diff --git a/include/uapi/linux/mptcp.h b/include/uapi/linux/mptcp.h
index a6451561f3f8c..74cfe496891e0 100644
--- a/include/uapi/linux/mptcp.h
+++ b/include/uapi/linux/mptcp.h
@@ -57,6 +57,7 @@ struct mptcp_info {
 	__u64	mptcpi_bytes_sent;
 	__u64	mptcpi_bytes_received;
 	__u64	mptcpi_bytes_acked;
+	__u8	mptcpi_subflows_total;
 };
 
 /* MPTCP Reset reason codes, rfc8684 */
diff --git a/net/mptcp/pm_userspace.c b/net/mptcp/pm_userspace.c
index 5c01b9bc619a8..efecbe3cf4153 100644
--- a/net/mptcp/pm_userspace.c
+++ b/net/mptcp/pm_userspace.c
@@ -276,12 +276,12 @@ int mptcp_pm_nl_remove_doit(struct sk_buff *skb, struct genl_info *info)
 
 	if (!mptcp_pm_is_userspace(msk)) {
 		GENL_SET_ERR_MSG(info, "invalid request; userspace PM not selected");
-		goto remove_err;
+		goto out;
 	}
 
 	if (id_val == 0) {
 		err = mptcp_userspace_pm_remove_id_zero_address(msk, info);
-		goto remove_err;
+		goto out;
 	}
 
 	lock_sock(sk);
@@ -296,7 +296,7 @@ int mptcp_pm_nl_remove_doit(struct sk_buff *skb, struct genl_info *info)
 	if (!match) {
 		GENL_SET_ERR_MSG(info, "address with specified id not found");
 		release_sock(sk);
-		goto remove_err;
+		goto out;
 	}
 
 	list_move(&match->list, &free_list);
@@ -310,7 +310,7 @@ int mptcp_pm_nl_remove_doit(struct sk_buff *skb, struct genl_info *info)
 	}
 
 	err = 0;
- remove_err:
+out:
 	sock_put(sk);
 	return err;
 }
diff --git a/net/mptcp/protocol.h b/net/mptcp/protocol.h
index fe6f2d399ee89..458a2d7bb0ddc 100644
--- a/net/mptcp/protocol.h
+++ b/net/mptcp/protocol.h
@@ -1072,6 +1072,15 @@ static inline void __mptcp_do_fallback(struct mptcp_sock *msk)
 	set_bit(MPTCP_FALLBACK_DONE, &msk->flags);
 }
 
+static inline bool __mptcp_has_initial_subflow(const struct mptcp_sock *msk)
+{
+	struct sock *ssk = READ_ONCE(msk->first);
+
+	return ssk && ((1 << inet_sk_state_load(ssk)) &
+		       (TCPF_ESTABLISHED | TCPF_SYN_SENT |
+			TCPF_SYN_RECV | TCPF_LISTEN));
+}
+
 static inline void mptcp_do_fallback(struct sock *ssk)
 {
 	struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk);
diff --git a/net/mptcp/sockopt.c b/net/mptcp/sockopt.c
index 3536807337004..cabe856b2a45f 100644
--- a/net/mptcp/sockopt.c
+++ b/net/mptcp/sockopt.c
@@ -938,6 +938,8 @@ void mptcp_diag_fill_info(struct mptcp_sock *msk, struct mptcp_info *info)
 	info->mptcpi_bytes_sent = msk->bytes_sent;
 	info->mptcpi_bytes_received = msk->bytes_received;
 	info->mptcpi_bytes_retrans = msk->bytes_retrans;
+	info->mptcpi_subflows_total = info->mptcpi_subflows +
+		__mptcp_has_initial_subflow(msk);
 	unlock_sock_fast(sk, slow);
 }
 EXPORT_SYMBOL_GPL(mptcp_diag_fill_info);
diff --git a/tools/testing/selftests/net/mptcp/diag.sh b/tools/testing/selftests/net/mptcp/diag.sh
index 85a8ee9395b39..95b498efacd1f 100755
--- a/tools/testing/selftests/net/mptcp/diag.sh
+++ b/tools/testing/selftests/net/mptcp/diag.sh
@@ -182,23 +182,6 @@ chk_msk_inuse()
 	__chk_nr get_msk_inuse $expected "$msg" 0
 }
 
-# $1: ns, $2: port
-wait_local_port_listen()
-{
-	local listener_ns="${1}"
-	local port="${2}"
-
-	local port_hex i
-
-	port_hex="$(printf "%04X" "${port}")"
-	for i in $(seq 10); do
-		ip netns exec "${listener_ns}" cat /proc/net/tcp | \
-			awk "BEGIN {rc=1} {if (\$2 ~ /:${port_hex}\$/ && \$4 ~ /0A/) {rc=0; exit}} END {exit rc}" &&
-			break
-		sleep 0.1
-	done
-}
-
 wait_connected()
 {
 	local listener_ns="${1}"
@@ -222,7 +205,7 @@ echo "a" | \
 		ip netns exec $ns \
 			./mptcp_connect -p 10000 -l -t ${timeout_poll} -w 20 \
 				0.0.0.0 >/dev/null &
-wait_local_port_listen $ns 10000
+mptcp_lib_wait_local_port_listen $ns 10000
 chk_msk_nr 0 "no msk on netns creation"
 chk_msk_listen 10000
 
@@ -245,7 +228,7 @@ echo "a" | \
 		ip netns exec $ns \
 			./mptcp_connect -p 10001 -l -s TCP -t ${timeout_poll} -w 20 \
 				0.0.0.0 >/dev/null &
-wait_local_port_listen $ns 10001
+mptcp_lib_wait_local_port_listen $ns 10001
 echo "b" | \
 	timeout ${timeout_test} \
 		ip netns exec $ns \
@@ -266,7 +249,7 @@ for I in `seq 1 $NR_CLIENTS`; do
 				./mptcp_connect -p $((I+10001)) -l -w 20 \
 					-t ${timeout_poll} 0.0.0.0 >/dev/null &
 done
-wait_local_port_listen $ns $((NR_CLIENTS + 10001))
+mptcp_lib_wait_local_port_listen $ns $((NR_CLIENTS + 10001))
 
 for I in `seq 1 $NR_CLIENTS`; do
 	echo "b" | \
diff --git a/tools/testing/selftests/net/mptcp/mptcp_connect.sh b/tools/testing/selftests/net/mptcp/mptcp_connect.sh
index b1fc8afd072dc..7898d62fce0b5 100755
--- a/tools/testing/selftests/net/mptcp/mptcp_connect.sh
+++ b/tools/testing/selftests/net/mptcp/mptcp_connect.sh
@@ -254,31 +254,6 @@ else
 	set_ethtool_flags "$ns4" ns4eth3 "$ethtool_args"
 fi
 
-print_file_err()
-{
-	ls -l "$1" 1>&2
-	echo "Trailing bytes are: "
-	tail -c 27 "$1"
-}
-
-check_transfer()
-{
-	local in=$1
-	local out=$2
-	local what=$3
-
-	cmp "$in" "$out" > /dev/null 2>&1
-	if [ $? -ne 0 ] ;then
-		echo "[ FAIL ] $what does not match (in, out):"
-		print_file_err "$in"
-		print_file_err "$out"
-
-		return 1
-	fi
-
-	return 0
-}
-
 check_mptcp_disabled()
 {
 	local disabled_ns="ns_disabled-$rndh"
@@ -310,12 +285,6 @@ check_mptcp_disabled()
 	return 0
 }
 
-# $1: IP address
-is_v6()
-{
-	[ -z "${1##*:*}" ]
-}
-
 do_ping()
 {
 	local listener_ns="$1"
@@ -324,7 +293,7 @@ do_ping()
 	local ping_args="-q -c 1"
 	local rc=0
 
-	if is_v6 "${connect_addr}"; then
+	if mptcp_lib_is_v6 "${connect_addr}"; then
 		$ipv6 || return 0
 		ping_args="${ping_args} -6"
 	fi
@@ -341,38 +310,6 @@ do_ping()
 	return 0
 }
 
-# $1: ns, $2: MIB counter
-get_mib_counter()
-{
-	local listener_ns="${1}"
-	local mib="${2}"
-
-	# strip the header
-	ip netns exec "${listener_ns}" \
-		nstat -z -a "${mib}" | \
-			tail -n+2 | \
-			while read a count c rest; do
-				echo $count
-			done
-}
-
-# $1: ns, $2: port
-wait_local_port_listen()
-{
-	local listener_ns="${1}"
-	local port="${2}"
-
-	local port_hex i
-
-	port_hex="$(printf "%04X" "${port}")"
-	for i in $(seq 10); do
-		ip netns exec "${listener_ns}" cat /proc/net/tcp* | \
-			awk "BEGIN {rc=1} {if (\$2 ~ /:${port_hex}\$/ && \$4 ~ /0A/) {rc=0; exit}} END {exit rc}" &&
-			break
-		sleep 0.1
-	done
-}
-
 do_transfer()
 {
 	local listener_ns="$1"
@@ -441,12 +378,12 @@ do_transfer()
 			nstat -n
 	fi
 
-	local stat_synrx_last_l=$(get_mib_counter "${listener_ns}" "MPTcpExtMPCapableSYNRX")
-	local stat_ackrx_last_l=$(get_mib_counter "${listener_ns}" "MPTcpExtMPCapableACKRX")
-	local stat_cookietx_last=$(get_mib_counter "${listener_ns}" "TcpExtSyncookiesSent")
-	local stat_cookierx_last=$(get_mib_counter "${listener_ns}" "TcpExtSyncookiesRecv")
-	local stat_csum_err_s=$(get_mib_counter "${listener_ns}" "MPTcpExtDataCsumErr")
-	local stat_csum_err_c=$(get_mib_counter "${connector_ns}" "MPTcpExtDataCsumErr")
+	local stat_synrx_last_l=$(mptcp_lib_get_counter "${listener_ns}" "MPTcpExtMPCapableSYNRX")
+	local stat_ackrx_last_l=$(mptcp_lib_get_counter "${listener_ns}" "MPTcpExtMPCapableACKRX")
+	local stat_cookietx_last=$(mptcp_lib_get_counter "${listener_ns}" "TcpExtSyncookiesSent")
+	local stat_cookierx_last=$(mptcp_lib_get_counter "${listener_ns}" "TcpExtSyncookiesRecv")
+	local stat_csum_err_s=$(mptcp_lib_get_counter "${listener_ns}" "MPTcpExtDataCsumErr")
+	local stat_csum_err_c=$(mptcp_lib_get_counter "${connector_ns}" "MPTcpExtDataCsumErr")
 
 	timeout ${timeout_test} \
 		ip netns exec ${listener_ns} \
@@ -454,7 +391,7 @@ do_transfer()
 				$extra_args $local_addr < "$sin" > "$sout" &
 	local spid=$!
 
-	wait_local_port_listen "${listener_ns}" "${port}"
+	mptcp_lib_wait_local_port_listen "${listener_ns}" "${port}"
 
 	local start
 	start=$(date +%s%3N)
@@ -504,16 +441,16 @@ do_transfer()
 		return 1
 	fi
 
-	check_transfer $sin $cout "file received by client"
+	mptcp_lib_check_transfer $sin $cout "file received by client"
 	retc=$?
-	check_transfer $cin $sout "file received by server"
+	mptcp_lib_check_transfer $cin $sout "file received by server"
 	rets=$?
 
-	local stat_synrx_now_l=$(get_mib_counter "${listener_ns}" "MPTcpExtMPCapableSYNRX")
-	local stat_ackrx_now_l=$(get_mib_counter "${listener_ns}" "MPTcpExtMPCapableACKRX")
-	local stat_cookietx_now=$(get_mib_counter "${listener_ns}" "TcpExtSyncookiesSent")
-	local stat_cookierx_now=$(get_mib_counter "${listener_ns}" "TcpExtSyncookiesRecv")
-	local stat_ooo_now=$(get_mib_counter "${listener_ns}" "TcpExtTCPOFOQueue")
+	local stat_synrx_now_l=$(mptcp_lib_get_counter "${listener_ns}" "MPTcpExtMPCapableSYNRX")
+	local stat_ackrx_now_l=$(mptcp_lib_get_counter "${listener_ns}" "MPTcpExtMPCapableACKRX")
+	local stat_cookietx_now=$(mptcp_lib_get_counter "${listener_ns}" "TcpExtSyncookiesSent")
+	local stat_cookierx_now=$(mptcp_lib_get_counter "${listener_ns}" "TcpExtSyncookiesRecv")
+	local stat_ooo_now=$(mptcp_lib_get_counter "${listener_ns}" "TcpExtTCPOFOQueue")
 
 	expect_synrx=$((stat_synrx_last_l))
 	expect_ackrx=$((stat_ackrx_last_l))
@@ -542,8 +479,8 @@ do_transfer()
 	fi
 
 	if $checksum; then
-		local csum_err_s=$(get_mib_counter "${listener_ns}" "MPTcpExtDataCsumErr")
-		local csum_err_c=$(get_mib_counter "${connector_ns}" "MPTcpExtDataCsumErr")
+		local csum_err_s=$(mptcp_lib_get_counter "${listener_ns}" "MPTcpExtDataCsumErr")
+		local csum_err_c=$(mptcp_lib_get_counter "${connector_ns}" "MPTcpExtDataCsumErr")
 
 		local csum_err_s_nr=$((csum_err_s - stat_csum_err_s))
 		if [ $csum_err_s_nr -gt 0 ]; then
@@ -613,9 +550,8 @@ make_file()
 	ksize=$((SIZE / 1024))
 	rem=$((SIZE - (ksize * 1024)))
 
-	dd if=/dev/urandom of="$name" bs=1024 count=$ksize 2> /dev/null
-	dd if=/dev/urandom conv=notrunc of="$name" bs=1 count=$rem 2> /dev/null
-	echo -e "\nMPTCP_TEST_FILE_END_MARKER" >> "$name"
+	mptcp_lib_make_file $name 1024 $ksize
+	dd if=/dev/urandom conv=notrunc of="$name" oflag=append bs=1 count=$rem 2> /dev/null
 
 	echo "Created $name (size $(du -b "$name")) containing data sent by $who"
 }
@@ -635,12 +571,12 @@ run_tests_lo()
 	fi
 
 	# skip if we don't want v6
-	if ! $ipv6 && is_v6 "${connect_addr}"; then
+	if ! $ipv6 && mptcp_lib_is_v6 "${connect_addr}"; then
 		return 0
 	fi
 
 	local local_addr
-	if is_v6 "${connect_addr}"; then
+	if mptcp_lib_is_v6 "${connect_addr}"; then
 		local_addr="::"
 	else
 		local_addr="0.0.0.0"
@@ -708,7 +644,7 @@ run_test_transparent()
 	TEST_GROUP="${msg}"
 
 	# skip if we don't want v6
-	if ! $ipv6 && is_v6 "${connect_addr}"; then
+	if ! $ipv6 && mptcp_lib_is_v6 "${connect_addr}"; then
 		return 0
 	fi
 
@@ -741,7 +677,7 @@ EOF
 	fi
 
 	local local_addr
-	if is_v6 "${connect_addr}"; then
+	if mptcp_lib_is_v6 "${connect_addr}"; then
 		local_addr="::"
 		r6flag="-6"
 	else
diff --git a/tools/testing/selftests/net/mptcp/mptcp_join.sh b/tools/testing/selftests/net/mptcp/mptcp_join.sh
index 3c94f2f194d68..8362ea454af38 100755
--- a/tools/testing/selftests/net/mptcp/mptcp_join.sh
+++ b/tools/testing/selftests/net/mptcp/mptcp_join.sh
@@ -511,13 +511,6 @@ get_failed_tests_ids()
 	done | sort -n
 }
 
-print_file_err()
-{
-	ls -l "$1" 1>&2
-	echo -n "Trailing bytes are: "
-	tail -c 27 "$1"
-}
-
 check_transfer()
 {
 	local in=$1
@@ -548,8 +541,8 @@ check_transfer()
 		local sum=$((0${a} + 0${b}))
 		if [ $check_invert -eq 0 ] || [ $sum -ne $((0xff)) ]; then
 			fail_test "$what does not match (in, out):"
-			print_file_err "$in"
-			print_file_err "$out"
+			mptcp_lib_print_file_err "$in"
+			mptcp_lib_print_file_err "$out"
 
 			return 1
 		else
@@ -587,49 +580,9 @@ link_failure()
 	done
 }
 
-# $1: IP address
-is_v6()
-{
-	[ -z "${1##*:*}" ]
-}
-
-# $1: ns, $2: port
-wait_local_port_listen()
-{
-	local listener_ns="${1}"
-	local port="${2}"
-
-	local port_hex
-	port_hex="$(printf "%04X" "${port}")"
-
-	local i
-	for i in $(seq 10); do
-		ip netns exec "${listener_ns}" cat /proc/net/tcp* | \
-			awk "BEGIN {rc=1} {if (\$2 ~ /:${port_hex}\$/ && \$4 ~ /0A/) {rc=0; exit}} END {exit rc}" &&
-			break
-		sleep 0.1
-	done
-}
-
-# $1: ns ; $2: counter
-get_counter()
-{
-	local ns="${1}"
-	local counter="${2}"
-	local count
-
-	count=$(ip netns exec ${ns} nstat -asz "${counter}" | awk 'NR==1 {next} {print $2}')
-	if [ -z "${count}" ]; then
-		mptcp_lib_fail_if_expected_feature "${counter} counter"
-		return 1
-	fi
-
-	echo "${count}"
-}
-
 rm_addr_count()
 {
-	get_counter "${1}" "MPTcpExtRmAddr"
+	mptcp_lib_get_counter "${1}" "MPTcpExtRmAddr"
 }
 
 # $1: ns, $2: old rm_addr counter in $ns
@@ -649,7 +602,7 @@ wait_rm_addr()
 
 rm_sf_count()
 {
-	get_counter "${1}" "MPTcpExtRmSubflow"
+	mptcp_lib_get_counter "${1}" "MPTcpExtRmSubflow"
 }
 
 # $1: ns, $2: old rm_sf counter in $ns
@@ -672,26 +625,20 @@ wait_mpj()
 	local ns="${1}"
 	local cnt old_cnt
 
-	old_cnt=$(get_counter ${ns} "MPTcpExtMPJoinAckRx")
+	old_cnt=$(mptcp_lib_get_counter ${ns} "MPTcpExtMPJoinAckRx")
 
 	local i
 	for i in $(seq 10); do
-		cnt=$(get_counter ${ns} "MPTcpExtMPJoinAckRx")
+		cnt=$(mptcp_lib_get_counter ${ns} "MPTcpExtMPJoinAckRx")
 		[ "$cnt" = "${old_cnt}" ] || break
 		sleep 0.1
 	done
 }
 
-kill_wait()
-{
-	kill $1 > /dev/null 2>&1
-	wait $1 2>/dev/null
-}
-
 kill_events_pids()
 {
-	kill_wait $evts_ns1_pid
-	kill_wait $evts_ns2_pid
+	mptcp_lib_kill_wait $evts_ns1_pid
+	mptcp_lib_kill_wait $evts_ns2_pid
 }
 
 kill_tests_wait()
@@ -901,7 +848,7 @@ pm_nl_set_endpoint()
 		local id=10
 		while [ $add_nr_ns1 -gt 0 ]; do
 			local addr
-			if is_v6 "${connect_addr}"; then
+			if mptcp_lib_is_v6 "${connect_addr}"; then
 				addr="dead:beef:$counter::1"
 			else
 				addr="10.0.$counter.1"
@@ -953,7 +900,7 @@ pm_nl_set_endpoint()
 		local id=20
 		while [ $add_nr_ns2 -gt 0 ]; do
 			local addr
-			if is_v6 "${connect_addr}"; then
+			if mptcp_lib_is_v6 "${connect_addr}"; then
 				addr="dead:beef:$counter::2"
 			else
 				addr="10.0.$counter.2"
@@ -995,7 +942,7 @@ pm_nl_set_endpoint()
 			pm_nl_flush_endpoint ${connector_ns}
 		elif [ $rm_nr_ns2 -eq 9 ]; then
 			local addr
-			if is_v6 "${connect_addr}"; then
+			if mptcp_lib_is_v6 "${connect_addr}"; then
 				addr="dead:beef:1::2"
 			else
 				addr="10.0.1.2"
@@ -1117,7 +1064,7 @@ do_transfer()
 	fi
 	local spid=$!
 
-	wait_local_port_listen "${listener_ns}" "${port}"
+	mptcp_lib_wait_local_port_listen "${listener_ns}" "${port}"
 
 	extra_cl_args="$extra_args $extra_cl_args"
 	if [ "$test_linkfail" -eq 0 ];then
@@ -1199,8 +1146,7 @@ make_file()
 	local who=$2
 	local size=$3
 
-	dd if=/dev/urandom of="$name" bs=1024 count=$size 2> /dev/null
-	echo -e "\nMPTCP_TEST_FILE_END_MARKER" >> "$name"
+	mptcp_lib_make_file $name 1024 $size
 
 	print_info "Test file (size $size KB) for $who"
 }
@@ -1284,7 +1230,7 @@ chk_csum_nr()
 	fi
 
 	print_check "sum"
-	count=$(get_counter ${ns1} "MPTcpExtDataCsumErr")
+	count=$(mptcp_lib_get_counter ${ns1} "MPTcpExtDataCsumErr")
 	if [ "$count" != "$csum_ns1" ]; then
 		extra_msg="$extra_msg ns1=$count"
 	fi
@@ -1297,7 +1243,7 @@ chk_csum_nr()
 		print_ok
 	fi
 	print_check "csum"
-	count=$(get_counter ${ns2} "MPTcpExtDataCsumErr")
+	count=$(mptcp_lib_get_counter ${ns2} "MPTcpExtDataCsumErr")
 	if [ "$count" != "$csum_ns2" ]; then
 		extra_msg="$extra_msg ns2=$count"
 	fi
@@ -1341,7 +1287,7 @@ chk_fail_nr()
 	fi
 
 	print_check "ftx"
-	count=$(get_counter ${ns_tx} "MPTcpExtMPFailTx")
+	count=$(mptcp_lib_get_counter ${ns_tx} "MPTcpExtMPFailTx")
 	if [ "$count" != "$fail_tx" ]; then
 		extra_msg="$extra_msg,tx=$count"
 	fi
@@ -1355,7 +1301,7 @@ chk_fail_nr()
 	fi
 
 	print_check "failrx"
-	count=$(get_counter ${ns_rx} "MPTcpExtMPFailRx")
+	count=$(mptcp_lib_get_counter ${ns_rx} "MPTcpExtMPFailRx")
 	if [ "$count" != "$fail_rx" ]; then
 		extra_msg="$extra_msg,rx=$count"
 	fi
@@ -1388,7 +1334,7 @@ chk_fclose_nr()
 	fi
 
 	print_check "ctx"
-	count=$(get_counter ${ns_tx} "MPTcpExtMPFastcloseTx")
+	count=$(mptcp_lib_get_counter ${ns_tx} "MPTcpExtMPFastcloseTx")
 	if [ -z "$count" ]; then
 		print_skip
 	elif [ "$count" != "$fclose_tx" ]; then
@@ -1399,7 +1345,7 @@ chk_fclose_nr()
 	fi
 
 	print_check "fclzrx"
-	count=$(get_counter ${ns_rx} "MPTcpExtMPFastcloseRx")
+	count=$(mptcp_lib_get_counter ${ns_rx} "MPTcpExtMPFastcloseRx")
 	if [ -z "$count" ]; then
 		print_skip
 	elif [ "$count" != "$fclose_rx" ]; then
@@ -1429,7 +1375,7 @@ chk_rst_nr()
 	fi
 
 	print_check "rtx"
-	count=$(get_counter ${ns_tx} "MPTcpExtMPRstTx")
+	count=$(mptcp_lib_get_counter ${ns_tx} "MPTcpExtMPRstTx")
 	if [ -z "$count" ]; then
 		print_skip
 	# accept more rst than expected except if we don't expect any
@@ -1441,7 +1387,7 @@ chk_rst_nr()
 	fi
 
 	print_check "rstrx"
-	count=$(get_counter ${ns_rx} "MPTcpExtMPRstRx")
+	count=$(mptcp_lib_get_counter ${ns_rx} "MPTcpExtMPRstRx")
 	if [ -z "$count" ]; then
 		print_skip
 	# accept more rst than expected except if we don't expect any
@@ -1462,7 +1408,7 @@ chk_infi_nr()
 	local count
 
 	print_check "itx"
-	count=$(get_counter ${ns2} "MPTcpExtInfiniteMapTx")
+	count=$(mptcp_lib_get_counter ${ns2} "MPTcpExtInfiniteMapTx")
 	if [ -z "$count" ]; then
 		print_skip
 	elif [ "$count" != "$infi_tx" ]; then
@@ -1472,7 +1418,7 @@ chk_infi_nr()
 	fi
 
 	print_check "infirx"
-	count=$(get_counter ${ns1} "MPTcpExtInfiniteMapRx")
+	count=$(mptcp_lib_get_counter ${ns1} "MPTcpExtInfiniteMapRx")
 	if [ -z "$count" ]; then
 		print_skip
 	elif [ "$count" != "$infi_rx" ]; then
@@ -1501,7 +1447,7 @@ chk_join_nr()
 	fi
 
 	print_check "syn"
-	count=$(get_counter ${ns1} "MPTcpExtMPJoinSynRx")
+	count=$(mptcp_lib_get_counter ${ns1} "MPTcpExtMPJoinSynRx")
 	if [ -z "$count" ]; then
 		print_skip
 	elif [ "$count" != "$syn_nr" ]; then
@@ -1512,7 +1458,7 @@ chk_join_nr()
 
 	print_check "synack"
 	with_cookie=$(ip netns exec $ns2 sysctl -n net.ipv4.tcp_syncookies)
-	count=$(get_counter ${ns2} "MPTcpExtMPJoinSynAckRx")
+	count=$(mptcp_lib_get_counter ${ns2} "MPTcpExtMPJoinSynAckRx")
 	if [ -z "$count" ]; then
 		print_skip
 	elif [ "$count" != "$syn_ack_nr" ]; then
@@ -1529,7 +1475,7 @@ chk_join_nr()
 	fi
 
 	print_check "ack"
-	count=$(get_counter ${ns1} "MPTcpExtMPJoinAckRx")
+	count=$(mptcp_lib_get_counter ${ns1} "MPTcpExtMPJoinAckRx")
 	if [ -z "$count" ]; then
 		print_skip
 	elif [ "$count" != "$ack_nr" ]; then
@@ -1562,8 +1508,8 @@ chk_stale_nr()
 
 	print_check "stale"
 
-	stale_nr=$(get_counter ${ns} "MPTcpExtSubflowStale")
-	recover_nr=$(get_counter ${ns} "MPTcpExtSubflowRecover")
+	stale_nr=$(mptcp_lib_get_counter ${ns} "MPTcpExtSubflowStale")
+	recover_nr=$(mptcp_lib_get_counter ${ns} "MPTcpExtSubflowRecover")
 	if [ -z "$stale_nr" ] || [ -z "$recover_nr" ]; then
 		print_skip
 	elif [ $stale_nr -lt $stale_min ] ||
@@ -1600,7 +1546,7 @@ chk_add_nr()
 	timeout=$(ip netns exec $ns1 sysctl -n net.mptcp.add_addr_timeout)
 
 	print_check "add"
-	count=$(get_counter ${ns2} "MPTcpExtAddAddr")
+	count=$(mptcp_lib_get_counter ${ns2} "MPTcpExtAddAddr")
 	if [ -z "$count" ]; then
 		print_skip
 	# if the test configured a short timeout tolerate greater then expected
@@ -1612,7 +1558,7 @@ chk_add_nr()
 	fi
 
 	print_check "echo"
-	count=$(get_counter ${ns1} "MPTcpExtEchoAdd")
+	count=$(mptcp_lib_get_counter ${ns1} "MPTcpExtEchoAdd")
 	if [ -z "$count" ]; then
 		print_skip
 	elif [ "$count" != "$echo_nr" ]; then
@@ -1623,7 +1569,7 @@ chk_add_nr()
 
 	if [ $port_nr -gt 0 ]; then
 		print_check "pt"
-		count=$(get_counter ${ns2} "MPTcpExtPortAdd")
+		count=$(mptcp_lib_get_counter ${ns2} "MPTcpExtPortAdd")
 		if [ -z "$count" ]; then
 			print_skip
 		elif [ "$count" != "$port_nr" ]; then
@@ -1633,7 +1579,7 @@ chk_add_nr()
 		fi
 
 		print_check "syn"
-		count=$(get_counter ${ns1} "MPTcpExtMPJoinPortSynRx")
+		count=$(mptcp_lib_get_counter ${ns1} "MPTcpExtMPJoinPortSynRx")
 		if [ -z "$count" ]; then
 			print_skip
 		elif [ "$count" != "$syn_nr" ]; then
@@ -1644,7 +1590,7 @@ chk_add_nr()
 		fi
 
 		print_check "synack"
-		count=$(get_counter ${ns2} "MPTcpExtMPJoinPortSynAckRx")
+		count=$(mptcp_lib_get_counter ${ns2} "MPTcpExtMPJoinPortSynAckRx")
 		if [ -z "$count" ]; then
 			print_skip
 		elif [ "$count" != "$syn_ack_nr" ]; then
@@ -1655,7 +1601,7 @@ chk_add_nr()
 		fi
 
 		print_check "ack"
-		count=$(get_counter ${ns1} "MPTcpExtMPJoinPortAckRx")
+		count=$(mptcp_lib_get_counter ${ns1} "MPTcpExtMPJoinPortAckRx")
 		if [ -z "$count" ]; then
 			print_skip
 		elif [ "$count" != "$ack_nr" ]; then
@@ -1666,7 +1612,7 @@ chk_add_nr()
 		fi
 
 		print_check "syn"
-		count=$(get_counter ${ns1} "MPTcpExtMismatchPortSynRx")
+		count=$(mptcp_lib_get_counter ${ns1} "MPTcpExtMismatchPortSynRx")
 		if [ -z "$count" ]; then
 			print_skip
 		elif [ "$count" != "$mis_syn_nr" ]; then
@@ -1677,7 +1623,7 @@ chk_add_nr()
 		fi
 
 		print_check "ack"
-		count=$(get_counter ${ns1} "MPTcpExtMismatchPortAckRx")
+		count=$(mptcp_lib_get_counter ${ns1} "MPTcpExtMismatchPortAckRx")
 		if [ -z "$count" ]; then
 			print_skip
 		elif [ "$count" != "$mis_ack_nr" ]; then
@@ -1699,7 +1645,7 @@ chk_add_tx_nr()
 	timeout=$(ip netns exec $ns1 sysctl -n net.mptcp.add_addr_timeout)
 
 	print_check "add TX"
-	count=$(get_counter ${ns1} "MPTcpExtAddAddrTx")
+	count=$(mptcp_lib_get_counter ${ns1} "MPTcpExtAddAddrTx")
 	if [ -z "$count" ]; then
 		print_skip
 	# if the test configured a short timeout tolerate greater then expected
@@ -1711,7 +1657,7 @@ chk_add_tx_nr()
 	fi
 
 	print_check "echo TX"
-	count=$(get_counter ${ns2} "MPTcpExtEchoAddTx")
+	count=$(mptcp_lib_get_counter ${ns2} "MPTcpExtEchoAddTx")
 	if [ -z "$count" ]; then
 		print_skip
 	elif [ "$count" != "$echo_tx_nr" ]; then
@@ -1749,7 +1695,7 @@ chk_rm_nr()
 	fi
 
 	print_check "rm"
-	count=$(get_counter ${addr_ns} "MPTcpExtRmAddr")
+	count=$(mptcp_lib_get_counter ${addr_ns} "MPTcpExtRmAddr")
 	if [ -z "$count" ]; then
 		print_skip
 	elif [ "$count" != "$rm_addr_nr" ]; then
@@ -1759,13 +1705,13 @@ chk_rm_nr()
 	fi
 
 	print_check "rmsf"
-	count=$(get_counter ${subflow_ns} "MPTcpExtRmSubflow")
+	count=$(mptcp_lib_get_counter ${subflow_ns} "MPTcpExtRmSubflow")
 	if [ -z "$count" ]; then
 		print_skip
 	elif [ -n "$simult" ]; then
 		local cnt suffix
 
-		cnt=$(get_counter ${addr_ns} "MPTcpExtRmSubflow")
+		cnt=$(mptcp_lib_get_counter ${addr_ns} "MPTcpExtRmSubflow")
 
 		# in case of simult flush, the subflow removal count on each side is
 		# unreliable
@@ -1794,7 +1740,7 @@ chk_rm_tx_nr()
 	local rm_addr_tx_nr=$1
 
 	print_check "rm TX"
-	count=$(get_counter ${ns2} "MPTcpExtRmAddrTx")
+	count=$(mptcp_lib_get_counter ${ns2} "MPTcpExtRmAddrTx")
 	if [ -z "$count" ]; then
 		print_skip
 	elif [ "$count" != "$rm_addr_tx_nr" ]; then
@@ -1811,7 +1757,7 @@ chk_prio_nr()
 	local count
 
 	print_check "ptx"
-	count=$(get_counter ${ns1} "MPTcpExtMPPrioTx")
+	count=$(mptcp_lib_get_counter ${ns1} "MPTcpExtMPPrioTx")
 	if [ -z "$count" ]; then
 		print_skip
 	elif [ "$count" != "$mp_prio_nr_tx" ]; then
@@ -1821,7 +1767,7 @@ chk_prio_nr()
 	fi
 
 	print_check "prx"
-	count=$(get_counter ${ns1} "MPTcpExtMPPrioRx")
+	count=$(mptcp_lib_get_counter ${ns1} "MPTcpExtMPPrioRx")
 	if [ -z "$count" ]; then
 		print_skip
 	elif [ "$count" != "$mp_prio_nr_rx" ]; then
@@ -1867,12 +1813,10 @@ chk_mptcp_info()
 	local cnt2
 	local dump_stats
 
-	print_check "mptcp_info ${info1:0:8}=$exp1:$exp2"
+	print_check "mptcp_info ${info1:0:15}=$exp1:$exp2"
 
-	cnt1=$(ss -N $ns1 -inmHM | grep "$info1:" |
-	       sed -n 's/.*\('"$info1"':\)\([[:digit:]]*\).*$/\2/p;q')
-	cnt2=$(ss -N $ns2 -inmHM | grep "$info2:" |
-	       sed -n 's/.*\('"$info2"':\)\([[:digit:]]*\).*$/\2/p;q')
+	cnt1=$(ss -N $ns1 -inmHM | mptcp_lib_get_info_value "$info1" "$info1")
+	cnt2=$(ss -N $ns2 -inmHM | mptcp_lib_get_info_value "$info2" "$info2")
 	# 'ss' only display active connections and counters that are not 0.
 	[ -z "$cnt1" ] && cnt1=0
 	[ -z "$cnt2" ] && cnt2=0
@@ -1890,6 +1834,42 @@ chk_mptcp_info()
 	fi
 }
 
+# $1: subflows in ns1 ; $2: subflows in ns2
+# number of all subflows, including the initial subflow.
+chk_subflows_total()
+{
+	local cnt1
+	local cnt2
+	local info="subflows_total"
+	local dump_stats
+
+	# if subflows_total counter is supported, use it:
+	if [ -n "$(ss -N $ns1 -inmHM | mptcp_lib_get_info_value $info $info)" ]; then
+		chk_mptcp_info $info $1 $info $2
+		return
+	fi
+
+	print_check "$info $1:$2"
+
+	# if not, count the TCP connections that are in fact MPTCP subflows
+	cnt1=$(ss -N $ns1 -ti state established state syn-sent state syn-recv |
+	       grep -c tcp-ulp-mptcp)
+	cnt2=$(ss -N $ns2 -ti state established state syn-sent state syn-recv |
+	       grep -c tcp-ulp-mptcp)
+
+	if [ "$1" != "$cnt1" ] || [ "$2" != "$cnt2" ]; then
+		fail_test "got subflows $cnt1:$cnt2 expected $1:$2"
+		dump_stats=1
+	else
+		print_ok
+	fi
+
+	if [ "$dump_stats" = 1 ]; then
+		ss -N $ns1 -ti
+		ss -N $ns2 -ti
+	fi
+}
+
 chk_link_usage()
 {
 	local ns=$1
@@ -1921,7 +1901,7 @@ wait_attempt_fail()
 	while [ $time -lt $timeout_ms ]; do
 		local cnt
 
-		cnt=$(get_counter ${ns} "TcpAttemptFails")
+		cnt=$(mptcp_lib_get_counter ${ns} "TcpAttemptFails")
 
 		[ "$cnt" = 1 ] && return 1
 		time=$((time + 100))
@@ -2814,6 +2794,7 @@ backup_tests()
 	fi
 }
 
+SUB_ESTABLISHED=10 # MPTCP_EVENT_SUB_ESTABLISHED
 LISTENER_CREATED=15 #MPTCP_EVENT_LISTENER_CREATED
 LISTENER_CLOSED=16  #MPTCP_EVENT_LISTENER_CLOSED
 
@@ -2848,13 +2829,13 @@ verify_listener_events()
 		return
 	fi
 
-	type=$(grep "type:$e_type," $evt | sed -n 's/.*\(type:\)\([[:digit:]]*\).*$/\2/p;q')
-	family=$(grep "type:$e_type," $evt | sed -n 's/.*\(family:\)\([[:digit:]]*\).*$/\2/p;q')
-	sport=$(grep "type:$e_type," $evt | sed -n 's/.*\(sport:\)\([[:digit:]]*\).*$/\2/p;q')
+	type=$(mptcp_lib_evts_get_info type "$evt" "$e_type")
+	family=$(mptcp_lib_evts_get_info family "$evt" "$e_type")
+	sport=$(mptcp_lib_evts_get_info sport "$evt" "$e_type")
 	if [ $family ] && [ $family = $AF_INET6 ]; then
-		saddr=$(grep "type:$e_type," $evt | sed -n 's/.*\(saddr6:\)\([0-9a-f:.]*\).*$/\2/p;q')
+		saddr=$(mptcp_lib_evts_get_info saddr6 "$evt" "$e_type")
 	else
-		saddr=$(grep "type:$e_type," $evt | sed -n 's/.*\(saddr4:\)\([0-9.]*\).*$/\2/p;q')
+		saddr=$(mptcp_lib_evts_get_info saddr4 "$evt" "$e_type")
 	fi
 
 	if [ $type ] && [ $type = $e_type ] &&
@@ -3249,8 +3230,7 @@ fastclose_tests()
 pedit_action_pkts()
 {
 	tc -n $ns2 -j -s action show action pedit index 100 | \
-		grep "packets" | \
-		sed 's/.*"packets":\([0-9]\+\),.*/\1/'
+		mptcp_lib_get_info_value \"packets\" packets
 }
 
 fail_tests()
@@ -3275,75 +3255,70 @@ fail_tests()
 	fi
 }
 
+# $1: ns ; $2: addr ; $3: id
 userspace_pm_add_addr()
 {
-	local addr=$1
-	local id=$2
+	local evts=$evts_ns1
 	local tk
 
-	tk=$(grep "type:1," "$evts_ns1" |
-	     sed -n 's/.*\(token:\)\([[:digit:]]*\).*$/\2/p;q')
-	ip netns exec $ns1 ./pm_nl_ctl ann $addr token $tk id $id
+	[ "$1" == "$ns2" ] && evts=$evts_ns2
+	tk=$(mptcp_lib_evts_get_info token "$evts")
+
+	ip netns exec $1 ./pm_nl_ctl ann $2 token $tk id $3
 	sleep 1
 }
 
-userspace_pm_rm_sf_addr_ns1()
+# $1: ns ; $2: id
+userspace_pm_rm_addr()
 {
-	local addr=$1
-	local id=$2
-	local tk sp da dp
-	local cnt_addr cnt_sf
-
-	tk=$(grep "type:1," "$evts_ns1" |
-	     sed -n 's/.*\(token:\)\([[:digit:]]*\).*$/\2/p;q')
-	sp=$(grep "type:10" "$evts_ns1" |
-	     sed -n 's/.*\(sport:\)\([[:digit:]]*\).*$/\2/p;q')
-	da=$(grep "type:10" "$evts_ns1" |
-	     sed -n 's/.*\(daddr6:\)\([0-9a-f:.]*\).*$/\2/p;q')
-	dp=$(grep "type:10" "$evts_ns1" |
-	     sed -n 's/.*\(dport:\)\([[:digit:]]*\).*$/\2/p;q')
-	cnt_addr=$(rm_addr_count ${ns1})
-	cnt_sf=$(rm_sf_count ${ns1})
-	ip netns exec $ns1 ./pm_nl_ctl rem token $tk id $id
-	ip netns exec $ns1 ./pm_nl_ctl dsf lip "::ffff:$addr" \
-				lport $sp rip $da rport $dp token $tk
-	wait_rm_addr $ns1 "${cnt_addr}"
-	wait_rm_sf $ns1 "${cnt_sf}"
+	local evts=$evts_ns1
+	local tk
+	local cnt
+
+	[ "$1" == "$ns2" ] && evts=$evts_ns2
+	tk=$(mptcp_lib_evts_get_info token "$evts")
+
+	cnt=$(rm_addr_count ${1})
+	ip netns exec $1 ./pm_nl_ctl rem token $tk id $2
+	wait_rm_addr $1 "${cnt}"
 }
 
+# $1: ns ; $2: addr ; $3: id
 userspace_pm_add_sf()
 {
-	local addr=$1
-	local id=$2
+	local evts=$evts_ns1
 	local tk da dp
 
-	tk=$(sed -n 's/.*\(token:\)\([[:digit:]]*\).*$/\2/p;q' "$evts_ns2")
-	da=$(sed -n 's/.*\(daddr4:\)\([0-9.]*\).*$/\2/p;q' "$evts_ns2")
-	dp=$(sed -n 's/.*\(dport:\)\([[:digit:]]*\).*$/\2/p;q' "$evts_ns2")
-	ip netns exec $ns2 ./pm_nl_ctl csf lip $addr lid $id \
+	[ "$1" == "$ns2" ] && evts=$evts_ns2
+	tk=$(mptcp_lib_evts_get_info token "$evts")
+	da=$(mptcp_lib_evts_get_info daddr4 "$evts")
+	dp=$(mptcp_lib_evts_get_info dport "$evts")
+
+	ip netns exec $1 ./pm_nl_ctl csf lip $2 lid $3 \
 				rip $da rport $dp token $tk
 	sleep 1
 }
 
-userspace_pm_rm_sf_addr_ns2()
+# $1: ns ; $2: addr $3: event type
+userspace_pm_rm_sf()
 {
-	local addr=$1
-	local id=$2
+	local evts=$evts_ns1
+	local t=${3:-1}
+	local ip=4
 	local tk da dp sp
-	local cnt_addr cnt_sf
-
-	tk=$(sed -n 's/.*\(token:\)\([[:digit:]]*\).*$/\2/p;q' "$evts_ns2")
-	da=$(sed -n 's/.*\(daddr4:\)\([0-9.]*\).*$/\2/p;q' "$evts_ns2")
-	dp=$(sed -n 's/.*\(dport:\)\([[:digit:]]*\).*$/\2/p;q' "$evts_ns2")
-	sp=$(grep "type:10" "$evts_ns2" |
-	     sed -n 's/.*\(sport:\)\([[:digit:]]*\).*$/\2/p;q')
-	cnt_addr=$(rm_addr_count ${ns2})
-	cnt_sf=$(rm_sf_count ${ns2})
-	ip netns exec $ns2 ./pm_nl_ctl rem token $tk id $id
-	ip netns exec $ns2 ./pm_nl_ctl dsf lip $addr lport $sp \
+	local cnt
+
+	[ "$1" == "$ns2" ] && evts=$evts_ns2
+	if mptcp_lib_is_v6 $2; then ip=6; fi
+	tk=$(mptcp_lib_evts_get_info token "$evts")
+	da=$(mptcp_lib_evts_get_info "daddr$ip" "$evts" $t)
+	dp=$(mptcp_lib_evts_get_info dport "$evts" $t)
+	sp=$(mptcp_lib_evts_get_info sport "$evts" $t)
+
+	cnt=$(rm_sf_count ${1})
+	ip netns exec $1 ./pm_nl_ctl dsf lip $2 lport $sp \
 				rip $da rport $dp token $tk
-	wait_rm_addr $ns2 "${cnt_addr}"
-	wait_rm_sf $ns2 "${cnt_sf}"
+	wait_rm_sf $1 "${cnt}"
 }
 
 userspace_tests()
@@ -3430,14 +3405,17 @@ userspace_tests()
 			run_tests $ns1 $ns2 10.0.1.1 &
 		local tests_pid=$!
 		wait_mpj $ns1
-		userspace_pm_add_addr 10.0.2.1 10
+		userspace_pm_add_addr $ns1 10.0.2.1 10
 		chk_join_nr 1 1 1
 		chk_add_nr 1 1
 		chk_mptcp_info subflows 1 subflows 1
+		chk_subflows_total 2 2
 		chk_mptcp_info add_addr_signal 1 add_addr_accepted 1
-		userspace_pm_rm_sf_addr_ns1 10.0.2.1 10
+		userspace_pm_rm_addr $ns1 10
+		userspace_pm_rm_sf $ns1 "::ffff:10.0.2.1" $SUB_ESTABLISHED
 		chk_rm_nr 1 1 invert
 		chk_mptcp_info subflows 0 subflows 0
+		chk_subflows_total 1 1
 		kill_events_pids
 		wait $tests_pid
 	fi
@@ -3451,12 +3429,84 @@ userspace_tests()
 			run_tests $ns1 $ns2 10.0.1.1 &
 		local tests_pid=$!
 		wait_mpj $ns2
-		userspace_pm_add_sf 10.0.3.2 20
+		userspace_pm_add_sf $ns2 10.0.3.2 20
 		chk_join_nr 1 1 1
 		chk_mptcp_info subflows 1 subflows 1
-		userspace_pm_rm_sf_addr_ns2 10.0.3.2 20
+		chk_subflows_total 2 2
+		userspace_pm_rm_addr $ns2 20
+		userspace_pm_rm_sf $ns2 10.0.3.2 $SUB_ESTABLISHED
 		chk_rm_nr 1 1
 		chk_mptcp_info subflows 0 subflows 0
+		chk_subflows_total 1 1
+		kill_events_pids
+		wait $tests_pid
+	fi
+
+	# userspace pm create id 0 subflow
+	if reset_with_events "userspace pm create id 0 subflow" &&
+	   continue_if mptcp_lib_has_file '/proc/sys/net/mptcp/pm_type'; then
+		set_userspace_pm $ns2
+		pm_nl_set_limits $ns1 0 1
+		speed=5 \
+			run_tests $ns1 $ns2 10.0.1.1 &
+		local tests_pid=$!
+		wait_mpj $ns2
+		chk_mptcp_info subflows 0 subflows 0
+		chk_subflows_total 1 1
+		userspace_pm_add_sf $ns2 10.0.3.2 0
+		chk_join_nr 1 1 1
+		chk_mptcp_info subflows 1 subflows 1
+		chk_subflows_total 2 2
+		kill_events_pids
+		wait $tests_pid
+	fi
+
+	# userspace pm remove initial subflow
+	if reset_with_events "userspace pm remove initial subflow" &&
+	   continue_if mptcp_lib_has_file '/proc/sys/net/mptcp/pm_type'; then
+		set_userspace_pm $ns2
+		pm_nl_set_limits $ns1 0 1
+		speed=5 \
+			run_tests $ns1 $ns2 10.0.1.1 &
+		local tests_pid=$!
+		wait_mpj $ns2
+		userspace_pm_add_sf $ns2 10.0.3.2 20
+		chk_join_nr 1 1 1
+		chk_mptcp_info subflows 1 subflows 1
+		chk_subflows_total 2 2
+		userspace_pm_rm_sf $ns2 10.0.1.2
+		# we don't look at the counter linked to the RM_ADDR but
+		# to the one linked to the subflows that have been removed
+		chk_rm_nr 0 1
+		chk_rst_nr 0 0 invert
+		chk_mptcp_info subflows 1 subflows 1
+		chk_subflows_total 1 1
+		kill_events_pids
+		wait $tests_pid
+	fi
+
+	# userspace pm send RM_ADDR for ID 0
+	if reset_with_events "userspace pm send RM_ADDR for ID 0" &&
+	   continue_if mptcp_lib_has_file '/proc/sys/net/mptcp/pm_type'; then
+		set_userspace_pm $ns1
+		pm_nl_set_limits $ns2 1 1
+		speed=5 \
+			run_tests $ns1 $ns2 10.0.1.1 &
+		local tests_pid=$!
+		wait_mpj $ns1
+		userspace_pm_add_addr $ns1 10.0.2.1 10
+		chk_join_nr 1 1 1
+		chk_add_nr 1 1
+		chk_mptcp_info subflows 1 subflows 1
+		chk_subflows_total 2 2
+		chk_mptcp_info add_addr_signal 1 add_addr_accepted 1
+		userspace_pm_rm_addr $ns1 0
+		# we don't look at the counter linked to the subflows that
+		# have been removed but to the one linked to the RM_ADDR
+		chk_rm_nr 1 0 invert
+		chk_rst_nr 0 0 invert
+		chk_mptcp_info subflows 1 subflows 1
+		chk_subflows_total 1 1
 		kill_events_pids
 		wait $tests_pid
 	fi
diff --git a/tools/testing/selftests/net/mptcp/mptcp_lib.sh b/tools/testing/selftests/net/mptcp/mptcp_lib.sh
index 92a5befe80394..022262a2cfe0e 100644
--- a/tools/testing/selftests/net/mptcp/mptcp_lib.sh
+++ b/tools/testing/selftests/net/mptcp/mptcp_lib.sh
@@ -207,3 +207,94 @@ mptcp_lib_result_print_all_tap() {
 		printf "%s\n" "${subtest}"
 	done
 }
+
+# get the value of keyword $1 in the line marked by keyword $2
+mptcp_lib_get_info_value() {
+	grep "${2}" | sed -n 's/.*\('"${1}"':\)\([0-9a-f:.]*\).*$/\2/p;q'
+}
+
+# $1: info name ; $2: evts_ns ; $3: event type
+mptcp_lib_evts_get_info() {
+	mptcp_lib_get_info_value "${1}" "^type:${3:-1}," < "${2}"
+}
+
+# $1: PID
+mptcp_lib_kill_wait() {
+	[ "${1}" -eq 0 ] && return 0
+
+	kill -SIGUSR1 "${1}" > /dev/null 2>&1
+	kill "${1}" > /dev/null 2>&1
+	wait "${1}" 2>/dev/null
+}
+
+# $1: IP address
+mptcp_lib_is_v6() {
+	[ -z "${1##*:*}" ]
+}
+
+# $1: ns, $2: MIB counter
+mptcp_lib_get_counter() {
+	local ns="${1}"
+	local counter="${2}"
+	local count
+
+	count=$(ip netns exec "${ns}" nstat -asz "${counter}" |
+		awk 'NR==1 {next} {print $2}')
+	if [ -z "${count}" ]; then
+		mptcp_lib_fail_if_expected_feature "${counter} counter"
+		return 1
+	fi
+
+	echo "${count}"
+}
+
+mptcp_lib_make_file() {
+	local name="${1}"
+	local bs="${2}"
+	local size="${3}"
+
+	dd if=/dev/urandom of="${name}" bs="${bs}" count="${size}" 2> /dev/null
+	echo -e "\nMPTCP_TEST_FILE_END_MARKER" >> "${name}"
+}
+
+# $1: file
+mptcp_lib_print_file_err() {
+	ls -l "${1}" 1>&2
+	echo "Trailing bytes are: "
+	tail -c 27 "${1}"
+}
+
+# $1: input file ; $2: output file ; $3: what kind of file
+mptcp_lib_check_transfer() {
+	local in="${1}"
+	local out="${2}"
+	local what="${3}"
+
+	if ! cmp "$in" "$out" > /dev/null 2>&1; then
+		echo "[ FAIL ] $what does not match (in, out):"
+		mptcp_lib_print_file_err "$in"
+		mptcp_lib_print_file_err "$out"
+
+		return 1
+	fi
+
+	return 0
+}
+
+# $1: ns, $2: port
+mptcp_lib_wait_local_port_listen() {
+	local listener_ns="${1}"
+	local port="${2}"
+
+	local port_hex
+	port_hex="$(printf "%04X" "${port}")"
+
+	local _
+	for _ in $(seq 10); do
+		ip netns exec "${listener_ns}" cat /proc/net/tcp* | \
+			awk "BEGIN {rc=1} {if (\$2 ~ /:${port_hex}\$/ && \$4 ~ /0A/) \
+			     {rc=0; exit}} END {exit rc}" &&
+			break
+		sleep 0.1
+	done
+}
diff --git a/tools/testing/selftests/net/mptcp/mptcp_sockopt.sh b/tools/testing/selftests/net/mptcp/mptcp_sockopt.sh
index a817af6616ec9..c643872ddf478 100755
--- a/tools/testing/selftests/net/mptcp/mptcp_sockopt.sh
+++ b/tools/testing/selftests/net/mptcp/mptcp_sockopt.sh
@@ -135,38 +135,6 @@ check_mark()
 	return 0
 }
 
-print_file_err()
-{
-	ls -l "$1" 1>&2
-	echo "Trailing bytes are: "
-	tail -c 27 "$1"
-}
-
-check_transfer()
-{
-	local in=$1
-	local out=$2
-	local what=$3
-
-	cmp "$in" "$out" > /dev/null 2>&1
-	if [ $? -ne 0 ] ;then
-		echo "[ FAIL ] $what does not match (in, out):"
-		print_file_err "$in"
-		print_file_err "$out"
-		ret=1
-
-		return 1
-	fi
-
-	return 0
-}
-
-# $1: IP address
-is_v6()
-{
-	[ -z "${1##*:*}" ]
-}
-
 do_transfer()
 {
 	local listener_ns="$1"
@@ -183,7 +151,7 @@ do_transfer()
 	local mptcp_connect="./mptcp_connect -r 20"
 
 	local local_addr ip
-	if is_v6 "${connect_addr}"; then
+	if mptcp_lib_is_v6 "${connect_addr}"; then
 		local_addr="::"
 		ip=ipv6
 	else
@@ -238,7 +206,7 @@ do_transfer()
 		check_mark $connector_ns 4 || retc=1
 	fi
 
-	check_transfer $cin $sout "file received by server"
+	mptcp_lib_check_transfer $cin $sout "file received by server"
 	rets=$?
 
 	mptcp_lib_result_code "${retc}" "mark ${ip}"
@@ -257,8 +225,7 @@ make_file()
 	local who=$2
 	local size=$3
 
-	dd if=/dev/urandom of="$name" bs=1024 count=$size 2> /dev/null
-	echo -e "\nMPTCP_TEST_FILE_END_MARKER" >> "$name"
+	mptcp_lib_make_file $name 1024 $size
 
 	echo "Created $name (size $size KB) containing data sent by $who"
 }
diff --git a/tools/testing/selftests/net/mptcp/simult_flows.sh b/tools/testing/selftests/net/mptcp/simult_flows.sh
index ce9203b817f88..ae8ad5d6fb9da 100755
--- a/tools/testing/selftests/net/mptcp/simult_flows.sh
+++ b/tools/testing/selftests/net/mptcp/simult_flows.sh
@@ -123,23 +123,6 @@ setup()
 	grep -q ' kmemleak_init$\| lockdep_init$\| kasan_init$\| prove_locking$' /proc/kallsyms && slack=$((slack+550))
 }
 
-# $1: ns, $2: port
-wait_local_port_listen()
-{
-	local listener_ns="${1}"
-	local port="${2}"
-
-	local port_hex i
-
-	port_hex="$(printf "%04X" "${port}")"
-	for i in $(seq 10); do
-		ip netns exec "${listener_ns}" cat /proc/net/tcp* | \
-			awk "BEGIN {rc=1} {if (\$2 ~ /:${port_hex}\$/ && \$4 ~ /0A/) {rc=0; exit}} END {exit rc}" &&
-			break
-		sleep 0.1
-	done
-}
-
 do_transfer()
 {
 	local cin=$1
@@ -179,7 +162,7 @@ do_transfer()
 				0.0.0.0 < "$sin" > "$sout" &
 	local spid=$!
 
-	wait_local_port_listen "${ns3}" "${port}"
+	mptcp_lib_wait_local_port_listen "${ns3}" "${port}"
 
 	timeout ${timeout_test} \
 		ip netns exec ${ns1} \
diff --git a/tools/testing/selftests/net/mptcp/userspace_pm.sh b/tools/testing/selftests/net/mptcp/userspace_pm.sh
index b25a3e33eb253..6167837f48e17 100755
--- a/tools/testing/selftests/net/mptcp/userspace_pm.sh
+++ b/tools/testing/selftests/net/mptcp/userspace_pm.sh
@@ -108,15 +108,6 @@ test_fail()
 	mptcp_lib_result_fail "${test_name}"
 }
 
-kill_wait()
-{
-	[ $1 -eq 0 ] && return 0
-
-	kill -SIGUSR1 $1 > /dev/null 2>&1
-	kill $1 > /dev/null 2>&1
-	wait $1 2>/dev/null
-}
-
 # This function is used in the cleanup trap
 #shellcheck disable=SC2317
 cleanup()
@@ -128,7 +119,7 @@ cleanup()
 	for pid in $client4_pid $server4_pid $client6_pid $server6_pid\
 		   $server_evts_pid $client_evts_pid
 	do
-		kill_wait $pid
+		mptcp_lib_kill_wait $pid
 	done
 
 	local netns
@@ -173,22 +164,12 @@ print_title "Init"
 print_test "Created network namespaces ns1, ns2"
 test_pass
 
-make_file()
-{
-	# Store a chunk of data in a file to transmit over an MPTCP connection
-	local name=$1
-	local ksize=1
-
-	dd if=/dev/urandom of="$name" bs=2 count=$ksize 2> /dev/null
-	echo -e "\nMPTCP_TEST_FILE_END_MARKER" >> "$name"
-}
-
 make_connection()
 {
 	if [ -z "$file" ]; then
 		file=$(mktemp)
 	fi
-	make_file "$file" "client"
+	mptcp_lib_make_file "$file" 2 1
 
 	local is_v6=$1
 	local app_port=$app4_port
@@ -210,7 +191,7 @@ make_connection()
 	fi
 	:>"$client_evts"
 	if [ $client_evts_pid -ne 0 ]; then
-		kill_wait $client_evts_pid
+		mptcp_lib_kill_wait $client_evts_pid
 	fi
 	ip netns exec "$ns2" ./pm_nl_ctl events >> "$client_evts" 2>&1 &
 	client_evts_pid=$!
@@ -219,7 +200,7 @@ make_connection()
 	fi
 	:>"$server_evts"
 	if [ $server_evts_pid -ne 0 ]; then
-		kill_wait $server_evts_pid
+		mptcp_lib_kill_wait $server_evts_pid
 	fi
 	ip netns exec "$ns1" ./pm_nl_ctl events >> "$server_evts" 2>&1 &
 	server_evts_pid=$!
@@ -247,14 +228,11 @@ make_connection()
 	local server_token
 	local server_serverside
 
-	client_token=$(sed --unbuffered -n 's/.*\(token:\)\([[:digit:]]*\).*$/\2/p;q' "$client_evts")
-	client_port=$(sed --unbuffered -n 's/.*\(sport:\)\([[:digit:]]*\).*$/\2/p;q' "$client_evts")
-	client_serverside=$(sed --unbuffered -n 's/.*\(server_side:\)\([[:digit:]]*\).*$/\2/p;q'\
-				      "$client_evts")
-	server_token=$(grep "type:1," "$server_evts" |
-		       sed --unbuffered -n 's/.*\(token:\)\([[:digit:]]*\).*$/\2/p;q')
-	server_serverside=$(grep "type:1," "$server_evts" |
-			    sed --unbuffered -n 's/.*\(server_side:\)\([[:digit:]]*\).*$/\2/p;q')
+	client_token=$(mptcp_lib_evts_get_info token "$client_evts")
+	client_port=$(mptcp_lib_evts_get_info sport "$client_evts")
+	client_serverside=$(mptcp_lib_evts_get_info server_side "$client_evts")
+	server_token=$(mptcp_lib_evts_get_info token "$server_evts")
+	server_serverside=$(mptcp_lib_evts_get_info server_side "$server_evts")
 
 	print_test "Established IP${is_v6} MPTCP Connection ns2 => ns1"
 	if [ "$client_token" != "" ] && [ "$server_token" != "" ] && [ "$client_serverside" = 0 ] &&
@@ -340,16 +318,16 @@ verify_announce_event()
 	local dport
 	local id
 
-	type=$(sed --unbuffered -n 's/.*\(type:\)\([[:digit:]]*\).*$/\2/p;q' "$evt")
-	token=$(sed --unbuffered -n 's/.*\(token:\)\([[:digit:]]*\).*$/\2/p;q' "$evt")
+	type=$(mptcp_lib_evts_get_info type "$evt" $e_type)
+	token=$(mptcp_lib_evts_get_info token "$evt" $e_type)
 	if [ "$e_af" = "v6" ]
 	then
-		addr=$(sed --unbuffered -n 's/.*\(daddr6:\)\([0-9a-f:.]*\).*$/\2/p;q' "$evt")
+		addr=$(mptcp_lib_evts_get_info daddr6 "$evt" $e_type)
 	else
-		addr=$(sed --unbuffered -n 's/.*\(daddr4:\)\([0-9.]*\).*$/\2/p;q' "$evt")
+		addr=$(mptcp_lib_evts_get_info daddr4 "$evt" $e_type)
 	fi
-	dport=$(sed --unbuffered -n 's/.*\(dport:\)\([[:digit:]]*\).*$/\2/p;q' "$evt")
-	id=$(sed --unbuffered -n 's/.*\(rem_id:\)\([[:digit:]]*\).*$/\2/p;q' "$evt")
+	dport=$(mptcp_lib_evts_get_info dport "$evt" $e_type)
+	id=$(mptcp_lib_evts_get_info rem_id "$evt" $e_type)
 
 	check_expected "type" "token" "addr" "dport" "id"
 }
@@ -367,7 +345,7 @@ test_announce()
 	   $client_addr_id dev ns2eth1 > /dev/null 2>&1
 
 	local type
-	type=$(sed --unbuffered -n 's/.*\(type:\)\([[:digit:]]*\).*$/\2/p;q' "$server_evts")
+	type=$(mptcp_lib_evts_get_info type "$server_evts")
 	print_test "ADD_ADDR 10.0.2.2 (ns2) => ns1, invalid token"
 	if [ "$type" = "" ]
 	then
@@ -446,9 +424,9 @@ verify_remove_event()
 	local token
 	local id
 
-	type=$(sed --unbuffered -n 's/.*\(type:\)\([[:digit:]]*\).*$/\2/p;q' "$evt")
-	token=$(sed --unbuffered -n 's/.*\(token:\)\([[:digit:]]*\).*$/\2/p;q' "$evt")
-	id=$(sed --unbuffered -n 's/.*\(rem_id:\)\([[:digit:]]*\).*$/\2/p;q' "$evt")
+	type=$(mptcp_lib_evts_get_info type "$evt" $e_type)
+	token=$(mptcp_lib_evts_get_info token "$evt" $e_type)
+	id=$(mptcp_lib_evts_get_info rem_id "$evt" $e_type)
 
 	check_expected "type" "token" "id"
 }
@@ -466,7 +444,7 @@ test_remove()
 	   $client_addr_id > /dev/null 2>&1
 	print_test "RM_ADDR id:${client_addr_id} ns2 => ns1, invalid token"
 	local type
-	type=$(sed --unbuffered -n 's/.*\(type:\)\([[:digit:]]*\).*$/\2/p;q' "$server_evts")
+	type=$(mptcp_lib_evts_get_info type "$server_evts")
 	if [ "$type" = "" ]
 	then
 		test_pass
@@ -479,7 +457,7 @@ test_remove()
 	ip netns exec "$ns2" ./pm_nl_ctl rem token "$client4_token" id\
 	   $invalid_id > /dev/null 2>&1
 	print_test "RM_ADDR id:${invalid_id} ns2 => ns1, invalid id"
-	type=$(sed --unbuffered -n 's/.*\(type:\)\([[:digit:]]*\).*$/\2/p;q' "$server_evts")
+	type=$(mptcp_lib_evts_get_info type "$server_evts")
 	if [ "$type" = "" ]
 	then
 		test_pass
@@ -583,19 +561,19 @@ verify_subflow_events()
 		fi
 	fi
 
-	type=$(sed --unbuffered -n 's/.*\(type:\)\([[:digit:]]*\).*$/\2/p;q' "$evt")
-	token=$(sed --unbuffered -n 's/.*\(token:\)\([[:digit:]]*\).*$/\2/p;q' "$evt")
-	family=$(sed --unbuffered -n 's/.*\(family:\)\([[:digit:]]*\).*$/\2/p;q' "$evt")
-	dport=$(sed --unbuffered -n 's/.*\(dport:\)\([[:digit:]]*\).*$/\2/p;q' "$evt")
-	locid=$(sed --unbuffered -n 's/.*\(loc_id:\)\([[:digit:]]*\).*$/\2/p;q' "$evt")
-	remid=$(sed --unbuffered -n 's/.*\(rem_id:\)\([[:digit:]]*\).*$/\2/p;q' "$evt")
+	type=$(mptcp_lib_evts_get_info type "$evt" $e_type)
+	token=$(mptcp_lib_evts_get_info token "$evt" $e_type)
+	family=$(mptcp_lib_evts_get_info family "$evt" $e_type)
+	dport=$(mptcp_lib_evts_get_info dport "$evt" $e_type)
+	locid=$(mptcp_lib_evts_get_info loc_id "$evt" $e_type)
+	remid=$(mptcp_lib_evts_get_info rem_id "$evt" $e_type)
 	if [ "$family" = "$AF_INET6" ]
 	then
-		saddr=$(sed --unbuffered -n 's/.*\(saddr6:\)\([0-9a-f:.]*\).*$/\2/p;q' "$evt")
-		daddr=$(sed --unbuffered -n 's/.*\(daddr6:\)\([0-9a-f:.]*\).*$/\2/p;q' "$evt")
+		saddr=$(mptcp_lib_evts_get_info saddr6 "$evt" $e_type)
+		daddr=$(mptcp_lib_evts_get_info daddr6 "$evt" $e_type)
 	else
-		saddr=$(sed --unbuffered -n 's/.*\(saddr4:\)\([0-9.]*\).*$/\2/p;q' "$evt")
-		daddr=$(sed --unbuffered -n 's/.*\(daddr4:\)\([0-9.]*\).*$/\2/p;q' "$evt")
+		saddr=$(mptcp_lib_evts_get_info saddr4 "$evt" $e_type)
+		daddr=$(mptcp_lib_evts_get_info daddr4 "$evt" $e_type)
 	fi
 
 	check_expected "type" "token" "daddr" "dport" "family" "saddr" "locid" "remid"
@@ -627,10 +605,10 @@ test_subflows()
 			      "10.0.2.2" "$client4_port" "23" "$client_addr_id" "ns1" "ns2"
 
 	# Delete the listener from the client ns, if one was created
-	kill_wait $listener_pid
+	mptcp_lib_kill_wait $listener_pid
 
 	local sport
-	sport=$(sed --unbuffered -n 's/.*\(sport:\)\([[:digit:]]*\).*$/\2/p;q' "$server_evts")
+	sport=$(mptcp_lib_evts_get_info sport "$server_evts" $SUB_ESTABLISHED)
 
 	# DESTROY_SUBFLOW from server to client machine
 	:>"$server_evts"
@@ -666,9 +644,9 @@ test_subflows()
 			      "$client_addr_id" "ns1" "ns2"
 
 	# Delete the listener from the client ns, if one was created
-	kill_wait $listener_pid
+	mptcp_lib_kill_wait $listener_pid
 
-	sport=$(sed --unbuffered -n 's/.*\(sport:\)\([[:digit:]]*\).*$/\2/p;q' "$server_evts")
+	sport=$(mptcp_lib_evts_get_info sport "$server_evts" $SUB_ESTABLISHED)
 
 	# DESTROY_SUBFLOW6 from server to client machine
 	:>"$server_evts"
@@ -705,9 +683,9 @@ test_subflows()
 			      "$client_addr_id" "ns1" "ns2"
 
 	# Delete the listener from the client ns, if one was created
-	kill_wait $listener_pid
+	mptcp_lib_kill_wait $listener_pid
 
-	sport=$(sed --unbuffered -n 's/.*\(sport:\)\([[:digit:]]*\).*$/\2/p;q' "$server_evts")
+	sport=$(mptcp_lib_evts_get_info sport "$server_evts" $SUB_ESTABLISHED)
 
 	# DESTROY_SUBFLOW from server to client machine
 	:>"$server_evts"
@@ -743,9 +721,9 @@ test_subflows()
 			      "10.0.2.1" "$app4_port" "23" "$server_addr_id" "ns2" "ns1"
 
 	# Delete the listener from the server ns, if one was created
-	kill_wait $listener_pid
+	mptcp_lib_kill_wait $listener_pid
 
-	sport=$(sed --unbuffered -n 's/.*\(sport:\)\([[:digit:]]*\).*$/\2/p;q' "$client_evts")
+	sport=$(mptcp_lib_evts_get_info sport "$client_evts" $SUB_ESTABLISHED)
 
 	# DESTROY_SUBFLOW from client to server machine
 	:>"$client_evts"
@@ -782,9 +760,9 @@ test_subflows()
 			      "$server_addr_id" "ns2" "ns1"
 
 	# Delete the listener from the server ns, if one was created
-	kill_wait $listener_pid
+	mptcp_lib_kill_wait $listener_pid
 
-	sport=$(sed --unbuffered -n 's/.*\(sport:\)\([[:digit:]]*\).*$/\2/p;q' "$client_evts")
+	sport=$(mptcp_lib_evts_get_info sport "$client_evts" $SUB_ESTABLISHED)
 
 	# DESTROY_SUBFLOW6 from client to server machine
 	:>"$client_evts"
@@ -819,9 +797,9 @@ test_subflows()
 			      "10.0.2.2" "10.0.2.1" "$new4_port" "23" "$server_addr_id" "ns2" "ns1"
 
 	# Delete the listener from the server ns, if one was created
-	kill_wait $listener_pid
+	mptcp_lib_kill_wait $listener_pid
 
-	sport=$(sed --unbuffered -n 's/.*\(sport:\)\([[:digit:]]*\).*$/\2/p;q' "$client_evts")
+	sport=$(mptcp_lib_evts_get_info sport "$client_evts" $SUB_ESTABLISHED)
 
 	# DESTROY_SUBFLOW from client to server machine
 	:>"$client_evts"
@@ -865,9 +843,9 @@ test_subflows_v4_v6_mix()
 			      "$server_addr_id" "ns2" "ns1"
 
 	# Delete the listener from the server ns, if one was created
-	kill_wait $listener_pid
+	mptcp_lib_kill_wait $listener_pid
 
-	sport=$(sed --unbuffered -n 's/.*\(sport:\)\([[:digit:]]*\).*$/\2/p;q' "$client_evts")
+	sport=$(mptcp_lib_evts_get_info sport "$client_evts" $SUB_ESTABLISHED)
 
 	# DESTROY_SUBFLOW from client to server machine
 	:>"$client_evts"
@@ -896,9 +874,10 @@ test_prio()
 
 	# Check TX
 	print_test "MP_PRIO TX"
-	count=$(ip netns exec "$ns2" nstat -as | grep MPTcpExtMPPrioTx | awk '{print $2}')
-	[ -z "$count" ] && count=0
-	if [ $count != 1 ]; then
+	count=$(mptcp_lib_get_counter "$ns2" "MPTcpExtMPPrioTx")
+	if [ -z "$count" ]; then
+		test_skip
+	elif [ $count != 1 ]; then
 		test_fail "Count != 1: ${count}"
 	else
 		test_pass
@@ -906,9 +885,10 @@ test_prio()
 
 	# Check RX
 	print_test "MP_PRIO RX"
-	count=$(ip netns exec "$ns1" nstat -as | grep MPTcpExtMPPrioRx | awk '{print $2}')
-	[ -z "$count" ] && count=0
-	if [ $count != 1 ]; then
+	count=$(mptcp_lib_get_counter "$ns1" "MPTcpExtMPPrioRx")
+	if [ -z "$count" ]; then
+		test_skip
+	elif [ $count != 1 ]; then
 		test_fail "Count != 1: ${count}"
 	else
 		test_pass
@@ -933,18 +913,13 @@ verify_listener_events()
 		print_test "CLOSE_LISTENER $e_saddr:$e_sport"
 	fi
 
-	type=$(grep "type:$e_type," $evt |
-	       sed --unbuffered -n 's/.*\(type:\)\([[:digit:]]*\).*$/\2/p;q')
-	family=$(grep "type:$e_type," $evt |
-		 sed --unbuffered -n 's/.*\(family:\)\([[:digit:]]*\).*$/\2/p;q')
-	sport=$(grep "type:$e_type," $evt |
-		sed --unbuffered -n 's/.*\(sport:\)\([[:digit:]]*\).*$/\2/p;q')
+	type=$(mptcp_lib_evts_get_info type $evt $e_type)
+	family=$(mptcp_lib_evts_get_info family $evt $e_type)
+	sport=$(mptcp_lib_evts_get_info sport $evt $e_type)
 	if [ $family ] && [ $family = $AF_INET6 ]; then
-		saddr=$(grep "type:$e_type," $evt |
-			sed --unbuffered -n 's/.*\(saddr6:\)\([0-9a-f:.]*\).*$/\2/p;q')
+		saddr=$(mptcp_lib_evts_get_info saddr6 $evt $e_type)
 	else
-		saddr=$(grep "type:$e_type," $evt |
-			sed --unbuffered -n 's/.*\(saddr4:\)\([0-9.]*\).*$/\2/p;q')
+		saddr=$(mptcp_lib_evts_get_info saddr4 $evt $e_type)
 	fi
 
 	check_expected "type" "family" "saddr" "sport"
@@ -982,7 +957,7 @@ test_listener()
 	sleep 0.5
 
 	# Delete the listener from the client ns, if one was created
-	kill_wait $listener_pid
+	mptcp_lib_kill_wait $listener_pid
 
 	sleep 0.5
 	verify_listener_events $client_evts $LISTENER_CLOSED $AF_INET 10.0.2.2 $client4_port