Kevin OS

A minimalist operating system kernel written in Rust, following the blog_os tutorial series.

Features

• Bare metal Rust environment
• VGA text mode output
• Interrupt handling
• Memory management with paging
• Heap allocation
• Async/await support
• Keyboard input handling
• Multitasking

Prerequisites

• Rust nightly toolchain
• QEMU for x86_64 architecture
• bootimage tool
• For WSL users: VcXsrv X Server

Building and Running

# Build the kernel
cargo build

# Run in QEMU
cargo run

WSL Setup Guide

For Windows Subsystem for Linux users, follow these steps to set up a graphical environment:

1. Install VcXsrv on Windows:

   • Download from: https://sourceforge.net/projects/vcxsrv/
   • Complete the installation

2. Configure VcXsrv:

   • Launch XLaunch from the Start menu
   • Select "Multiple windows"
   • Set Display number to 0
   • Choose "Start no client"
   • Check "Disable access control" in Extra settings
   • Click "Finish"

3. Configure WSL environment:

   # Set display variable
   export DISPLAY=$(grep -m 1 nameserver /etc/resolv.conf | awk '{print $2}'):0.0
   
   # Verify DISPLAY setting
   echo $DISPLAY
   
   # Allow connections
   xhost +local:

4. Run QEMU:

   qemu-system-x86_64 \
       -drive format=raw,file=target/x86_64_kevin_os/debug/bootimage-kevin_os.bin \
       -serial stdio \
       -display sdl

   

Cargo Configuration

To simplify development, add this to your .cargo/config.toml:

[target.'cfg(target_os = "none")']
runner = "bootimage runner"

[unstable]
build-std = ["core", "compiler_builtins"]
build-std-features = ["compiler-builtins-mem"]

[build]
target = "x86_64_kevin_os.json"

[target.x86_64-kevin_os]
runner = """
bootimage runner --timeout 300
qemu-system-x86_64 \
    -drive format=raw,file=target/x86_64-kevin_os/debug/bootimage-kevin_os.bin \
    -serial stdio \
    -display sdl \
"""

Implementation Details

This OS kernel includes implementations of:

• Custom interrupt descriptor table (IDT)
• Memory paging and frame allocation
• Multiple heap allocator designs (bump, linked list, fixed-size block)
• Async/await task executor with waker support
• VGA text buffer driver for output
• PS/2 keyboard driver with scancode handling
• Simple multitasking system

Project Structure

kevin_os/
├── src/
│   ├── main.rs           # Kernel entry point
│   ├── vga_buffer.rs     # Text mode display driver
│   ├── interrupts/       # Interrupt handling code
│   │   ├── mod.rs
│   │   └── gdt.rs        # Global Descriptor Table
│   ├── memory/           # Memory management
│   │   ├── mod.rs
│   │   ├── paging.rs
│   │   └── frame.rs
│   ├── allocator/        # Heap allocators
│   │   ├── mod.rs
│   │   ├── bump.rs
│   │   ├── linked_list.rs
│   │   └── fixed_size_block.rs
│   └── task/             # Async task system
│       ├── mod.rs
│       ├── executor.rs
│       ├── keyboard.rs   # Keyboard input handling
│       └── simple_executor.rs
├── Cargo.toml
└── x86_64_kevin_os.json  # Target specification

License

This project is licensed under the MIT License - see the LICENSE file for details.

Acknowledgments

• Writing an OS in Rust by Philipp Oppermann
• The Rust OSDev community