Kernel Development Learning Pipeline

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A2 - The Big Upgrade 🎢

Build, install, and boot the latest Linux kernel fresh off Linus Torvalds’ tree.

Outcomes:

• Set up a kernel development environment.
• Get comfortable with building the kernel.

Procedure:

• Get access to a Linux system on which you have root permissions.

• Install dependencies:

  • On Fedora, you can use: sudo dnf builddep kernel

  • This roughly equivalent to:

    sudo dnf -y install gcc flex make bison openssl openssl-devel elfutils-libelf-devel ncurses-devel bc git tar dwarves

• Install ccache to speed up subsequent kernel builds:

  sudo dnf -y install ccache

  Be sure to restart your terminal after installing ccache so that it gets added to your path

• Clone the latest Linux kernel: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git.

• Compile the kernel with a custom version tag.

    # clone the kernel tree
  
    git clone https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
  
    # change the current directory to the kernel tree
  
    cd linux
  
    # change the current directory to the kernel tree
  
    cp /boot/config-$(uname -r)* .config
  
    # set any new config options to the defaults
  
    make olddefconfig
  
    # to add label to the new kernel version string,
  
    # edit ‘Makefile” and add something cool to the ‘EXTRAVERSION’ variable
  
    # you can print the new version string to test it by:
  
    make kernelversion
  
    # build the kernel
  
    # -j species the number of threads
  
    # nproc finds the correct number for your machine
  
    make -j $(nproc)
  
    # install the modules
  
    # you need to be root for this step so use sudo
  
    sudo make modules_install -j $(nproc)
  
    # install the new kernel
  
    sudo make install
  
    # reboot – hopefully the new kernel is set as the default :)
  
    reboot
  
    ...
  
    uname -a
  
    dmesg | head
  
    whoami
  

• Seems easy enough right? 😉
• Expect the compilation to take a little while Make sure you have 5-10 GB of free space on the partition where you are storing the kernel tree and a bit of extra space on whatever partition /boot resides in to store the new kernel image and initramfs.

What to submit:

• The output of uname -a and dmesg | head and whoami on the system running your newly compiled Linux kernel. Make a copy of template.md in the assignment directory renamed to firstname_lastname.md and submit it as a patch.

• Don’t forget a cover letter.

Submission Guidelines