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Date:   Fri, 28 Jan 2022 10:03:34 -0500
To:     Chuck Lever III <chuck.lever@oracle.com>
Cc:     Neil Brown <neilb@suse.de>,
        Linux NFS Mailing List <linux-nfs@vger.kernel.org>
Subject: Re: [RFC PATCH 0/4] nfsd: allow NFSv4 state to be revoked.
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From:   bfields@fieldses.org (J. Bruce Fields)
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On Fri, Jan 28, 2022 at 01:46:45PM +0000, Chuck Lever III wrote:
> My initial impulse is to better understand what is preventing
> the unexported filesystem from being unmounted. Better
> observability there could potentially be of value.

In theory that information's in /proc/fs/nfsd/clients/.  Somebody could
write a tool to scan that for state referencing a given filesystem.

--b.