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From:   Chuck Lever III <chuck.lever@oracle.com>
To:     Jeff Layton <jlayton@redhat.com>
CC:     Linux NFS Mailing List <linux-nfs@vger.kernel.org>
Subject: Re: [PATCH RFC] NFSD: Bump the ref count on nf_inode
Thread-Topic: [PATCH RFC] NFSD: Bump the ref count on nf_inode
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Date:   Thu, 7 Jul 2022 17:13:53 +0000
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> On Jul 7, 2022, at 1:12 PM, Jeff Layton <jlayton@redhat.com> wrote:
>=20
> On Thu, 2022-07-07 at 17:01 +0000, Chuck Lever III wrote:
>>=20
>>> On Jul 7, 2022, at 12:59 PM, Jeff Layton <jlayton@redhat.com> wrote:
>>>=20
>>> One other spot. We also dereference it in nfsd_file_mark_find_or_create=
,
>>> but I think that specific instance is OK. We know that we still hold a
>>> reference to the inode at that point since it comes from fhp->fh_dentry=
,
>>> so we shouldn't need to worry about it disappearing out from under us.
>>=20
>> Needs some annotation. I would prefer not to get that pointer from
>> nf_inode, then. As your comment says: compare only, never deref.
>>=20
>>=20
>=20
> Yeah, maybe we should pass in the inode as a separate parameter to that
> function?

That's what I ended up doing, that seems most clear.


--
Chuck Lever