Re: [git pull] drm for 6.15-rc1

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

On Tue, 01 Apr 2025, Jason Gunthorpe <jgg@nvidia.com> wrote:
> On Tue, Apr 01, 2025 at 10:42:35PM +0300, Jani Nikula wrote:
>> On Tue, 01 Apr 2025, Jason Gunthorpe <jgg@nvidia.com> wrote:
>> > So, I'd suggest a better way to run this is first build the kernel,
>> > then mine the gcc -MD output (ie stored in the .XX.cmd files) to
>> > generate a list of headers that are actually part of the build, then
>> > only test those. That eliminates all the kconfig problems. Opt out any
>> > special headers that really have a good reason not to be stand alone.
>> 
>> I think we'd want the drm headers pass the checks independent of configs
>> (apart from CONFIG_DRM). One size doesn't fit all.
>
> Why? That demand is just making it impossible to make shared
> infrastructure, and I don't think DRM should go off and build its own
> stuff just for DRM in a way that nobody else can use it.
>
> If you really, really, care then you can have your makefile codegen an
> "allheaders.c" that #includes drm/*.h and compile that.

The v2 series [1] generalizes the header checks and it's no longer in
any way dependent on DRM. For starters, each subsystem/driver needs to
decide for themselves which headers are to be checked. For DRM, it's
everything. Others can do as they please. And they can do so in their
Makefiles depending on configs too (actually drm/xe does this).

This can be expanded with more clever ways to choose the headers to
check. But we have to start *somewhere*.


BR,
Jani.


[1] https://lore.kernel.org/r/20250402124656.629226-1-jani.nikula@intel.com


-- 
Jani Nikula, Intel