diff --git a/libc/kernel/arch-x86/asm/mmu.h b/libc/kernel/arch-x86/asm/mmu.h
index 30db10a..61c3cc0 100644
--- a/libc/kernel/arch-x86/asm/mmu.h
+++ b/libc/kernel/arch-x86/asm/mmu.h
@@ -7,19 +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 _ASM_X86_MMU_H
 #define _ASM_X86_MMU_H
-
 #include <linux/spinlock.h>
 #include <linux/mutex.h>
-
+/* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
 typedef struct {
  void *ldt;
  int size;
  struct mutex lock;
+/* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
  void *vdso;
 } mm_context_t;
-
 #endif