Re: [PATCH 1/2] drm: fix drm_vm for NOMMU builds

From: Benjamin Gaignard
Date: Wed Jan 11 2017 - 12:10:12 EST


2017-01-11 17:59 GMT+01:00 Arnd Bergmann <arnd@xxxxxxxx>:
> On Wed, Jan 11, 2017 at 5:36 PM, Daniel Vetter <daniel@xxxxxxxx> wrote:
>> On Wed, Jan 11, 2017 at 5:33 PM, Arnd Bergmann <arnd@xxxxxxxx> wrote:
>>> CONFIG_DRM_VM=y
>>
>> Does randconfig just set this for fun, despite that it's a hidden
>> Kconfig symbol? Should we add a depends !NOMMU to it to make sure it
>> never gets enabled when it shouldn't be?
>>
>> tbh I have no idea how Kconfig works, I'm just really good at breaking it :(
>
> no, randconfig won't try to set symbols that a user doesn't see. This
> is what 'menuconfig'
> says enabled it.
>
> â Selected by: DRM_NOUVEAU [=n] && HAS_IOMEM [=y] && DRM [=y] &&
> PCI [=n] && MMU [=n] && (BACKLIGHT_CLASS_DEVICE [=m] || !ACPI) ||
> DRM_LEGACY [=y] && HAS_IOMEM [=y] && DRM [=y]
>
> It must be the 'DRM_LEGACY' option that is actually user visible and
> that contains
> 'select DRM_VM'.

We should add "MMU" on DRM_LEGACY and DRM_VM dependencies
to be sure that they won't be select without MMU support

>
> Arnd



--
Benjamin Gaignard

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