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

Geert Uytterhoeven
2026-03-03T08:11:49Z

On Tue, 3 Mar 2026 at 07:26, Richard Weinberger <richard@nod.at> wrote:
> > Von: "Sasha Levin" <sashal@kernel.org>
> > Add CONFIG_KALLSYMS_LINEINFO, which embeds a compact address-to-line
> > lookup table in the kernel image so stack traces directly print source
> > file and line number information:

> > Memory footprint measured with a simple KVM guest x86_64 config:
> >
> > Table: 4,597,583 entries from 4,841 source files
> > lineinfo_addrs[] 4,597,583 x u32 = 17.5 MiB
> > lineinfo_file_ids[] 4,597,583 x u16 = 8.8 MiB
> > lineinfo_lines[] 4,597,583 x u32 = 17.5 MiB
> > file_offsets + filenames ~ 0.1 MiB
> > Total .rodata increase: ~ 44.0 MiB
> >
> > vmlinux (stripped): 529 MiB -> 573 MiB (+44 MiB / +8.3%)
>
> Hm, that's a significant increase.

Other random idea: this data is only needed in case of a crash.
Perhaps it can be stored compressed, and only be decompressed
when needed, or even during look-up?

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

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when I'm talking to journalists I just say "programmer" or something like that.
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