The BattOr benchmarks on the new N5X Android bots are all failing. The reason is the Linux user account does not have permission to use the serial device. Assuming the OS running on the bot is Ubuntu, the Telemetry user needs to be added to the "dialout" group. Users in this group can access serial devices without superuser credentials.

This is the error that they are failing with:

Traceback (most recent call last):
  File "/b/rr/tmpGnHCB0/w/src/third_party/catapult/telemetry/telemetry/internal/story_runner.py", line 77, in _RunStoryAndProcessErrorIfNeeded
    test.WillRunStory(state.platform)
  File "/b/rr/tmpGnHCB0/w/src/third_party/catapult/telemetry/telemetry/web_perf/timeline_based_measurement.py", line 276, in WillRunStory
    platform.tracing_controller.StartTracing(self._tbm_options.config)
  File "/b/rr/tmpGnHCB0/w/src/third_party/catapult/telemetry/telemetry/core/tracing_controller.py", line 43, in StartTracing
    self._tracing_controller_backend.StartTracing(tracing_config, timeout)
  File "/b/rr/tmpGnHCB0/w/src/third_party/catapult/telemetry/telemetry/internal/platform/tracing_controller_backend.py", line 91, in StartTracing
    if agent.StartAgentTracing(config, timeout):
  File "/b/rr/tmpGnHCB0/w/src/third_party/catapult/telemetry/telemetry/internal/platform/tracing_agent/battor_tracing_agent.py", line 71, in StartAgentTracing
    self._battor.StartTracing()
  File "/b/rr/tmpGnHCB0/w/src/third_party/catapult/common/battor/battor/battor_wrapper.py", line 129, in StartTracing
    self._SendBattorCommand(self._START_TRACING_CMD)
  File "/b/rr/tmpGnHCB0/w/src/third_party/catapult/common/battor/battor/battor_wrapper.py", line 226, in _SendBattorCommand
    'Outputted: %s' % (cmd, status))
BattorError: BattOr did not complete command 'StartTracing' correctly.
Outputted: [0726/185610:ERROR:serial_io_handler.cc(168)] Failed to open serial port: FILE_ERROR_ACCESS_DENIED