portmap can fail due to the call to xprt_close() in xprt_connect():
    xprt_disconnect() wakes up xprt->snd_task, and sets -ENOTCONN,
    which again gets converted to EIO by xprt_connect_status()

  Fix is to remove call to xprt_disconnect(). We don't need it in the
  case when we are reconnecting. However we do need to ensure that we
  wake up xprt->snd_task if reconnection fails.

  Diagnosis & proposed solution by Olaf Kirch