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Date:   Fri, 8 Nov 2019 12:51:09 -0500
From:   "J. Bruce Fields" <bfields@fieldses.org>
To:     "J. Bruce Fields" <bfields@redhat.com>
Cc:     Trond Myklebust <trondmy@hammerspace.com>,
        "linux-nfs@vger.kernel.org" <linux-nfs@vger.kernel.org>
Subject: Re: [PATCH v2] nfsd: Fix races between nfsd4_cb_release() and
 nfsd4_shutdown_callback()
Message-ID: <20191108175109.GA758@fieldses.org>
References: <20191023214318.9350-1-trond.myklebust@hammerspace.com>
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On Thu, Nov 07, 2019 at 05:27:12PM -0500, J. Bruce Fields wrote:
> On Tue, Oct 29, 2019 at 05:47:05PM -0400, J. Bruce Fields wrote:
> > On Fri, Oct 25, 2019 at 11:33:36AM -0400, bfields wrote:
> > > On Fri, Oct 25, 2019 at 11:21:19AM -0400, J. Bruce Fields wrote:
> > > > I thought I was running v2, let me double-check....
> > > 
> > > Yes, with v2 I'm getting a hang on generic/013.
> > > 
> > > I checked quickly and didn't see anything interesting in the logs,
> > > otherwise I haven't done any digging.
> > 
> > Reproduceable just with ./check -nfs generic/013.  The last thing I see
> > in wireshark is an asynchronous COPY call and reply.  Which means it's
> > probably trying to do a CB_OFFLOAD.  Hm.
> 
> Oh, I think it just needs the following.

Applying as follows, with part of the change split out into a separate
patch (since that's how I noticed the bug).

--b.