Index: head/sys/dev/hyperv/vmbus/hv_vmbus_drv_freebsd.c
===================================================================
--- head/sys/dev/hyperv/vmbus/hv_vmbus_drv_freebsd.c
+++ head/sys/dev/hyperv/vmbus/hv_vmbus_drv_freebsd.c
@@ -616,7 +616,7 @@
 	sizeof(struct vmbus_softc)
 };
 
-devclass_t vmbus_devclass;
+static devclass_t vmbus_devclass;
 
 DRIVER_MODULE(vmbus, acpi, vmbus_driver, vmbus_devclass, NULL, NULL);
 MODULE_DEPEND(vmbus, acpi, 1, 1, 1);