From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753703Ab1A0Iut (ORCPT ); Thu, 27 Jan 2011 03:50:49 -0500 Received: from smtp1-g21.free.fr ([212.27.42.1]:55870 "EHLO smtp1-g21.free.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752243Ab1A0Ius (ORCPT ); Thu, 27 Jan 2011 03:50:48 -0500 Message-ID: <4D4131DE.3080309@free.fr> Date: Thu, 27 Jan 2011 09:50:38 +0100 From: Daniel Lezcano User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.2.13) Gecko/20101208 Thunderbird/3.1.7 MIME-Version: 1.0 To: Andrew Morton CC: Li Zefan , containers@lists.linux-foundation.org, linux-kernel@vger.kernel.org, libvir-list@redhat.com Subject: Re: [PATCH] cgroup : remove the ns_cgroup References: <1295948388-15108-1-git-send-email-daniel.lezcano@free.fr> <20110126161837.43830756.akpm@linux-foundation.org> <4D40C5A3.4070703@cn.fujitsu.com> <20110126174513.c2a20fff.akpm@linux-foundation.org> In-Reply-To: <20110126174513.c2a20fff.akpm@linux-foundation.org> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 01/27/2011 02:45 AM, Andrew Morton wrote: > On Thu, 27 Jan 2011 09:08:51 +0800 Li Zefan wrote: > >> Andrew Morton wrote: >>> On Tue, 25 Jan 2011 10:39:48 +0100 >>> Daniel Lezcano wrote: >>> >>>> This patch removes the ns_cgroup as suggested in the following thread: >>> I had this patch queued up in September last year, but dropped it. Why >>> did I do that? >> Because you wanted to wait for some time for users (if any) to notice this >> coming change. >> >> Author: Daniel Lezcano >> Date: Wed Oct 27 15:33:38 2010 -0700 >> >> cgroup: notify ns_cgroup deprecated >> >> The ns_cgroup will be removed very soon. Let's warn, for this version, >> ns_cgroup is deprecated. >> >> Make ns_cgroup and clone_children exclusive. If the clone_children is set >> and the ns_cgroup is mounted, let's fail with EINVAL when the ns_cgroup >> subsys is created (a printk will help the user to understand why the >> creation fails). >> >> Update the feature remove schedule file with the deprecated ns_cgroup. >> >> Signed-off-by: Daniel Lezcano >> Acked-by: Paul Menage >> Signed-off-by: Andrew Morton >> Signed-off-by: Linus Torvalds > ooh, that was clever of me. > > Here is the text which was missing from the changelog: > > This is a userspace-visible change. Commit 45531757b45c ("cgroup: > notify ns_cgroup deprecated") (merged into 2.6.27) caused the kernel > to emit a printk warning users that the feature is planned for > removal. Since that time we have heard from XXX users who were > affected by this. > > Please provide XXX. Ok, AFAIK nobody makes use of the ns_cgroup except the LXC userspace tools which I maintain and where the backward compatibility with the ns_cgroup and the clone_children flag is already implemented. Since today nobody seems to be affected by this. I Cc'ed the libvirt mailing list. > How do we know that 2.6.37->2.6.38 is long enough? Will any major > distros be released containing this warning in that timeframe? I doubt > it. Hmm, maybe it is too short but I don't think someone will complain about this feature removal. Google chromium is using the namespaces, hence a lot of cgroup is created on the system. The vsftpd and some pam modules uses the namespaces too. I won't be surprised if one of these applications fails with 'clone' returning EEXIST ...