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Subject: Re: [PATCH -mm 5/7] add user namespace
From: Trond Myklebust <trond.myklebust@fys.uio.no>
To: "Eric W. Biederman" <ebiederm@xmission.com>
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Date: Sat, 15 Jul 2006 13:01:12 -0400
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On Sat, 2006-07-15 at 06:35 -0600, Eric W. Biederman wrote:
> I hope the confusion has passed for Trond.  My impression was he
> figured this was per process data so it didn't make sense any where
> near a filesystem, and the superblock was the last place it should
> be.

You are still using the wrong abstraction. Data that is not global to
the entire machine has absolutely _no_ place being put into the
superblock. It doesn't matter if it is process-specific,
container-specific or whatever-else-specific, it will still be vetoed.

If your real problem is uid/gid mapping on top of generic filesystems,
then have you looked into the *BSD solution of using a stackable
filesystem (i.e. umapfs)?

  Trond