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Date: Tue, 8 Oct 2013 18:11:35 +0200
From: Miklos Szeredi <miklos@szeredi.hu>
To: Andy Lutomirski <luto@amacapital.net>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>,
        "Serge E. Hallyn" <serge@hallyn.com>,
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        Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Rob Landley <rob@landley.net>,
        Linus Torvalds <torvalds@linux-foundation.org>
Subject: Re: [RFC][PATCH 4/3] vfs: Allow rmdir to remove mounts in all but
 the current mount namespace
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On Tue, Oct 08, 2013 at 09:06:29AM -0700, Andy Lutomirski wrote:

> > I think the risks of changing behavior outweigh the benefits.  How many
> > times did you have to remove or rename a mounted file or directory?  It's
> > very rarely needed.
> 
> I do this every time I reinstall a system while running that system.
> Admittedly, mount --move works, but that's a really unpleasant
> interface.
> 
> When rename2 gets added, there could be a flag RENAME_MOVE_MOUNT to opt in.

Good point.  Opting in would be the safest for both unlinkat() and
renameat2().

Thanks,
Miklos