[PATCHv3 03/14] cpu/hotplug: Add support for declaring CPU offlining not supported

[kirill.shutemov at linux.intel.com]

On Tue, Nov 21, 2023 at 02:15:59AM +0000, Huang, Kai wrote:
> On Wed, 2023-11-15 at 15:00 +0300, Kirill A. Shutemov wrote:
> > The ACPI MADT mailbox wakeup method doesn't allow to offline CPU after
> > it got woke up.
> > 
> > Currently offlining hotplug is prevented based on the confidential
> > computing attribute which is set for Intel TDX. But TDX is not
> > the only possible user of the wake up method. The MADT wakeup can be
> > implemented outside of a confidential computing environment. Offline
> > support is a property of the wakeup method, not the CoCo implementation.
> > 
> > Introduce cpu_hotplug_not_supported() that can be called to indicate
> > that CPU offlining should be disabled.
> 
> cpu_hotplug_not_supported() -> cpu_hotplug_disable_offlining().

Right.

> > 
> > This function is going to replace CC_ATTR_HOTPLUG_DISABLED for ACPI
> > MADT.
> 
> Is MADT too generic? MADT wakeup?

I'll replace it with "ACPI MADT wakeup method".

-- 
  Kiryl Shutsemau / Kirill A. Shutemov