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Date: Mon, 21 Jul 2014 12:22:59 -0700
Message-ID: <CADoY-6j0d9pBn-TDoMf5gysE8QiGz42DCFGLDWASig-wqLiMbg@mail.gmail.com>
Subject: Remote kernel debugging question
From: Nidal Khalil <nedmath@gmail.com>
To: freebsd-hackers@freebsd.org
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Hello All,
I am somewhat new to BSD kernel but I am trying to debug a kernel module
using remote debugging.
I am using 9.2 RELEASE.
I setup and compiled the kernel with the following:

makeoptions DEBUG=-g
options          KDB
options          KDB_TRACE
options          DDB_CTF
options          DDB
options          GDB
options          ALT_BREAK_TO_DEBUGGER

I setup the uart for serial1 flags to 0x90 and I can read and write to the
serial from either machine
Both machines have the same kernel booted.
I can enter ddb but I can not launch gdb
The remote GDB backend could not be selected.
sysctl -a | grep debug.kdb

debug.kdb.available: ddb
Is that correct or it should be:
debug.kdb.available: ddb gdb
How do I enable gdb backend. I appreciate the help.

Nidal