. now llc_ui_accept uses llc_ui_wait_for_data (llc_ui_recvmsg probably
  will use it too, we'll see)
. all the llc_ui_wait_for_ now receive the timeout in jiffies, not
  in seconds
. use sk_rcvtimeo()
. release_sock before going to sleep in the llc_ui_wait_for functions
. llc_ui_release has to get the socket lock