Re: [PATCH net] selftests: drv-net: devmem: Skip when hugetlbfs isn't supported

[Maxime Chevallier]

On 10/23/26 19:52, Jakub Kicinski wrote:
> On Wed, 21 Oct 2026 11:08:51 +0200 Maxime Chevallier wrote:
>> The devmem selftest requires accessing /proc/sys/vm/nr_hugepages,
>> which is only available when hugetlbfs is supported. This isn't the
>> case on all CPU architectures, for example it isn't supported on ARM
>> 32-bits on cores that don't support LPAE.
>>
>> On these devices, the devmem kselftest doesn't skip gracefully
> 
> We don't require graceful skipping. If anything IMO hiding the stack
> traces isn't great.
> 
> If the check is extraneous and makes us fail some tests which don't
> actually require huge pages please make that clear in the commit
> message. Otherwise the net benefit of the changes is unclear.

hugetlbfs isn't required for devmem AFAICS, but the blamed commit
moved the access to nr_hugepages before the actual "is devmem
actually supported" test.

I don't expect the full test suite to gracefully run/skip for devmem
on these arm32 platforms TBH, it's likely that devmem is only something
that's been used on platforms that support hugetlbfs anyways, but
strictly speaking both features are unrelated.

Maxime