kgdb on NetBSD/amd64 6.99.23

[Jan Danielsson <jan.m.danielsson%gmail.com@localhost>]

Hello,

   I'm trying to get kgdb working between two virtual box instances. (I
have verified that /dev/tty00 <-> /dev/tty00 works by running GENERIC
kernels and minicom on both virtual machines).

   I basically did what is documented on:
http://www.netbsd.org/docs/kernel/kgdb.html

  The webpage says that I can boot using "boot -d" which should make the
kernel stop and wait for a debugger to attach, but "boot -d" doesn't
appear to do anything -- it just boots normally.

   The kernel configuration does not have "options DDB" and doesn't have
"options DDB_HISTORY_SIZE". But it does have:

options KGDB
options "KGDB_DEVNAME=\"com\"",KGDB_DEVADDR=0x3f8,KGDB_DEVRATE=115200
makeoptions DEBUG="-g"

   On the "target":
   $ dmesg | grep com0
   com0 at isa0 port 0x3f8-0x3ff irq 4: ns16550a, working fifo
   com0: kgdb

   The "remote" system has, in /etc/ttys:
   tty00 "/usr/libexec/getty std.115200" unknown off local

   And on the same system I run (in gdb):
   file netbsd.gdb
   set remotebreak 1
   set remotebaud 115200
   target remote /dev/tty00

   gdb hangs for a while, then outputs:
   Ignoring packet error, continuing...
   Warning: unrecognized item "timeout" in "qSupported" response
   Ignoring packet error, continuing...
   Ignoring packet error, continuing...
   Ignoring packet error, continuing...
   [---]

   And after a few repeats it gives up.

   I know (through the minicom-test) that there's no problem with the
actual serial communication. The fact that "boot -d" doesn't do anything
made me think that the kgdb support wasn't being built, but then again
the dmesg output does list "com0: kgdb".

   Help?

   /Jan