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From:   David Howells <dhowells@redhat.com>
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To:     Alan Jenkins <alan.christopher.jenkins@gmail.com>
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        torvalds@linux-foundation.org, ebiederm@xmission.com,
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Subject: Re: [PATCH 03/34] teach move_mount(2) to work with OPEN_TREE_CLONE [ver #12]
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Date:   Wed, 10 Oct 2018 12:56:30 +0100
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Alan Jenkins <alan.christopher.jenkins@gmail.com> wrote:

> I replied last time to wonder about the MNT_UMOUNT mnt_flag. So I've tested it
> now :-), on David's current tree (commit 5581f4935add).
> 
> The modified do_move_mount() allows re-attaching something that was
> lazy-unmounted. But the lazy unmount sets MNT_UMOUNT. And this flag is not
> cleared when the mount is re-attached.

Sorry, yes.  I'm not sure what the best way to deal with this is.  Should it
just return -EPERM or -ESTALE if MNT_UMOUNT is set?

David