Re: NULL pointer dereference panic

On Mon, Jun 19, 2006 at 06:20:54PM -0400, Andrew R. Reiter wrote:
> On Tue, 20 Jun 2006, Yar Tikhiy wrote:
> :On Tue, Jun 20, 2006 at 05:08:22AM +1000, Peter Jeremy wrote:
> :> On Mon, 2006-Jun-19 22:45:41 +0400, Yar Tikhiy wrote:
> :> >Peter, what gcc options did you build the kernel with?  My question
> :> >is unrelated to the panic, I'd just like to make stack traces look
> :> >sane in common cases :-)
> :> 
> :> In /etc/make.conf:
> :> CPUTYPE?=athlon-xp
> :> CFLAGS=-O -pipe
> :> COPTFLAGS=-O -pipe
> :
> :Indeed, gcc in athlon-xp mode handles function calls in a manner
> :different from the i386 default one.  The old backtrace would be
> :confused, too, by the code generated so.
> :
[...]
> 
> Thanks for the information regarding athlon-xp.  Have other OSes done 
> anything (special casing?) for this hardware so as to make it more easy 
> for "better" traces to be done?

I think the only reliable way of determining the number of arguments
to a function, particularly in the athlon-xp code from gcc, is to
use debugging symbols.  However, that would require loading the
full symbols along with kernel and module files.  We can leave it to
kgdb for now, it's really good at it.

-- 
Yar