Re: [PATCH] drm/xe: select CONFIGFS_FS dependency

[Jani Nikula <jani.nikula@linux.intel.com>]

On Fri, 02 Jan 2026, Riana Tauro <riana.tauro@intel.com> wrote:
> On 12/22/2025 6:12 PM, Jani Nikula wrote:
>> On Fri, 19 Dec 2025, Rodrigo Vivi <rodrigo.vivi@intel.com> wrote:
>>> On Fri, Dec 19, 2025 at 01:35:14PM +0530, Riana Tauro wrote:
>>>> Xe driver uses configfs functions to expose configuration to userspace.
>>>> If CONFIGFS_FS is built as module (=m) when Xe is built-in (=y),
>>>> undefined reference errors occur.
>>>
>>> Perhaps we don't need  this middle phrase. Only the first and the last.
>>> But anyway, we need the patch in. I just pushed it.
>> 
>> I think the correct fix to this one would've been
>> 
>> 	depends on CONFIGFS_FS || CONFIGFS_FS=n
>> 
>
> I tried this but it causes Kconfig recursive dependencies because some 
> configs select CONFIGFS_FS
>
> error: recursive dependency detected!
>          symbol DRM_XE depends on CONFIGFS_FS
>          symbol CONFIGFS_FS is selected by NET_9P_USBG
>          symbol NET_9P_USBG depends on USB_GADGET
>          symbol USB_GADGET is selected by USB_EHCI_TEGRA
>          symbol USB_EHCI_TEGRA depends on USB
>          symbol USB is selected by MOUSE_APPLETOUCH
>          symbol MOUSE_APPLETOUCH depends on INPUT
>          symbol INPUT is selected by DRM_XE

Yeah, it's the same old thing over and over and over and over again. A
symbol should really only be either selected or depended on, and only
non-visible symbols with no dependencies should be selected.

Documentation/kbuild/kconfig-language.rst:

  Note:
	select should be used with care. select will force
	a symbol to a value without visiting the dependencies.
	By abusing select you are able to select a symbol FOO even
	if FOO depends on BAR that is not set.
	In general use select only for non-visible symbols
	(no prompts anywhere) and for symbols with no dependencies.
	That will limit the usefulness but on the other hand avoid
	the illegal configurations all over.

DRM_XE also shouldn't select INPUT, and we have that because it's a hack
to work around other selects:

drivers/gpu/drm/xe/Kconfig:

	# xe depends on ACPI_VIDEO when ACPI is enabled
	# but for select to work, need to select ACPI_VIDEO's dependencies, ick

Then people work around the issues by throwing more selects around
everywhere, making the mess even harder to untangle.


BR,
Jani.


>
>
> Thanks
> Riana
>
>> BR,
>> Jani.
>> 
>>>
>>> Thanks,
>>> Rodrigo.
>>>
>>>> Add select CONFIGFS_FS to ensure configfs is built at minimum required
>>>> level.
>>>>
>>>> Cc: Matt Roper <matthew.d.roper@intel.com>
>>>> Reported-by: kernel test robot <lkp@intel.com>
>>>> Closes: https://lore.kernel.org/oe-kbuild-all/202512190827.IeXYj4qg-lkp@intel.com/
>>>> Closes: https://lore.kernel.org/oe-kbuild-all/202512181854.hPyTAXc5-lkp@intel.com/
>>>> Closes: https://lore.kernel.org/oe-kbuild-all/202512190407.CcUFXX2F-lkp@intel.com/
>>>> Fixes: 16280ded45fb ("drm/xe: Add configfs to enable survivability mode")
>>>> Signed-off-by: Riana Tauro <riana.tauro@intel.com>
>>>> ---
>>>>   drivers/gpu/drm/xe/Kconfig | 1 +
>>>>   1 file changed, 1 insertion(+)
>>>>
>>>> diff --git a/drivers/gpu/drm/xe/Kconfig b/drivers/gpu/drm/xe/Kconfig
>>>> index 4b288eb3f5b0..1094c5fc5bdf 100644
>>>> --- a/drivers/gpu/drm/xe/Kconfig
>>>> +++ b/drivers/gpu/drm/xe/Kconfig
>>>> @@ -46,6 +46,7 @@ config DRM_XE
>>>>   	select WANT_DEV_COREDUMP
>>>>   	select AUXILIARY_BUS
>>>>   	select REGMAP if I2C
>>>> +	select CONFIGFS_FS
>>>>   	help
>>>>   	  Driver for Intel Xe2 series GPUs and later. Experimental support
>>>>   	  for Xe series is also available.
>>>> -- 
>>>> 2.47.1
>>>>
>> 
>

-- 
Jani Nikula, Intel