Re: More than 8 CPUs detected and CONFIG_X86_PC cannot handle it on 2.6.16-rc6

[Krzysztof Oledzki <olel@ans.pl>]

On Sun, 12 Mar 2006, Andrew Morton wrote:

> Krzysztof Oledzki <olel@ans.pl> wrote:
> > On Sat, 11 Mar 2006, Andrew Morton wrote:
> >
> > > Krzysztof Oledzki <olel@ans.pl> wrote:
> > >>
> > >> After upgrading to 2.6.16-rc6 I noticed this strange message:
> > >>
> > >>  More than 8 CPUs detected and CONFIG_X86_PC cannot handle it.
> > >>  Use CONFIG_X86_GENERICARCH or CONFIG_X86_BIGSMP.
> > >>
> > >> This is a Dell PowerEdge SC1425 with two P4 Xeons with HT enabled (so with
> > >>  totoal of 4 logical CPUs).
> > >
> > > Please send full dmesg output for the failing kernel, thanks.
> >  Attached.
> >
> > > Which is the most-recently-tested kernel which behaved correctly?
> >  2.6.15.6
>
> OK, thanks.  I assume the machine's working OK?

Yes. So far no problems, only this warning.

> From my reading, you have CONFIG_HOTPLUG_CPU enabled and the machine has an
> APIC.
That is correct.

> I'd expect that lots of people would hit that warning but for some
> reason they don't - possibly because most APICs don't have sufficiently
> high version numbers?
>
> Anyway, various people cc'ed.  I _think_ it's harmless, although the way in
> which def_to_bigsmp propagates into the DMI and APIC code might be a
> problem, depending upon config options.
>
> Certainly the warning is incorrect, but I'm not sure what is the best thing
> to do about it?

OK. Thank you.

Best regards,

				Krzysztof Olędzki