Re: [gentoo-dev] USE Linux 2.6.x

[C. Brewer]

On Tuesday 21 October 2003 9:25, Thomas de Grenier de Latour wrote:

> Because it is useful to be able to compile modules for a target kernel
> that may be different than the running kernel, and a symlink is a
> good way to point the target of your choice.

Sure, that's an excellent point, but since the target kernel and the running 
kernel are likely on the same machine, and the current state of modules in 
portage IIRC isn't allowing the duplication of external modules packages, why 
not just be booted into the one you're making modules for? You're gonna end 
up rebooting either way eventually...

> I don't see how system headers are related to modules compilation. The
> flameable symlink is the /usr/include/linux, but it's a different issue.
> It is something that on some other distros points on kernel includes
> from kernel sources, but as you said, on Gentoo, we have a linux-headers
> package and a real directory, so we do things the right way.

The only modules discussion so far, other than what you recently brought up, 
was Mike's example of how the nvidia-modules package determined the running 
kernel. The original question was how does a package(generic) determine the 
running kernel. While I agree that there are some issues with the modules 
packages that should be handled differently, no package that doesn't provide 
modules should care what kernel you're running. But there are still a few 
packages in the tree that are using that /usr/src/linux symlink to get at 
includes (iproute2 until a while back, plex86 indirectly now,fex.) A nice 
solution for the modules packages might be to allow them to slot to the 
kernel version similar to the way you can specify USE, eg. SLOT="2.6.0-test8" 
emerge nvidia-modules and have it install the modules in /lib/${SLOT}/ (keep 
in mind, I have no idea how the nvidia-modules ebuild looks, thats just a 
general example). I also realize the main flameable link was the /usr/
include/{linux|asm} link pointing back to the kernel sources, but to quote 
Linus -
" I would suggest that people who compile new kernels should:
- NOT do so in /usr/src. Leave whatever kernel (probably only the
   header files) that the distribution came with there, but don't touch
   it.

 - compile the kernel in their own home directory, as their very own
   selves. No need to be root to compile the kernel. You need to be root
   to _install_ the kernel, but that's different.

 - not have a single symbolic link in sight (except the one that the
   kernel build itself sets up, namely the "linux/include/asm" symlink
   that is only used for the internal kernel compile itself)"

1,2,3 things that haven't been done yet.. Personally I compile mine in /opt, 
because my /home is pretty full...
-- 
Chuck Brewer
Registered Linux User #284015
Get my gpg public key at pgp.mit.edu!! Encrypted e-mail preferred.