[PATCH v3 6/6] RISC-V: Do not use cpumask data structure for hartid bitmap

[Atish Patra]

On Tue, Jan 25, 2022 at 12:12 PM Geert Uytterhoeven
<geert at linux-m68k.org> wrote:
>
> Hi Atish,
>
> On Thu, Jan 20, 2022 at 10:12 AM Atish Patra <atishp at rivosinc.com> wrote:
> > Currently, SBI APIs accept a hartmask that is generated from struct
> > cpumask. Cpumask data structure can hold upto NR_CPUs value. Thus, it
> > is not the correct data structure for hartids as it can be higher
> > than NR_CPUs for platforms with sparse or discontguous hartids.
> >
> > Remove all association between hartid mask and struct cpumask.
> >
> > Reviewed-by: Anup Patel <anup at brainfault.org> (For Linux RISC-V changes)
> > Acked-by: Anup Patel <anup at brainfault.org> (For KVM RISC-V changes)
> > Signed-off-by: Atish Patra <atishp at rivosinc.com>
>
> Thanks for your patch, which is now commit 26fb751ca37846c9 ("RISC-V:
> Do not use cpumask data structure for hartid bitmap") in v5.17-rc1.
>
> I am having an issue with random userspace SEGVs on Starlight Beta
> (which needs out-of-tree patches).  It doesn't always manifest
> itself immediately, so it took a while to bisect, but I suspect the
> above commit to be the culprit.
>

I have never seen one before during my testing. How frequently do you see them?
Does it happen while running anything or just idle user space results
in SEGVs randomly.

Do you have a trace that I can look into ?

> So far the Icicle looks unaffected.
>
> Do you have a clue?
> Thanks!
>
> Gr{oetje,eeting}s,
>
>                         Geert
>
> --
> Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert at linux-m68k.org
>
> In personal conversations with technical people, I call myself a hacker. But
> when I'm talking to journalists I just say "programmer" or something like that.
>                                 -- Linus Torvalds



-- 
Regards,
Atish