2017-10-07 00:43:04,120 FAILED: Some tests failed
  adding: reports/ (stored 0%)
  adding: reports/index.html (deflated 22%)
  adding: c_linux_ubsan_native/sponge_log.xml (deflated 87%)
+ DOCKER_EXIT_CODE=2
++ mktemp
+ TEMP_REPORTS_ZIP=/tmp/tmp.V5MdPp8zdq
+ docker cp run_tests_ee82fa35-9f64-4d5c-8264-4b6f17e0c2d5:/var/local/git/grpc/reports.zip /tmp/tmp.V5MdPp8zdq
+ unzip -o /tmp/tmp.V5MdPp8zdq -d /tmpfs/src/github/grpc
Archive:  /tmp/tmp.V5MdPp8zdq
  inflating: /tmpfs/src/github/grpc/reports/index.html  
  inflating: /tmpfs/src/github/grpc/c_linux_ubsan_native/sponge_log.xml  
+ rm -f /tmp/tmp.V5MdPp8zdq
+ docker rm -f run_tests_ee82fa35-9f64-4d5c-8264-4b6f17e0c2d5
run_tests_ee82fa35-9f64-4d5c-8264-4b6f17e0c2d5
+ exit 2
Traceback (most recent call last):
  File "tools/run_tests/run_tests.py", line 1448, in <module>
    env=env)
  File "/usr/lib/python2.7/subprocess.py", line 186, in check_call
    raise CalledProcessError(retcode, cmd)
subprocess.CalledProcessError: Command 'tools/run_tests/dockerize/build_docker_and_run_tests.sh' returned non-zero exit status 2