File	Date	Author	Commit
Makefile	2011-02-24	Bin Yang	[fd7e2e] socket kgdb alpha release
README	2011-02-24	Bin Yang	[fd7e2e] socket kgdb alpha release
fsock_fw.c	2011-02-24	Bin Yang	[fd7e2e] socket kgdb alpha release
gdb_serial_protocol.html	2011-02-14	Bin Yang	[20e56c] socket kgdb rc1
gdbstub.c	2011-02-24	Bin Yang	[fd7e2e] socket kgdb alpha release
run.sh	2011-02-24	Bin Yang	[fd7e2e] socket kgdb alpha release
skgdb.c	2011-02-24	Bin Yang	[fd7e2e] socket kgdb alpha release
skgdb.h	2011-02-24	Bin Yang	[fd7e2e] socket kgdb alpha release
skgdb_start.sh	2011-02-24	Bin Yang	[fd7e2e] socket kgdb alpha release
tty.c	2011-02-24	Bin Yang	[fd7e2e] socket kgdb alpha release
x86_32.c	2011-02-24	Bin Yang	[fd7e2e] socket kgdb alpha release

Read Me

The code is ugly. And I believe lots of potential bugs inside.
Only X86 32 is supported. easy to add other arch support.

The purpose of this tool:
1. debug kernel without any HW support.
2. debug specific thread without stop kernel.
it helps to debug in realtime requirment system.
3. If you enjoy it, please share your happy with me. :)

The limitations,
1. can not break inside atomic context.
2. can not support 'n' and 's' commands in gdb

Here is the theory.
1. enable kprobe
2. hack the kprobe. including the die notify priority, ins boundary
checking, jump optimizing.
3. add kprobe at break instruction.
4. hack the kprobe die notification priority. Add a hack function before
int 3 die notification. The hack function save the pt_regs and hack
the return ip register to gdb stub server fuction.
4. after gdb stub server return, hack the return ip and jump back to
kprobe function.
All hack functions use "kallsyms_lookup_name" to find the address and modify the
original value dynamically.

Steps to try it:
1. enable kprobe in your kernel config
2. modify Makefile base on your kernel src code patch.
3. make it. Copy skgdb_start.sh socket_kgdb.ko fsock_fw to your board.
3. run skgdb_start.sh.
5. connect gdb: target remote yourip:7321

Bin Yang <byang1217@gmail.com>
Bin Yang <bin.yang@intel.com>