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From:   Chuck Lever III <chuck.lever@oracle.com>
To:     Neil Brown <neilb@suse.de>
CC:     Bruce Fields <bfields@fieldses.org>,
        Linux NFS Mailing List <linux-nfs@vger.kernel.org>
Subject: Re: [PATCH v1 1/5] SUNRPC: Fix the calculation of xdr->end in
 xdr_get_next_encode_buffer()
Thread-Topic: [PATCH v1 1/5] SUNRPC: Fix the calculation of xdr->end in
 xdr_get_next_encode_buffer()
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Date:   Tue, 7 Jun 2022 03:12:00 +0000
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> On Jun 6, 2022, at 10:35 PM, Chuck Lever III <chuck.lever@oracle.com> wro=
te:
>=20
>> On Jun 6, 2022, at 8:59 PM, NeilBrown <neilb@suse.de> wrote:
>> We then assign frag{1,2}bytes and have another chunk of code that looks
>> wrong to me.  I'd like
>>=20
>>  if (xdr->iov) {
>> 	xdr->iov->iov_len +=3D frag1bytes;
>> 	xdr->iov =3D NULL;
>>  } else {
>>       xdr->buf->page_len +=3D frag1bytes;
>>       xdr->page_ptr++;
>>  }
>>=20
>> Note that this changes the code NOT to increment pagE_ptr if iov was not
>> NULL.  I cannot see how it would be correct to do that.  Presumably this
>> code is never called with iov !=3D NULL ???
>=20
> That strikes me as a good change. I will add it to this series as
> another patch.
>=20
> Yes, this code is called by the server's READDIR encoder with iov =3D NUL=
L.
> See nfsd3_init_dirlist_pages().

This change breaks READDIR, looks like.

--
Chuck Lever