KVM: x86: Fix APIC map calculation after re-enabling

commit e66d2ae7c67bd9ac982a3d1890564de7f7eabf4b upstream.

Update arch.apic_base before triggering recalculate_apic_map. Otherwise
the recalculation will work against the previous state of the APIC and
will fail to build the correct map when an APIC is hardware-enabled
again.

This fixes a regression of 1e08ec4a13.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index 0987c638db11fd843f714c6e017ad9be15509fdc..d0a97e8088284ec8380c2092f2244ad5a15cafda 100644 (file)
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -1364,6 +1364,10 @@ void kvm_lapic_set_base(struct kvm_vcpu *vcpu, u64 value)
                return;
        }
 
+       if (!kvm_vcpu_is_bsp(apic->vcpu))
+               value &= ~MSR_IA32_APICBASE_BSP;
+       vcpu->arch.apic_base = value;
+
        /* update jump label if enable bit changes */
        if ((vcpu->arch.apic_base ^ value) & MSR_IA32_APICBASE_ENABLE) {
                if (value & MSR_IA32_APICBASE_ENABLE)
@@ -1373,10 +1377,6 @@ void kvm_lapic_set_base(struct kvm_vcpu *vcpu, u64 value)
                recalculate_apic_map(vcpu->kvm);
        }
 
-       if (!kvm_vcpu_is_bsp(apic->vcpu))
-               value &= ~MSR_IA32_APICBASE_BSP;
-
-       vcpu->arch.apic_base = value;
        if ((old_value ^ value) & X2APIC_ENABLE) {
                if (value & X2APIC_ENABLE) {
                        u32 id = kvm_apic_id(apic);