Re: [PATCH 3/8] firmware: sysfb: Make CONFIG_SYSFB a user-selectable option

Arnd Bergmann
2026-04-02T13:09:28Z

On Thu, Apr 2, 2026, at 11:09, Thomas Zimmermann wrote:
> Add a descriptive string and help text to CONFIG_SYSFB, so that users
> can modify it. Flip all implicit selects in the Kconfig options into
> dependencies. This avoids cyclic dependencies in the config.
>
> Enabling CONFIG_SYSFB makes the kernel provide a device for the firmware
> framebuffer. As this can (slightly) affect system behavior, having a
> user-facing option seems preferable. Some users might also want to set
> every detail of their kernel config.
>
> Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>

I don't really like this part of the series and would prefer
to keep CONFIG_SYSFB hidden as much as possible as an x86
(and EFI) specific implementation detail, with the hope
of eventually seperating out the x86 bits from the EFI ones.

In general, I am always in favor of properly using Kconfig
dependencies over 'select' statements, for the same reasons
you describe, but I don't want the the x86 logic for
the legacy VESA and VGA console handling to leak into more
architectures than necessary.

Do you think we could instead move the sysfb_init()
function into the same two places that contain the
sysfb_primary_display definition (arch/x86/kernel/setup.c,
drivers/firmware/efi/efi-init.c) and simplify the efi version
to take out the x86 bits? That would reduce the rest
of sysfb-primary.c to the logic to unregister the device,
and that could then be selected by both x86 and EFI.

Arnd