MyOS - Bare Bones Operating System

A minimal x86 operating system following the OSDev bare bones tutorial.

Features

• Multiboot-compliant bootloader
• Basic kernel setup
• GRUB2 bootloader integration
• Runs on x86 (i686) architecture

Prerequisites

To build this OS, you need:

• i686-elf cross-compiler (GCC and binutils)
• GRUB (grub-mkrescue and grub-common)
• xorriso (for ISO creation)
• QEMU (for testing - qemu-system-i386)

Installing the Cross-Compiler

Follow the OSDev GCC Cross-Compiler guide to build your cross-compiler.

The cross-compiler should be available in your PATH or you can modify the Makefile to point to its location.

Building

# Build everything
make all

# Clean build artifacts
make clean

Running

To run the OS in QEMU:

qemu-system-i386 -cdrom myos.iso

Project Structure

.
├── boot.s          # Assembly bootloader with multiboot header
├── kernel.c        # Main kernel code
├── linker.ld       # Linker script
├── grub.cfg        # GRUB configuration
├── makefile        # Build automation
└── README.md       # This file

How It Works

1. Bootloader (boot.s): Sets up the multiboot header, stack, and calls the kernel
2. Kernel (kernel.c): The main kernel entry point
3. Linker Script (linker.ld): Organizes the memory layout
4. GRUB: Loads the kernel using the multiboot specification

Resources

• OSDev Wiki - Bare Bones
• OSDev Wiki - Multiboot
• GRUB Multiboot Specification

License

This is a learning project. Feel free to use and modify as needed.