Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933073AbcJTHVk (ORCPT ); Thu, 20 Oct 2016 03:21:40 -0400 Received: from Galois.linutronix.de ([146.0.238.70]:47051 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932629AbcJTHVi (ORCPT ); Thu, 20 Oct 2016 03:21:38 -0400 Date: Thu, 20 Oct 2016 09:17:50 +0200 (CEST) From: Thomas Gleixner To: Ingo Molnar cc: Linus Torvalds , Philipp Hahn , Chris Mason , Jens Axboe , Dave Jones , Al Viro , Josef Bacik , David Sterba , linux-btrfs , Linux Kernel Subject: Re: bio linked list corruption. In-Reply-To: <20161020065216.GB29032@gmail.com> Message-ID: References: <20161011144507.okg6baqvodn2m2lh@codemonkey.org.uk> <20161018224205.bjgloslaxcej2td2@codemonkey.org.uk> <20161018233148.GA93792@clm-mbp.masoncoding.com> <20161018234248.GB93792@clm-mbp.masoncoding.com> <9ba0cd0b-33f6-2156-aaf2-ad9ed9a00115@pmhahn.de> <20161020065216.GB29032@gmail.com> User-Agent: Alpine 2.20 (DEB 67 2015-01-07) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 758 Lines: 20 On Thu, 20 Oct 2016, Ingo Molnar wrote: > * Linus Torvalds wrote: > > So I don't think it's related. Yours looks like some subtle timer base > > race. It smells like a locking problem with timers. I'm not seeing > > what it might be, but it *might* have been fixed by doing the > > TIMER_MIGRATING bit right in add_timer_on() (commit 22b886dd1018). 4.1 does not have the new fangled timer wheel. So 22b886dd1018 is irrelevant. > > Adding some timer people just in case, but I don't think your 4.1 > > report is related. This looks like one of the classic issues where an enqueued timer gets freed/reinitialized or otherwise manipulated. So yes, Ingos recommendation for debugging is the right thing to do. Thanks, tglx