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Subject: Re: [man-pages RFC PATCH v4] statx, inode: document the new
 STATX_INO_VERSION field
From:   Jeff Layton <jlayton@kernel.org>
To:     NeilBrown <neilb@suse.de>
Cc:     "J. Bruce Fields" <bfields@fieldses.org>,
        Theodore Ts'o <tytso@mit.edu>, Jan Kara <jack@suse.cz>,
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Date:   Mon, 12 Sep 2022 06:43:15 -0400
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On Sun, 2022-09-11 at 08:13 +1000, NeilBrown wrote:
> On Fri, 09 Sep 2022, Jeff Layton wrote:
> >=20
> > The machine crashes and comes back up, and we get a query for i_version
> > and it comes back as X. Fine, it's an old version. Now there is a write=
.
> > What do we do to ensure that the new value doesn't collide with X+1?=
=20
>=20
> (I missed this bit in my earlier reply..)
>=20
> How is it "Fine" to see an old version?
> The file could have changed without the version changing.
> And I thought one of the goals of the crash-count was to be able to
> provide a monotonic change id.
>=20

"Fine" in the sense that we expect that to happen in this situation.
It's not fine for the clients obviously, which is why we're discussing
mitigation techniques.
--=20
Jeff Layton <jlayton@kernel.org>