diff --git a/libc/kernel/uapi/linux/neighbour.h b/libc/kernel/uapi/linux/neighbour.h
index b5dcf2e..b86d2ae 100644
--- a/libc/kernel/uapi/linux/neighbour.h
+++ b/libc/kernel/uapi/linux/neighbour.h
@@ -108,6 +108,7 @@
   NDTPA_QUEUE_LENBYTES,
   NDTPA_MCAST_REPROBES,
   NDTPA_PAD,
+  NDTPA_INTERVAL_PROBE_TIME_MS,
   __NDTPA_MAX
 };
 #define NDTPA_MAX (__NDTPA_MAX - 1)