From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753194AbcEPNHb (ORCPT ); Mon, 16 May 2016 09:07:31 -0400 Received: from mx1.redhat.com ([209.132.183.28]:53673 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751534AbcEPNH3 (ORCPT ); Mon, 16 May 2016 09:07:29 -0400 Date: Mon, 16 May 2016 09:07:27 -0400 From: Vivek Goyal To: Daniel Axtens Cc: linux-fsdevel@vger.kernel.org, linux-unionfs@vger.kernel.org, linux-kernel@vger.kernel.org, mpe@ellerman.id.au, mszeredi@redhat.com, dchinner@redhat.com Subject: Re: 45aebeaf4f67 "ovl: Ensure upper filesystem supports d_type" breaking Docker Message-ID: <20160516130727.GA26411@redhat.com> References: <87d1ombix6.fsf@gamma.ozlabs.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <87d1ombix6.fsf@gamma.ozlabs.ibm.com> User-Agent: Mutt/1.6.0 (2016-04-01) X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.32]); Mon, 16 May 2016 13:07:29 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, May 16, 2016 at 04:45:09PM +1000, Daniel Axtens wrote: > Hi, > > I installed a fresh 4.6.0 kernel on my ppc64le system, and tried to run > a docker container. It failed. > > Docker gave me errors like this: > > docker: Error response from daemon: error creating overlay mount to /var/lib/docker/overlay/2bc07cedad2770da2f384d5c1e81a6f45fa3c44a7658f10d02e5973ef76620fc-init/merged: invalid argument. > > In dmesg, I'm seeing: > > overlayfs: upper fs needs to support d_type. > Hi Daniel, What't the underlying fs you are using. overlayfs requires underlying filesystem to support d_type and there were cases where xfs was built with ftype=0 and in that case xfs does not support d_type. That means it led to issues like whiteouts not being recognized and being left behind during various operations. So it became clear that we need a check at mount time to make sure d_type is supported otherwise error out. This will require users to do mkfs.xfs with ftype=1 to make progress. I think new defaults for mkfs.xfs are such that ftype=1 is set. I am not sure which version that change was made in. Thanks Vivek > Reverting 45aebeaf4f67 ("ovl: Ensure upper filesystem supports d_type") > fixes the issue for me. I haven't investigated the root cause yet - at a > guess I'd say either Docker's layering system, or some weird interaction > with namespacing, maybe? I'll have a look when I get a spare moment. > > For reference, I'm using docker 1.11.0-dev. > > Regards, > Daniel Axtens