Re: [PATCH] drm/vkms: Fix bad matrix offset component multiplication

[Ariel D'Alessandro]

Hi Louis,

Sorry for the delay.

On 12/29/25 6:33 AM, Louis Chauvet wrote:
> On 12/23/25 18:26, Ariel D'Alessandro wrote:
> > Pixels values are packed as 16-bit UNORM values, so the matrix offset
> > components must be multiplied properly by the idempotent element -i.e.
> > number 1 encoded as 16-bit UNORM-.
> >
> > Signed-off-by: Ariel D'Alessandro <ariel.dalessandro@xxxxxxxxxxxxx>
>
> Hi,
>
> Thanks for this patch!
>
> How did you catch the issue? If you have an example of failing color 
> conversion, can you add a test case in vkms_color_test?
I found it while working on this IGT tools patch series [0], this patch 
in particular [1].

I've just added the related kunit test, so I'll send it as a v2 patchset.

[0] 
https://lore.kernel.org/igt-dev/20251223-post-blend-colorops-v2-0-f40aca9795bd@xxxxxxxxxxxxx/
[1] 
https://lore.kernel.org/igt-dev/20251223-post-blend-colorops-v2-7-f40aca9795bd@xxxxxxxxxxxxx/

Regards,

--
Ariel D'Alessandro
Software Engineer

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