From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2993035AbXDRTBM (ORCPT ); Wed, 18 Apr 2007 15:01:12 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S2993037AbXDRTBM (ORCPT ); Wed, 18 Apr 2007 15:01:12 -0400 Received: from pat.uio.no ([129.240.10.15]:58262 "EHLO pat.uio.no" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2993036AbXDRTBK (ORCPT ); Wed, 18 Apr 2007 15:01:10 -0400 Subject: Re: [Devel] Re: [patch 05/10] add "permit user mounts in new namespace" clone flag From: Trond Myklebust To: Christoph Hellwig Cc: Miklos Szeredi , ebiederm@xmission.com, serue@us.ibm.com, linuxram@us.ibm.com, linux-fsdevel@vger.kernel.org, viro@ftp.linux.org.uk, containers@lists.osdl.org, akpm@linux-foundation.org, linux-kernel@vger.kernel.org In-Reply-To: <20070418150110.GA29815@infradead.org> References: <20070416195652.GA350@sergelap.austin.ibm.com> <1176904505.6796.79.camel@heimdal.trondhjem.org> <1176906389.6796.96.camel@heimdal.trondhjem.org> <20070418150110.GA29815@infradead.org> Content-Type: text/plain Date: Wed, 18 Apr 2007 15:00:47 -0400 Message-Id: <1176922847.6796.127.camel@heimdal.trondhjem.org> Mime-Version: 1.0 X-Mailer: Evolution 2.10.1 Content-Transfer-Encoding: 7bit X-UiO-Resend: resent X-UiO-Spam-info: not spam, SpamAssassin (score=-0.1, required=12.0, autolearn=disabled, AWL=-0.060) X-UiO-Scanned: 7238BF512EC9E9EC63BCC5EB5D8C29D8E42FE73B X-UiO-SPAM-Test: remote_host: 129.240.10.9 spam_score: 0 maxlevel 200 minaction 2 bait 0 mail/h: 51 total 1168764 max/h 8345 blacklist 0 greylist 0 ratelimit 0 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 2007-04-18 at 16:01 +0100, Christoph Hellwig wrote: > I suspect the right answer here is to make nfs mount handling smarter. > The way mounting works the filesystem is allowed to choose whether it > can re-used a superblock or needs a new one. In the NFS case we probably > want to allow multiple superblocks for the same export if important > paramaters like the security model mismatch. It might also be another application for layering. If I were able to share enough of the inode and dentry information between superblocks, then all sorts of interesting possibilities arise... Cheers Trond