Re: kernel gdb for intel

["Amit S. Kale" <akale@veritas.com>]

Hi Brent,

You can have a look at http://kgdb.sourceforge.net/
That's where I maintain kgdb for x86.
It's many more features and lot of documentation which is
not there in sparc and ppc kgdbs.

Brent Baccala wrote:
> 
> Hi -
> 
> I've been trying to track down a problem I've had with a USB CD-Burner
> locking up.  In the course of my investigations I ported the i386 remote
> gdb stuff to the Linux kernel, because I'm used to using gdb on the
> kernel (it works on SPARC and PPC) instead of trying to read oopses.
> 
> For those not familiar with the remote debug feature, you use two
> computers, connected together with a null modem serial line.  One
> computer has a complete Linux kernel tree on it, compiled with debugging
> information (-g); the other computer is the one running the kernel under
> test.  You can breakpoint and halt the kernel, which puts it in a tight
> little loop reading packets (gdb, not IP) from the serial port and
> responding to the debugger.  You get almost all the features you're used
> to with gdb - stack backtraces, single stepping, source-based variable
> names, intelligent structure decodes, etc.
> 
> Anyway, I'm attaching the patch (against 2.4.6).  After installing, a
> menu option appears under "Kernel hacking" for remote debugging.
> Recompile the whole kernel (make clean) so that it compiles with
> debugging info.  Then supply the "kgdb" switch to the kernel command
> line, make sure the debugging computer is attached on COM1 (or whatever
> you want to call it), and run "target remote /dev/whatever" on the
> debugging computer.  See arch/i386/kernel/stub-i386.c for more info.
> 


-- 
Amit Kale
Veritas Software ( http://www.veritas.com )