From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934160AbdCUTpX (ORCPT ); Tue, 21 Mar 2017 15:45:23 -0400 Received: from scorn.kernelslacker.org ([45.56.101.199]:58992 "EHLO scorn.kernelslacker.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932980AbdCUTpU (ORCPT ); Tue, 21 Mar 2017 15:45:20 -0400 Date: Tue, 21 Mar 2017 15:45:06 -0400 From: Dave Jones To: Thomas Gleixner Cc: Linux Kernel , Steven Rostedt Subject: Re: run_timer_softirq gpf. tracing? Message-ID: <20170321194506.hokyb24uqfq7hwf2@codemonkey.org.uk> Mail-Followup-To: Dave Jones , Thomas Gleixner , Linux Kernel , Steven Rostedt References: <20170321181710.5hoxel4ss4z55xew@codemonkey.org.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: NeoMutt/20170306 (1.8.0) X-Spam-Note: SpamAssassin invocation failed Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Mar 21, 2017 at 08:25:39PM +0100, Thomas Gleixner wrote: > > RAX looks like list poison, and CR2 = 4, which is likely the ->next of a list, > > with a NULL pointer. > > Certainly not on 64 bit. that would be 8. And CR2 is irrelevant here > because that's a #GP not a #PF. doh! > The timer which expires has timer->entry.next == POISON2 ! > > This has nothing to do with tracing, it's a classic list corruption. The > bad news is that there is no trace of the culprit because that happens when > some other timer expires after some random amount of time. ah! Thanks for putting me back on the right path. > If that is reproducible, then please enable debugobjects. That should > pinpoint the culprit. hit it twice today so far, so hopefully it'll reproduce. thanks. Dave