diff --git a/sys/arm/arm/genassym.c b/sys/arm/arm/genassym.c
index beae19005bb3..8ddb05e54788 100644
--- a/sys/arm/arm/genassym.c
+++ b/sys/arm/arm/genassym.c
@@ -33,6 +33,7 @@ __FBSDID("$FreeBSD$");
 #include <sys/proc.h>
 #include <sys/mbuf.h>
 #include <sys/vmmeter.h>
+#include <sys/bus.h>
 #include <vm/vm.h>
 #include <vm/vm_param.h>
 #include <vm/pmap.h>