KVM: VMX: Disallow NMI while blocked by STI

While not mandated by the spec, Linux relies on NMI being blocked by an
IF-enabling STI.  VMX also refuses to enter a guest in this state, at
least on some implementations.

Disallow NMI while blocked by STI by checking for the condition, and
requesting an interrupt window exit if it occurs.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
This commit is contained in:
Avi Kivity 2010-11-01 23:20:48 +02:00
parent 64f638c7c4
commit 30bd0c4c6c

View file

@ -2787,6 +2787,10 @@ static void enable_nmi_window(struct kvm_vcpu *vcpu)
return;
}
if (vmcs_read32(GUEST_INTERRUPTIBILITY_INFO) & GUEST_INTR_STATE_STI) {
enable_irq_window(vcpu);
return;
}
cpu_based_vm_exec_control = vmcs_read32(CPU_BASED_VM_EXEC_CONTROL);
cpu_based_vm_exec_control |= CPU_BASED_VIRTUAL_NMI_PENDING;
vmcs_write32(CPU_BASED_VM_EXEC_CONTROL, cpu_based_vm_exec_control);
@ -2849,7 +2853,8 @@ static int vmx_nmi_allowed(struct kvm_vcpu *vcpu)
return 0;
return !(vmcs_read32(GUEST_INTERRUPTIBILITY_INFO) &
(GUEST_INTR_STATE_MOV_SS | GUEST_INTR_STATE_NMI));
(GUEST_INTR_STATE_MOV_SS | GUEST_INTR_STATE_STI
| GUEST_INTR_STATE_NMI));
}
static bool vmx_get_nmi_mask(struct kvm_vcpu *vcpu)