[PATCH v2 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 | 15 +++++++++++++++
 arch/x86/kvm/svm/svm.c  |  1 +
 2 files changed, 16 insertions(+)

diff --git a/arch/x86/kvm/svm/avic.c b/arch/x86/kvm/svm/avic.c
index 22ee1098e2a5..01392b8364f4 100644
--- a/arch/x86/kvm/svm/avic.c
+++ b/arch/x86/kvm/svm/avic.c
@@ -616,6 +616,21 @@ void avic_apicv_post_state_restore(struct kvm_vcpu *vcpu)
 	avic_handle_ldr_update(vcpu);
 }
 
+void avic_set_virtual_apic_mode(struct kvm_vcpu *vcpu)
+{
+	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);
+}
+
 static int avic_set_pi_irte_mode(struct kvm_vcpu *vcpu, bool activate)
 {
 	int ret = 0;
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index c85663b62d4e..b7dbd8bb2c0a 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -4606,6 +4606,7 @@ static struct kvm_x86_ops svm_x86_ops __initdata = {
 	.enable_nmi_window = svm_enable_nmi_window,
 	.enable_irq_window = svm_enable_irq_window,
 	.update_cr8_intercept = svm_update_cr8_intercept,
+	.set_virtual_apic_mode = avic_set_virtual_apic_mode,
 	.refresh_apicv_exec_ctrl = avic_refresh_apicv_exec_ctrl,
 	.check_apicv_inhibit_reasons = avic_check_apicv_inhibit_reasons,
 	.apicv_post_state_restore = avic_apicv_post_state_restore,
-- 
2.25.1