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Subject[PATCH] kvm: x86: fix a race condition result to lost INIT
Date
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@zte.com.cn>
---
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

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