Re: [PATCH v1 1/1] tee: amdtee: Use %pUl printk() format specifier to print GUIDs

From: Andy Shevchenko
Date: Mon Sep 16 2024 - 05:38:20 EST


On Mon, Sep 16, 2024 at 01:38:27PM +0530, Rijo Thomas wrote:
> On 9/13/2024 2:59 PM, Andy Shevchenko wrote:
> > On Thu, Sep 12, 2024 at 07:50:08AM +0200, Jens Wiklander wrote:
> >> On Wed, Sep 11, 2024 at 10:41 PM Andy Shevchenko
> >> <andriy.shevchenko@xxxxxxxxxxxxxxx> wrote:
> >>>
> >>> Replace the custom approach with the %pUl printk() format specifier.
> >>> No functional change intended.
> >
> >> Thanks, the patch looks like a nice simplificatrion.
> >
> > Thank you for the review.
> >
> >> Rijo, Devaraj, does this work for you?
> >
> > Yes, please test, because seems others use uuid_t (UUID BE) for TEE,
> > but in this driver IIUC it's guid_t (UUID LE).
>
> No, this does not work for us. I tested this patch, it does not work as expected.
>
> %pUl gives output in uuid format (%08x-%04x-%04x-%02x%02x-%02x%02x%02x%02x%02x%02x).
> But, what we need, is a name with the format %08x-%04x-%04x-%02x%02x%02x%02x%02x%02x%02x%02x.
>
> Endian-ness is not an issue here. uuid generates name with 4 hypens (-).
> While, in our TA naming we are using 3 hyphens (-).

Ah, good catch! Can somebody add a comment there to explain that this uses
non-standard human-readable representation of GUID/UUID?

P.S. Thank you for testing!

--
With Best Regards,
Andy Shevchenko