diff --git a/sys/vm/vm_page.c b/sys/vm/vm_page.c
index 44b801eb287c..d778c992b9b4 100644
--- a/sys/vm/vm_page.c
+++ b/sys/vm/vm_page.c
@@ -100,6 +100,7 @@
 #include <sys/cdefs.h>
 __FBSDID("$FreeBSD$");
 
+#include "opt_msgbuf.h"
 #include "opt_vm.h"
 
 #include <sys/param.h>