diff --git a/sys/compat/linux/linux_ioctl.c b/sys/compat/linux/linux_ioctl.c
index e63012f5a8a..1aa86d67bd4 100644
--- a/sys/compat/linux/linux_ioctl.c
+++ b/sys/compat/linux/linux_ioctl.c
@@ -33,6 +33,7 @@
 #include <sys/sysproto.h>
 #include <sys/cdio.h>
 #include <sys/dvdio.h>
+#include <sys/conf.h>
 #include <sys/disk.h>
 #include <sys/consio.h>
 #include <sys/ctype.h>