KVM: x86: Consolidate APIC base RESET initialization code

Consolidate the APIC base RESET logic, which is currently spread out
across both x86 and vendor code.  For an in-kernel APIC, the vendor code
is redundant.  But for a userspace APIC, KVM relies on the vendor code
to initialize vcpu->arch.apic_base.  Hoist the vcpu->arch.apic_base
initialization above the !apic check so that it applies to both flavors
of APIC emulation, and delete the vendor code.
Reviewed-by: Reiji Watanabe <reijiw@google.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20210713163324.627647-19-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

arch/x86/kvm/lapic.c

@@ -2323,6 +2323,13 @@ void kvm_lapic_reset(struct kvm_vcpu *vcpu, bool init_event)
 	struct kvm_lapic *apic = vcpu->arch.apic;
 	int i;
 
+	if (!init_event) {
+		vcpu->arch.apic_base = APIC_DEFAULT_PHYS_BASE |
+				       MSR_IA32_APICBASE_ENABLE;
+		if (kvm_vcpu_is_reset_bsp(vcpu))
+			vcpu->arch.apic_base |= MSR_IA32_APICBASE_BSP;
+	}
+
 	if (!apic)
 		return;
 
@@ -2330,11 +2337,6 @@ void kvm_lapic_reset(struct kvm_vcpu *vcpu, bool init_event)
 	hrtimer_cancel(&apic->lapic_timer.timer);
 
 	if (!init_event) {
-		vcpu->arch.apic_base = APIC_DEFAULT_PHYS_BASE |
-				       MSR_IA32_APICBASE_ENABLE;
-		if (kvm_vcpu_is_reset_bsp(vcpu))
-			vcpu->arch.apic_base |= MSR_IA32_APICBASE_BSP;
-
 		apic->base_address = APIC_DEFAULT_PHYS_BASE;
 
 		kvm_apic_set_xapic_id(apic, vcpu->vcpu_id);

arch/x86/kvm/svm/svm.c

@@ -1336,12 +1336,6 @@ static void svm_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event)
 	svm->spec_ctrl = 0;
 	svm->virt_spec_ctrl = 0;
 
-	if (!init_event) {
-		vcpu->arch.apic_base = APIC_DEFAULT_PHYS_BASE |
-				       MSR_IA32_APICBASE_ENABLE;
-		if (kvm_vcpu_is_reset_bsp(vcpu))
-			vcpu->arch.apic_base |= MSR_IA32_APICBASE_BSP;
-	}
 	init_vmcb(vcpu);
 
 	/*

arch/x86/kvm/vmx/vmx.c

@@ -4407,13 +4407,6 @@ static void vmx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event)
 	vmx->hv_deadline_tsc = -1;
 	kvm_set_cr8(vcpu, 0);
 
-	if (!init_event) {
-		vcpu->arch.apic_base = APIC_DEFAULT_PHYS_BASE |
-				       MSR_IA32_APICBASE_ENABLE;
-		if (kvm_vcpu_is_reset_bsp(vcpu))
-			vcpu->arch.apic_base |= MSR_IA32_APICBASE_BSP;
-	}
-
 	vmx_segment_cache_clear(vmx);
 
 	seg_setup(VCPU_SREG_CS);