diff --git a/libc/kernel/uapi/linux/icmpv6.h b/libc/kernel/uapi/linux/icmpv6.h
index 9df18ad..a2ca922 100644
--- a/libc/kernel/uapi/linux/icmpv6.h
+++ b/libc/kernel/uapi/linux/icmpv6.h
@@ -81,6 +81,7 @@
 #define ICMPV6_MOBILE_PREFIX_SOL 146
 #define ICMPV6_MOBILE_PREFIX_ADV 147
 #define ICMPV6_MRDISC_ADV 151
+#define ICMPV6_MRDISC_SOL 152
 #define ICMPV6_MSG_MAX 255
 #define ICMPV6_NOROUTE 0
 #define ICMPV6_ADM_PROHIBITED 1