diff --git a/include/linux/hyperv.h b/include/linux/hyperv.h
index 590fee6..b10954a 100644
--- a/include/linux/hyperv.h
+++ b/include/linux/hyperv.h
@@ -1120,7 +1120,7 @@
 			resource_size_t min, resource_size_t max,
 			resource_size_t size, resource_size_t align,
 			bool fb_overlap_ok);
-
+void vmbus_free_mmio(resource_size_t start, resource_size_t size);
 int vmbus_cpu_number_to_vp_number(int cpu_number);
 u64 hv_do_hypercall(u64 control, void *input, void *output);