-void kvm_set_apic_base(struct kvm_vcpu *vcpu, u64 data)
-{
- /* TODO: reserve bits check */
- kvm_lapic_set_base(vcpu, data);
+int kvm_set_apic_base(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
+{
+ u64 old_state = vcpu->arch.apic_base &
+ (MSR_IA32_APICBASE_ENABLE | X2APIC_ENABLE);
+ u64 new_state = msr_info->data &
+ (MSR_IA32_APICBASE_ENABLE | X2APIC_ENABLE);
+ u64 reserved_bits = ((~0ULL) << cpuid_maxphyaddr(vcpu)) |
+ 0x2ff | (guest_cpuid_has_x2apic(vcpu) ? 0 : X2APIC_ENABLE);
+
+ if (!msr_info->host_initiated &&
+ ((msr_info->data & reserved_bits) != 0 ||
+ new_state == X2APIC_ENABLE ||
+ (new_state == MSR_IA32_APICBASE_ENABLE &&
+ old_state == (MSR_IA32_APICBASE_ENABLE | X2APIC_ENABLE)) ||
+ (new_state == (MSR_IA32_APICBASE_ENABLE | X2APIC_ENABLE) &&
+ old_state == 0)))
+ return 1;
+
+ kvm_lapic_set_base(vcpu, msr_info->data);
+ return 0;