From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755341Ab3CPWGQ (ORCPT ); Sat, 16 Mar 2013 18:06:16 -0400 Received: from mail-wi0-f171.google.com ([209.85.212.171]:56449 "EHLO mail-wi0-f171.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751480Ab3CPWGP (ORCPT ); Sat, 16 Mar 2013 18:06:15 -0400 MIME-Version: 1.0 In-Reply-To: References: <20130315132607.GA4565@quad> Date: Sat, 16 Mar 2013 18:06:13 -0400 Message-ID: Subject: Re: [PATCH] perf,x86: fix kernel crash with PEBS/BTS after suspend/resume From: Parag Warudkar To: Linus Torvalds Cc: Stephane Eranian , Linux Kernel Mailing List , Peter Zijlstra , Ingo Molnar , Thomas Gleixner , Andrew Morton , Arnaldo Carvalho de Melo , Jiri Olsa , Andi Kleen Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Mar 16, 2013 at 1:56 PM, Linus Torvalds wrote: > On Sat, Mar 16, 2013 at 9:11 AM, Parag Warudkar wrote: >> >> This seems to trigger a WARN_ON during suspend/resume. > > Ugh, yes. It's practically harmless, but it's ugly and technically > wrong (we're using wrmsr_on_cpu() on our current cpu, but in a context > where using it on anything else would be horribly broken). > > I think the attached patch should fix it. UNTESTED! Applied and that seems to have suppressed the warning. Unrelated to this now it dies in intel_pstate_timer_func doing what seems to be a divide by zero. Hopefully I will be able to capture the oops on camera next time. Thanks, Parag