Advantages and disadvantages of loader in system software
Answers
Explanation:
Advantages
Loading and unloading a module is much more flexible and faster than recompiling a kernel and rebooting.
You can try different options each time you load a module. Most drivers that handle hardware will take options for I/O addresses, IRQ or DMA numbers, plus more esoteric options like full or half duplex. When you have problems getting a card to run correctly, the ability to try different options can save hours.
Makes it easier to maintain multiple machines on a single kernel base.
Disadvantages (TANSTAAFL)
You have to plan ahead and decide which modules to compile.
Modules have to be loaded. This can be manual or automatic but it still has to be done.
Symbol tables for modules are dynamic which complicates oops debugging. ksymoops has to jump through hoops to extract the full and current symbol table for a module. klogd does not do it correctly, nor does SGI's kdb.
Some people consider modules to be a security risk because a cracker can load a module which hides itself and their code from the real administrator. Personally I consider this to be misleading. Only root can load modules and if a cracker already has root then your machine is dead anyway.