From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751070AbWF1PCk (ORCPT ); Wed, 28 Jun 2006 11:02:40 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751291AbWF1PCk (ORCPT ); Wed, 28 Jun 2006 11:02:40 -0400 Received: from e4.ny.us.ibm.com ([32.97.182.144]:61876 "EHLO e4.ny.us.ibm.com") by vger.kernel.org with ESMTP id S1751070AbWF1PCj (ORCPT ); Wed, 28 Jun 2006 11:02:39 -0400 Date: Wed, 28 Jun 2006 10:01:42 -0500 From: "Serge E. Hallyn" To: Al Viro , Dave Hansen , akpm@osdl.org, linux-kernel@vger.kernel.org, serue@us.ibm.com Subject: Re: [PATCH 20/20] honor r/w changes at do_remount() time Message-ID: <20060628150142.GA17543@sergelap.austin.ibm.com> References: <20060627221436.77CCB048@localhost.localdomain> <20060627221457.04ADBF71@localhost.localdomain> <20060628051935.GA29920@ftp.linux.org.uk> <20060628144104.GE5572@MAIL.13thfloor.at> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20060628144104.GE5572@MAIL.13thfloor.at> User-Agent: Mutt/1.5.11 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Quoting Herbert Poetzl (herbert@13thfloor.at): > On Wed, Jun 28, 2006 at 06:19:35AM +0100, Al Viro wrote: > > On Tue, Jun 27, 2006 at 03:14:57PM -0700, Dave Hansen wrote: > > > > > > Originally from: Herbert Poetzl > > > > > > This is the core of the read-only bind mount patch set. > > > > > > Note that this does _not_ add a "ro" option directly to > > > the bind mount operation. If you require such a mount, > > > you must first do the bind, then follow it up with a > > > 'mount -o remount,ro' operation. > > > > I guess the fundamental problem I have with that approach is that it's > > a cop-out - we just declare rw state of vfsmount independent from that > > of filesystem and add a "if a flag is set, act upon vfsmount". > > IMHO the read only check has to be done twice, i.e > once for the superblock and a second time for the > particular vfs mount, similar, the procfs mounts > entry shows the combination (logical and) of the > write ability ... Shouldn't the vfsmount rw flag being set imply superblock rw? -serge