Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760117Ab0KRUEb (ORCPT ); Thu, 18 Nov 2010 15:04:31 -0500 Received: from casper.infradead.org ([85.118.1.10]:42916 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757681Ab0KRUE3 convert rfc822-to-8bit (ORCPT ); Thu, 18 Nov 2010 15:04:29 -0500 Subject: Re: [V2 PATCH 0/6] x86, NMI: give NMI handler a face-lift From: Peter Zijlstra To: Jason Wessel Cc: Don Zickus , Ingo Molnar , Robert Richter , ying.huang@intel.com, Andi Kleen , LKML , Frederic Weisbecker In-Reply-To: <4CE583D0.8050407@windriver.com> References: <20101112154231.GN4823@redhat.com> <4CDD6389.2080206@windriver.com> <20101112161144.GP4823@redhat.com> <4CDD6CAD.30303@windriver.com> <20101112172755.GR4823@redhat.com> <20101116184325.GB4823@redhat.com> <4CE2E3C3.6060800@windriver.com> <20101118080516.GJ32621@elte.hu> <4CE52048.5080802@windriver.com> <1290086232.2109.1507.camel@laptop> <20101118193247.GF18100@redhat.com> <4CE583D0.8050407@windriver.com> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8BIT Date: Thu, 18 Nov 2010 21:04:20 +0100 Message-ID: <1290110660.2109.1529.camel@laptop> Mime-Version: 1.0 X-Mailer: Evolution 2.30.3 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 755 Lines: 17 On Thu, 2010-11-18 at 13:51 -0600, Jason Wessel wrote: > I highly doubt we want to disable perf. I would rather use the source > and fix the nmi emulation in KVM/Qemu after we hear back the results > from Cyril because it sounds as if the problem is nearly bottomed out. Problem is that p6/p4/amd don't have cpuid bits telling us if there is a PMU (virt should clear those if it doesn't emulate one). I guess the safest course is to write a pmu msr and see if that faults, if it does, disable the thing. -- 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/