PVGPU - Paravirtualized GPU for Windows VMs

GPU paravirtualization for Windows guests on Windows hosts - bringing QEMU/KVM-style VM customization freedom to Windows while providing GPU acceleration for gaming.

🎯 The Problem We Solve

On Linux, QEMU/KVM + VFIO gives you:

• ✅ Full VM identity customization (SMBIOS, CPUID, firmware)
• ✅ GPU passthrough for near-native gaming performance

On Windows, your options are limited:

• Hyper-V/NanaBox: GPU-PV works, but no identity customization
• QEMU with WHPX: Full customization, but no GPU acceleration for Windows guests
• VMware/Parallels: Proprietary, limited customization

PVGPU bridges this gap - run Windows VMs with QEMU's customization AND GPU acceleration, all on a Windows host.

🏗️ Architecture

┌─────────────────────────────────────────────────────────────────┐
│  Windows Guest (10/11)                                          │
│  └── Game/App (DX11) → WDDM Paravirt Driver (KMD + UMD)         │
│            │                                                    │
│            ▼ Shared Memory (Command Rings + Fences)             │
├─────────────────────────────────────────────────────────────────┤
│  QEMU (WHPX acceleration)                                       │
│  └── qemu-pvgpu device (PCIe virtual, BAR0 config, BAR2 shmem)  │
│            │                                                    │
│            ▼                                                    │
├─────────────────────────────────────────────────────────────────┤
│  Host Backend Service (Rust)                                    │
│  └── D3D11 Renderer → Real GPU (NVIDIA/AMD)                     │
│  └── Presentation: Local window + Headless/Streaming            │
└─────────────────────────────────────────────────────────────────┘

📦 Components

Component	Language	Description
protocol/	C	Shared protocol definitions
qemu-device/	C	QEMU PCIe device emulation
backend/	Rust	Host rendering service (D3D11)
driver/kmd/	C	Windows kernel-mode WDDM driver
driver/umd/	C++	Windows user-mode D3D11 driver

🚀 Quick Start

Prerequisites

• Windows 11 with Hyper-V/WHPX enabled
• NVIDIA (10 series+) or AMD (RDNA+) GPU
• Rust (for backend)
• QEMU with WHPX support
• Windows Driver Kit (for driver development)

Building

# Build the backend service
cd backend
cargo build --release

# For QEMU device - see qemu-device/README.md
# For drivers - see driver/README.md

Running

# Start the backend service
.\backend\target\release\pvgpu-backend.exe

# Start QEMU with pvgpu device
qemu-system-x86_64 -accel whpx -device pvgpu,shmem_size=256M ...

🎮 Use Cases

• Gaming in VMs with GPU acceleration AND custom VM identity
• Anti-fingerprinting - appear as different hardware to guest OS
• Development/Testing - test on various "hardware" configurations
• Streaming - works with Parsec, Moonlight, Sunshine

📊 Performance Targets

• Target: 60-80% of native GPU performance
• Latency: <50ms additional input latency
• API: DirectX 11 (DX12 planned for future)

🛣️ Roadmap

• Protocol definition (shared header, command types, feature flags)
• QEMU PCIe device (BAR0 config, BAR2 shared memory, MSI-X, named pipe IPC)
• Rust backend service (D3D11 renderer, command processor, presentation pipeline)
• Full D3D11 command implementation (50+ DDI functions, all draw/state/resource commands)
• WDDM kernel-mode driver (BAR mapping, ring buffer, heap allocator, VidPn, interrupt handler)
• WDDM user-mode driver (D3D11 DDI, staging buffer, fence sync, compute shader support)
• Display mode support (720p-4K, 60-144Hz, dynamic resolution change)
• Presentation pipeline (windowed, headless, dual mode, VSync, frame events)
• Format support data (78 DXGI formats with capability flags)
• Shared resource opening (cross-process resource sharing)
• Compute shader support (CS dispatch, UAV, SRV, sampler, constant buffer binding)
• Error handling and robustness (device lost, OOM, shader errors, backend crash)
• Driver packaging (INF, WDK build configs, CI pipeline)
• Integration testing (requires VM environment)
• Performance optimization (profiling, command batching, telemetry)
• DX12 support (future)

🤝 Contributing

Contributions are welcome! This is an ambitious project that needs help with:

• D3D11/D3D12 expertise
• Windows driver development
• QEMU device development
• Testing on various hardware

See CONTRIBUTING.md for guidelines.

📜 License

Dual-licensed under MIT and Apache 2.0. See LICENSE-MIT and LICENSE-APACHE.

QEMU device code is GPL-2.0-or-later to match QEMU's license.

🙏 Acknowledgments

Inspired by:

• dxgkrnl - GPU-PV for WSL2
• virtio-gpu - QEMU's GPU virtualization
• Looking Glass - Low-latency VM display

⚠️ Disclaimer

This project is for legitimate use cases like development, testing, and privacy. It is not intended for bypassing anti-cheat systems or any malicious purposes.