From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754616Ab0CWXYe (ORCPT ); Tue, 23 Mar 2010 19:24:34 -0400 Received: from ogre.sisk.pl ([217.79.144.158]:41088 "EHLO ogre.sisk.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753381Ab0CWXYd (ORCPT ); Tue, 23 Mar 2010 19:24:33 -0400 From: "Rafael J. Wysocki" To: Stephane Eranian Subject: Re: 2.6.34-rc2 - crash on shutdown Date: Wed, 24 Mar 2010 00:27:33 +0100 User-Agent: KMail/1.12.4 (Linux/2.6.34-rc2-rjw; KDE/4.3.5; x86_64; ; ) Cc: Clemens Ladisch , David R , linux-kernel@vger.kernel.org References: <20100323090206.33932wop73sdefm6@unsolicited.net> <201003232318.11332.rjw@sisk.pl> In-Reply-To: MIME-Version: 1.0 Content-Type: Text/Plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <201003240027.33354.rjw@sisk.pl> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tuesday 23 March 2010, Stephane Eranian wrote: > On Tue, Mar 23, 2010 at 11:18 PM, Rafael J. Wysocki wrote: > > On Tuesday 23 March 2010, Clemens Ladisch wrote: > >> Stephane Eranian wrote: > >> > On Tue, Mar 23, 2010 at 1:02 PM, Clemens Ladisch wrote: > >> > > The only pointer access in this function is cpuhw->amd_nb, but > >> > > I don't see any obvious bugs. > >> > > >> > I reported a problem with the AMD initialization just last week. > >> > There is an issue with amd_pmu_cpu_online() which gets called > >> > too early, and thus fails. That leaves some bogus state and causes > >> > a crash in amd_pmu_cpu_offline(). > >> > > >> > I proposed a fix which was rejected. The alternative involves moving > >> > some the of CPU initialization code (on AMD) to an earlier position,i.e., > >> > which would be executed before the CPU_STARTED notifier. Nobody > >> > has proposed anything else so far. > >> > >> I don't know about the early bootmem stuff, but regardless of this issue, > >> if amd_pmu_cpu_online() can fail, then amd_pmu_cpu_offline() must be able > >> to handle this without blowing up. Something like this (untested): > > > > I guess we handle that already: > > > > http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=a90110c61073eab95d1986322693c2b9a8a6a5f6 > > > Ok, the fix avoids the crash but perf_events support for AMD is still broken. > > The root of the problem is elsewhere as I pointed out last week. Peter proposed > a patch today and I think this would be enough to avoid the crash and have > perf_events working again on AMD. Yes, I saw the Peter's patch. Thanks, Rafael