Building the Linux Kernel

Compiling the Linux Kernel involves multiple steps and can take some time depending on your hardware specifications.

Step 1: Download the Kernel Source Code

Start by visiting the Official Linux Kernel Website and downloading the latest available kernel source code. The downloaded file will be a compressed archive containing all necessary source files.

Step 2: Extract the Source Code

Once the download completes, extract the contents of the compressed archive using the tar command:

tar xvf linux-6.13.tar.xz

If the tar utility is not installed on your system, you can install it using:

sudo pacman -S tar

Note: Always ensure you are using the correct version number in the file name.

Step 3: Install Required Dependencies

To compile the kernel, you need to install various development tools and libraries. Install them using the following command:

sudo pacman -S git fakeroot ncurses xz bc flex bison base-devel kmod cpio perl binutils util-linux jfsutils e2fsprogs xfsprogs squashfs-tools quota-tools

Step 4: Configure the Kernel

  1. Navigate into the kernel source directory:
cd linux-6.13

  1. Use your current system’s configuration as a base:

    • If zcat is available, run:

      zcat /proc/config.gz > .config

    • Otherwise, use this alternative method:

      cp /proc/config.gz ./
gunzip config.gz
mv config .config

  2. Customize the kernel using a menu-driven interface:

    make menuconfig
make xconfig
make oldconfig

  3. Modify the .config file directly:

    • Open it with a text editor:

      sudo vim .config

    • Search for the line:

      CONFIG_EXT4_FS=m

      And change it to:

      CONFIG_EXT4_FS=y

Step 5: Compile the Kernel

  1. Determine the number of CPU cores available to speed up compilation:
nproc
  1. Compile the kernel using the number of cores found above. Replace n with that number:
make -j<n>

If you encounter any errors during or after this step, back up your .config file and reset the source tree with:

make mrproper

This command cleans the build environment and restores the source tree to its original state.

Step 6: Install Kernel Modules

Kernel modules are essential for extending the kernel’s functionality and ensuring compatibility with various hardware. Install them with:

sudo make modules_install

Step 7: Install the Kernel

You can install the compiled kernel using one of the two methods below:

  1. Automatic installation:
sudo make install

  1. Manual installation (if the above doesn’t work):

    • Copy the kernel image:

      sudo cp arch/x86/boot/bzImage /boot/vmlinuz-linux-custom

    • Copy the System.map file:

      sudo cp System.map /boot/System.map-linux-custom

    • Copy the kernel configuration file:

      sudo cp .config /boot/config-linux-custom

Step 8: Update the Bootloader

If you use GRUB, follow these steps to add an entry for your custom kernel:

  1. Find the UUID of your root partition:
lsblk -f
  1. Open the custom GRUB configuration file:
sudo nvim /etc/grub.d/40_custom
  1. Add the following entry (replace paste-your-root-partition-uuid-here with the actual UUID):
menuentry 'Custom Linux Kernel' {
    linux /boot/vmlinuz-linux-custom
    root=UUID=paste-your-root-partition-uuid-here
    initrd /boot/initramfs-linux.img
}

Step 9: Generate Initramfs

As you’ve compiled a new kernel, installed modules, and modified boot entries, generating a new initramfs is necessary. Run:

sudo mkinitcpio -k 6.13-custom -c /etc/mkinitcpio.conf -g /boot/initramfs-linux-custom.img

Make sure the version (6.13-custom) matches your compiled kernel.

Step 10: Update GRUB Configuration

Finally, update the GRUB configuration so that it includes your new kernel entry:

sudo grub-mkconfig -o /boot/grub/grub.cfg

Done!

Congratulations! You’ve successfully compiled and installed your custom Linux Kernel. Enjoy your personalized system!