KVM: x86: fix vcpu initialization with userspace lapic
Moving the code around broke this rare configuration.
Use this opportunity to finally call lapic reset from vcpu reset.
Reported-by: syzbot+fb7a33a4b6c35007a72b@syzkaller.appspotmail.com
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Fixes: 0b2e9904c159 ("KVM: x86: move LAPIC initialization after VMCS creation")
Cc: stable@vger.kernel.org
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index cc5fe7a..391dda8 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -2002,14 +2002,13 @@
void kvm_lapic_reset(struct kvm_vcpu *vcpu, bool init_event)
{
- struct kvm_lapic *apic;
+ struct kvm_lapic *apic = vcpu->arch.apic;
int i;
- apic_debug("%s\n", __func__);
+ if (!apic)
+ return;
- ASSERT(vcpu);
- apic = vcpu->arch.apic;
- ASSERT(apic != NULL);
+ apic_debug("%s\n", __func__);
/* Stop the timer in case it's a reset to an active apic */
hrtimer_cancel(&apic->lapic_timer.timer);
@@ -2568,7 +2567,6 @@
pe = xchg(&apic->pending_events, 0);
if (test_bit(KVM_APIC_INIT, &pe)) {
- kvm_lapic_reset(vcpu, true);
kvm_vcpu_reset(vcpu, true);
if (kvm_vcpu_is_bsp(apic->vcpu))
vcpu->arch.mp_state = KVM_MP_STATE_RUNNABLE;
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 11649d2..18b5ca7 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -8060,7 +8060,6 @@
kvm_vcpu_mtrr_init(vcpu);
vcpu_load(vcpu);
kvm_vcpu_reset(vcpu, false);
- kvm_lapic_reset(vcpu, false);
kvm_mmu_setup(vcpu);
vcpu_put(vcpu);
return 0;
@@ -8103,6 +8102,8 @@
void kvm_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event)
{
+ kvm_lapic_reset(vcpu, init_event);
+
vcpu->arch.hflags = 0;
vcpu->arch.smi_pending = 0;