Re: [v2 PATCH 1/1] fs/proc: Expose mm_cpumask in /proc/[pid]/status

From: Aaron Tomlin

Date: Thu Jan 15 2026 - 13:40:59 EST


On Tue, Jan 06, 2026 at 07:54:54PM +0100, David Hildenbrand (Red Hat) wrote:
> Yes, starting with a very restrictive set, and carefully documenting it
> sounds good to me.

Hi David,

Acknowledged.

> One question is what would happen if these semantics one day change on x86.
> I guess best we can do is to ... document it very carefully.

Indeed.

> > I can document this arch-specific limitation in
> > Documentation/filesystems/proc.rst and wrapped the implementation in
> > CONFIG_X86 to avoid exposing "Best Effort" or zeroed-out data on
> > architectures where the mask is not meaningful.
> >
> > Please let me know your thoughts.
>
> Something along these lines. Maybe we want an CONFIG_ARCH_* define to unlock
> this from arch code.

That is a wonderful idea. I'll incorporate this suggestion within the next
iteration.


Kind regards,
--
Aaron Tomlin

Attachment: signature.asc
Description: PGP signature