When should I write a Linux kernel module?

Question

Some people want to move code from user space to kernel space in Linux for some reason. A lot of times the reason seems to be that the code should have particularly high priorit

Answer 1

As general rule. Think on what you want to know and if that is something you would see in an operating system development book or class then it has a good chance to belong into the kernel. If not, keep it out of the kernel. If you have a very good reason to break that rule, be sure, you will have enough knowledge to know it by yourself or you will be working with someone that has that knowledge.

Yes, might sound harsh, but this exactly what I meant, if you don't know, then be almost sure the answer is no, don't do it in the kernel. Moving your development to kernel space opens a giant can of worms that you must be sure to be able to handle.