diff --git a/sys/netinet/tcp_subr.c b/sys/netinet/tcp_subr.c
--- a/sys/netinet/tcp_subr.c
+++ b/sys/netinet/tcp_subr.c
@@ -396,6 +396,7 @@
 	.tfb_tcp_output = tcp_default_output,
 	.tfb_tcp_do_segment = tcp_do_segment,
 	.tfb_tcp_ctloutput = tcp_default_ctloutput,
+	.tfb_tcp_timer_stop_all = tcp_timer_stop,
 	.tfb_tcp_handoff_ok = tcp_default_handoff_ok,
 	.tfb_tcp_fb_init = tcp_default_fb_init,
 	.tfb_tcp_fb_fini = tcp_default_fb_fini,
diff --git a/sys/netinet/tcp_timer.c b/sys/netinet/tcp_timer.c
--- a/sys/netinet/tcp_timer.c
+++ b/sys/netinet/tcp_timer.c
@@ -950,7 +950,7 @@
  * Until callout(9) is improved, just keep retrying.  In my profiling I've seen
  * such event happening less than 1 time per hour with 20-30 Gbit/s of traffic.
  */
-void
+int32_t
 tcp_timer_stop(struct tcpcb *tp)
 {
 	struct inpcb *inp = tptoinpcb(tp);
@@ -967,4 +967,5 @@
 		kern_yield(PRI_UNCHANGED);
 		INP_WLOCK(inp);
 	}
+	return (0);
 }
diff --git a/sys/netinet/tcp_var.h b/sys/netinet/tcp_var.h
--- a/sys/netinet/tcp_var.h
+++ b/sys/netinet/tcp_var.h
@@ -1456,7 +1456,7 @@
 void	 tcpip_fillheaders(struct inpcb *, uint16_t, void *, void *);
 void	 tcp_timer_activate(struct tcpcb *, tt_which, u_int);
 bool	 tcp_timer_active(struct tcpcb *, tt_which);
-void	 tcp_timer_stop(struct tcpcb *);
+int32_t	 tcp_timer_stop(struct tcpcb *);
 int	 inp_to_cpuid(struct inpcb *inp);
 /*
  * All tcp_hc_* functions are IPv4 and IPv6 (via in_conninfo)