KVM: VMX: Fix handling of a fault during NMI unblocked due to IRET
Bit 12 is undefined in any of the following cases:
If the VM exit sets the valid bit in the IDT-vectoring information field.
If the VM exit is due to a double fault.
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 7d7b0d6..631f9b7 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -3272,36 +3272,41 @@
static void vmx_complete_interrupts(struct vcpu_vmx *vmx)
{
u32 exit_intr_info;
- u32 idt_vectoring_info;
+ u32 idt_vectoring_info = vmx->idt_vectoring_info;
bool unblock_nmi;
u8 vector;
int type;
bool idtv_info_valid;
u32 error;
+ idtv_info_valid = idt_vectoring_info & VECTORING_INFO_VALID_MASK;
exit_intr_info = vmcs_read32(VM_EXIT_INTR_INFO);
if (cpu_has_virtual_nmis()) {
unblock_nmi = (exit_intr_info & INTR_INFO_UNBLOCK_NMI) != 0;
vector = exit_intr_info & INTR_INFO_VECTOR_MASK;
/*
- * SDM 3: 25.7.1.2
+ * SDM 3: 27.7.1.2 (September 2008)
* Re-set bit "block by NMI" before VM entry if vmexit caused by
* a guest IRET fault.
+ * SDM 3: 23.2.2 (September 2008)
+ * Bit 12 is undefined in any of the following cases:
+ * If the VM exit sets the valid bit in the IDT-vectoring
+ * information field.
+ * If the VM exit is due to a double fault.
*/
- if (unblock_nmi && vector != DF_VECTOR)
+ if ((exit_intr_info & INTR_INFO_VALID_MASK) && unblock_nmi &&
+ vector != DF_VECTOR && !idtv_info_valid)
vmcs_set_bits(GUEST_INTERRUPTIBILITY_INFO,
GUEST_INTR_STATE_NMI);
} else if (unlikely(vmx->soft_vnmi_blocked))
vmx->vnmi_blocked_time +=
ktime_to_ns(ktime_sub(ktime_get(), vmx->entry_time));
- idt_vectoring_info = vmx->idt_vectoring_info;
- idtv_info_valid = idt_vectoring_info & VECTORING_INFO_VALID_MASK;
vector = idt_vectoring_info & VECTORING_INFO_VECTOR_MASK;
type = idt_vectoring_info & VECTORING_INFO_TYPE_MASK;
if (vmx->vcpu.arch.nmi_injected) {
/*
- * SDM 3: 25.7.1.2
+ * SDM 3: 27.7.1.2 (September 2008)
* Clear bit "block by NMI" before VM entry if a NMI delivery
* faulted.
*/