RE: [PATCH V2 03/10] hw/acpi: Add ACPI CPU hotplug init stub

[Salil Mehta]

> From: Jonathan Cameron <jonathan.cameron@huawei.com>
> Sent: Monday, October 2, 2023 5:01 PM
> To: Salil Mehta <salil.mehta@huawei.com>
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> Subject: Re: [PATCH V2 03/10] hw/acpi: Add ACPI CPU hotplug init stub
> 
> On Sat, 30 Sep 2023 01:19:26 +0100
> Salil Mehta <salil.mehta@huawei.com> wrote:
> 
> > ACPI CPU hotplug related initialization should only happen if
> ACPI_CPU_HOTPLUG
> > support has been enabled for particular architecture. Add
> cpu_hotplug_hw_init()
> > stub to avoid compilation break.
> >
> > Signed-off-by: Salil Mehta <salil.mehta@huawei.com>
> Seems reasonable.  For the other similar cases a stub isn't needed
> because GED is built when CONFIG_ACPI_HW_REDUCED=y and
> that select ACPI_MEMORY_HOTPLUG and ACPI_NVDIMM
> 
> You could do the same for the CPU hotplug case and instantiate
> a potentially useless memory region etc.  This seems more sensible to me
> 
> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>


Thanks
Salil.

> >  hw/acpi/acpi-cpu-hotplug-stub.c | 6 ++++++
> >  1 file changed, 6 insertions(+)
> >
> > diff --git a/hw/acpi/acpi-cpu-hotplug-stub.c b/hw/acpi/acpi-cpu-hotplug-
> stub.c
> > index 3fc4b14c26..c6c61bb9cd 100644
> > --- a/hw/acpi/acpi-cpu-hotplug-stub.c
> > +++ b/hw/acpi/acpi-cpu-hotplug-stub.c
> > @@ -19,6 +19,12 @@ void legacy_acpi_cpu_hotplug_init(MemoryRegion
> *parent, Object *owner,
> >      return;
> >  }
> >
> > +void cpu_hotplug_hw_init(MemoryRegion *as, Object *owner,
> > +                         CPUHotplugState *state, hwaddr base_addr)
> > +{
> > +    return;
> > +}
> > +
> >  void acpi_cpu_ospm_status(CPUHotplugState *cpu_st, ACPIOSTInfoList
> ***list)
> >  {
> >      return;