KVM: in-kernel LAPIC save and restore support
This patch adds a new vcpu-based IOCTL to save and restore the local
apic registers for a single vcpu. The kernel only copies the apic page as
a whole, extraction of registers is left to userspace side. On restore, the
APIC timer is restarted from the initial count, this introduces a little
delay, but works fine.
Signed-off-by: Yaozu (Eddie) Dong <eddie.dong@intel.com>
Signed-off-by: Qing He <qing.he@intel.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
diff --git a/drivers/kvm/lapic.c b/drivers/kvm/lapic.c
index 4b5c77d..df636bf 100644
--- a/drivers/kvm/lapic.c
+++ b/drivers/kvm/lapic.c
@@ -931,3 +931,16 @@
apic_clear_irr(vector, apic);
return vector;
}
+
+void kvm_apic_post_state_restore(struct kvm_vcpu *vcpu)
+{
+ struct kvm_lapic *apic = vcpu->apic;
+
+ apic->base_address = vcpu->apic_base &
+ MSR_IA32_APICBASE_BASE;
+ apic_set_reg(apic, APIC_LVR, APIC_VERSION);
+ apic_update_ppr(apic);
+ hrtimer_cancel(&apic->timer.dev);
+ update_divide_count(apic);
+ start_apic_timer(apic);
+}