> On Jul 19, 2022, at 9:57 AM, Mouse <mo...@rodents-montreal.org> wrote:
>
>
> [EXTERNAL EMAIL]
>
> I've been exchanging email off-list about this with a few people. One
> of them remarked that a kernel coredump would help.
>
> Yesterday it wedged again. I got a kernel coredump...and, well, as I
> put it in off-list mail:
>
>>> I now realize I don't know how to coax [process stack traces] out of
>>> a kernel core. I don't recall hearing of any sort of postmortem
>>> ddb. I have a the corresponding netbsd.gdb, and I found gdb's
>>> target kvm, but I haven't manged to get a stack trace for any
>>> process out of it.
>
> The response turned out to be exactly the cluesticking I needed to get
> stack traces.
I did a pile of work on GDB, 10 or more years ago, to add that
capability for the non-standard system coredumps we used in EqualLogic.
It's not a simple change, if you want it to be fairly automatic. Part
of it means looking into user mode memory, but another part is loading
all the right symbol tables with the right relocations.
Unfortunately I'm not in a position to dig up that code, adapt it to
the standard NetBSD kernel dumps, and contribute it. I could ask for
approval to contribute my changes as-is for some interested person to
adapt. If that's interesting, please let me know and I can pursue it.
pul
