Re: [PATCH v1 1/1] libnvdimm: Don't use GUID APIs against raw buffer

From: Andy Shevchenko
Date: Fri Apr 16 2021 - 16:42:20 EST


On Fri, Apr 16, 2021 at 01:08:06PM -0700, Dan Williams wrote:
> [ add Erik ]
>
> On Fri, Apr 16, 2021 at 10:36 AM Andy Shevchenko
> <andriy.shevchenko@xxxxxxxxxxxxxxx> wrote:
> >
> > On Thu, Apr 15, 2021 at 05:37:54PM +0300, Andy Shevchenko wrote:
> > > Strictly speaking the comparison between guid_t and raw buffer
> > > is not correct. Return to plain memcmp() since the data structures
> > > haven't changed to use uuid_t / guid_t the current state of affairs
> > > is inconsistent. Either it should be changed altogether or left
> > > as is.
> >
> > Dan, please review this one as well. I think here you may agree with me.
>
> You know, this is all a problem because ACPICA is using a raw buffer.

And this is fine. It might be any other representation as well.

> Erik, would it be possible to use the guid_t type in ACPICA? That
> would allow NFIT to drop some ugly casts.

guid_t is internal kernel type. If we ever decide to deviate from the current
representation it wouldn't be possible in case a 3rd party is using it 1:1
(via typedef or so).

--
With Best Regards,
Andy Shevchenko