pc: apic_common: Reset APIC ID to initial ID when switching into x2APIC mode

SDM: x2APIC State Transitions:
         State Changes From xAPIC Mode to x2APIC Mode
"
Any APIC ID value written to the memory-mapped
local APIC ID register is not preserved
"

Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Radim Krčmář <rkrcmar@redhat.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
This commit is contained in:
Igor Mammedov 2016-10-19 14:05:37 +02:00 committed by Eduardo Habkost
parent 4c34897aed
commit facb07cd2a

View file

@ -40,6 +40,11 @@ void cpu_set_apic_base(DeviceState *dev, uint64_t val)
if (dev) {
APICCommonState *s = APIC_COMMON(dev);
APICCommonClass *info = APIC_COMMON_GET_CLASS(s);
/* switching to x2APIC, reset possibly modified xAPIC ID */
if (!(s->apicbase & MSR_IA32_APICBASE_EXTD) &&
(val & MSR_IA32_APICBASE_EXTD)) {
s->id = s->initial_apic_id;
}
info->set_base(s, val);
}
}