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From:   "Benjamin Coddington" <bcodding@redhat.com>
To:     "Trond Myklebust" <trondmy@hammerspace.com>
Cc:     linux-nfs@vger.kernel.org, anna.schumaker@netapp.com
Subject: Re: [PATCH 1/2 v3] NFSv4: Fix a livelock when CLOSE pre-emptively
 bumps state sequence
Date:   Wed, 23 Sep 2020 15:46:45 -0400
Message-ID: <A38F09A7-34FC-483C-8629-51BA2D833DAD@redhat.com>
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On 23 Sep 2020, at 15:39, Trond Myklebust wrote:
> The client can't predict what is going to happen w.r.t. an OPEN call.
> If it does an open by name, it doesn't even know which file is going to
> get opened. That's why we have the wait loop
> in nfs_set_open_stateid_locked(). Why should we not do the same in
> CLOSE and OPEN_DOWNGRADE? It's the same problem.

I will give it a shot.  In the meantime, please consider adding this patch
which fixes a real bug today.  Thank you for your excellent advice and time.

Ben