Modules

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With the recent growth in the size of the kernel image this configuration al 

lows the kernel to stay below the size limitations of some boot loaders and still

maintain the highest level of functionality.

Many of the configuration problems associated with device drivers involve

finding the correct set of options to pass when installing the driver.

Without modules each test would require rebooting the system in order to

get the newest test options to take effect. With the module utilities supplied

with a Debian system, a module can be unloaded with the rmmod command.

The module's options can be edited in /etc/conf.modules to reflect the new

test values, and the module reinstalled with insmod, all without rebooting

the system!

With the use of kerneld, modules can be loaded and unloaded as needed.

When no access has been made to the VFAT file systems for awhile, kerneld

will unload the module and free up the memory it used. If, by chance, there

is the need to read that VFAT file system in the future, the request to the

kernel will trigger the loading of the required module by kerneld. In this

way the kernel only takes up as much memory as it actually needs to continue

with operations while maintaining the capability of accessing a wide variety of

devices and systems.

Disadvantage

  Broken or missing modules can cripple the system

  Provide opportunities for security violations

  Erratic operation of, and timing problems with, some devices

If a driver file in /lib/modules///*.o is either cor 

rupted or removed, the system can find itself without critical resources. This