This patch adds a selftest for userpsace PM to remove id 0 address.
Use userspace_pm_add_addr() helper to add a id 10 address, then use
userspace_pm_rm_addr() helper to remove id 0 address.

Signed-off-by: Geliang Tang <geliang.tang@suse.com>
---
 .../testing/selftests/net/mptcp/mptcp_join.sh | 24 +++++++++++++++++++
 1 file changed, 24 insertions(+)

diff --git a/tools/testing/selftests/net/mptcp/mptcp_join.sh b/tools/testing/selftests/net/mptcp/mptcp_join.sh
index f1a7e04815b1..19a6859bd207 100755
--- a/tools/testing/selftests/net/mptcp/mptcp_join.sh
+++ b/tools/testing/selftests/net/mptcp/mptcp_join.sh
@@ -3496,6 +3496,30 @@ userspace_tests()
 		kill_events_pids
 		wait $tests_pid
 	fi
+
+	# userspace pm remove id 0 address
+	if reset_with_events "userspace pm remove id 0 address" &&
+	   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=10 \
+			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_all_subflows 2 2
+		chk_mptcp_info add_addr_signal 1 add_addr_accepted 1
+		userspace_pm_rm_addr $ns1 0
+		chk_rm_nr 1 0 invert
+		chk_rst_nr 1 1 invert
+		chk_mptcp_info subflows 1 subflows 1
+		chk_all_subflows 1 1
+		kill_events_pids
+		wait $tests_pid
+	fi
 }
 
 endpoint_tests()
-- 
2.35.3