kgdb debugging

[Jeremy Chadwick]

On Wed, Oct 08, 2008 at 09:43:38PM -0700, alan yang wrote:
> thank you all, device.hints solved it!
> 
> On Tue, Oct 7, 2008 at 11:14 AM, Julian Elischer <julian at elischer.org> wrote:
> > alan yang wrote:
> >>
> >> Could people shed some light how to get remote debugging going, must
> >> be something that i overlooked, really appreciate.
> >>
> >> Two FreeBSD7 systems, target and development, connected with null
> >> modem cable on each's COM1.
> >>
> >> step 1)
> >>        -  rebuild kernel with following options:
> >>                options         DDB
> >>                options         KDB
> >>                options         GDB
> >>
> >>                makeoptions     DEBUG=-g
> >
> > add hints.dev.uart.0.flags=0xc0
> > (or whatever it is) (see man uart or man sio)
> > to /boot/device.hints

This is a bad recommendation.  *DO NOT* modify device.hints!!!

You can override device.hints entries, or add your own, by using
loader.conf.  Example, taken from our loader.conf on production
systems:

# There is no COM2 on this system.
hint.sio.1.disabled="1"

Thus, in your case, this should suffice (note "hint", not "hints"
like the above paragraph says):

hint.dev.uart.0.flags="0xc0"

-- 
| Jeremy Chadwick                                jdc at parodius.com |
| Parodius Networking                       http://www.parodius.com/ |
| UNIX Systems Administrator                  Mountain View, CA, USA |
| Making life hard for others since 1977.              PGP: 4BD6C0CB |