From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755928AbcHWU7G (ORCPT ); Tue, 23 Aug 2016 16:59:06 -0400 Received: from fbr04.mfg.siteprotect.com ([64.26.60.139]:37796 "EHLO fbr04.mfg.siteprotect.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750899AbcHWU7F (ORCPT ); Tue, 23 Aug 2016 16:59:05 -0400 X-Greylist: delayed 388 seconds by postgrey-1.27 at vger.kernel.org; Tue, 23 Aug 2016 16:59:05 EDT Date: Tue, 23 Aug 2016 16:55:19 -0400 (EDT) From: Vince Weaver X-X-Sender: vince@pianoman.cluster.toy To: Alexander Shishkin cc: Peter Zijlstra , Ingo Molnar , linux-kernel@vger.kernel.org, eranian@google.com, Arnaldo Carvalho de Melo Subject: Re: [PATCH 0/3] perf, bts: Fallout from the fuzzer for perf/urgent In-Reply-To: <87shtvl8c5.fsf@ashishki-desk.ger.corp.intel.com> Message-ID: References: <1471942474-1854-1-git-send-email-alexander.shishkin@linux.intel.com> <87shtvl8c5.fsf@ashishki-desk.ger.corp.intel.com> User-Agent: Alpine 2.11 (DEB 23 2013-08-11) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-CTCH-Spam: Unknown X-CTCH-RefID: str=0001.0A020203.57BCB774.0145,ss=1,re=0.000,recu=0.000,reip=0.000,cl=1,cld=1,fgs=0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 23 Aug 2016, Alexander Shishkin wrote: > Vince Weaver writes: > > > On Tue, 23 Aug 2016, Alexander Shishkin wrote: > > > >> Recently Vince has reported warnings and panics coming from the > >> general direction of AUX tracing. I found two bugs which manifest > >> similarly, one in intel_bts driver and one in AUX unmapping path. > >> > >> Both are triggered by racing SET_OUTPUT against mmap_close while > >> running AUX tracing. I have a test case that set fire to the kernel > >> within a few seconds by doing this, which I can share if anyone > >> cares. > > > > I've applied these and am fuzzing on my Haswell machine and I'm getting > > lots and lots of > > > > [ 945.536374] Dazed and confused, but trying to continue > > [ 945.542391] Uhhuh. NMI received for unknown reason 21 on CPU 2. > > [ 945.549360] Do you have a strange power saving mode enabled? > > [ 945.556701] Dazed and confused, but trying to continue > > [ 945.563643] Uhhuh. NMI received for unknown reason 31 on CPU 2. > > [ 945.571379] Do you have a strange power saving mode enabled? > > [ 945.578754] Dazed and confused, but trying to continue > > [ 945.630889] Uhhuh. NMI received for unknown reason 31 on CPU 2. > > [ 945.638141] Do you have a strange power saving mode enabled? > > [ 945.645523] Dazed and confused, but trying to continue > > > > messages that I wasn't getting before. Of course, I updated from -rc2 to > > -rc3 before applying the patch so it could also be related to that too, I > > can try backing out the patches and see if it still happens. > > Uhhuh, that's not cool, let me look some more. But it should stop dying > on bts/aux stuff at least. Just wanted to say that when I backed out these patches the NMI errors went away, so they do seem to be a result of this patch series. Vince