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Subject: Re: [RFC PATCH 00/35] user xattr support (RFC8276)
From:   Chuck Lever <chucklever@gmail.com>
In-Reply-To: <20191104030132.GD26578@fieldses.org>
Date:   Mon, 4 Nov 2019 10:36:03 -0500
Cc:     Bruce Fields <bfields@fieldses.org>,
        Linux NFS Mailing List <linux-nfs@vger.kernel.org>,
        linux-fsdevel <linux-fsdevel@vger.kernel.org>
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To:     Frank van der Linden <fllinden@amazon.com>
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> On Nov 3, 2019, at 10:01 PM, bfields@fieldses.org wrote:
>=20
> On Fri, Oct 25, 2019 at 03:55:09PM -0400, Chuck Lever wrote:
>>> On Oct 24, 2019, at 7:15 PM, Frank van der Linden =
<fllinden@amazon.com> wrote:
>>> I think both of these are cases of being careful. E.g. don't enable
>>> something by default and allow it to be disabled at runtime in
>>> case something goes terribly wrong.
>>>=20
>>> I didn't have any other reasons, really. I'm happy do to away with
>>> the CONFIG options if that's the consensus, as well as the
>>> nouser_xattr export option.
>>=20
>> I have similar patches adding support for access to a couple of
>> security xattrs. I initially wrapped the new code with CONFIG
>> but after some discussion it was decided there was really no
>> need to be so cautious.
>>=20
>> The user_xattr export option is a separate matter, but again,
>> if we don't know of a use case for it, I would leave it out for
>> the moment.
>=20
> Agreed.
>=20
> Do ext4, xfs, etc. have an option to turn off xattrs?  If so, maybe it
> would be good enough to turn off xattrs on the exported filesystem
> rather than on the export.

Following the server's local file systems' mount options seems like a
good way to go. In particular, is there a need to expose user xattrs
on the server host, but prevent NFS clients' access to them? I can't
think of one.


> If not, maybe that's a sign that hasn't been a need.
>=20
> --b.

--
Chuck Lever
chucklever@gmail.com