[PATCH v2 18/22] KVM: nSVM: Preserve IRQ/NMI/SMI priority irrespective of exiting behavior

From: Paolo Bonzini
Date: Sat Apr 25 2020 - 03:02:49 EST


Short circuit vmx_check_nested_events() if an unblocked IRQ/NMI/SMI is
pending and needs to be injected into L2, priority between coincident
events is not dependent on exiting behavior.

Fixes: b518ba9fa691 ("KVM: nSVM: implement check_nested_events for interrupts")
Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
---
arch/x86/kvm/svm/nested.c | 12 +++++++++---
1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c
index a7a3d695405e..7c86ccb0e939 100644
--- a/arch/x86/kvm/svm/nested.c
+++ b/arch/x86/kvm/svm/nested.c
@@ -811,23 +811,29 @@ static int svm_check_nested_events(struct kvm_vcpu *vcpu)
kvm_event_needs_reinjection(vcpu) || svm->nested.exit_required ||
svm->nested.nested_run_pending;

- if (vcpu->arch.smi_pending && nested_exit_on_smi(svm)) {
+ if (vcpu->arch.smi_pending && !svm_smi_blocked(vcpu)) {
if (block_nested_events)
return -EBUSY;
+ if (!nested_exit_on_smi(svm))
+ return 0;
nested_svm_smi(svm);
return 0;
}

- if (vcpu->arch.nmi_pending && nested_exit_on_nmi(svm)) {
+ if (vcpu->arch.nmi_pending && !svm_nmi_blocked(vcpu)) {
if (block_nested_events)
return -EBUSY;
+ if (!nested_exit_on_nmi(svm))
+ return 0;
nested_svm_nmi(svm);
return 0;
}

- if (kvm_cpu_has_interrupt(vcpu) && nested_exit_on_intr(svm)) {
+ if (kvm_cpu_has_interrupt(vcpu) && !svm_interrupt_blocked(vcpu)) {
if (block_nested_events)
return -EBUSY;
+ if (!nested_exit_on_intr(svm))
+ return 0;
nested_svm_intr(svm);
return 0;
}
--
2.18.2