KVM: nSVM: correctly restore nested_run_pending on migration

The code to store it on the migration exists, but no code was restoring it.

One of the side effects of fixing this is that L1->L2 injected events
are no longer lost when migration happens with nested run pending.

Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Message-Id: <20210107093854.882483-3-mlevitsk@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Author: Maxim Levitsky

arch/x86/kvm/svm/nested.c

@@ -1194,6 +1194,10 @@ static int svm_set_nested_state(struct kvm_vcpu *vcpu,
 	 * in the registers, the save area of the nested state instead
 	 * contains saved L1 state.
 	 */
+
+	svm->nested.nested_run_pending =
+		!!(kvm_state->flags & KVM_STATE_NESTED_RUN_PENDING);
+
 	copy_vmcb_control_area(&hsave->control, &svm->vmcb->control);
 	hsave->save = *save;