diff --git a/libc/kernel/uapi/linux/pr.h b/libc/kernel/uapi/linux/pr.h
index 7ce7390..7a7b8b1 100644
--- a/libc/kernel/uapi/linux/pr.h
+++ b/libc/kernel/uapi/linux/pr.h
@@ -18,6 +18,7 @@
  ****************************************************************************/
 #ifndef _UAPI_PR_H
 #define _UAPI_PR_H
+#include <linux/types.h>
 enum pr_type {
   PR_WRITE_EXCLUSIVE = 1,
   PR_EXCLUSIVE_ACCESS = 2,