Re: [PATCH 3/4] kbuild: slim down package for building external modules

Jeffrey Hugo
2025-02-20T15:03:57Z

On 2/20/2025 3:03 AM, Nicolas Schier wrote:
> On Tue, Feb 18, 2025 at 01:25:38PM -0700, Jeffrey Hugo wrote:
>> On 7/27/2024 1:42 AM, Masahiro Yamada wrote:
>>> Exclude directories and files unnecessary for building external modules:
>>>
>>> - include/config/ (except include/config/auto.conf)
>>> - scripts/atomic/
>>> - scripts/dtc/
>>> - scripts/kconfig/
>>> - scripts/mod/mk_elfconfig
>>> - scripts/package/
>>> - scripts/unifdef
>>> - .config
>>
>> Please revert this (the removal of .config).
>>
>> I got some strange reports that our external module install broke, and
>> traced it to this change. Our external module references the .config
>> because we have different logic for the build depending on if other, related
>> modules are present or not.
>>
>> Also, it looks like this broke DKMS for some configurations, which not only
>> impacts DKMS itself [1] but also downstream projects [2].
>>
>> While DKMS may be updated going forward to avoid this issue, there are
>> plenty of affected version out in the wild.
>>
>> Also, I haven't surveyed every distro, but it looks like Ubuntu still
>> packages the .config with their headers in their upcoming "Plucky" release
>> based on 6.12. I suspect they wouldn't do that if they didn't feel it was
>> needed/useful.
>>
>> -Jeff
>>
>> [1]: https://github.com/dell/dkms/issues/464
>> [2]: https://github.com/linux-surface/linux-surface/issues/1654
>
> Hi Jeff,
>
> do you know the related thread [1]? According to the last mail, DKMS
> has fixed its issue already in December.

DKMS tip might be fixed, but production versions are in various distros,
which are not updated. Therefore actual users are impacted by this.

What happened to the #1 rule of kernel, that we do not break users?

This still needs to be reverted.

-Jeff

>
> Kind regards,
> Nicolas
>
> [1]: https://lore.kernel.org/linux-kbuild/CAK7LNARqEOVOzP5vdUVF0KxQBNb9xtYs-COSXXWDMpBzGaLGow@mail.gmail.com/T/#m95f48caf46357a41c1df5e038e227a01ab89dbda