglx and ghaskins for all the help in tracking down a very > > > > early nmi_watchdog crash on certain x86_64 machines. > > > > > > The patch is totally bogus. irq 0 doesn't say anything about whether > > > the current CPU still works or not. You always need some local > > > interrupt. This basically disables the NMI watchdog for the non boot CPUs. > > > > > > It's even wrong on i386 -- i wonder how that broken patch > > > made it in there. I'll remove it there. > > > > Right, it's wrong for the broadcast case, but simply removing it will > > trigger false positives on the CPU which runs the broadcast timer. I > > fix this proper. > > I already did this here by checking for cpu != 0. But it also needs either tracking > or forbidding migrations of irq 0. I can take care of the patch. I was thinking about the same fix. On i386 we already have the irq migration / balancing of irq 0 disabled. That's why we setup IRQ0 with IRQ_NOBALANCING. tglx - 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/