diff --git a/share/man/man4/tcp.4 b/share/man/man4/tcp.4
index 49fe2afaee95..b3139e74d4e1 100644
--- a/share/man/man4/tcp.4
+++ b/share/man/man4/tcp.4
@@ -34,7 +34,7 @@
 .\"     From: @(#)tcp.4	8.1 (Berkeley) 6/5/93
 .\" $FreeBSD$
 .\"
-.Dd October 21, 2016
+.Dd Jan 29, 2017
 .Dt TCP 4
 .Os
 .Sh NAME
@@ -586,6 +586,12 @@ downshift.
 List of available TCP function blocks (TCP stacks).
 .It Va functions_default
 The default TCP function block (TCP stack).
+.It Va functions_inherit_listen_socket_stack
+Determines whether to inherit listen socket's tcp stack or use the current
+system default tcp stack, as defined by
+.Va functions_default
+.Pc .
+Default is true.
 .It Va insecure_rst
 Use criteria defined in RFC793 instead of RFC5961 for accepting RST segments.
 Default is false.