Re: Running Xorg with a serial console

[Valery Ushakov <uwe%stderr.spb.ru@localhost>]

On Sun, Sep 29, 2024 at 23:50:01 +0000, Emmanuel Dreyfus wrote:

> I try to run Xorg on an amd64 machine with a serial console. On NetBSD 
> 10.0, it badly fails for two reasons.
> 
> First, Xorg probes the console driver and considers a failure as 
> fatal. When running on a serial console, wscons is not initialized,
> and Xorg will not start. The patch below fixes that.
> 
> This first bug being addressed, the machine will experrience several
> freeze while Xorg start, The console display pckbport: command timeout
> This comes from pckbport_cleanup() in src/sys/dev/pckbport/pckbport.c
> 
> DDB tells me I come there trhough: that code paths: 
> wsmouseopen/pms_enable/do_enable/pckbportprint
> wsmouseclose/pms_disable/do_disabke/pckbportprint
> wsmuxopen/pms_enable/do_enable/pckbportprint
> wsmuxclose/wsmouse_mux_close/pms_disable/do_disable/pckbportprint
> 
> I understand this happens because the kernel configured this:
> wsmouse0 at pms0 mux 0
> 
> And ineed, booting with "userconf disable pckbc0" works around the problem.
> I wonder if we could not handle that more gracefully. Would it make sense
> to check that wasons was not configured, so that we can quickly fail 
> wsmouse/wsmux open operation?

It's not clear what you configureation is and what you are trying to
do.  What do you mean by "wscons is not initialized"?

You can run NetBSD with serial console and with wscons on the
"graphical" side of things.  I used to force serial console on my
sparc javastation and I could still run X on the screen/keyboard/mouse
"console".  On i386 you can use serial console for DDB to debug
graphics problems and the wscons is initialized even though you use
serial console.

-uwe