Re: [RFC] kallsyms: embed source file:line info in kernel stack traces

On Tue, Mar 03, 2026 at 11:35:26AM -0500, Sasha Levin wrote:
> On Tue, Mar 03, 2026 at 08:17:48AM -0500, Steven Rostedt wrote:
> > On Tue, 3 Mar 2026 08:39:36 +0300 Alexey Dobriyan wrote:
> >> On Mon, Mar 02, 2026 at 03:28:28PM -0500, Sasha Levin wrote:
> >> >   [   11.206749]  dump_stack_lvl+0x5d/0x80 (lib/dump_stack.c:94)
> >>
> >> This is super useful, thanks.
> >>
> >> Can the 0x prefix be dropped as well?
> >
> > And print in decimal? Without the 0x, it could be ambiguous that it's hex.
> >
> >> It is shorter to print in decimal up to 1 million.
> >>
> >> () are just character noise, I'd drop them
> >
> > I actually prefer them ;-)
> >
> > Anyway, this looks more like a feature that is for us kernel developers
> > debugging our own kernels than something that should be added to a distro.
> > decode_stacktrace.pl can be used for those because distro kernels always
> > supply debug data that can be downloaded at any time.
> 
> You know, that's what I thought when I was writing that little "bug bot" you
> saw yesterday: if I just construct the right prompts for each distro, the LLM
> can go ahead and fetch debug symbols and translate those call traces for us.

What's the advantage using an LLM/agent here ? Mapping a string to a URL
seems easy enough, especially given that ...

> What I've learned (and I might be mistaken, so corrections welcome!) is:
> 
>   - Debian is pretty good at it, but they don't store debug symbols for the
>     security archive. As an example, my build machine is currently running
> 6.17.13+deb14-amd64, and for the life of me I can't dig up the debug symbols
> even manually.
> 
>   - Fedora only provides the latest kernel. We can fish the older ones from
>     Koji, but it's quite hard nailing down the correct ones.
> 
>   - Arch simply doesn't provide debug symbols.
> 
>   - Tumbleweed provides only 30 days of archives.
> 
>   - Gentoo (binary packages) doesn't provide them at all (though is planning to).
> 
>   - Ubuntu provides them for the lifetime of the release, but their forums are
>     full of reports of missing symbols and server issues.
> 
>   - Rocky is similar to ubuntu
>     (https://forums.rockylinux.org/t/rocky-9-4-still-missing-kernel-debuginfo-common/15169
> for example).

... it sounds like we need to work with distros to improve availability
of downloadable debuginfo, so we'll know the URLs.

-- 
Regards,

Laurent Pinchart