1 files changed, 12 insertions, 0 deletions

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index f6449334ec45..ef432f891d30 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -5887,6 +5887,18 @@ static int inject_pending_event(struct kvm_vcpu *vcpu, bool req_int_win)
                         kvm_x86_ops->set_nmi(vcpu);
                 }
         } else if (kvm_cpu_has_injectable_intr(vcpu)) {
+                /*
+                 * Because interrupts can be injected asynchronously, we are
+                 * calling check_nested_events again here to avoid a race condition.
+                 * See https://lkml.org/lkml/2014/7/2/60 for discussion about this
+                 * proposal and current concerns.  Perhaps we should be setting
+                 * KVM_REQ_EVENT only on certain events and not unconditionally?
+                 */
+                if (is_guest_mode(vcpu) && kvm_x86_ops->check_nested_events) {
+                        r = kvm_x86_ops->check_nested_events(vcpu, req_int_win);
+                        if (r != 0)
+                                return r;
+                }
                 if (kvm_x86_ops->interrupt_allowed(vcpu)) {
                         kvm_queue_interrupt(vcpu, kvm_cpu_get_interrupt(vcpu),
                                             false);