Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760597Ab0KRV0J (ORCPT ); Thu, 18 Nov 2010 16:26:09 -0500 Received: from mail-ey0-f174.google.com ([209.85.215.174]:36993 "EHLO mail-ey0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754896Ab0KRV0I (ORCPT ); Thu, 18 Nov 2010 16:26:08 -0500 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=date:from:to:cc:subject:message-id:references:mime-version :content-type:content-disposition:in-reply-to:user-agent; b=inIPLPKoWtWhtZeZh6zBn3ZVK42XwwyBYQKF+KXZotISjg2a61RcaL2NIgflhFaQ9n ZbNfOLor81gravgthBMbI7b9jPKiI8Ys9bTu56KZnBZW+6usqqAAB4Ex7ZCpLfDYmawS j9Qs6c3KCT0Hcms2MOrNF4pQ0Hwbbjw/rEi0Y= Date: Fri, 19 Nov 2010 00:26:04 +0300 From: Cyrill Gorcunov To: Don Zickus Cc: Jason Wessel , Peter Zijlstra , Ingo Molnar , Robert Richter , ying.huang@intel.com, Andi Kleen , LKML , Frederic Weisbecker Subject: Re: [V2 PATCH 0/6] x86, NMI: give NMI handler a face-lift Message-ID: <20101118212604.GH6028@lenovo> References: <20101118080516.GJ32621@elte.hu> <4CE52048.5080802@windriver.com> <1290086232.2109.1507.camel@laptop> <20101118193247.GF18100@redhat.com> <4CE583D0.8050407@windriver.com> <20101118200807.GC8131@redhat.com> <20101118201118.GC6028@lenovo> <20101118205203.GA11445@redhat.com> <20101118210159.GF6028@lenovo> <20101118211638.GA13139@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20101118211638.GA13139@redhat.com> User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1228 Lines: 35 On Thu, Nov 18, 2010 at 04:16:38PM -0500, Don Zickus wrote: > On Fri, Nov 19, 2010 at 12:01:59AM +0300, Cyrill Gorcunov wrote: > > On Thu, Nov 18, 2010 at 03:52:03PM -0500, Don Zickus wrote: > > ... > > > > > > > > ok, Don, but you mentioned there are false alarms on real P4 machine, right? > > > > > > Yeah, there are two problems. One is using kgdb tests on kvm guests. The > > > other is using kgdb tests on a bare metal p4 machine. > > > > > > Cheers, > > > Don > > > > > > > ok, thanks, Jason just confirmed it too. I thing if we run with kgdb armed > > it (kgdb) should obtain nmi handler first and perf only after. > > > > actually I'm not sure why p4 hangs here while core passes the test, most > > because p4 reads the wrong high register which comes back zero. This will > always set overflow=1, thus swallowing all NMI if something like the nmi > watchdog has perf active. > > Cheers, > Don > oh, damn, indeed! Thanks Don! I'll cook patch sortly. Cyrill -- 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/