Re: [Qemu-devel] [RFC 0/7+1] QEMU APIC ID + topology bug + CPU hotplug

[Gleb Natapov]

On Thu, Jul 12, 2012 at 03:51:48PM +0200, Igor Mammedov wrote:
> On 07/10/2012 10:22 PM, Eduardo Habkost wrote:
> >The hotplug case is a bit more complex: we need to either:
> >  - have a mechanism to let the ACPI SSDT code know what's the APIC ID of
> >    hotplugged CPUs; or
> >  - make Seabios run some code in the hotplugged CPU (I am assuming that 
> > this is
> >    simply not possible).
> If SMM is supported by qemu/kvm than it will be possible to trigger SMI from
> APCI method and SMI handler, that are supposed to run on all CPUs (including 
> hot-plugged one)
> , could fixup APIC ID of added CPU in some memory region used by ACPI.
> 
SMM is not supported (arguably is should not be supported on real HW
too), but even if it was default SMM address is 0x38000 IIRC and it is a
middle of a memory and can be used by a guest OS.

--
                        Gleb.