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-rw-r--r--arch/x86/kvm/vmx/nested.c32
-rw-r--r--arch/x86/kvm/vmx/vmcs.h5
2 files changed, 33 insertions, 4 deletions
diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c
index d1d867528698..838ac7ab5950 100644
--- a/arch/x86/kvm/vmx/nested.c
+++ b/arch/x86/kvm/vmx/nested.c
@@ -3695,12 +3695,34 @@ vmcs12_guest_cr4(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12)
}
static void vmcs12_save_pending_event(struct kvm_vcpu *vcpu,
- struct vmcs12 *vmcs12)
+ struct vmcs12 *vmcs12,
+ u32 vm_exit_reason, u32 exit_intr_info)
{
u32 idt_vectoring;
unsigned int nr;
- if (vcpu->arch.exception.injected) {
+ /*
+ * Per the SDM, VM-Exits due to double and triple faults are never
+ * considered to occur during event delivery, even if the double/triple
+ * fault is the result of an escalating vectoring issue.
+ *
+ * Note, the SDM qualifies the double fault behavior with "The original
+ * event results in a double-fault exception". It's unclear why the
+ * qualification exists since exits due to double fault can occur only
+ * while vectoring a different exception (injected events are never
+ * subject to interception), i.e. there's _always_ an original event.
+ *
+ * The SDM also uses NMI as a confusing example for the "original event
+ * causes the VM exit directly" clause. NMI isn't special in any way,
+ * the same rule applies to all events that cause an exit directly.
+ * NMI is an odd choice for the example because NMIs can only occur on
+ * instruction boundaries, i.e. they _can't_ occur during vectoring.
+ */
+ if ((u16)vm_exit_reason == EXIT_REASON_TRIPLE_FAULT ||
+ ((u16)vm_exit_reason == EXIT_REASON_EXCEPTION_NMI &&
+ is_double_fault(exit_intr_info))) {
+ vmcs12->idt_vectoring_info_field = 0;
+ } else if (vcpu->arch.exception.injected) {
nr = vcpu->arch.exception.nr;
idt_vectoring = nr | VECTORING_INFO_VALID_MASK;
@@ -3733,6 +3755,8 @@ static void vmcs12_save_pending_event(struct kvm_vcpu *vcpu,
idt_vectoring |= INTR_TYPE_EXT_INTR;
vmcs12->idt_vectoring_info_field = idt_vectoring;
+ } else {
+ vmcs12->idt_vectoring_info_field = 0;
}
}
@@ -4219,8 +4243,8 @@ static void prepare_vmcs12(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12,
* Transfer the event that L0 or L1 may wanted to inject into
* L2 to IDT_VECTORING_INFO_FIELD.
*/
- vmcs12->idt_vectoring_info_field = 0;
- vmcs12_save_pending_event(vcpu, vmcs12);
+ vmcs12_save_pending_event(vcpu, vmcs12,
+ vm_exit_reason, exit_intr_info);
vmcs12->vm_exit_intr_info = exit_intr_info;
vmcs12->vm_exit_instruction_len = vmcs_read32(VM_EXIT_INSTRUCTION_LEN);
diff --git a/arch/x86/kvm/vmx/vmcs.h b/arch/x86/kvm/vmx/vmcs.h
index e325c290a816..2b9d7a7e83f7 100644
--- a/arch/x86/kvm/vmx/vmcs.h
+++ b/arch/x86/kvm/vmx/vmcs.h
@@ -104,6 +104,11 @@ static inline bool is_breakpoint(u32 intr_info)
return is_exception_n(intr_info, BP_VECTOR);
}
+static inline bool is_double_fault(u32 intr_info)
+{
+ return is_exception_n(intr_info, DF_VECTOR);
+}
+
static inline bool is_page_fault(u32 intr_info)
{
return is_exception_n(intr_info, PF_VECTOR);