From:   Chuck Lever III <chuck.lever@oracle.com>
To:     Shachar Kagan <skagan@nvidia.com>
CC:     Jeff Layton <jlayton@kernel.org>,
        Ruben Vestergaard <rubenv@drcmr.dk>,
        Torkil Svensgaard <torkil@drcmr.dk>,
        Linux NFS Mailing List <linux-nfs@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] nfsd: don't free files unconditionally in
 __nfsd_file_cache_purge
Thread-Topic: [PATCH] nfsd: don't free files unconditionally in
 __nfsd_file_cache_purge
Thread-Index: AQHZLQi3y7Mea6cMiE2cfMbyen4b566nv26AgAAJSwCAAVH0gIAABJsAgAFqooCAAJHQAA==
Date:   Sun, 22 Jan 2023 23:40:25 +0000
Message-ID: <376AEBC5-AC52-424C-9DD0-A70BA73E7FE9@oracle.com>
References: <20230120195215.42243-1-jlayton@kernel.org>
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> On Jan 22, 2023, at 9:58 AM, Shachar Kagan <skagan@nvidia.com> wrote:
>=20
>=20
> On Sun, 2023-01-22 at 16:58 +0000, Shachar Kagan wrote:
>=20
>> On Sat, 2023-01-21 at 17:04 +0000, Chuck Lever III wrote:
>>>=20
>>>> On Jan 20, 2023, at 3:54 PM, Jeff Layton <jlayton@kernel.org> wrote:
>>>>=20
>>>> On Fri, 2023-01-20 at 20:21 +0000, Chuck Lever III wrote:
>>>>>=20
>>>>>> On Jan 20, 2023, at 2:52 PM, Jeff Layton <jlayton@kernel.org> wrote:
>>>>>>=20
>>>>>> nfsd_file_cache_purge is called when the server is shutting=20
>>>>>> down, in which case, tearing things down is generally fine, but=20
>>>>>> it also gets called when the exports cache is flushed.
>>>>>=20
>>>>> Yeah... cache flush is probably the case we've been missing.
>>>>>=20
>>>>>=20
>>>>>> Instead of walking the cache and freeing everything=20
>>>>>> unconditionally, handle it the same as when we have a notification o=
f conflicting access.
>>>>>>=20
>>>>>> Fixes: ac3a2585f018 ("nfsd: rework refcounting in filecache")
>>>>>> Reported-by: Ruben Vestergaard <rubenv@drcmr.dk>
>>>>>> Reported-by: Torkil Svensgaard <torkil@drcmr.dk>
>>>>>> Reported-by: Shachar Kagan <skagan@nvidia.com>
>>>>>> Signed-off-by: Jeff Layton <jlayton@kernel.org>
>=20
> I ran our tests with the commit, the issue didn't occur.
> Thanks for the quick response.

May I add Tested-by: Shachar Kagan <skagan@nvidia.com> ?

--
Chuck Lever