Re: CVS commit: src

[Andrew Doran <ad%NetBSD.org@localhost>]

On Thu, Oct 07, 2010 at 01:33:46AM +0200, Jean-Yves Migeon wrote:
> On 06.10.2010 12:16, Manuel Bouyer wrote:
> > On Tue, Oct 05, 2010 at 11:48:17PM +0000, Jean-Yves Migeon wrote:
> >> [...]
> >>
> >> XXX Currently, savecore(8) will fail to dump a PAE kernel in a !PAE
> >>     environment (and reciprocally). So you need to sync and reboot
> >>     with a kernel of the same mode as the one that crashed. Once the dump
> >>     is successful, this does not matter anymore.
> > 
> > Doesn't it work with savecore -N /the_right_kernel ?
> 
> No; in fact, dumplo is complete garbage, so savecore fails dumping the
> image.
> 
> I suspect that the KREAD() in savecore.c does not read at the correct
> offset, and just sets garbage for dumplo.
> 
> I have to see what code path takes savecore with -N, and where it
> differs from the case where it goes through getbootfile(3) when the
> booted kernel is different from the one that is about to get dumped.

Just thinking out loud:

With the ksyms dump code I added, the "kernel image" is only used to find
the symbol table etc.  It would be nice to eventually ditch the need for
a kernel image.  Everything required is already in the dump, we just need
to extract the symbol table from ksyms.

Also, on reflection I think that crash(8) is a better all round deal than
the limited debug symbols we were thinking about previously.