kvm: x86: hyperv: Use APICv update request interface

Since disabling APICv has to be done for all vcpus on AMD-based
system, adopt the newly introduced kvm_request_apicv_update()
interface, and introduce a new APICV_INHIBIT_REASON_HYPERV.

Also, remove the kvm_vcpu_deactivate_apicv() since no longer used.

Cc: Roman Kagan <rkagan@virtuozzo.com>
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

arch/x86/include/asm/kvm_host.h

@@ -876,6 +876,7 @@ enum kvm_irqchip_mode {
 };
 
 #define APICV_INHIBIT_REASON_DISABLE    0
+#define APICV_INHIBIT_REASON_HYPERV     1
 
 struct kvm_arch {
 	unsigned long n_used_mmu_pages;
@@ -1483,7 +1484,6 @@ gpa_t kvm_mmu_gva_to_gpa_write(struct kvm_vcpu *vcpu, gva_t gva,
 gpa_t kvm_mmu_gva_to_gpa_system(struct kvm_vcpu *vcpu, gva_t gva,
 				struct x86_exception *exception);
 
-void kvm_vcpu_deactivate_apicv(struct kvm_vcpu *vcpu);
 bool kvm_apicv_activated(struct kvm *kvm);
 void kvm_apicv_init(struct kvm *kvm, bool enable);
 void kvm_vcpu_update_apicv(struct kvm_vcpu *vcpu);

arch/x86/kvm/hyperv.c

@@ -776,9 +776,10 @@ int kvm_hv_activate_synic(struct kvm_vcpu *vcpu, bool dont_zero_synic_pages)
 
 	/*
 	 * Hyper-V SynIC auto EOI SINT's are
-	 * not compatible with APICV, so deactivate APICV
+	 * not compatible with APICV, so request
+	 * to deactivate APICV permanently.
 	 */
-	kvm_vcpu_deactivate_apicv(vcpu);
+	kvm_request_apicv_update(vcpu->kvm, false, APICV_INHIBIT_REASON_HYPERV);
 	synic->active = true;
 	synic->dont_zero_synic_pages = dont_zero_synic_pages;
 	return 0;

arch/x86/kvm/svm.c

@@ -7318,7 +7318,8 @@ static bool svm_apic_init_signal_blocked(struct kvm_vcpu *vcpu)
 
 static bool svm_check_apicv_inhibit_reasons(ulong bit)
 {
-	ulong supported = BIT(APICV_INHIBIT_REASON_DISABLE);
+	ulong supported = BIT(APICV_INHIBIT_REASON_DISABLE) |
+			  BIT(APICV_INHIBIT_REASON_HYPERV);
 
 	return supported & BIT(bit);
 }

arch/x86/kvm/vmx/vmx.c

@@ -7712,7 +7712,8 @@ static __exit void hardware_unsetup(void)
 
 static bool vmx_check_apicv_inhibit_reasons(ulong bit)
 {
-	ulong supported = BIT(APICV_INHIBIT_REASON_DISABLE);
+	ulong supported = BIT(APICV_INHIBIT_REASON_DISABLE) |
+			  BIT(APICV_INHIBIT_REASON_HYPERV);
 
 	return supported & BIT(bit);
 }

arch/x86/kvm/x86.c

@@ -7457,19 +7457,6 @@ static void kvm_pv_kick_cpu_op(struct kvm *kvm, unsigned long flags, int apicid)
 	kvm_irq_delivery_to_apic(kvm, NULL, &lapic_irq, NULL);
 }
 
-void kvm_vcpu_deactivate_apicv(struct kvm_vcpu *vcpu)
-{
-	if (!lapic_in_kernel(vcpu)) {
-		WARN_ON_ONCE(vcpu->arch.apicv_active);
-		return;
-	}
-	if (!vcpu->arch.apicv_active)
-		return;
-
-	vcpu->arch.apicv_active = false;
-	kvm_x86_ops->refresh_apicv_exec_ctrl(vcpu);
-}
-
 bool kvm_apicv_activated(struct kvm *kvm)
 {
 	return (READ_ONCE(kvm->arch.apicv_inhibit_reasons) == 0);