Linux Kernel Compilation - ryzendew/Linux-Tips-and-Tricks GitHub Wiki

Linux Kernel Compilation Guide

Complete beginner-friendly guide to kernel compilation on Linux, covering Arch Linux, CachyOS, and other distributions including downloading kernel source, configuring, compiling, and installing custom kernels.

Table of Contents

  1. Preparing for Compilation
  2. Downloading Source
  3. Configuring Kernel
  4. Compiling Kernel
  5. Installing Kernel
  6. Troubleshooting

Preparing for Compilation

Install Tools

Install build tools:

# Arch/CachyOS
sudo pacman -S base-devel linux-headers

# Debian/Ubuntu
sudo apt install build-essential linux-headers-$(uname -r)

# Fedora
sudo dnf groupinstall "Development Tools"
sudo dnf install kernel-devel

Check Requirements

Verify tools:

# Check GCC
gcc --version

# Check Make
make --version

# Check kernel headers
ls /usr/src/linux-headers-*

Downloading Source

Get Kernel Source

Arch/CachyOS:

# Get kernel source using asp
asp update linux
asp checkout linux

# Or download from kernel.org
wget https://www.kernel.org/pub/linux/kernel/v6.x/linux-6.1.tar.xz
tar xf linux-6.1.tar.xz
cd linux-6.1

Debian/Ubuntu:

# Download kernel source
apt source linux-source

Fedora:

# Download kernel source
dnf download --source kernel

Configuring Kernel

Kernel Configuration

Configure kernel:

# Copy existing config
cp /proc/config.gz .
gunzip config.gz
cp config .config

# Or use defaults
make defconfig

# Configure (menu-based)
make menuconfig

# Or use existing config
zcat /proc/config.gz > .config
make olddefconfig

Configuration Options

Common options:

  • menuconfig: Text-based menu
  • xconfig: X11 GUI (requires Qt)
  • gconfig: GTK GUI
  • oldconfig: Use existing config

Compiling Kernel

Build Kernel

Compile:

# Get number of CPUs
nproc

# Compile (use all CPUs)
make -j$(nproc)

# Build modules
make modules

# Install modules
sudo make modules_install

What it does:

  • Compiles kernel image
  • Builds kernel modules
  • Takes time (30 minutes to hours)

Installing Kernel

Install Kernel

Arch/CachyOS:

# Copy kernel
sudo cp arch/x86/boot/bzImage /boot/vmlinuz-linux-custom

# Update bootloader (GRUB)
sudo grub-mkconfig -o /boot/grub/grub.cfg

# Or systemd-boot
sudo cp arch/x86/boot/bzImage /boot/EFI/arch/vmlinuz-linux-custom

Debian/Ubuntu:

# Install kernel
sudo make install

# Update bootloader
sudo update-grub

Fedora:

# Install kernel
sudo make install

# Update bootloader
sudo grub2-mkconfig -o /boot/grub2/grub.cfg

Troubleshooting

Compilation Errors

Common issues:

# Check errors
make -j$(nproc) 2>&1 | tee build.log

# Clean build
make clean

# Reconfigure
make menuconfig

Boot Issues

If kernel doesn't boot:

# Boot from previous kernel
# Select from GRUB menu

# Check logs
journalctl -k

# Verify kernel
uname -r

Summary

This guide covered kernel compilation for Arch Linux, CachyOS, and other distributions, including preparation, source download, configuration, compilation, and installation.

Next Steps

This guide covers Arch Linux, CachyOS, and other Linux distributions. For distribution-specific details, refer to your distribution's documentation.