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Date:   Wed, 11 Aug 2021 16:14:35 -0400
To:     Chuck Lever III <chuck.lever@oracle.com>
Cc:     Olga Kornievskaia <aglo@umich.edu>,
        Bruce Fields <bfields@redhat.com>,
        Timo Rothenpieler <timo@rothenpieler.org>,
        Linux NFS Mailing List <linux-nfs@vger.kernel.org>,
        Dai Ngo <dai.ngo@oracle.com>
Subject: Re: Spurious instability with NFSoRDMA under moderate load
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From:   bfields@fieldses.org (J. Bruce Fields)
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On Wed, Aug 11, 2021 at 08:01:30PM +0000, Chuck Lever III wrote:
> Probably not just CB_RECALL, but agreed, there doesn't seem to
> be any mechanism that can re-drive callback operations when the
> backchannel is replaced.

The nfsd4_queue_cb() in nfsd4_cb_release() should queue a work item
to run nfsd4_run_cb_work, which should set up another callback client if
necessary.

But I doubt this is well tested.

--b.