From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754568Ab0CWGls (ORCPT ); Tue, 23 Mar 2010 02:41:48 -0400 Received: from bohort.kerlabs.com ([62.160.40.57]:39307 "EHLO bohort.kerlabs.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754521Ab0CWGlr (ORCPT ); Tue, 23 Mar 2010 02:41:47 -0400 Date: Tue, 23 Mar 2010 07:41:41 +0100 From: Louis Rilling To: Matt Helsley Cc: "Serge E. Hallyn" , Linux Containers , lkml Subject: Re: [PATCH linux-cr] nested pid namespaces (v2) Message-ID: <20100323064140.GB4242@localdomain> Reply-To: Louis.Rilling@kerlabs.com References: <20100319213955.GA17912@us.ibm.com> <20100322105502.GB5569@localdomain> <20100322143800.GD3744@us.ibm.com> <20100322195735.GE20796@count0.beaverton.ibm.com> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="=_bohort-2221-1269326422-0001-2" Content-Disposition: inline In-Reply-To: <20100322195735.GE20796@count0.beaverton.ibm.com> User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This is a MIME-formatted message. If you see this text it means that your E-mail software does not support MIME-formatted messages. --=_bohort-2221-1269326422-0001-2 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Mon, Mar 22, 2010 at 12:57:35PM -0700, Matt Helsley wrote: > On Mon, Mar 22, 2010 at 09:38:00AM -0500, Serge E. Hallyn wrote: > > Quoting Louis Rilling (Louis.Rilling@kerlabs.com): > > > On Fri, Mar 19, 2010 at 04:39:55PM -0500, Serge E. Hallyn wrote: > > > > Support checkpoint and restart of tasks in nested pid namespaces. = At >=20 > >=20 > > > It would probably be safer too to use task_active_pid_ns() instead of > > > task->nsproxy->pid_ns, just in case some PID namespace unsharing like= proposed > > > by Eric makes it to mainline. > >=20 > > The task is frozen though so it shouldn't be able to unshare while being > > checkpointed, right? But it's probably better code anyway. >=20 > By the time it reaches checkpoint a frozen task is in the refrigerator > -- most often in the signal delivery portion of syscall return. So it can= 't > be making any new unshare/setns syscalls and any changes to the namespaces > should be visible. And what about a task having already unshared its pid namespace (from within the container)? In this case, all pid-related stuff should be based on task_active_pid_ns(), and ->nsproxy->pid_ns should be recorded too to corre= ctly restore pid unsharing. Thanks, Louis --=20 Dr Louis Rilling Kerlabs Skype: louis.rilling Batiment Germanium Phone: (+33|0) 6 80 89 08 23 80 avenue des Buttes de Coesmes http://www.kerlabs.com/ 35700 Rennes --=_bohort-2221-1269326422-0001-2 Content-Type: application/pgp-signature; name="signature.asc" Content-Transfer-Encoding: 7bit Content-Description: Digital signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.9 (GNU/Linux) iEYEARECAAYFAkuoYqQACgkQVKcRuvQ9Q1SzdgCguWeotr/sPeYkfOIQ/KGamduX ryMAoJMQsBelx+Av+SBB8hyTIVyKbqMa =LyF1 -----END PGP SIGNATURE----- --=_bohort-2221-1269326422-0001-2--