diff options
Diffstat (limited to 'arch/x86/kvm/lapic.c')
| -rw-r--r-- | arch/x86/kvm/lapic.c | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c index 191b5a962700..2183a9b8efa5 100644 --- a/arch/x86/kvm/lapic.c +++ b/arch/x86/kvm/lapic.c @@ -2078,7 +2078,12 @@ static void kvm_lapic_xapic_id_updated(struct kvm_lapic *apic) if (KVM_BUG_ON(apic_x2apic_mode(apic), kvm)) return; - if (kvm_xapic_id(apic) == apic->vcpu->vcpu_id) + /* + * Deliberately truncate the vCPU ID when detecting a modified APIC ID + * to avoid false positives if the vCPU ID, i.e. x2APIC ID, is a 32-bit + * value. + */ + if (kvm_xapic_id(apic) == (u8)apic->vcpu->vcpu_id) return; kvm_set_apicv_inhibit(apic->vcpu->kvm, APICV_INHIBIT_REASON_APIC_ID_MODIFIED); |