Exit code -11 with ros_bridge

what doesn’t exit code -11 mean in ros bridge? I have been stuck in this problem for a long time and it happens in both carla 0.9.10 and 0.9.11.
Anyone can help? Thanks.

... logging to /home/omnisky/.ros/log/78215d14-8ec9-11eb-854d-0c9d92c5f85e/roslaunch-xx-13471.log
Checking log directory for disk usage. This may take a while.
Press Ctrl-C to interrupt
Done checking log file disk usage. Usage is <1GB.

started roslaunch server http://omnisky:40519/

SUMMARY
========

PARAMETERS
 * /carla_ackermann_control_ego_vehicle/accel_Kd: 0.05
 * /carla_ackermann_control_ego_vehicle/accel_Ki: 0.0
 * /carla_ackermann_control_ego_vehicle/accel_Kp: 0.02
 * /carla_ackermann_control_ego_vehicle/control_loop_rate: 0.05
 * /carla_ackermann_control_ego_vehicle/min_accel: 1.0
 * /carla_ackermann_control_ego_vehicle/role_name: ego_vehicle
 * /carla_ackermann_control_ego_vehicle/speed_Kd: 0.5
 * /carla_ackermann_control_ego_vehicle/speed_Ki: 0.0
 * /carla_ackermann_control_ego_vehicle/speed_Kp: 0.05
 * /carla_manual_control_ego_vehicle/role_name: ego_vehicle
 * /carla_ros_bridge/ego_vehicle_role_name: ["hero", "ego_veh...
 * /carla_ros_bridge/fixed_delta_seconds: 0.05
 * /carla_ros_bridge/host: localhost
 * /carla_ros_bridge/passive: False
 * /carla_ros_bridge/port: 2000
 * /carla_ros_bridge/synchronous_mode: True
 * /carla_ros_bridge/synchronous_mode_wait_for_vehicle_control_command: False
 * /carla_ros_bridge/timeout: 10
 * /carla_ros_bridge/town: Town02
 * /rosdistro: melodic
 * /rosversion: 1.14.5
 * /use_sim_time: True

NODES
  /
    carla_ackermann_control_ego_vehicle (carla_ackermann_control/carla_ackermann_control_node.py)
    carla_manual_control_ego_vehicle (carla_manual_control/carla_manual_control.py)
    carla_ros_bridge (carla_ros_bridge/bridge.py)

auto-starting new master
process[master]: started with pid [13571]
ROS_MASTER_URI=http://localhost:11311

setting /run_id to 78215d14-8ec9-11eb-854d-0c9d92c5f85e
process[rosout-1]: started with pid [13582]
started core service [/rosout]
process[carla_ros_bridge-2]: started with pid [13589]
process[carla_ackermann_control_ego_vehicle-3]: started with pid [13590]
process[carla_manual_control_ego_vehicle-4]: started with pid [13591]
pygame 2.0.1 (SDL 2.0.14, Python 3.6.9)
Hello from the pygame community. https://www.pygame.org/contribute.html
[INFO] [1616828153.528670, 0.000000]: Reconfigure Request:  speed (0.05, 0.0, 0.5), accel (0.02, 0.0, 0.05)
[INFO] [1616828154.496502, 0.000000]: Trying to connect to localhost:2000
[INFO] [1616828154.670287, 0.000000]: synchronous_mode: True
[INFO] [1616828154.672149, 0.000000]: fixed_delta_seconds: 0.05
[INFO] [1616828154.775988, 0.000000]: Parameters:
[INFO] [1616828154.777978, 0.000000]:   host: localhost
[INFO] [1616828154.779346, 0.000000]:   port: 2000
[INFO] [1616828154.780417, 0.000000]:   timeout: 10
[INFO] [1616828154.781388, 0.000000]:   passive: False
[INFO] [1616828154.782320, 0.000000]:   synchronous_mode: True
[INFO] [1616828154.783256, 0.000000]:   synchronous_mode_wait_for_vehicle_control_command: False
[INFO] [1616828154.784206, 0.000000]:   fixed_delta_seconds: 0.05
[INFO] [1616828154.785124, 0.000000]:   town: Town02
[INFO] [1616828154.786065, 0.000000]:   ego_vehicle: {'role_name': '["hero", "ego_vehicle", "hero0", "hero1", "hero2", "hero3", "hero4", "hero5", "hero6", "hero7", "hero8", "hero9"]'}
[INFO] [1616828154.902752, 137.925848]: Created Spectator(id=1099)
[INFO] [1616828154.904399, 137.925848]: Created TrafficLight(id=1100)
[INFO] [1616828154.905566, 137.925848]: Created TrafficLight(id=1101)
[INFO] [1616828154.906674, 137.925848]: Created TrafficLight(id=1102)
[INFO] [1616828154.907738, 137.925848]: Created TrafficLight(id=1103)
[INFO] [1616828154.908803, 137.925848]: Created TrafficLight(id=1104)
[INFO] [1616828154.910147, 137.925848]: Created TrafficLight(id=1105)
[INFO] [1616828154.911204, 137.925848]: Created TrafficLight(id=1106)
[INFO] [1616828154.912417, 137.925848]: Created TrafficLight(id=1107)
[INFO] [1616828154.913483, 137.925848]: Created TrafficLight(id=1108)
[INFO] [1616828154.915473, 137.925848]: Created TrafficLight(id=1109)
[INFO] [1616828154.916641, 137.925848]: Created TrafficLight(id=1110)
[INFO] [1616828154.917741, 137.925848]: Created TrafficLight(id=1111)
[INFO] [1616828154.918872, 137.925848]: Created TrafficLight(id=1112)
[INFO] [1616828154.920155, 137.925848]: Created TrafficLight(id=1113)
[INFO] [1616828154.921415, 137.925848]: Created TrafficLight(id=1114)
[INFO] [1616828154.922681, 137.925848]: Created TrafficLight(id=1115)
[INFO] [1616828154.923962, 137.925848]: Created TrafficLight(id=1116)
[INFO] [1616828154.925229, 137.925848]: Created TrafficLight(id=1117)
[INFO] [1616828154.926719, 137.925848]: Created TrafficLight(id=1118)
[INFO] [1616828154.928011, 137.925848]: Created TrafficLight(id=1119)
[INFO] [1616828154.929496, 137.925848]: Created TrafficLight(id=1120)
[INFO] [1616828154.930882, 137.925848]: Created TrafficLight(id=1121)
[INFO] [1616828154.932583, 137.925848]: Created TrafficLight(id=1122)
[INFO] [1616828154.933958, 137.925848]: Created TrafficLight(id=1123)
[INFO] [1616828154.935331, 137.925848]: Created Traffic(id=1124)
[INFO] [1616828154.936699, 137.925848]: Created Traffic(id=1125)
[INFO] [1616828154.938066, 137.925848]: Created Traffic(id=1126)
[INFO] [1616828154.939481, 137.925848]: Created Traffic(id=1127)
[INFO] [1616828154.940882, 137.925848]: Created Traffic(id=1128)
[INFO] [1616828154.942286, 137.925848]: Created Traffic(id=1129)
[INFO] [1616828154.943852, 137.925848]: Created Traffic(id=1130)
[INFO] [1616828154.945255, 137.925848]: Created Traffic(id=1131)
[INFO] [1616828154.946684, 137.925848]: Created Traffic(id=1132)
[INFO] [1616828154.948086, 137.925848]: Created Traffic(id=1133)
[INFO] [1616828154.949503, 137.925848]: Created Traffic(id=1134)
[INFO] [1616828154.950910, 137.925848]: Created Traffic(id=1135)
[INFO] [1616828154.952352, 137.925848]: Created Traffic(id=1136)
[INFO] [1616828154.953776, 137.925848]: Created Traffic(id=1137)
[INFO] [1616828154.955178, 137.925848]: Created Traffic(id=1138)
[INFO] [1616828154.956597, 137.925848]: Created Traffic(id=1139)
[INFO] [1616828154.958045, 137.925848]: Created Traffic(id=1140)
[INFO] [1616828154.959493, 137.925848]: Created Traffic(id=1141)
[INFO] [1616828154.960915, 137.925848]: Created Traffic(id=1142)
[INFO] [1616828154.962642, 137.925848]: Created Traffic(id=1143)
[INFO] [1616828154.964593, 137.925848]: Created Traffic(id=1144)
[INFO] [1616828154.966097, 137.925848]: Created Actor(id=1145)
[INFO] [1616828154.967563, 137.925848]: Created Actor(id=1146)
[INFO] [1616828154.969012, 137.925848]: Created Actor(id=1147)
[INFO] [1616828154.970463, 137.925848]: Created Actor(id=1148)
[INFO] [1616828154.971914, 137.925848]: Created Actor(id=1149)
[INFO] [1616828154.973381, 137.925848]: Created Actor(id=1150)
[INFO] [1616828154.974828, 137.925848]: Created Actor(id=1151)
[INFO] [1616828154.976290, 137.925848]: Created Actor(id=1152)
[INFO] [1616828154.977768, 137.925848]: Created Actor(id=1153)
[INFO] [1616828154.979795, 137.925848]: Created Actor(id=1154)
[INFO] [1616828154.981256, 137.925848]: Created Actor(id=1155)
[INFO] [1616828154.982701, 137.925848]: Created Actor(id=1156)
[INFO] [1616828154.984391, 137.925848]: Created Actor(id=1157)
[INFO] [1616828154.985847, 137.925848]: Created Actor(id=1158)
[INFO] [1616828154.987290, 137.925848]: Created Actor(id=1159)
[INFO] [1616828154.988741, 137.925848]: Created Actor(id=1160)
[INFO] [1616828154.990189, 137.925848]: Created Actor(id=1161)
[INFO] [1616828154.991649, 137.925848]: Created Actor(id=1162)
[INFO] [1616828154.993092, 137.925848]: Created Actor(id=1163)
[INFO] [1616828154.996054, 137.925848]: Created Actor(id=1164)
[INFO] [1616828154.997715, 137.925848]: Created Actor(id=1165)
[INFO] [1616828154.999154, 137.925848]: Created Actor(id=1166)
[INFO] [1616828155.000708, 137.925848]: Created Actor(id=1167)
[INFO] [1616828155.002269, 137.925848]: Created Actor(id=1168)
[INFO] [1616828155.003882, 137.925848]: Created Actor(id=1169)
[INFO] [1616828155.005440, 137.925848]: Created Actor(id=1170)
[INFO] [1616828155.006995, 137.925848]: Created Actor(id=1171)
[INFO] [1616828155.008581, 137.925848]: Created Actor(id=1172)
[INFO] [1616828155.010226, 137.925848]: Created Actor(id=1173)
[INFO] [1616828155.011911, 137.925848]: Created Actor(id=1174)
[INFO] [1616828155.013535, 137.925848]: Created Actor(id=1175)
[INFO] [1616828155.015113, 137.925848]: Created Actor(id=1176)
[INFO] [1616828155.016683, 137.925848]: Created Actor(id=1177)
[INFO] [1616828155.018242, 137.925848]: Created Actor(id=1178)
[INFO] [1616828155.019888, 137.925848]: Created Actor(id=1179)
[INFO] [1616828155.021423, 137.925848]: Created Actor(id=1180)
[INFO] [1616828155.022932, 137.925848]: Created Actor(id=1181)
[INFO] [1616828155.024472, 137.925848]: Created Actor(id=1182)
[INFO] [1616828155.026044, 137.925848]: Created Actor(id=1183)
[INFO] [1616828155.027920, 137.925848]: Created Actor(id=1184)
[INFO] [1616828155.029459, 137.925848]: Created Actor(id=1185)
[INFO] [1616828155.030938, 137.925848]: Created Actor(id=1186)
[INFO] [1616828155.032475, 137.925848]: Created Actor(id=1187)
[INFO] [1616828155.033934, 137.925848]: Created Actor(id=1188)
[INFO] [1616828155.035387, 137.925848]: Created Actor(id=1189)
[INFO] [1616828155.036839, 137.925848]: Created Actor(id=1190)
[INFO] [1616828155.038294, 137.925848]: Created Actor(id=1191)
[INFO] [1616828155.039754, 137.925848]: Created Actor(id=1192)
[INFO] [1616828155.041200, 137.925848]: Created Actor(id=1193)
[INFO] [1616828155.042643, 137.925848]: Created Actor(id=1194)
[INFO] [1616828155.044099, 137.925848]: Created Actor(id=1195)
[INFO] [1616828155.045544, 137.925848]: Created Actor(id=1196)
[INFO] [1616828155.046988, 137.925848]: Created Actor(id=1197)
[INFO] [1616828155.048451, 137.925848]: Created Actor(id=1198)
[INFO] [1616828155.049896, 137.925848]: Created Actor(id=1199)
[INFO] [1616828155.051353, 137.925848]: Created Actor(id=1200)
[INFO] [1616828155.052821, 137.925848]: Created Actor(id=1201)
[INFO] [1616828155.054286, 137.925848]: Created Actor(id=1202)
[INFO] [1616828155.055744, 137.925848]: Created Actor(id=1203)
[INFO] [1616828155.057184, 137.925848]: Created Actor(id=1204)
[INFO] [1616828155.058625, 137.925848]: Created Actor(id=1205)
[INFO] [1616828155.060083, 137.925848]: Created Actor(id=1206)
[INFO] [1616828155.061531, 137.925848]: Created Actor(id=1207)
[INFO] [1616828155.062975, 137.925848]: Created Actor(id=1208)
[INFO] [1616828155.064436, 137.925848]: Created Actor(id=1209)
[INFO] [1616828155.065885, 137.925848]: Created Actor(id=1210)
[INFO] [1616828155.067419, 137.925848]: Created Actor(id=1211)
[INFO] [1616828155.068997, 137.925848]: Created Actor(id=1212)
[INFO] [1616828155.070467, 137.925848]: Created Actor(id=1213)
[INFO] [1616828155.071929, 137.925848]: Created Actor(id=1214)
[INFO] [1616828155.073380, 137.925848]: Created Actor(id=1215)
[INFO] [1616828155.074824, 137.925848]: Created Actor(id=1216)
[INFO] [1616828155.076273, 137.925848]: Created Actor(id=1217)
[INFO] [1616828155.077711, 137.925848]: Created Actor(id=1218)
[INFO] [1616828155.094380, 137.925848]: Created EgoVehicle(id=1219)
[INFO] [1616828155.108300, 137.925848]: Created RgbCamera(id=1220)
[INFO] [1616828155.115833, 137.925848]: Created RgbCamera(id=1221)
[INFO] [1616828155.120167, 137.925848]: Created Lidar(id=1222)
[INFO] [1616828155.125300, 137.925848]: Created Gnss(id=1223)
[INFO] [1616828155.128734, 137.925848]: Created ImuSensor(id=1224)
[INFO] [1616828155.132336, 137.925848]: Created CollisionSensor(id=1225)
================================================================================REQUIRED process [carla_ros_bridge-2] has died!
process has died [pid 13589, exit code -11, cmd /home/omnisky/catkin_ws/src/ros-bridge/carla_ros_bridge/src/carla_ros_bridge/bridge.py __name:=carla_ros_bridge __log:=/home/omnisky/.ros/log/78215d14-8ec9-11eb-854d-0c9d92c5f85e/carla_ros_bridge-2.log].
log file: /home/omnisky/.ros/log/78215d14-8ec9-11eb-854d-0c9d92c5f85e/carla_ros_bridge-2*.log
Initiating shutdown!
================================================================================
[carla_manual_control_ego_vehicle-4] killing on exit
[carla_ackermann_control_ego_vehicle-3] killing on exit
[carla_ros_bridge-2] killing on exit
[rosout-1] killing on exit
[master] killing on exit
shutting down processing monitor...
... shutting down processing monitor complete