Re: [PATCH 3/3] drm/pl111: depend on CONFIG_VEXPRESS_CONFIG

[Rob Herring]

On Thu, Jun 3, 2021 at 1:42 PM Rob Herring <robh@xxxxxxxxxx> wrote:
>
> On Wed, Jun 2, 2021 at 4:53 PM Kees Cook <keescook@xxxxxxxxxxxx> wrote:
> >
> > Avoid randconfig build failures by requiring VEXPRESS_CONFIG:
> >
> > aarch64-linux-gnu-ld: drivers/gpu/drm/pl111/pl111_versatile.o: in function `pl111_vexpress_clcd_init':
> > pl111_versatile.c:(.text+0x220): undefined reference to `devm_regmap_init_vexpress_config'
>
> pl111_vexpress_clcd_init() starts with:
>
> if (!IS_ENABLED(CONFIG_VEXPRESS_CONFIG))
>                 return -ENODEV;
>
> Isn't that supposed to be enough to avoid an undefined reference?
>
> Making the whole file depend on VEXPRESS_CONFIG is not right either.
> Not all platforms need it.

Specifically, these defconfigs will break as they all use PL111 but
don't need nor enable VEXPRESS_CONFIG:

arch/arm/configs/integrator_defconfig:CONFIG_DRM_PL111=y
arch/arm/configs/lpc18xx_defconfig:CONFIG_DRM_PL111=y
arch/arm/configs/lpc32xx_defconfig:CONFIG_DRM_PL111=y
arch/arm/configs/nhk8815_defconfig:CONFIG_DRM_PL111=y
arch/arm/configs/realview_defconfig:CONFIG_DRM_PL111=y
arch/arm/configs/spear3xx_defconfig:CONFIG_DRM_PL111=y
arch/arm/configs/versatile_defconfig:CONFIG_DRM_PL111=y

These defconfigs should all be failing with the same error, but don't
from what I've tried nor have I seen any kernelci failures.

Rob