Linux Modules

lsmod - gives you a list of the current modules the kernel is using.
insmod - lets you insert a module into the active kernel (root must do this) example.
```
insmod /lib/modules/2.0.0/fs/binfmt_java.o
```
When building the kernel in /usr/src/linux you can do a make menuconfig You want to set the following things on.
- Enable loadable module support
- Set version information on all symbols for modules
- Kernel daemon support (e.g. autoload of modules)
(note this only works on certain versions of Linux, I use slackware and Linux 2.0.0) bottom line is you want the following things in your .config file
- CONFIG_MODULES=y
- CONFIG_MODVERSIONS=y
- CONFIG_KERNELD=y
Some modules don't show up in the menuconfig or config programs What I had to do with Linux 2.0.30 to get the Java module in was to add the line "CONFIG_BINFMT_JAVA=m" in my .config file by hand. I figured this out after poking around the fs directory of my linux src files and looked at the Makefile. It had an if statement which would only compile the java module if CONFIG_BINFMT_JAVA was set.

You should make sure your /etc/rc.d/rc.S or /etc/rc.d/rc.modules file contains at least this information.

 
# Update module dependencies:
echo "Starting kerneld"
if [ -x /sbin/depmod ]
then
        echo "Updating module dependencies for Linux `uname -r`:"
        /sbin/depmod -a
fi

# Automatic module loading.  To load and unload kernel modules
# automatically as needed, uncomment the lines below to run kerneld.
# In some cases, you'll need to create aliases to load the correct
# module. For more information, see the docs in /usr/doc/modules.

if [ -x /sbin/kerneld ]; then
  /sbin/kerneld
fi

If you put the above in the /etc/rc.d/rc.S file you need to take care WHERE you put it. This should happen very early in the boot process, certainly BEFORE you run fsck on filesystems that might need to have disk drivers autoloaded

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