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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 0/5] sunrpc: not refcounting svc_serv
Thread-Topic: [PATCH 0/5] sunrpc: not refcounting svc_serv
Thread-Index: AQHaCs5Bx30Sst3AQkeWzWCFyIpqgLBkCzaA
Date:   Tue, 31 Oct 2023 15:39:29 +0000
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References: <20231030011247.9794-1-neilb@suse.de>
In-Reply-To: <20231030011247.9794-1-neilb@suse.de>
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> On Oct 29, 2023, at 6:08 PM, NeilBrown <neilb@suse.de> wrote:
>=20
> This patch set continues earlier work of improving how threads and
> services are managed.  Specifically it drop the refcount.
>=20
> The refcount is always changed under the mutex, and almost always is
> exactly equal to the number of threads.  Those few cases where it is
> more than the number of threads can usefully be handled other ways as
> see in the patches.
>=20
> The first patches fixes a potential use-after-free when adding a socket
> fails.  This might be the UAF that Jeff mentioned recently.
>=20
> The second patch which removes the use of a refcount in pool_stats
> handling is more complex than I would have liked, but I think it is
> worth if for the result seen in 4/5 of substantial simplification.

So I need a v2 of this series, then...

 - Move 4/5 to the beginning of the series (patch 1 or 2, doesn't matter)

 - Add R-b, Fixes, and Cc: stable tags to those two patches

 - Address Jeff's other comments

AFAICT the 0-day bot reports were for the admin-revoked state series,
not this one.


--
Chuck Lever