Re: [PATCH 3/6] M68K: cpuinfo: Fix a warning for CONFIG_CPUMASK_OFFSTACK

[Huacai Chen]

Hi, Geert,

On Tue, Jul 12, 2022 at 5:01 PM Geert Uytterhoeven <geert@xxxxxxxxxxxxxx> wrote:
>
> Hi Huacai,
>
> On Tue, Jul 12, 2022 at 10:53 AM Huacai Chen <chenhuacai@xxxxxxxxx> wrote:
> > On Tue, Jul 12, 2022 at 4:33 PM Geert Uytterhoeven <geert@xxxxxxxxxxxxxx> wrote:
> > > On Tue, Jul 12, 2022 at 9:53 AM Huacai Chen <chenhuacai@xxxxxxxxxxx> wrote:
> > > > When CONFIG_CPUMASK_OFFSTACK and CONFIG_DEBUG_PER_CPU_MAPS is selected,
> > >
> > > DEBUG_PER_CPU_MAPS depends on SMP, which is not supported on m68k,
> > > and thus cannot be enabled.
> > This patch is derived from MIPS and LoongArch, I search all
> > architectures and change those that look the same as MIPS and
> > LoongArch.
> > And the warning message below is also a copy-paste from LoongArch, sorry.
> >
> > Since M68K doesn't support SMP, then this patch seems to make no
> > difference, but does it make sense to keep consistency across all
> > architectures?
>
> Yes, having consistency is good.  But that should be mentioned in the
> patch description, instead of a scary warning CCed to stable ;-)
>
> BTW, you probably want to update the other copy of c_start() in
> arch/m68k/kernel/setup_mm.c, too.
For no-SMP architectures, it seems c_start() in
arch/m68k/kernel/setup_mm.c is more reasonable (just use 1, neither
NR_CPUS, nor nr_cpu_ids)?

Huacai
>
> Thanks!
>
> Gr{oetje,eeting}s,
>
>                         Geert
>
> --
> Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx
>
> 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