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From:   David Howells <dhowells@redhat.com>
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To:     Alan Jenkins <alan.christopher.jenkins@gmail.com>
Cc:     dhowells@redhat.com, Al Viro <viro@ZenIV.linux.org.uk>,
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Subject: Re: [PATCH 31/34] vfs: syscall: Add fspick() to select a superblock for reconfiguration [ver #12]
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Date:   Wed, 17 Oct 2018 16:45:53 +0100
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Alan Jenkins <alan.christopher.jenkins@gmail.com> wrote:

> I agree.  I'm happy to see this is using the same check as do_remount().
> 
> 
> * change filesystem flags. dir should be a physical root of filesystem.
> * If you've mounted a non-root directory somewhere and want to do remount
> * on it - tough luck.
> */

Are you suggesting that it should only work at the ultimate root of a
superblock and not a bind mount somewhere within?

That's tricky to make work for NFS because s_root is a dummy dentry.

David