Re: [PATCH v2 1/2] efi/libstub: enable apple-set-os for all apple devices

Lukas Wunner
2026-01-29T10:33:03Z

On Thu, Jan 29, 2026 at 04:37:59AM +0000, Atharva Tiwari wrote:
> > As discussed previously, your patch will regress older MacBook Airs
> > which use SPI to access keyboard + trackpad if the set_os protocol
> > is invoked:
> >
> > https://lore.kernel.org/all/ZoJPgSlZJ3ZlU2zL@wunner.de/
> >
> > The last time this topic came up, I suggested counting the number of
> > GPUs instead of using the DMI quirk. I even provided a patch but
> > nobody with an eGPU bothered to test it, so the thread fizzled out:
> >
> > https://lore.kernel.org/all/Z6paeFrjdv7L3mtv@wunner.de/
> >
> > Maybe you could give it a spin and verify if it fixes the issue for you?
>
> I tested your patch, and well it works (you still need the 2nd patch to
> avoid a blank screen), but i can see how this will fail
> like for example, with the iMacPro (only has dGPU) you would need 2 eGPUs
> to turn on apple-set-os.

I don't quite follow. The patch counts the number of GPUs and
uses the set_os protocol if there are at least 2 of them.
One dGPU + one eGPU = 2, so the protocol is used.

Am I missing something?

Thanks,

Lukas