[PATCH 1/1] drm/amdkfd: Enable userptr support when KFD is enabled

[Felix Kuehling]

Am 2021-01-18 um 9:53 a.m. schrieb Christian König:
> Am 18.01.21 um 15:37 schrieb Felix Kuehling:
>> Am 2021-01-18 um 2:53 a.m. schrieb Christian König:
>>> Am 15.01.21 um 19:24 schrieb Felix Kuehling:
>>>> ROCm user mode depends on userptr support. Without it, KFD is
>>>> basically
>>>> useless.
>>>>
>>>> Signed-off-by: Felix Kuehling <Felix.Kuehling at amd.com>
>>>> ---
>>>>    drivers/gpu/drm/amd/amdkfd/Kconfig | 1 +
>>>>    1 file changed, 1 insertion(+)
>>>>
>>>> diff --git a/drivers/gpu/drm/amd/amdkfd/Kconfig
>>>> b/drivers/gpu/drm/amd/amdkfd/Kconfig
>>>> index e8fb10c41f16..2800b2bb2522 100644
>>>> --- a/drivers/gpu/drm/amd/amdkfd/Kconfig
>>>> +++ b/drivers/gpu/drm/amd/amdkfd/Kconfig
>>>> @@ -8,5 +8,6 @@ config HSA_AMD
>>>>        depends on DRM_AMDGPU && (X86_64 || ARM64 || PPC64)
>>>>        imply AMD_IOMMU_V2 if X86_64
>>>>        select MMU_NOTIFIER
>>>> +    select DRM_AMDGPU_USERPTR
>>> I think we should rather make that a depends on. Otherwise we select a
>>> visible config option.
>> I was considering that. The problem with that is, that the HSA_AMD
>> option won't even show up in menuconfig unless DRM_AMDGPU_USERPTR is
>> selected. I'd rather always show the HSA_AMD option and select what it
>> needs.
>>
>> Is there a good reason why AMDGPU_USERPTR is a "visible" config option?
>> What would be a reason for a user to deliberately disable this?
>
> The problem is the MMU notifier dependency, not everybody wants its.

Well, KFD already selects MMU_NOTIFIER. So selecting DRM_AMDGPU_USERPTR
won't do any more harm.

Regards,
  Felix


>
> I'm just not sure if it's legal to forcefully select a visible config
> option. E.g. what happens if an user unselects DRM_AMDGPU_USERPTR
> after it was selected here?
>
> Regards,
> Christian.
>
>>
>> Regards,
>>    Felix
>>
>>
>>> Christian.
>>>
>>>>        help
>>>>          Enable this if you want to use HSA features on AMD GPU
>>>> devices.
>