diff --git a/sys/modules/proto/Makefile b/sys/modules/proto/Makefile
index 4cfbd72a0bdf..3038c77f2f21 100644
--- a/sys/modules/proto/Makefile
+++ b/sys/modules/proto/Makefile
@@ -5,6 +5,7 @@
 KMOD=	proto
 SRCS=	\
 	proto_bus_pci.c \
+	proto_busdma.c \
 	proto_core.c
 
 SRCS+=	\