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From:   Chuck Lever III <chuck.lever@oracle.com>
To:     Jeff Layton <jlayton@kernel.org>
CC:     Linux NFS Mailing List <linux-nfs@vger.kernel.org>
Subject: Re: [PATCH RFC] NFSD: Fix possible sleep during
 nfsd4_release_lockowner()
Thread-Topic: [PATCH RFC] NFSD: Fix possible sleep during
 nfsd4_release_lockowner()
Thread-Index: AQHYbfIMzaj7dJY/skSZB97V0kxLh60seYcAgAAWLQCAAAdIAIAABFwAgAAPm4CAAA1wgIAAA7CAgAAgnwA=
Date:   Mon, 23 May 2022 19:35:45 +0000
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> On May 23, 2022, at 1:38 PM, Jeff Layton <jlayton@kernel.org> wrote:
>=20
> On Mon, 2022-05-23 at 17:25 +0000, Chuck Lever III wrote:
>>=20
>>> On May 23, 2022, at 12:37 PM, Jeff Layton <jlayton@kernel.org> wrote:
>>>=20
>>> His suggestion was just to keep a counter in the lockowner of how many
>>> locks are associated with it. That seems like a good suggestion, though
>>> you'd probably need to add a parameter to lm_get_owner to indicate
>>> whether you were adding a new lock or just doing a conflock copy.
>>=20
>> locks_copy_conflock() would need to take a boolean parameter
>> that callers would set when they actually manipulate a lock.
>>=20
>=20
> Yep. You'd also have to add a bool arg to lm_put_owner so that you know
> whether you need to decrement the counter.

It's the lm_put_owner() side that looks less than straightforward.
Suggestions and advice welcome there.


--
Chuck Lever