HOWTO on modules in 2.6.5

[afaiq]

Is there a conceptual write-up on how modules work in 2.6 vs earlier versions of the kernel? I've googled around, but most of the documents talk about a specific module not about modules in general.

[Loki3]

There might be a kernel-developers or kernel-hacker's howto on tldp.org. Also try looking at kernel.org to see if they have any developer information. There should also be documenation in your kernel source about specific modules/features.

[JohnT]

Originally posted by afaiq
Is there a conceptual write-up on how modules work in 2.6 vs earlier versions of the kernel? I've googled around, but most of the documents talk about a specific module not about modules in general. Is there a specific question you have?

[bwkaz]

Try the Documentation/ directory in the kernel source. ;)

Specifically, files like Documentation/debugging-modules.txt, Documentation/driver-model/*, and maybe some others (look around). I'm not sure if these will answer your questions, but they might. Also take a look at the source for module-init-tools; that might help some also.

[JohnT]

Here's a post on "module versioning" and patching module tools, written when the 2.5 was still in early development which leads to where we are at today in the 2.6

http://www.uwsg.iu.edu/hypermail/linux/kernel/0301.3/0272.html

[afaiq]

Originally posted by JohnT
Is there a specific question you have?

just trying to undertand the change from modules.conf to modprobe.conf (reasons and why it is better!) and if there is a change in what modules need to be compiled in the kernel vs as loadable modules.

Thanks Loki3, JohnT and bwkaz for all the suggestions. tldp.org seems to have some of what I was looking for:

http://tldp.org/HOWTO/Module-HOWTO/index.html

This site together with some other stuff in the Documentation directory in the kernel source seems to be a good starting point.

[bwkaz]

The thing that's better isn't modprobe.conf versus modules.conf. The thing that's better is module-init-tools versus modutils. ;)

Modutils used to do a lot of work to load a kernel module. Much of that work was greatly simplified by moving it into kernel space, and only providing three system calls to user space. Module-init-tools uses these three system calls to tell the kernel module loader to load a specific module.

Module-init-tools still tracks dependencies, I think, and tells the kernel to insert modules in the order that satisifies all of those dependencies. But the kernel actually does the symbol resolution, the linking into kernel memory, etc., etc., where modutils used to do a good chunk of that.