KVM: nSVM: correctly inject INIT vmexits

The usual drill at this point, except there is no code to remove because this
case was not handled at all.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

arch/x86/kvm/svm/nested.c

@@ -25,6 +25,7 @@
 #include "trace.h"
 #include "mmu.h"
 #include "x86.h"
+#include "lapic.h"
 #include "svm.h"
 
 static void nested_svm_inject_npf_exit(struct kvm_vcpu *vcpu,
@@ -788,11 +789,37 @@ static void nested_svm_intr(struct vcpu_svm *svm)
 	nested_svm_vmexit(svm);
 }
 
+static inline bool nested_exit_on_init(struct vcpu_svm *svm)
+{
+	return (svm->nested.intercept & (1ULL << INTERCEPT_INIT));
+}
+
+static void nested_svm_init(struct vcpu_svm *svm)
+{
+	svm->vmcb->control.exit_code   = SVM_EXIT_INIT;
+	svm->vmcb->control.exit_info_1 = 0;
+	svm->vmcb->control.exit_info_2 = 0;
+
+	nested_svm_vmexit(svm);
+}
+
+
 static int svm_check_nested_events(struct kvm_vcpu *vcpu)
 {
 	struct vcpu_svm *svm = to_svm(vcpu);
 	bool block_nested_events =
 		kvm_event_needs_reinjection(vcpu) || svm->nested.nested_run_pending;
+	struct kvm_lapic *apic = vcpu->arch.apic;
+
+	if (lapic_in_kernel(vcpu) &&
+	    test_bit(KVM_APIC_INIT, &apic->pending_events)) {
+		if (block_nested_events)
+			return -EBUSY;
+		if (!nested_exit_on_init(svm))
+			return 0;
+		nested_svm_init(svm);
+		return 0;
+	}
 
 	if (vcpu->arch.exception.pending) {
 		if (block_nested_events)