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Subject: Re: [PATCH] docs: UML: Mention telnetd for port channel
To:     Vincent Whitchurch <vincent.whitchurch@axis.com>,
        Jeff Dike <jdike@addtoit.com>,
        Richard Weinberger <richard@nod.at>,
        Jonathan Corbet <corbet@lwn.net>
Cc:     kernel@axis.com, linux-um@lists.infradead.org,
        linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org
References: <20220310124230.3069354-1-vincent.whitchurch@axis.com>
From:   Anton Ivanov <anton.ivanov@cambridgegreys.com>
Message-ID: <e1709d07-6217-90b9-273a-50b32798da55@cambridgegreys.com>
Date:   Thu, 10 Mar 2022 14:17:19 +0000
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On 10/03/2022 12:42, Vincent Whitchurch wrote:
> 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>
> ---
>   Documentation/virt/uml/user_mode_linux_howto_v2.rst | 6 +++++-
>   1 file changed, 5 insertions(+), 1 deletion(-)
> 
> diff --git a/Documentation/virt/uml/user_mode_linux_howto_v2.rst b/Documentation/virt/uml/user_mode_linux_howto_v2.rst
> index 2cafd3c3c6cb..d5ad96c795f6 100644
> --- a/Documentation/virt/uml/user_mode_linux_howto_v2.rst
> +++ b/Documentation/virt/uml/user_mode_linux_howto_v2.rst
> @@ -664,7 +664,11 @@ one is input, the second one output.
>   * The fd channel - use file descriptor numbers for input/output. Example:
>     ``con1=fd:0,fd:1.``
>   
> -* The port channel - listen on TCP port number. Example: ``con1=port:4321``
> +* The port channel - start a telnet server on TCP port number. Example:
> +  ``con1=port:4321``.  The host must have /usr/sbin/in.telnetd (usually part of
> +  a telnetd package) and the port-helper from the UML utilities (see the
> +  information for the xterm channel below).  UML will not boot until a client
> +  connects.
>   
>   * The pty and pts channels - use system pty/pts.
>   
> 

Acked-by: Anton Ivanov <anton.ivanov@cambridgegreys.com>

-- 
Anton R. Ivanov
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