diff --git a/libc/kernel/common/linux/ktime.h b/libc/kernel/common/linux/ktime.h
index 34f8f0f..d3f167f 100644
--- a/libc/kernel/common/linux/ktime.h
+++ b/libc/kernel/common/linux/ktime.h
@@ -7,46 +7,53 @@
  ***   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_KTIME_H
 #define _LINUX_KTIME_H
-
 #include <linux/time.h>
 #include <linux/jiffies.h>
-
+/* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
 typedef union {
  s64 tv64;
 #if BITS_PER_LONG != (64 && !defined(CONFIG_KTIME_SCALAR))
  struct {
+/* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
 #ifdef __BIG_ENDIAN
  s32 sec, nsec;
 #else
  s32 nsec, sec;
+/* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
 #endif
  } tv;
 #endif
 } ktime_t;
-
+/* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
 #define KTIME_MAX ((s64)~((u64)1 << 63))
 #define KTIME_SEC_MAX (KTIME_MAX / NSEC_PER_SEC)
-
 #if BITS_PER_LONG == 64
-
 #if BITS_PER_LONG == 64
+/* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
 #endif
 #define ktime_sub(lhs, rhs)   ({ (ktime_t){ .tv64 = (lhs).tv64 - (rhs).tv64 }; })
 #define ktime_add(lhs, rhs)   ({ (ktime_t){ .tv64 = (lhs).tv64 + (rhs).tv64 }; })
 #define ktime_add_ns(kt, nsval)   ({ (ktime_t){ .tv64 = (kt).tv64 + (nsval) }; })
+/* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
 #define ktime_to_timespec(kt) ns_to_timespec((kt).tv64)
 #define ktime_to_timeval(kt) ns_to_timeval((kt).tv64)
 #define ktime_to_ns(kt) ((kt).tv64)
 #else
-
+/* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
 #endif
 #define KTIME_REALTIME_RES (ktime_t){ .tv64 = TICK_NSEC }
 #define KTIME_MONOTONIC_RES (ktime_t){ .tv64 = TICK_NSEC }
-
 #define ktime_get_real_ts(ts) getnstimeofday(ts)
-
+/* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
 #endif