[PATCH v3 08/14] KVM: SVM: Update AVIC settings when changing APIC mode

From: Suravee Suthikulpanit
Date: Wed May 04 2022 - 03:33:22 EST


Update and refresh AVIC settings when guest APIC mode is updated
(e.g. changing between disabled, xAPIC, or x2APIC).

Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@xxxxxxx>
---
arch/x86/kvm/svm/avic.c | 16 ++++++++++++++++
arch/x86/kvm/svm/svm.c | 1 +
2 files changed, 17 insertions(+)

diff --git a/arch/x86/kvm/svm/avic.c b/arch/x86/kvm/svm/avic.c
index 3ebeea19b487..d185dd8ddf17 100644
--- a/arch/x86/kvm/svm/avic.c
+++ b/arch/x86/kvm/svm/avic.c
@@ -691,6 +691,22 @@ 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);
+ avic_refresh_apicv_exec_ctrl(&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 314628b6bff4..9066568fd19d 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -4692,6 +4692,7 @@ 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