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From:   Chuck Lever III <chuck.lever@oracle.com>
To:     Neil Brown <neilb@suse.de>
CC:     Jeff Layton <jlayton@kernel.org>,
        Linux NFS Mailing List <linux-nfs@vger.kernel.org>,
        Olga Kornievskaia <kolga@netapp.com>,
        Dai Ngo <dai.ngo@oracle.com>, Tom Talpey <tom@talpey.com>
Subject: Re: [PATCH] lockd: hold a reference to nlmsvc_serv while stopping
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Thread-Topic: [PATCH] lockd: hold a reference to nlmsvc_serv while stopping
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Date:   Tue, 10 Oct 2023 12:39:24 +0000
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> On Oct 9, 2023, at 7:35 PM, NeilBrown <neilb@suse.de> wrote:
> We are required to hold a reference to the svc_serv struct while
> stopping the last thread, as doing that could otherwise drop the last
> reference itself and the svc_serv would be freed while still in use.
>=20
> lockd doesn't do this.  After startup, the only reference is held by the
> running thread.
>=20
> So change locked to hold a reference on nlmsvc_serv while-ever the
> service is active, and only drop it after the last thread has been
> stopped.
>=20
> Note: it doesn't really make sense for threads to hold references to the
> svc_serv any more.  The fact threads are included in serv->sv_nrthreads
> is sufficient.  Maybe a future patch could address this.
>=20
> Reported-by: Jeff Layton <jlayton@kernel.org>
> Fixes: 68cc388c3238 ("SUNRPC: change how svc threads are asked to exit.")
> Signed-off-by: NeilBrown <neilb@suse.de>

Thanks for the fast response!

Should I squash this into 68cc, or apply it before? I would
like to ensure that bisect works nicely over this series of
commits.


--
Chuck Lever