From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755135AbbIBPdA (ORCPT ); Wed, 2 Sep 2015 11:33:00 -0400 Received: from mail-yk0-f173.google.com ([209.85.160.173]:36820 "EHLO mail-yk0-f173.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751678AbbIBPc6 (ORCPT ); Wed, 2 Sep 2015 11:32:58 -0400 Date: Wed, 2 Sep 2015 11:32:55 -0400 From: Tejun Heo To: Josh Boyer Cc: Jeff Moyer , msnitzer@redhat.com, "Richard W.M. Jones" , Li Zefan , Johannes Weiner , cgroups@vger.kernel.org, "Linux-Kernel@Vger. Kernel. Org" Subject: Re: __blkg_lookup oops with 4.2-rcX Message-ID: <20150902153255.GH22326@mtj.duckdns.org> References: <20150902145307.GG22326@mtj.duckdns.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20150902145307.GG22326@mtj.duckdns.org> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, On Wed, Sep 02, 2015 at 10:53:07AM -0400, Tejun Heo wrote: > On Sun, Aug 30, 2015 at 08:30:41AM -0400, Josh Boyer wrote: > I think the offending commit is 776687bce42b ("block, blk-mq: draining > can't be skipped even if bypass_depth was non-zero"). It looks like > the patch makes shutdown path travel data structure which is already > destroyed. Will post the fix soon. Hmm... I can't reproduce it here or see how such oops would happen. * Is the problem reproducible on v4.2? If so, can you please describe the steps to reproduce? How is cgroup set up? * Can you please run gdb or addr2line on it and report which line is causing the oops? Thanks. -- tejun