diff --git a/tools/testing/selftests/net/mptcp/mptcp_join.sh b/tools/testing/selftests/net/mptcp/mptcp_join.sh
index 00cf4efac4c2..1e1c3d713360 100755
--- a/tools/testing/selftests/net/mptcp/mptcp_join.sh
+++ b/tools/testing/selftests/net/mptcp/mptcp_join.sh
@@ -1740,7 +1740,10 @@ chk_rm_nr()
 		# in case of simult flush, the subflow removal count on each side is
 		# unreliable
 		count=$((count + cnt))
-		[ "$count" != "$rm_subflow_nr" ] && suffix="$count in [$rm_subflow_nr:$((rm_subflow_nr*2))]"
+		if [ "$count" != "$rm_subflow_nr" ]; then
+			suffix="$count in [$rm_subflow_nr:$((rm_subflow_nr*2))]"
+			extra_msg="$extra_msg simult"
+		fi
 		if [ $count -ge "$rm_subflow_nr" ] && \
 		   [ "$count" -le "$((rm_subflow_nr *2 ))" ]; then
 			print_ok "$suffix"