is_module()

[Jarkko Sakkinen]

Hi,

I just put this here while I still have it on my mind. Possibly I'm
ignoring something that already enables this but at least I learn
something by doing this then. 

This came up in a recent discussion albeit for this crypto bug it
did not make waves because the bug fix did not require it:

https://lore.kernel.org/linux-integrity/D1GXKODMD4S8.1J12D4GOEQWPL@xxxxxxxxxx/

So the gist of  is_module() would be that it would have different
semantics than IS_MODULE(): it could be used to e.g. check modules in a
loop.

Compilation would generate a new ELF section with following entries:

<ASCIIZ string><0 or 1>

The string would contain module name, and 1 could be marking for
being a module, and 0 for being builtin.

Also, it would enabled to add lsmod -b to enumerate built-in modules,
which would give nice way to carve up more information about a running
test kernel. This would obviously need perhaps a new file to procfs for
built-in modules (for regular there is /proc/modules).

Not fighting for having this, just makig it visible.

BR, Jarkko