salt minion error on debian arm

salt-minion

salt-minion -l all
[DEBUG   ] Reading configuration from /etc/salt/minion
[DEBUG   ] Guessing ID. The id can be explicitly in set /etc/salt/minion
[INFO    ] Found minion id from getfqdn(): freedombox
[INFO    ] Configuration file path: /etc/salt/minion
[INFO    ] Setting up the Salt Minion "freedombox"
[DEBUG   ] Created pidfile: /var/run/salt-minion.pid
[DEBUG   ] Chowned pidfile: /var/run/salt-minion.pid to user: root
[DEBUG   ] Reading configuration from /etc/salt/minion
[DEBUG   ] loading grain in ['/var/cache/salt/minion/extmods/grains', '/usr/lib/python2.7/dist-packages/salt/grains']
[DEBUG   ] Skipping /var/cache/salt/minion/extmods/grains, it is not a directory
[TRACE   ] Added core.append_domain to grain
[TRACE   ] Added core.get_master to grain
[TRACE   ] Added core.get_server_id to grain
[TRACE   ] Added core.hostname to grain
[TRACE   ] Added core.id_ to grain
[TRACE   ] Added core.ip4 to grain
[TRACE   ] Added core.locale_info to grain
[TRACE   ] Added core.os_data to grain
[TRACE   ] Added core.path to grain
[TRACE   ] Added core.pythonpath to grain
[TRACE   ] Added core.pythonversion to grain
[TRACE   ] Added core.saltpath to grain
[TRACE   ] Added core.saltversion to grain
[TRACE   ] Added opts.opts to grain
[TRACE   ] Added extra.config to grain
[TRACE   ] Added extra.shell to grain
[DEBUG   ] Attempting to authenticate with the Salt Master at 192.168.1.86
[DEBUG   ] Loaded minion key: /etc/salt/pki/minion/minion.pem
Traceback (most recent call last):
  File "/usr/bin/salt-minion", line 14, in <module>
    salt_minion()
  File "/usr/lib/python2.7/dist-packages/salt/scripts.py", line 29, in salt_minion
    minion.start()
  File "/usr/lib/python2.7/dist-packages/salt/__init__.py", line 195, in start
    self.prepare()
  File "/usr/lib/python2.7/dist-packages/salt/__init__.py", line 183, in prepare
    self.minion = salt.minion.Minion(self.config)
  File "/usr/lib/python2.7/dist-packages/salt/minion.py", line 238, in __init__
    self.authenticate()
  File "/usr/lib/python2.7/dist-packages/salt/minion.py", line 644, in authenticate
    creds = auth.sign_in()
  File "/usr/lib/python2.7/dist-packages/salt/crypt.py", line 263, in sign_in
    if 'load' in payload:
TypeError: argument of type 'NoneType' is not iterable