Re: [PATCH 01/23] scripts/mksysmap: drop the MODULE_INFO() symbols from kallsyms

[Nathan Chancellor]

> Commit 3e86e4d74c04 ("kbuild: keep .modinfo section in vmlinux.unstripped")
> keeps .modinfo symbols out of System.map and kallsyms, which assumes unique
> IDs have a format like '__UNIQUE_ID_modinfo123'.
> 
> However, commit afb026b6d35c ("compiler: Tweak __UNIQUE_ID() naming"), sent
> in the same cycle, changes this to '__UNIQUE_ID_modinfo_123'.
> 
> As a result this regexp has never matched and every kernel since v6.18 has
> carried one kallsyms entries for every MODULE_INFO() declaration in the
> kernel whether the modules are compiled or not.
> 
> That's 5,810 entries for an x86 defconfig build and 15,200 for arm64.
> 
> On x86 defconfig that is 113 KiB of kallsyms tables and 32 KiB of bzImage,
> and every lookup walks past them.

Bummer :/

> Fix the pattern.
> 
> Fixes: 3e86e4d74c04 ("kbuild: keep .modinfo section in vmlinux.unstripped")
> 
> No measurable change in build time, the smaller tables are not on any path
> the build waits for.

I don't think this needs to be in the commit message, it could be below
the fold, since it appears to be a valid fix on its own. Agree with
Nicolas on adjusting the Fixes tag.

Is this worth Cc'ing stable for?

> Assisted-by: LLM
> Signed-off-by: Lorenzo Stoakes (ARM) <ljs@xxxxxxxxxx>

Reviewed-by: Nathan Chancellor <nathan@xxxxxxxxxx>

-- 
Cheers,
Nathan