diff --git a/libc/kernel/uapi/linux/gtp.h b/libc/kernel/uapi/linux/gtp.h
index bd2fbcb..3b9416e 100644
--- a/libc/kernel/uapi/linux/gtp.h
+++ b/libc/kernel/uapi/linux/gtp.h
@@ -18,6 +18,7 @@
  ****************************************************************************/
 #ifndef _UAPI_LINUX_GTP_H_
 #define _UAPI_LINUX_GTP_H_
+#define GTP_GENL_MCGRP_NAME "gtp"
 enum gtp_genl_cmds {
   GTP_CMD_NEWPDP,
   GTP_CMD_DELPDP,