Re: [PATCH 10/23] afs: switch to use uuid_t and uuid_gen

From: Christoph Hellwig
Date: Thu May 25 2017 - 09:00:38 EST


On Tue, May 23, 2017 at 04:11:39PM +0300, Andy Shevchenko wrote:
> Since we introduced a union it's possible that we might access the
> member which wasn't last modified one. So, my comment is to give an
> attention on such possibility and avoid if there is an aliasing
> happened.

We do for AFS (and XFS for fs fsid). My preference would be to
not have the v1 struct defintion but instead provide a few
helpers in uuid.h that use get_unaligned_be* if needed:

uuid_v1_time_low()
uuid_v1_time_mid()
uuid_v1_time_time_hi_and_version()..

>From his previously reply it seems like Dave doesn't like that idea
too much, in which case I suspect moving struct uuid_v1 back into
afs and living with cast in it is the way to go.