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

On Tue, 3 Mar 2026 at 07:26, Richard Weinberger <[email protected]> wrote:
> > Von: "Sasha Levin" <[email protected]>
> > 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 -- [email protected]

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds