Setting up a running FreeBSD/PCBSD system to enter kgdb on panic

[Garrett Cooper]

On Mon, Apr 4, 2011 at 5:26 PM, Julian Elischer <julian at freebsd.org> wrote:
> On 4/4/11 4:35 PM, David Somayajulu wrote:
>>
>> Hi All,
>> Is there some way I can setup a running FreeBSD - (I use PCBSD7.2) - to
>> break into kgdb when the system panics. I am trying to get a stack trace
>> when "Fatal trap 12: page fault while in kernel mode" happens.
>> thanks
>> david S.
>
> sure but firstly have you already got everything set up so you can get into
> kgdb normally?
> (serial cable? (or firewire?) ports all set up right? second machine?
>
> here are som bits of the puzzle for my machine:
>
> from /boot/device.hints:
>
> hint.uart.1.at="isa"
> hint.uart.1.port="0x2F8"
> hint.uart.1.flags="0x80"
> hint.uart.1.irq="3"
> hint.uart.1.baud="115200"

    .flags on uart(4) doesn't support 0x20, 0x40, like on sio(4). Interesting.
Thanks,
-Garrett