From: Trond Myklebust <trond.myklebust@fys.uio.no>
Subject: Re: [PATCH] NFS: implement option checking when remounting NFS
	filesystems
Date: Fri, 11 Apr 2008 15:32:27 -0400
Message-ID: <1207942347.14621.1.camel@heimdal.trondhjem.org>
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	<47FFB9B3.1020703@redhat.com>
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Cc: linux-nfs@vger.kernel.org, nfsv4@linux-nfs.org,
	Jeff Layton <jlayton@redhat.com>
To: Peter Staubach <staubach@redhat.com>
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On Fri, 2008-04-11 at 15:19 -0400, Peter Staubach wrote:
> Jeff Layton wrote:
> > When remounting an NFS or NFS4 filesystem, the new NFS options are not
> > respected, yet the remount will still return success. This patch adds
> > a remount_fs sb op for NFS that checks any new nfs mount options against
> > the existing ones and fails the mount if any have changed.
> >
> > This is only implemented for string-based mount options since doing
> > this with binary options isn't really feasible.
> 
> What about respecting the new options as makes sense and rejecting
> those which absolutely can't be changed dynamically?

If we were to do this, then how should superblocks that are shared
between multiple mountpoints behave?

Cheers
  Trond