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From:   Chuck Lever III <chuck.lever@oracle.com>
To:     Dai Ngo <dai.ngo@oracle.com>
CC:     Chuck Lever <cel@kernel.org>, Jeff Layton <jlayton@kernel.org>,
        Linux NFS Mailing List <linux-nfs@vger.kernel.org>,
        "linux-fsdevel@vger.kernel.org" <linux-fsdevel@vger.kernel.org>
Subject: Re: [PATCH v5 2/3] NFSD: handle GETATTR conflict with write
 delegation
Thread-Topic: [PATCH v5 2/3] NFSD: handle GETATTR conflict with write
 delegation
Thread-Index: AQHZjQiHYb+9V1yj3kqcohFaOFOV+a9nJrQAgAA3oQCAAlg5gA==
Date:   Wed, 24 May 2023 17:51:15 +0000
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> On May 23, 2023, at 2:02 AM, Dai Ngo <dai.ngo@oracle.com> wrote:
>=20
>=20
> On 5/22/23 7:43 PM, Chuck Lever wrote:
>> On Mon, May 22, 2023 at 04:52:39PM -0700, Dai Ngo wrote:
>>> If the GETATTR request on a file that has write delegation in effect
>>> and the request attributes include the change info and size attribute
>>> then the write delegation is recalled and NFS4ERR_DELAY is returned
>>> for the GETATTR.
>> Isn't this yet another case where the server should send the
>> CB_RECALL and wait for it briefly, before resorting to
>> NFS4ERR_DELAY?
>=20
> Think about this more, I don't think we even need to recall the
> delegation at all. The Linux client does not flush the dirty file
> data before returning the delegation so the GETATTR still get stale
> attributes at the server. And the spec is not explicitly requires
> the delegation to be recalled.

I'm trying to get some feedback from other server implementers
about this. I'm willing to consider dropping this patch for now.


--
Chuck Lever