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From:   "Benjamin Coddington" <bcodding@redhat.com>
To:     "Xuewei Zhang" <xueweiz@google.com>
Cc:     bfields@fieldses.org, "Grigor Avagyan" <grigora@google.com>,
        "Trevor Bourget" <bourget@google.com>,
        "Nauman Rafique" <nauman@google.com>,
        trond.myklebust@hammerspace.com, anna.schumaker@netapp.com,
        jlayton@kernel.org, linux-nfs@vger.kernel.org
Subject: Re: [PATCH] lockd: Show pid of lockd for remote locks
Date:   Sat, 18 May 2019 08:09:42 -0400
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On 17 May 2019, at 17:45, Xuewei Zhang wrote:
> Seems this patch introduced a bug in how lock protocol handles
> GRANTED_MSG in nfs.

Yes, you're right: it's broken, and broken badly because we find conflicting
locks based on lockd's fl_pid and lockd's fl_owner, which is current->files.
That means that clients are not differentiated, and that means that v3 locks
are broken.

I'd really like to see the fl_pid value make sense on the server when we
show it to userspace, so I think that we should stuff the svid in fl_owner.

Clearly I need to be more careful making changes here, so I am going to take
my time fixing this, and I won't get to it until Monday. A revert would get
us back to safe behavior.

Ben