Re: [GIT PULL] Kbuild updates for v6.15-rc1

From: Vlastimil Babka
Date: Mon Apr 07 2025 - 04:35:39 EST


On 4/6/25 18:50, Linus Torvalds wrote:
> On Sat, 5 Apr 2025 at 22:43, Damian Tometzki <damian@xxxxxxxxxxxxxx> wrote:
>>
>> i got the following error after this pull request.
>>
>> MODPOST Module.symvers
>> ERROR: modpost: missing MODULE_DESCRIPTION() in lib/tests/slub_kunit.o
>> make[3]: *** [/home/damian/kernel/linux/scripts/Makefile.modpost:147: Module.symvers] Error 1
>> make[2]: *** [/home/damian/kernel/linux/Makefile:1956: modpost] Error 2
>> make[1]: *** [/home/damian/kernel/linux/Makefile:248: __sub-make] Error 2
>> make[1]: Leaving directory '/home/damian/kernel/build'
>> make: *** [Makefile:248: __sub-make] Error 2
>
> I think I'll downgrade the error() to a warn() again, and make
> SLUB_TINY depend on !COMPILE_TEST.

Ack, thanks.

> And I'm not even convinced we should require module descriptions for
> silly test modules, but whatever.
>
> We'll see if something else pops up, but making the lack of a module
> description a fatal error was clearly not right as-is.
>
> Linus
>
> [*] In fact, I'm not convinced SLUB_TINYT ever makes sense at all, but
> that may be too unrelated to this to worry about.

Back when it was introduced, it allowed removing SLAB without breaking some
particular small systems, so I'd say it was worth it :) But since the
savings are mostly coming from not allocating for performance rather than
the disabled code size, we could probably easily turn it to a non-intrusive
boot option and not regress anyone.