[PATCH] kvm: x86: fix a race condition result to lost INIT

[Peng Hao]

when SMP VM start, AP may lost INIT because of receiving INIT between
kvm_vcpu_ioctl_x86_get/set_vcpu_events.

   vcpu 0                             vcpu 1
                               kvm_vcpu_ioctl_x86_get_vcpu_events
                                       events->smi.latched_init=0
 send INIT to vcpu1
   set vcpu1's pending_events
                               kvm_vcpu_ioctl_x86_set_vcpu_events
                                    events->smi.latched_init == 0
                                      clear INIT in pending_events
I don't think it need set/clear kernel state according to userspace's
info.

Signed-off-by: Peng Hao <peng.hao2@xxxxxxxxxx>
---
 arch/x86/kvm/x86.c | 6 ------
 1 file changed, 6 deletions(-)

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 6c7266f..393a7b7 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -3157,12 +3157,6 @@ static int kvm_vcpu_ioctl_x86_set_vcpu_events(struct kvm_vcpu *vcpu,
 			vcpu->arch.hflags |= HF_SMM_INSIDE_NMI_MASK;
 		else
 			vcpu->arch.hflags &= ~HF_SMM_INSIDE_NMI_MASK;
-		if (lapic_in_kernel(vcpu)) {
-			if (events->smi.latched_init)
-				set_bit(KVM_APIC_INIT, &vcpu->arch.apic->pending_events);
-			else
-				clear_bit(KVM_APIC_INIT, &vcpu->arch.apic->pending_events);
-		}
 	}
 
 	kvm_make_request(KVM_REQ_EVENT, vcpu);
-- 
1.8.3.1