[PATCH 08/12] KVM: SVM: Update AVIC settings when changing APIC mode

[Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>]

When APIC mode is updated (e.g. disabled, xAPIC, or x2APIC),
KVM needs to call kvm_vcpu_update_apicv() to update AVIC settings
accordingly.

Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
---
 arch/x86/kvm/svm/avic.c | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kvm/svm/avic.c b/arch/x86/kvm/svm/avic.c
index f378f7810db7..58b58a327826 100644
--- a/arch/x86/kvm/svm/avic.c
+++ b/arch/x86/kvm/svm/avic.c
@@ -620,7 +620,17 @@ void avic_post_state_restore(struct kvm_vcpu *vcpu)
 
 void svm_set_virtual_apic_mode(struct kvm_vcpu *vcpu)
 {
-	return;
+	struct vcpu_svm *svm = to_svm(vcpu);
+
+	if (!lapic_in_kernel(vcpu) || (avic_mode == AVIC_MODE_NONE))
+		return;
+
+	if (kvm_get_apic_mode(vcpu) == LAPIC_MODE_INVALID) {
+		WARN_ONCE(true, "Invalid local APIC state (vcpu_id=%d)", vcpu->vcpu_id);
+		return;
+	}
+
+	kvm_vcpu_update_apicv(&svm->vcpu);
 }
 
 void svm_hwapic_irr_update(struct kvm_vcpu *vcpu, int max_irr)
-- 
2.25.1