Re: [PATCH modules-next v10 00/13] kallsyms: reliable symbol->address lookup with /proc/kallmodsyms

From: Petr Mladek
Date: Tue Apr 25 2023 - 04:28:01 EST


On Mon 2023-04-24 12:47:39, Luis Chamberlain wrote:
> On Fri, Apr 07, 2023 at 04:21:18PM -0700, Josh Poimboeuf wrote:
> > Anyway, I was nodding along with the above cover letter until I got to
> > the third paragraph.
> >
> > A "built-in kernel module" is not actually a module, as it's built in to
> > vmlinux. I suspect the point is that if you rebuild with a different
> > config, it might become a module. But many other changes could also
> > occur with a changed config, including changed inlining decisions and
> > GCC IPA optimization function renaming, in which case the symbol might
> > no longer exist with the new config.
>
> Yes it does not matter, for his tooling effort it was just to be able
> to map a possible module to a symbol so tooling can display this to
> disambiguate.

Note that the same symbol name might be used many times even within
one module. The module might be linked from more .o files. And
more .o files might have a local symbol with the same name.

I think that the best solution is to associate the symbol with
the file name and line. These is very useful information in general.

Best Regards,
Petr