[CentOS] Compiling Kernel Modules

Tue May 3 11:15:39 UTC 2005
Maciej Zenczykowski <maze at cela.pl>

Hi,

Here'a a question - is it possible to compile a single module (distributed
in the kernel source tree) for the current CentOS kernel (2.6.9-5.0.5)
without recompiling the entire kernel and all other modules.

I basically need reiserfs3 (nb. why is it disabled? it's a module, you
use it, it doesn't wreck anything...) and I don't really want to change
the rest of the kernel, and I'd like to have the minimum amount of fuss on
future kernel upgrades.

Now I know external modules can be compiled without recompiling the
kernel - question is how to do it for an internal kernel module.

What I've tried:

I've installed the kernel source code, copied over the kernel settings
(the entire /usr/src/kernels/2.6.... dir) onto it. run make menuconfig and
selected modular reiserfs.  A diff of the new and old configs shows only
reiser module (and suboptions for selinux) has been enabled.  So no other
changes have been made.

Now a make fs/reiserfs/ almost works, but it borks on some sort of
.tmp_versions/reiserfs.mod problem (file not present).  The resultant
reiserfs.o doesn't work as reiserfs.ko (not sure if it should, though).. I
can't run make modules_install without first compiling all the other
modules...  Should I just grep through the .config file and replace all
(except reiser) =m with =n's (and rerun make oldconfig to make sure it's
still consistent)?  And then run make modules modules_install?

Any ideas?  Basically all I want is reiserfs3 for the current CentOS4
kernel...

Cheers,
MaZe.