Re: [PATCH] [RESEND] drm: fb_helper: fix CONFIG_FB dependency

[Kees Cook]

On Mon, Sep 27, 2021 at 04:28:02PM +0200, Arnd Bergmann wrote:
> From: Arnd Bergmann <arnd@xxxxxxxx>
> 
> With CONFIG_FB=m and CONFIG_DRM=y, we get a link error in the fb helper:
> 
> aarch64-linux-ld: drivers/gpu/drm/drm_fb_helper.o: in function `drm_fb_helper_alloc_fbi':
> (.text+0x10cc): undefined reference to `framebuffer_alloc'
> 
> Tighten the dependency so it is only allowed in the case that DRM can
> link against FB.
> 
> Fixes: f611b1e7624c ("drm: Avoid circular dependencies for CONFIG_FB")
> Link: https://lore.kernel.org/all/20210721152211.2706171-1-arnd@xxxxxxxxxx/
> Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>

Thanks for fixing this!

Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx>

-- 
Kees Cook