According to the Python documentation the preexec_fn argument is not
thread-safe and can cause a deadlock in the child process.
The use of preexec_fn=os.setsid can be avoided by using
start_new_session=True in the popen() call which is available in Python
>= 3.2
DEBUG zuul.stack_dump: Thread: 139775071643392 build-e584032fcc424259be5b0feddfc3f0b4 d: True
File "/usr/lib/python3.6/threading.py", line 884, in _bootstrap
self._bootstrap_inner()
File "/usr/lib/python3.6/threading.py", line 916, in _bootstrap_inner
self.run()
File "/usr/lib/python3.6/threading.py", line 864, in run
self._target(*self._args, **self._kwargs)
File "/opt/zuul/lib/python3.6/site-packages/zuul/executor/server.py", line 931, in execute
self._execute()
File "/opt/zuul/lib/python3.6/site-packages/zuul/executor/server.py", line 1154, in _execute
result = self.runPlaybooks(args)
File "/opt/zuul/lib/python3.6/site-packages/zuul/executor/server.py", line 1437, in runPlaybooks
phase='post', index=index)
File "/opt/zuul/lib/python3.6/site-packages/zuul/executor/server.py", line 2464, in runAnsiblePlaybook
cleanup=phase == 'cleanup')
File "/opt/zuul/lib/python3.6/site-packages/zuul/executor/server.py", line 2210, in runAnsible
env=env_copy,
File "/opt/zuul/lib/python3.6/site-packages/zuul/driver/bubblewrap/__init__.py", line 55, in __call__
proc = psutil.Popen(args, *sub_args, **kwargs)
File "/opt/zuul/lib/python3.6/site-packages/psutil/__init__.py", line 1322, in __init__
self.__subproc = subprocess.Popen(*args, **kwargs)
File "/usr/lib/python3.6/subprocess.py", line 729, in __init__
restore_signals, start_new_session)
File "/usr/lib/python3.6/subprocess.py", line 1318, in _execute_child
part = os.read(errpipe_read, 50000)
Change-Id: I0b5110e0b29025f9bb121be26a678fcbe130ba73
e02963f6e1