kgdb expected to work?

[Jeff Rizzo <riz%tastylime.net@localhost>]

I'm doing something a little weird, so before trying to debug it (in 
specific), I wanted to see if anyone actually _uses_ kgdb successfully 
at all these days.  Note that I haven't actually used kgdb since 
dual-serial-port boxes were the norm (probably 2002 or so), so I'm quite 
rusty.

I'm running some VMs under VMWare Fusion on MacOSX - and it just 
occurred to me that I might be able to debug using kgdb under serial 
port emulation.  A couple folks gave me some pointers, and I have things 
kind-of-sort-of working in that I can attach GDB and "continue" 
execution of the kernel.

However!

when I launch the kernel (basically GENERIC with DDB removed and KGDB 
enabled at 115200) with "boot -d", I get the following on console:

kgdb waiting...fatal breakpoint trap in supervisor mode
trap type 1 code 0 eip c057224c cs 8 eflags 296 cr2 0 ilevel 8


...I can actually attach gdb at that point, which I do.  (This is a 
cross-gdb running under MacOS, built with MKCROSSGDB=yes from the same 
src tree as the kernel)

Like so:

(gdb) set remotebreak 1
(gdb) set remotebaud 115200
(gdb) target remote 127.0.0.1:12303
(gdb)

(port 12303 is where I have the emulated serial port listening via tcp).

If I type "continue", the kernel seems to run.  However, if I try to set 
a breakpoint, I get a trap on console when I would expect the breakpoint 
to hit, and gdb never returns.  I also can't seem to manually break.  I 
should also note that I get the same behavior in 5.1 and -current.

So...

Does KGDB actually still work for people?  Is there anything else anyone 
can suggest to try?  I'm not great with gdb, so it's entirely possible 
I'm doing something braindead.

Thanks!
+j