From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757000Ab1ANHqE (ORCPT ); Fri, 14 Jan 2011 02:46:04 -0500 Received: from TYO201.gate.nec.co.jp ([202.32.8.193]:44101 "EHLO tyo201.gate.nec.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752697Ab1ANHp4 (ORCPT ); Fri, 14 Jan 2011 02:45:56 -0500 Message-ID: <4D2FFD5D.9070709@ce.jp.nec.com> Date: Fri, 14 Jan 2011 16:38:05 +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 , Kay Sievers , Tejun Heo CC: Karel Zak , device-mapper development , Valdis.Kletnieks@vt.edu, linux-kernel@vger.kernel.org, linux-raid@vger.kernel.org, Alexander Viro , linux-fsdevel@vger.kernel.org Subject: Re: [dm-devel] linux-next - WARNING: at fs/block_dev.c:824 bd_link_disk_holder+0x92/0x1ac() References: <16069.1294853673@localhost> <4D2E4611.90002@redhat.com> <4D2E6129.8000700@ce.jp.nec.com> <20110113110640.GC30719@htj.dyndns.org> <4D2EE156.1050006@redhat.com> <20110113122701.GG16523@nb.net.home> <20110113131216.GF30719@htj.dyndns.org> <20110113132637.GH16523@nb.net.home> <20110113133722.GG30719@htj.dyndns.org> <4D2F04FF.1070309@redhat.com> <20110113141107.GI30719@htj.dyndns.org> <4D2F0B6A.6010201@redhat.com> <4D2F1430.50906@redhat.com> In-Reply-To: <4D2F1430.50906@redhat.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 01/14/11 00:03, Milan Broz wrote: > On 01/13/2011 03:43 PM, Kay Sievers wrote: > >>> On Thu, Jan 13, 2011 at 3:25 PM, Milan Broz wrote: >>>> Maybe, but this was not invented in DM/MD camp:-) >>>> Probably Kay or Greg can answer why it was done this way? >> >> It's not from Greg or Kay. It just appeared some day in the context of dm. :) > > ah, then sorry, I am just confused:-) > But DM does not need it for operation at all so it must had some other reason. > (We have dmsetup ls --tree using dm-ioctls for years.) Sorry. It's from me 5 years ago. :) See this for backgrounds: [PATCH 0/3] sysfs representation of stacked devices (dm/md) http://lwn.net/Articles/172689/ And I don't adhere to my implementation if there's better one. Thanks, -- Jun'ichi Nomura, NEC Corporation