Re: [PATCH v2] efi: libstub: add support for the apple_set_os protocol

Ard Biesheuvel
2024-07-01T05:56:16Z

On Mon, 1 Jul 2024 at 07:50, Lukas Wunner <lukas@wunner.de> wrote:
>
> On Mon, Jul 01, 2024 at 07:38:38AM +0200, Ard Biesheuvel wrote:
> > Any thoughts on whether this should depend on CONFIG_APPLE_GMUX or not?
>
> I tend towards *not* making it depend on CONFIG_APPLE_GMUX:
>
> * The gpu-switch utility Orlando linked to doesn't use the apple-gmux
> driver. (It changes EFI variables that influence to which GPU the
> EFI driver will switch on next reboot.)
>
> * apple_set_os() has side effects beyond exposing the iGPU (such as
> switching the keyboard+trackpad access method to SPI instead of USB).
> If there are issues, they will be harder to debug if their occurrence
> depends on a Kconfig option.

Understood. I agree that having fewer possible combinations is
strongly preferred.

However, this change affects all Intel Macs. Is the latter side effect
likely to cause any regressions on Intel Mac users that don't have two
GPUs to begin with?