Collect the tips of linux kernel development

Example1

The simplest kernel module demo

Example2

Enhance Example0, append module infomation, parameter

Parameter Passing: insmod example.ko debug_enable=1 dispstr="World"

Dyanamicly change the parameter via sysfs

List Module Info: modinfo brook.ko

Example3

DebugFS Example

Dynamicly change the variable via debugfs

Need to mount debugfs

Example4

Sysctl Example Register sysctl_table and it becomes a subdir of /proc/sys

Can read/write value via /proc/sys

After kernel 2.6.33, sysctl is only the wrapper of procfs.

It cannot viist from syscall anymore.

Example5

Syscall Example

Register a misc device, communicate between user space and kernel space.

Implement file_operation, mmap, ioctl

Example6

ProcFS Example(Without seq_file)

Example7

ProcFS Example(With seq_file example)

Example8

Netlink Example (Communicate between user space and kernel space)