On Tue, Feb 28, 2012 at 03:19:43PM +0800, Yong Zhang wrote:
> On Thu, Feb 23, 2012 at 12:58:05PM -0800, Paul E. McKenney wrote:
> > The acpi_processor_cst_has_changed() function is invoked from a
> > CPU_ONLINE or CPU_DEAD function, which might well execute on CPU 0
> > even though the CPU being hotplugged is some other CPU. In addition,
> > acpi_processor_cst_has_changed() invokes smp_processor_id() without
> > protection, resulting in splats when onlining CPUs.
> >
> > This commit therefore changes the smp_processor_id() to pr->id, as is
> > used elsewhere in the code, for example, in acpi_processor_add().
> >
> > This works for me, but I don't claim to understand ACPI.
> >
> > Signed-off-by: Paul E. McKenney <paul.mckenney@xxxxxxxxxx>
>
> Got the same warning.
> And the patch works on my side.
>
> Tested-by: Yong Zhang <yong.zhang0@xxxxxxxxx>
Thank you, I have added your Tested-by (and Srivatsa's Reviewed-by,
for that matter).
Any takers for this, or should I just push it up the -tip tree?
Thanx, Paul
> > diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c
> > index 0e8e2de..9e57b06 100644
> > --- a/drivers/acpi/processor_idle.c
> > +++ b/drivers/acpi/processor_idle.c
> > @@ -1159,8 +1159,7 @@ int acpi_processor_cst_has_changed(struct acpi_processor *pr)
> > * to make the code that updates C-States be called once.
> > */
> >
> > - if (smp_processor_id() == 0 &&
> > - cpuidle_get_driver() == &acpi_idle_driver) {
> > + if (pr->id == 0 && cpuidle_get_driver() == &acpi_idle_driver) {
> >
> > cpuidle_pause_and_lock();
> > /* Protect against cpu-hotplug */
> >
> > --
> > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> > the body of a message to majordomo@xxxxxxxxxxxxxxx
> > More majordomo info at http://vger.kernel.org/majordomo-info.html
> > Please read the FAQ at http://www.tux.org/lkml/
>
> --
> Only stand for myself
>
--
To unsubscribe from this list: send the line "unsubscribe linux-acpi" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
