Re: changeset: Make forced module loading optional

[Linus Torvalds <torvalds@linux-foundation.org>]

On Mon, 5 May 2008, Rusty Russell wrote:
> 
>    I'm trying to figure out how you did this.  So fedora builds unversioned 
> modules, and version (and vermagic) matched your kernel?  And you somehow 
> mixed them up?

I don't use modules much, so many of my kernels tend to have modules off 
entirely. However, the Intel wireless drivers used to not work when 
built-in (fixed now, but I still had a legacy config), so my laptop had 
modules enabled, and MODVERSIONS set.

And I don't build initrd's etc crap, very much on purpose. I want to 
replace the kernel, nothing else, so my /etc/grub.conf file just replaces 
the distro kernel with my own, and keeps everything else untouched.

>    I don't think relying on modversions is the complete answer here.  Perhaps 
> we should make modules_install blow away old modules?

Wouldn't help one whit, and is against my rules anyway. See above. I want 
my own kernel, no other changes. That means that I run the distro initrd, 
which has its modules for bringing stuff up with distro kernels.

And quite frankly, when I finally figured out what was going on, I was 
like *WHAT THE HELL*. That kernel/module.c code was absolute and utter 
crap in accepting modules that neither matched the kernel version 
signature (because it had CONFIG_MODVERSIONS) *nor* the actual versioned 
symbols (because the distro modules had been built without 
CONFIG_MODVERSIONS).

So no, I'm not at all interested in blowing away old modules. I'm 
interested in having a module loader that isn't complete and utter crap 
and bypasses all the sanity checks that it has.

Which is what that changeset basically does.

People can still set CONFIG_MODULE_LOAD_FORCE, but quite frankly, I 
suspect that anybody who does that is just insane and/or works with 
proprietary and broken modules. So it's off by default, and hopefully no 
distro will ever set it.

			Linus