diff --git a/libc/kernel/common/linux/atmppp.h b/libc/kernel/common/linux/atmppp.h
index 3330c32..98e2e31 100644
--- a/libc/kernel/common/linux/atmppp.h
+++ b/libc/kernel/common/linux/atmppp.h
@@ -7,20 +7,25 @@
  ***   structures, and macros generated from the original header, and thus,
  ***   contains no copyrightable information.
  ***
+ ***   To edit the content of this header, modify the corresponding
+ ***   source file (e.g. under external/kernel-headers/original/) then
+ ***   run bionic/libc/kernel/tools/update_all.py
+ ***
+ ***   Any manual change here will be lost the next time this script will
+ ***   be run. You've been warned!
+ ***
  ****************************************************************************
  ****************************************************************************/
 #ifndef _LINUX_ATMPPP_H
 #define _LINUX_ATMPPP_H
-
 #include <linux/atm.h>
-
 #define PPPOATM_ENCAPS_AUTODETECT (0)
+/* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
 #define PPPOATM_ENCAPS_VC (1)
 #define PPPOATM_ENCAPS_LLC (2)
-
 struct atm_backend_ppp {
  atm_backend_t backend_num;
+/* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
  int encaps;
 };
-
 #endif