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

Jiri Slaby
2026-03-03T09:31:51Z

On 03. 03. 26, 9:11, Geert Uytterhoeven wrote:
> 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?

But obviously not when dumping OOM stack traces :P.

--
js
suse labs