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From:   David Howells <dhowells@redhat.com>
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Subject: Re: [PATCH 3/7] vfs: Add a mount-notification facility
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Date:   Wed, 29 May 2019 00:08:37 +0100
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David Howells <dhowells@redhat.com> wrote:

> > It might make sense to redesign this stuff so that watches don't hold
> > references on the object being watched.
>
> I explicitly made it hold a reference so that if you place a watch on an
> automounted mount it stops it from expiring.
> 
> Further, if I create a watch on something, *should* it be unmountable, just as
> if I had a file open there or had chdir'd into there?

It gets trickier than that as I need a ref on the dentry on which the watch is
rooted to prevent it from getting culled.

David