From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932713Ab1AMCeQ (ORCPT ); Wed, 12 Jan 2011 21:34:16 -0500 Received: from TYO202.gate.nec.co.jp ([202.32.8.206]:51829 "EHLO tyo202.gate.nec.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932538Ab1AMCeM (ORCPT ); Wed, 12 Jan 2011 21:34:12 -0500 Message-ID: <4D2E6129.8000700@ce.jp.nec.com> Date: Thu, 13 Jan 2011 11:19:21 +0900 From: "Jun'ichi Nomura" User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.2.13) Gecko/20101209 Fedora/3.1.7-0.35.b3pre.fc14 Thunderbird/3.1.7 MIME-Version: 1.0 To: Milan Broz , Tejun Heo CC: Valdis.Kletnieks@vt.edu, Alexander Viro , Neil Brown , linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-raid@vger.kernel.org, device-mapper development Subject: Re: linux-next - WARNING: at fs/block_dev.c:824 bd_link_disk_holder+0x92/0x1ac() References: <16069.1294853673@localhost> <4D2E4611.90002@redhat.com> In-Reply-To: <4D2E4611.90002@redhat.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 01/13/11 09:23, Milan Broz wrote: > On 01/12/2011 06:34 PM, Valdis.Kletnieks@vt.edu wrote: >> Seen in a boot of yesterday's linux-next. The 'W' flag was due to the >> already-reported 'WARNING: at kernel/workqueue.c:1202 worker_enter_idle'. >> Not sure if it's a block_dev or dm/LVM issue, so I'm cc:'ing both groups. I wonder >> if the fact I still have 'CONFIG_DEVTMPFS=n' is involved (it's apparently ticking off >> dracut before and after the warning). >> >> [ 16.840333] dracut: Found volume group "vg_blackice" using metadata type lvm2 >> [ 16.892282] dracut: The link /dev/vg_blackice/opt should had been created by udev but it was not found. Falling back to direct link creation. >> [ 16.912627] ------------[ cut here ]------------ >> [ 16.912635] WARNING: at fs/block_dev.c:824 bd_link_disk_holder+0x92/0x1ac() > > That seems to be > WARN_ON_ONCE(!bdev->bd_holder || bdev->bd_holder_disk); > added in patch > http://git.kernel.org/?p=linux/kernel/git/next/linux-next.git;a=commitdiff;h=e09b457bdb7e8d23fc54dcef0930ac697d8de895 > "block: simplify holder symlink handling" > > dm linear just claims device in table constructor, I don't think it is bug in DM code. The patch assumes only one holder disk for a claimed dev, which is not true. E.g. if there are multiple LVs on a PV. In addition to that, since claiming is done in table constructor, there can be 2 claim instances for a slave/holder pair at a time when you load a table while there's already an active one. E.g. if you do lvresize. We need consideration for this, too. Thanks, -- Jun'ichi Nomura, NEC Corporation