port-vax/59150: entering ddb on VAX does not work as advertized

[martin%NetBSD.org@localhost]

>Number:         59150
>Category:       port-vax
>Synopsis:       entering ddb on VAX does not work as advertized
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    port-vax-maintainer
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Thu Mar 06 16:00:00 +0000 2025
>Originator:     Martin Husemann
>Release:        NetBSD 10.99.10
>Organization:
The NetBSD Foundation, Inc.
>Environment:
System: NetBSD dead-to-the-world.duskware.de 10.99.10 NetBSD 10.99.10 (DEAD) #21: Mon Feb 26 18:40:50 CET 2024 martin%seven-days-to-the-wolves.aprisoft.de@localhost:/work/src/sys/arch/vax/compile/DEAD vax
Architecture: vax
Machine: vax

(also happens with -current, but I need ddb to examine why my -current kernel
fails to run /etc/rc)

>Description:

The ddb(4) man page says:

ENTERING THE DEBUGGER
[..]
     ddb may also be activated from the console.  In general, sending a break
     on a serial console will activate ddb.  There are also key sequences for
     each port that will activate ddb from the keyboard:

           vax       <Esc> followed by <Shift>-D on serial console.

This would mean we have something like

	options		cnmagic="\x1bD"

in effect on VAX by default, but that does not seem to be the case and I
can't find any traces in the code that would make it so.

Adding that option manually to a kernel allows for entering ddb as described.

>How-To-Repeat:
s/a

>Fix:
n/a