Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S967095Ab2ERTl6 (ORCPT ); Fri, 18 May 2012 15:41:58 -0400 Received: from 50-56-35-84.static.cloud-ips.com ([50.56.35.84]:47626 "EHLO mail.hallyn.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965529Ab2ERTl5 (ORCPT ); Fri, 18 May 2012 15:41:57 -0400 Date: Fri, 18 May 2012 19:44:17 +0000 From: "Serge E. Hallyn" To: Pavel Emelyanov Cc: "Eric W. Biederman" , Al Viro , Daniel Lezcano , Linux Kernel Mailing List , "Serge E. Hallyn" , Andrew Morton , "linux-fsdevel@vger.kernel.org" , Miklos Szeredi Subject: Re: [PATCH] vfs: Add setns support for the mount namespace Message-ID: <20120518194417.GA14195@mail.hallyn.com> References: <4FAD0524.3000307@parallels.com> <4FAD0555.4090906@parallels.com> <87mx5e5tho.fsf_-_@xmission.com> <4FAE4C70.5000804@parallels.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4FAE4C70.5000804@parallels.com> User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1810 Lines: 37 Quoting Pavel Emelyanov (xemul@parallels.com): > On 05/12/2012 12:54 AM, Eric W. Biederman wrote: > > > > setns support for the mount namespace is a little tricky as an arbitrary > > decision must be made about what to set fs->root and fs->pwd to, as > > there is no expectation of a relationship between the two mount > > namespaces. Therefore I arbitrarily find the root mount point, and > > follow every mount on top of it to find the top of the mount stack. > > Then I set fs->root and fs->pwd to that location. The topmost root of > > the mount stack seems like a reasonable place to be. > > > > Bind mount support for the mount namespace inodes has the possibility of > > creating circular dependencies between mount namespaces. Circular > > dependencies can result in loops that prevent mount namespaces from > > every being freed. I avoid creating those circular dependencies by > > adding a sequence number to the mount namespace and require all bind > > mounts be of a younger mount namespace into an older mount namespace. > > > > Add a helper function proc_ns_inode so it is possible to detect when we > > are attempting to bind mound a namespace inode. > > > > Signed-off-by: Eric W. Biederman > > Acked-by: Pavel Emelyanov These patches haven't made it into linux-next or Linus' tree. (More worrisome, is that the several online linux-kernel mail archives I've checked seem to have most of this thread, but not Eric's original patch.) What path were they expected to go in by? thanks, -serge -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/