The document provides instructions for compiling the Linux kernel and submitting a first patch. It lists prerequisites like VMware Player, VirtualBox, and a guest and host Linux installation. It outlines the steps to build the kernel, create a "Hello World" kernel module, make changes to it, generate a patch, apply the patch, and send the patch to an email address for review. The goal is for participants to get hands-on experience compiling the kernel and contributing a small patch back to the community.

1. Compiling Linux Kernel &
Submit First Patch
Speaker:
Mr Mayur S Patil, Asst Prof, MITAOE.

2. As linux kernel compilation is daunting task, so to save our
time I request to the participants coming for this workshop
must have following things preinstalled:
> VMware Player (If possible, VMware tools also)
> Virtualbox
> Guest and Host Linux Installed (Fedora or CentOS)
> Thunderbird Email client as mentioned in schedule.
Strict Requirement

3. Plan of Talk
❖ Very Brief history of Linux
❖ Let's Build Kernel right away
❖ Uh………..But where is my driver?
❖ Writing your first Linux Kernel Module
❖ Send it to Mail

4. Hope you all are ready with prerequisites that I mentioned
Check these packages:
# yum install ncurses-devel
# yum install rsyslog
# yum install gcc
Start the Game

5. Source Code Uncompress
To extract code at desired location,
# tar -Jxvf linux-3.12.42.tar.xz -C /usr/src
Enter into Directory
# cd /usr/src
Create a link to original one
# ln -s linux-3.x.x/ linux-fudcon
# cd linux-fudcon/

6. Start Compilation
To clean config+prev backup+prev files
# make mrproper
To copy old config file
# cp /usr/src/kernels/3.10.x/.config /usr/src/linux-fudcon/
To start build
# make localmodconfig

7. Time to create image
# make bzImage
To compile modules only
# make modules
To install modules
# make modules_install

8. Time to install the Kernel images
# make install
Time to reboot as compilation process completed
# reboot

9. Hello World Module
Create a dir at non-root user location
$ cd Documents/LKP/
https://github.com/ramlaxman/LKP/
Contains two files:
- hello.c
- Makefile (Be careful with name and its contents)
Now go to Directory of Modules
$ make

10. Loading Module….
Log in as root
# insmod hello.ko
# lsmod | less
# tail -f /var/log/messages
Now unload module
# rmmod hello
# dmesg

11. Create a patch
Now make create copy of hello.c and make
changes into that:
$ cp hello.c hello1.c
After making changes,
$ diff -u hello.c hello1.c > hello.patch
Apply patch,
$ patch < hello.patch

12. Send your patch to:
kernel-training@lukaselsner.de
[Will disabled later]
Use thunderbird settings.

13. Thanks to:
Lukas Elsner: For email Domains
Greg Kroah-hartman: For advice on building kernel like
Speedy Machine
and of course,
Audience !!