2022-03-11 06:01:14

by Vincent Whitchurch

Subject: [PATCH] docs: UML: Mention telnetd for port channel

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 <[email protected]>
---
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.

--
2.34.1

2022-03-11 23:32:17

by Jonathan Corbet

Subject: Re: [PATCH] docs: UML: Mention telnetd for port channel

Vincent Whitchurch <[email protected]> writes:

> 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 <[email protected]>
> ---
> 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.

Applied, thanks.

jon