[PATCH 11/13] KVM: VMX: Use vmx_interrupt_blocked() directly from vmx_handle_exit()
From: Sean Christopherson
Date: Wed Apr 22 2020 - 22:26:04 EST
Use vmx_interrupt_blocked() instead of bouncing through
vmx_interrupt_allowed() when handling edge cases in vmx_handle_exit().
The nested_run_pending check in vmx_interrupt_allowed() should never
evaluate true in the VM-Exit path.
Hoist the WARN in handle_invalid_guest_state() up to vmx_handle_exit()
to enforce the above assumption for the !enable_vnmi case, and to detect
any other potential bugs with nested VM-Enter.
Signed-off-by: Sean Christopherson <sean.j.christopherson@xxxxxxxxx>
---
arch/x86/kvm/vmx/vmx.c | 19 ++++++++++---------
1 file changed, 10 insertions(+), 9 deletions(-)
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 50c726a21feb..2f8cacb3aa9b 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -5268,18 +5268,11 @@ static int handle_invalid_guest_state(struct kvm_vcpu *vcpu)
bool intr_window_requested;
unsigned count = 130;
- /*
- * We should never reach the point where we are emulating L2
- * due to invalid guest state as that means we incorrectly
- * allowed a nested VMEntry with an invalid vmcs12.
- */
- WARN_ON_ONCE(vmx->emulation_required && vmx->nested.nested_run_pending);
-
intr_window_requested = exec_controls_get(vmx) &
CPU_BASED_INTR_WINDOW_EXITING;
while (vmx->emulation_required && count-- != 0) {
- if (intr_window_requested && vmx_interrupt_allowed(vcpu))
+ if (intr_window_requested && !vmx_interrupt_blocked(vcpu))
return handle_interrupt_window(&vmx->vcpu);
if (kvm_test_request(KVM_REQ_EVENT, vcpu))
@@ -5896,6 +5889,14 @@ static int vmx_handle_exit(struct kvm_vcpu *vcpu,
if (enable_pml)
vmx_flush_pml_buffer(vcpu);
+ /*
+ * We should never reach this point with a pending nested VM-Enter, and
+ * more specifically emulation of L2 due to invalid guest state (see
+ * below) should never happen as that means we incorrectly allowed a
+ * nested VM-Enter with an invalid vmcs12.
+ */
+ WARN_ON_ONCE(vmx->nested.nested_run_pending);
+
/* If guest state is invalid, start emulating */
if (vmx->emulation_required)
return handle_invalid_guest_state(vcpu);
@@ -5962,7 +5963,7 @@ static int vmx_handle_exit(struct kvm_vcpu *vcpu,
if (unlikely(!enable_vnmi &&
vmx->loaded_vmcs->soft_vnmi_blocked)) {
- if (vmx_interrupt_allowed(vcpu)) {
+ if (!vmx_interrupt_blocked(vcpu)) {
vmx->loaded_vmcs->soft_vnmi_blocked = 0;
} else if (vmx->loaded_vmcs->vnmi_blocked_time > 1000000000LL &&
vcpu->arch.nmi_pending) {
--
2.26.0