Re: [commit] Unwinder for OpenBSD/sparc64 kernel trap frames

Daniel Jacobowitz
2006-12-31T15:05:44Z

On Sun, Dec 31, 2006 at 01:36:38PM +0100, Mark Kettenis wrote:
> Heh, I believe you raised the same question when I added the same code
> to i386 and amd64. At that time I believe I convinced you that this
> was acceptable.

Oh right :-) Shows you what my memory is worth these days.

> Adding Linux kernel debugging support is much harder. The rate of
> change is much higher, there are kernel modules (which have a slightly
> odd format). And of course Linux doesn't have kernel core dumps, so
> it would only be useful to debug a live kernel.

I'm not sure about all of these, except the last one - there's at least
one implementation of crash dumps for Linux. It's still not common,
though, more's the pity.

> > Anyway, I have some thoughts on how to extend the unwind mechanism so
> > that the OpenBSD kernel could ship a script that knew how to unwind its
> > trap frames.
>
> Did you really mean to say OpenBSD here?

Well, *BSD. I mean, specifically, a script that does the same thing
the patch to sparc64obsd-tdep.c does. Whether it actually gets bundled
with OpenBSD or with GDB is an interesting question, I guess :-)

--
Daniel Jacobowitz
CodeSourcery