Index: head/sys/dev/hyperv/vmbus/vmbus.c
===================================================================
--- head/sys/dev/hyperv/vmbus/vmbus.c
+++ head/sys/dev/hyperv/vmbus/vmbus.c
@@ -315,6 +315,14 @@
 	return (vmbus_xact_wait(mh->mh_xact, &resp_len));
 }
 
+const struct vmbus_message *
+vmbus_msghc_poll_result(struct vmbus_softc *sc __unused, struct vmbus_msghc *mh)
+{
+	size_t resp_len;
+
+	return (vmbus_xact_poll(mh->mh_xact, &resp_len));
+}
+
 void
 vmbus_msghc_wakeup(struct vmbus_softc *sc, const struct vmbus_message *msg)
 {
Index: head/sys/dev/hyperv/vmbus/vmbus_var.h
===================================================================
--- head/sys/dev/hyperv/vmbus/vmbus_var.h
+++ head/sys/dev/hyperv/vmbus/vmbus_var.h
@@ -160,6 +160,9 @@
 const struct vmbus_message *
 		vmbus_msghc_wait_result(struct vmbus_softc *,
 		    struct vmbus_msghc *);
+const struct vmbus_message *
+		vmbus_msghc_poll_result(struct vmbus_softc *,
+		    struct vmbus_msghc *);
 void		vmbus_msghc_wakeup(struct vmbus_softc *,
 		    const struct vmbus_message *);
 void		vmbus_msghc_reset(struct vmbus_msghc *, size_t);