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Date: Sat, 9 Nov 2013 20:05:47 +0200
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Subject: ARM kgdb remote debugging over USB serial
From: Boris Astardzhiev <boris.astardzhiev@gmail.com>
To: freebsd-arm@freebsd.org, freebsd-hackers@freebsd.org
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Hi,

I have a question regarding the FreeBSD kernel debugging facilities.
Has anyone succeeded in using kgdb with a target ARM machine over a USB
serial.
I've managed to build kgdb-arm

http://bsdimp.blogspot.com/2007/10/cross-debugger.html
(This tutorial also applies to building kgdb-arm in binutils)

So on the arm machine I enter kdb:
db> gdb
db> s
..

On the debugging machine I easily get into kgdb:
kgdb-arm ${KERNEL_PATH}/kernel.debug
kgdb> set remotebaud 115200
kgdb> target remote /dev/cuaU0 (the USB interface)

So far so good but.. It seems to connect to the ARM device but it stops on
an address kgdb has no
reference about. I thought I was missing some symbols and..
kgdb> set solib-search-path ${KERNEL_PATH}

This seems to load lots of symbols but still I can't backtrace or do
anything. Attempting to do a 'bt' it tells me I got a SIGTRAP. I don't seem
to understand.

Any ideas or materials?

Greetings,
Boris