Hypervisor & Virtualization Deep Dive - Expanded Project Guides

Generated from: HYPERVISOR_VIRTUALIZATION_DEEP_DIVE_PROJECTS.md

Overview

Master hypervisor and virtualization technology from first principles through 15 hands-on projects. You’ll progress from building simple CPU emulators (CHIP-8, RISC-V) through binary translation and JIT compilation, then tackle memory virtualization with shadow page tables and EPT, implement virtual devices (UART, block storage, networking), explore Intel VT-x hardware virtualization, and culminate in building a complete Type-2 hypervisor capable of running Linux.

Goal: Deeply understand how hypervisors work, from basic CPU emulation to hardware-assisted virtualization, culminating in building your own VM system like QEMU.

What You’ll Master:

  • CPU emulation and the fetch-decode-execute cycle
  • Binary translation and JIT compilation (how QEMU’s TCG works)
  • Memory virtualization (shadow page tables and EPT)
  • Device emulation (UART, virtio-blk, virtio-net)
  • Intel VT-x hardware virtualization (VMCS, VM entries/exits)
  • Full system integration (running real operating systems)

Project Index

# Project Difficulty Time Key Focus
1 CHIP-8 Interpreter Emulator Beginner 1 week CPU Emulation / Instruction Decoding
2 Simple RISC CPU Emulator Intermediate 2-3 weeks CPU Architecture / ISA Design
3 Basic Block Binary Translator Advanced 3-4 weeks Binary Translation / JIT Compilation
4 Simple JIT Compiler Advanced 3-4 weeks JIT Compilation / Dynamic Code Generation
5 Shadow Page Table Simulator Advanced 2-3 weeks Memory Virtualization / Page Tables
6 User-Space Memory Mapper Intermediate 1-2 weeks Memory Management / mmap
7 Virtual Serial Port (UART) Intermediate 1-2 weeks Device Emulation / UART
8 Virtual Block Device Advanced 3-4 weeks Block Device Emulation / Storage
9 Virtual Network Interface Advanced 3-4 weeks Network Virtualization / TAP Devices
10 VMX Capability Explorer Advanced 1-2 weeks Intel VT-x / Hardware Virtualization
11 Minimal VT-x Hypervisor Expert 4-6 weeks Hypervisor Development / VT-x
12 EPT Implementation Expert 2-3 weeks Memory Virtualization / EPT
13 Mini-QEMU Clone Expert 6-8 weeks Full System Emulation
14 KVM Userspace Client Advanced 2-3 weeks KVM API / Hardware Virtualization
15 Complete Type-2 Hypervisor Master 3-6 months Complete Hypervisor / VT-x + Devices

Learning Paths

Path 1: New to Systems Programming

Start with fundamentals and work up:

  1. P01 - CHIP-8 Interpreter - Understand fetch-decode-execute
  2. P02 - RISC-V Emulator - Real CPU architecture
  3. P06 - Memory Mapper - Memory management basics
  4. P07 - UART Emulator - Simple device emulation

Path 2: Understanding QEMU

Focus on software emulation and binary translation:

  1. P02 - RISC-V Emulator - CPU emulation
  2. P03 - Binary Translator - Static translation
  3. P04 - JIT Compiler - Dynamic translation
  4. P13 - Mini-QEMU Clone - Full integration

Path 3: Hardware Virtualization

Focus on Intel VT-x:

  1. P10 - VMX Capability Explorer - Discover VT-x capabilities
  2. P11 - Minimal VT-x Hypervisor - Basic VT-x hypervisor
  3. P12 - EPT Implementation - Memory virtualization with EPT
  4. P14 - KVM Userspace Client - Using KVM API

Path 4: Memory Virtualization

Focus on address translation:

  1. P05 - Shadow Page Tables - Pre-EPT technique
  2. P06 - Memory Mapper - User-space techniques
  3. P12 - EPT Implementation - Hardware-assisted EPT

Path 5: Complete Journey (6-12 months)

Phase Timeline Projects Focus Area
1 Month 1-2 P01-P02 Emulation fundamentals
2 Month 2-3 P03-P04 Binary translation
3 Month 3-4 P05-P06 Memory management
4 Month 4-5 P07-P09 Device emulation
5 Month 5-7 P10-P12 Hardware virtualization
6 Month 7-9 P13-P14 Integration
7 Month 9-12 P15 Capstone

Prerequisites

Essential

  • C programming (intermediate level) - All projects use C as the primary language
  • Understanding of binary/hexadecimal - Instruction encoding, memory addresses
  • Basic Linux command line - Building, running, debugging
  • Familiarity with assembly concepts - Registers, instructions, memory

Helpful

  • x86 assembly experience - Required for binary translation projects (P03-P04)
  • Understanding of operating system concepts - Virtual memory, page tables, interrupts
  • Linux kernel module development - Required for hardware virtualization projects (P10-P12)
  • RISC-V assembly - Helpful for Projects 2-3

Hardware Requirements

| Projects | Hardware Needed | |———-|—————–| | P01-P09, P13 | Any Linux machine | | P10-P12, P15 | Intel CPU with VT-x and EPT support | | P14 | Linux with KVM enabled |


Core Concepts Overview

The Virtualization Stack

+-------------------------------------------------------------+
|                    Guest Applications                        |
+-------------------------------------------------------------+
|                    Guest Operating System                    |
+-------------------------------------------------------------+
|                Virtual Hardware (Emulated)                   |
|   +----------+----------+----------+----------+----------+   |
|   |  vCPU    | vMemory  |  vDisk   |  vNIC    |  vUSB    |   |
+---+----------+----------+----------+----------+----------+---+
|                  Hypervisor / VMM                            |
|   +-------------------+-----------------------------+        |
|   | CPU Virtualization|     Device Emulation        |        |
|   | (VT-x/Software)   |     (QEMU-style)            |        |
|   +-------------------+-----------------------------+        |
+-------------------------------------------------------------+
|                    Host OS (optional)                        |
+-------------------------------------------------------------+
|                    Physical Hardware                         |
|   +----------+----------+----------+----------+----------+   |
|   |   CPU    |   RAM    | Storage  |   NIC    |   USB    |   |
|   +----------+----------+----------+----------+----------+   |
+-------------------------------------------------------------+

QEMU Clarified

QEMU is NOT a hypervisor by itself - it’s an emulator:

Mode What It Does Speed Use Case
QEMU alone Pure software emulation via TCG (Tiny Code Generator) Slow (~10-100x slower) Cross-architecture (ARM on x86)
QEMU + KVM QEMU handles devices, KVM handles CPU/memory via VT-x Near-native Same-architecture virtualization
QEMU + Xen QEMU provides device models for Xen guests Near-native Enterprise virtualization

Hypervisor Types

Type Description Examples
Type 1 (Bare-metal) Runs directly on hardware, no host OS VMware ESXi, Xen, Hyper-V, KVM*
Type 2 (Hosted) Runs on top of a host OS VirtualBox, VMware Workstation, QEMU

*KVM is technically a kernel module, making Linux itself the hypervisor.

CPU Virtualization Techniques

Technique How It Works Performance Complexity
Interpretation Fetch-decode-execute each instruction in software Very slow Simple
Binary Translation Translate blocks of guest code to host code (JIT) Moderate Complex
Trap-and-Emulate Run guest directly, trap on privileged instructions Fast (if possible) Moderate
Hardware-Assisted (VT-x/AMD-V) CPU has special VMX mode for guests Near-native Complex setup, simple execution

Project Progression

Level 1: Interpreter Emulators (Understand the basics)
    |
    +-- Project 1: CHIP-8 Interpreter
    +-- Project 2: Simple RISC CPU Emulator
    |
Level 2: Binary Translation & JIT (How QEMU's TCG works)
    |
    +-- Project 3: Basic Block Translator
    +-- Project 4: Simple JIT Compiler
    |
Level 3: Memory Virtualization (The address space illusion)
    |
    +-- Project 5: Shadow Page Table Simulator
    +-- Project 6: Memory Mapper with Protection
    |
Level 4: Device Emulation (Virtual hardware)
    |
    +-- Project 7: Virtual Serial Port (UART)
    +-- Project 8: Virtual Block Device
    +-- Project 9: Virtual Network Interface
    |
Level 5: Hardware-Assisted Virtualization (VT-x/AMD-V)
    |
    +-- Project 10: VMX Capability Explorer
    +-- Project 11: Minimal VT-x Hypervisor
    +-- Project 12: EPT Memory Virtualization
    |
Level 6: Integration (Full VM System)
    |
    +-- Project 13: Mini-QEMU Clone
    +-- Project 14: KVM Userspace Client
    |
Level 7: Capstone
    |
    +-- Project 15: Complete Type-2 Hypervisor

Project Comparison Table

# Project Difficulty Time Depth Fun Hardware Needed
1 CHIP-8 Interpreter Beginner 1 week ** ***** None
2 RISC-V Emulator Intermediate 2-3 weeks *** ** None
3 Basic Block Translator Advanced 3-4 weeks ** ** None
4 JIT Compiler Advanced 3-4 weeks ** ***** None
5 Shadow PT Simulator Advanced 2-3 weeks ***** *** None
6 User-Space Memory Mapper Intermediate 1-2 weeks *** *** None
7 Virtual UART Intermediate 1-2 weeks *** *** None
8 Virtual Block Device Advanced 3-4 weeks ** ** None
9 Virtual Network Interface Advanced 3-4 weeks ** ***** None
10 VMX Capability Explorer Advanced 1-2 weeks *** *** Intel VT-x
11 Minimal VT-x Hypervisor Expert 4-6 weeks ***** ***** Intel VT-x
12 EPT Implementation Expert 2-3 weeks ***** ** Intel EPT
13 Mini-QEMU Clone Expert 6-8 weeks ***** ***** None
14 KVM Userspace Client Advanced 2-3 weeks ** ***** Linux + KVM
15 Complete Type-2 Hypervisor Master 3-6 months ***** ***** Intel VT-x + EPT

Essential Resources

Books

  1. “Computer Systems: A Programmer’s Perspective” by Bryant & O’Hallaron - Foundation for everything
  2. “Intel SDM Volume 3C” (Chapters 23-33) - The bible for VT-x
  3. “Operating Systems: Three Easy Pieces” by Arpaci-Dusseau - Memory virtualization
  4. “The Definitive Guide to the Xen Hypervisor” by David Chisnall - Hypervisor architecture
  5. “The Linux Programming Interface” by Michael Kerrisk - System programming

Tutorials

  1. Hypervisor From Scratch - 8-part series covering VT-x implementation
  2. Writing a Hypervisor in 1000 Lines - Minimal RISC-V hypervisor
  3. QEMU Internals - Deep dive into QEMU architecture
  4. HyperDbg Documentation - VT-x concepts explained

Specifications

  1. Intel SDM - Official Intel documentation
  2. VIRTIO Specification - Virtio device standard
  3. KVM API - Linux KVM interface
  4. RISC-V Specification - For Projects 2-3

Project Summaries

# Project Name Main Language What You’ll Build
1 CHIP-8 Interpreter Emulator C Complete emulator running classic games (Pong, Tetris)
2 Simple RISC CPU Emulator C RV32I emulator with debugger, runs compiled C programs
3 Basic Block Binary Translator C Static translator: RISC-V to x86-64 (100x speedup)
4 Simple JIT Compiler for Bytecode VM C Runtime code generator for hot path optimization
5 Shadow Page Table Simulator C Pre-EPT memory virtualization technique
6 User-Space Memory Mapper with Protection C Guest memory manager with MMIO support
7 Virtual Serial Port (UART) Emulator C 16550 UART connecting to host PTY
8 Virtual Block Device (Disk) Emulator C virtio-blk device with file backing
9 Virtual Network Interface (virtio-net) C virtio-net with TAP device backend
10 VMX Capability Explorer C Kernel module querying VT-x features
11 Minimal VT-x Hypervisor C VMCS setup, VM entry/exit handling
12 EPT Implementation C Hardware-assisted memory virtualization
13 Mini-QEMU Clone C Full system emulator booting simple OS
14 KVM Userspace Client C Userspace VM using Linux KVM API
15 Complete Type-2 Hypervisor (Capstone) C Full hypervisor running Linux with SMP

Expected Outcomes

After completing this learning path, you will be able to:

  1. Explain how emulators work - From CHIP-8 to full system emulation
  2. Understand binary translation - How QEMU’s TCG achieves reasonable performance
  3. Implement JIT compilation - Generate native code at runtime
  4. Master memory virtualization - Shadow page tables and EPT
  5. Build virtual devices - UART, block storage, network interfaces
  6. Use Intel VT-x - VMCS configuration, VM entries/exits
  7. Work with KVM - Use Linux’s virtualization infrastructure
  8. Build a complete hypervisor - Boot and run Linux as a guest

After completing these projects, you’ll have gone from “I don’t know if QEMU is a hypervisor” to “I built my own hypervisor that runs Linux.” You’ll understand virtualization at every level: software emulation, binary translation, hardware-assisted virtualization, memory virtualization, and device emulation. This is deep systems knowledge that very few developers possess.