diff --git a/libc/kernel/arch-arm/asm/poll.h b/libc/kernel/arch-arm/asm/poll.h
index c5b80a5..4c0f364 100644
--- a/libc/kernel/arch-arm/asm/poll.h
+++ b/libc/kernel/arch-arm/asm/poll.h
@@ -7,30 +7,38 @@
  ***   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 __ASMARM_POLL_H
 #define __ASMARM_POLL_H
-
 #define POLLIN 0x0001
 #define POLLPRI 0x0002
+/* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
 #define POLLOUT 0x0004
 #define POLLERR 0x0008
 #define POLLHUP 0x0010
 #define POLLNVAL 0x0020
-
+/* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
 #define POLLRDNORM 0x0040
 #define POLLRDBAND 0x0080
 #define POLLWRNORM 0x0100
 #define POLLWRBAND 0x0200
+/* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
 #define POLLMSG 0x0400
 #define POLLREMOVE 0x1000
 #define POLLRDHUP 0x2000
-
 struct pollfd {
+/* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
  int fd;
  short events;
  short revents;
 };
-
+/* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
 #endif