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Date:   Tue, 25 Apr 2023 10:27:42 +0200
From:   Petr Mladek <pmladek@suse.com>
To:     Luis Chamberlain <mcgrof@kernel.org>
Cc:     Josh Poimboeuf <jpoimboe@kernel.org>,
        Nick Alcock <nick.alcock@oracle.com>, masahiroy@kernel.org,
        linux-modules@vger.kernel.org, linux-trace-kernel@vger.kernel.org,
        linux-kernel@vger.kernel.org, arnd@arndb.de,
        akpm@linux-foundation.org, eugene.loh@oracle.com,
        kris.van.hees@oracle.com, live-patching@vger.kernel.org,
        Peter Zijlstra <peterz@infradead.org>,
        Steven Rostedt <rostedt@goodmis.org>
Subject: Re: [PATCH modules-next v10 00/13] kallsyms: reliable
 symbol->address lookup with /proc/kallmodsyms
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References: <20221205163157.269335-1-nick.alcock@oracle.com>
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 <ZEbc20oRFR0f8Qj6@bombadil.infradead.org>
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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