Re: ACPI "_PDC" - acpi_processor_set_pdc()- execution regression - Linux-3.x

[Lin Ming <ming.m.lin@intel.com>]

On Thu, 2011-12-08 at 13:01 +0800, Bjorn Helgaas wrote:
> [+cc linux-acpi and Lin Ming]
> 
> On Wed, Dec 7, 2011 at 3:38 PM,  <wallak@free.fr> wrote:
> > We have a regression on the ACPI stack of the last linux kernel line 3.x (3.1.4,
> > 3.2-rc4...). The ACPI "_PDC" chunk is not executed on some computers (e.g. Dell
> > X300; the function acpi_processor_set_pdc() is not called). This issue yield to
> > an uninitialized state of some ACPI variables.
> >
> > A patch is available below. This patch come back to the previous linux behavior,
> > and works fine.

Hi, Wallak

Please attach the acpidump output and kernel .config file.
And also the output of "cat /proc/cpuinfo"

(You can send these files to me offline in case they are too big for
mail list)

Thanks,
Lin Ming

> >
> > Best Regards,
> > Wallak.
> >
> > --- linux-3.1.4-mdf/drivers/acpi/processor_core.c.orig  2011-12-07
> > 23:12:57.000000000 +0100
> > +++ linux-3.1.4-mdf/drivers/acpi/processor_core.c       2011-12-07
> > 23:13:39.000000000 +0100
> > @@ -223,8 +223,8 @@
> >        type = (acpi_type == ACPI_TYPE_DEVICE) ? 1 : 0;
> >        cpuid = acpi_get_cpuid(handle, type, acpi_id);
> >
> > -       if (cpuid == -1)
> > -               return false;
> > +       if ((cpuid == -1) && (num_possible_cpus() > 1))
> > +               return false;
> >
> >        return true;
> >  }
> > --
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