Kernel Programming

This is the home page for the "Kernel Programming" course. Here, you will find (in a badly-organised form) all the material, slides, and information needed to attend the course

For the previous edition of the course, check the old website.

Lessons:

• First lesson: 2019/02/26, 13:00 -> 15:30
  • Introduction to the course
  • Example of toy kernel that just boots
• Second lesson: 2019/03/05, 9:30 -> 12:00
  • Introduction to the Linux kernel
  • A minimal Linux-based OS
  • Linux kernel modules
• Third lesson: 2019/03/13, 11:00 -> 13:30
  • Testing kernel modules in a simple VM
  • Something more about user-space/kernel-space interactions
• Fourth lesson: 2019/03/19, 9:30 -> 12:00
  • More examples with misc devices
  • Blocking a task; TASK_INTERRUPTIBLE vs TASK_UNINTERRUPTIBLE
• Fifth lesson: 2019/03/26, 9:30 -> 12:00
  • Something about kernel mutexes
  • Bug in the mutex example, and how to debug it
  • First example of cooperative synchronization
  • Coping with signals
• Sixth lesson: 2019/04/02, 9:30 -> 12:00
  • Cooperative synchronization done right, the waitqueues
  • Fixing the bug in the previous example (coping with signals)
  • Using the Linux kernel completions
  • Linux kernel lists

Slides:

• Introduction to the course
• Introduction to Linux kernel modules
• Something more about OS Kernels (the "interesting" slides are from 7 to 35)
• Something notes on locking in a real kernel

Example Code:

• Example of toy kernel that just boots and prints some information
• The simplest Linux kernel module
• Linux kernel modules: first examples
• Possible solution for the exercise proposed in the third lesson
• Linux kernel modules: examples on competitive and cooperative synchronization
• Coping with signals when blocking
• Linux kernel modules: examples on completions and waitqueues
• Using the Linux kernel lists
• Simple IPC mechanism based on misc devices and kernel lists
• Example about kernel threads; more complex example with kernel threads and misc devices

Other Material:

• Basic OS image for testing the modules (built with https://gitlab.retis.sssup.it/l.abeni/BuildCore.git)
• Instructions for creating and modifying the simple OS image
• To test a Linux kernel (or module) in a VM while saving the kernel messages in a text file on the host (for debugging, or similar), add '-append "console=tty console=ttyS0" -serial file:log.txt' (use the file name you prefer instead of log.txt) to the qemu command line