Comment 2 for bug 2014953

This is in:

def get_max_lanes(port):
    """
    Get the $port's maximum number of lanes.
    Return: number of lanes, e.g. 1, 2, 4 and 8.
    """

    cmd = "devlink -j port show %s" % port
    stdout, stderr = run_command(cmd)
    assert stderr == ""
    values = list(json.loads(stdout)['port'].values())[0]

We're expecting stderr to be empty, but since this command triggers a warning / error, the `assert stderr == ""` fails.

This issue does not exist with 6.5.0-4-generic (on node riccioli, it's failing with L-ibm)