It is not obvious from the documentation that using the "port" channel for the console requires telnetd to be installed (see port_connection() in arch/um/drivers/port_user.c). Mention this, and the fact that UML will not boot until a client connects. Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com> Acked-by: Anton Ivanov <anton.ivanov@cambridgegreys.com> Link: https://lore.kernel.org/r/20220310124230.3069354-1-vincent.whitchurch@axis.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>