WINQ-EMU

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The best way to run a full graphical Linux desktop on Windows — with real Vulkan GPU acceleration, Wayland compositor support, and host folder sharing.

Three Things That Make It Different

• Better WHPX Support — Full -cpu host passthrough (not available in upstream QEMU), hybrid CPU P-core/E-core topology detection, sub-millisecond timer resolution
• Venus Vulkan GPU Forwarding — Your Linux VM uses your real GPU for Vulkan. No software rasterization.
• Enhanced SDL Display — DPI-aware SDL display with USB tablet support (no freezing), automatic host refresh rate matching, and Venus Vulkan GPU acceleration.

Download

Grab the latest installer from Releases.

Quick Start

1. Install WINQ-EMU
2. Place a Linux qcow2 image in the vm folder
3. Double-click WINQ-EMU.exe (GUI) or launch-vm.bat (script)
4. SSH in: ssh -p 2223 user@localhost

Performance

SuperTuxKart, Vulkan renderer, default settings, CachyOS on both:

	FPS
WINQ-EMU (Venus)	410
WSL2 (CachyOS)	226

Features

• Vulkan: Works everywhere (Wayland + X11) via Venus
• OpenGL: Works everywhere via virgl (GL forwarding)
• Zink (GL-over-Vulkan): Works on Wayland and X11/XWayland
• Folder sharing: virtio-9p host ↔ guest folders via the GUI launcher's Folder Sharing tab
• Hardware video decode (experimental): VA-API for H.264, HEVC (Main / Main10), VP9 (Profile 0 / Profile 2), AV1 — routed through the host GPU's DXVA pipeline. Opt-in from the Experimental tab.

Important: Use BIOS boot, not EFI. EFI boot causes a timing issue that tanks Vulkan performance to ~5 FPS.

Folder Sharing (9p)

Open the GUI launcher, go to the Folder Sharing tab, add a host folder with a mount tag, launch the VM, then inside the guest:

sudo mkdir -p /mnt/<tag>
sudo mount -t 9p -o trans=virtio,version=9p2000.L <tag> /mnt/<tag>

For auto-mount at boot, add to /etc/fstab:

<tag>  /mnt/<tag>  9p  trans=virtio,version=9p2000.L,nofail,_netdev  0 0

Changes propagate both ways.

Hardware Video Decode (VA-API) — Experimental

VA-API is off by default. Enable it from the Experimental tab in the launcher (or set WINQ_VAAPI=1 in the environment before launching qemu-system-x86_64.exe directly).

With it enabled, Mesa's virgl Gallium VA driver in the guest forwards decode commands to virglrenderer on the host, which runs the actual decode on ID3D11VideoDecoder (DXVA). Decoded frames flow back to the guest as virtio-gpu resources that libva consumers read through vaGetImage / vaMapBuffer.

Supported codecs:

Codec	Profiles
H.264	Constrained Baseline, Main, High (8-bit 4:2:0)
HEVC	Main (8-bit), Main10 (10-bit)
VP9	Profile 0 (8-bit), Profile 2 (10-bit)
AV1	Main Profile 0 (8-bit)

Confirm inside the guest with vainfo.

Known-good consumers (anything that uses the vaGetImage / vaapi-copy path): ffmpeg, mpv (--hwdec=vaapi-copy), VLC, Haruna, GStreamer.

Why it's experimental

Chromium-based browsers (Chrome, Brave, Edge, Opera, Vivaldi), and mpv with --hwdec=vaapi (non-copy) take a zero-copy path via vaExportSurfaceHandle + EGL_LINUX_DMA_BUF_EXT. That path is not yet functional through virglrenderer on Windows — you'll see black or garbled video. For now the only reliable workarounds for Chromium users are:

• Disable hardware video acceleration in the browser:
  • chrome://settings/system → uncheck "Use hardware acceleration when available", or
  • chrome://flags → search for "hardware-video-decoding" → set to Disabled.
• Or prefer mpv / VLC / Haruna for video playback, where the copy path works.

Firefox and every non-Chromium consumer tested above work correctly.

Guest Requirements

• Linux distro with Mesa 26.0+ (Fedora 41+, Ubuntu 25.04+, Arch, CachyOS, etc.) for the VA-API video driver
• Mesa 24.0+ is enough for Vulkan-only use
• Wayland compositor recommended (KDE Plasma, GNOME)

Building from Source

Prerequisites

• MSYS2 with the UCRT64 environment
• .NET Framework 4 (included with Windows — provides csc.exe at C:\Windows\Microsoft.NET\Framework64\v4.0.30319\)

Build Order

1. Build virglrenderer — see winq-emu-virglrenderer. Configure with -Dvenus=true -Dvideo=true -Dtests=false (the -Dvideo=true flag is required for the D3D11 video decode backend that Zink-on-Wayland and VA-API both depend on). Run ninja -C builddir install to install libvirglrenderer-1.dll to /ucrt64/bin.
2. Build QEMU — see winq-emu-qemu. Produces qemu-system-x86_64.exe, qemu-system-x86_64w.exe (no console window), and qemu-img.exe.
3. Build the frontend (from this repo):

   csc.exe /target:winexe /out:installer\WINQ-EMU.exe /win32icon:launcher\winq-emu.ico /r:System.Windows.Forms.dll /r:System.Drawing.dll launcher\WINQ-EMU.cs
   

4. Collect DLLs — copy all UCRT64 DLL dependencies into installer\bin\. Use ldd qemu-system-x86_64.exe from the UCRT64 shell to find them. Also copy winq-emu.ico into installer\icons\ for the window icon.
5. Build the installer (requires mingw-w64-ucrt-x86_64-nsis):

   cd installer && makensis installer.nsi

Status

Alpha 10 - It works, it's fast, but expect some rough edges. Stability improvements are ongoing.

What's New in Alpha 10

• WHPX IA32_PAT MSR sync — Linux uses PAT to mark virtio-gpu / Venus shared memory as Write-Combining. Previously the partition's PAT was not synchronised with the guest, so the guest's MTRR/PAT cache-type computation could fall back to UC for memory that should be WC. Vulkan/OpenGL workloads that move significant GPU memory should be measurably faster on alpha 10.
• WHvAdviseGpaRange(Pin) for large RAM regions (Windows 11 24H2+) — pin SLAT entries for the base RAM and the Venus 4 GiB hostmem region so the hypervisor doesn't demote 2 MiB / 1 GiB pages to 4 KiB under host memory pressure. Removes a "60 fps → 30 fps with no apparent cause" cliff under heavy graphics.
• 5 ms cap on the WHPX inner exit loop — a guest spinning through cheap MMIO/CPUID/MSR exits during a Vulkan submit storm could keep a vCPU thread inside the hypervisor for tens of ms, blocking the QEMU main loop. Smoother frame pacing under heavy graphics.
• UnimplementedMsrAction = IgnoreWriteReadZero (Windows 11 24H2+) — Linux probes a couple hundred MSRs at boot that we don't implement. Each used to be a full WHPX exit just to be told "0". Now the hypervisor zero-reads them in-kernel. Slightly faster boot, lower steady-state overhead.
• FastHypercallOutput for x86 — every Hyper-V hypercall (TLB shootdown, IPI cluster) returns via registers instead of a guest-physical output page. Removes one mapping fault per hypercall.
• VkAccelerationStructureKHR deferred destroy on Windows — extends the Intel-ICD-handle-recycle workaround to ray-tracing AS handles. RT games (Quake II RTX, Portal RTX, vkd3d-proton) destroy and recreate AS every frame as TLAS rebuilds.
• Multi-disk support in the launcher — the Disk Image section is now a table of (Path, Format, Interface) rows. Add as many qcow2/raw images as you want; pick virtio / scsi / ide per disk. The first disk boots by default. Exported .bat files round-trip multiple -drive lines.
• WINQ_DIAG=1 umbrella diagnostic flag — one switch turns on every existing per-module diagnostic stream and routes the log to %LOCALAPPDATA%\winq-emu\virglrenderer.log. Replaces the VIRGL_VIDEO_DIAG / VIRGL_VIDEO_D3D11_DEBUG / VIRGL_LOG_FILE / VIRGL_LOG_LEVEL matrix when capturing a bug report.
• Four upstream virglrenderer fixes cherry-picked: NULL-resource deref in virgl_renderer_resource_map_fixed (guest-triggerable crash), vrend_renderer_init cleanup order on init failure, vkr_allocator instance NULL on vkCreateInstance failure, cursor orientation Y_0_TOP flip.

What Was New in Alpha 9

• Vulkan WSI no longer stalls the dispatcher per frame. The host's vkWaitSemaphoreResourceMESA and vkResetFenceResourceMESA paths used to do synchronous GPU waits and expensive Win32 handle export/close ceremonies on every guest WSI present. They now match Linux's non-blocking semantics — the dispatcher returns immediately and lets the GPU consume the semaphore signal in the background. This was a real per-frame stall on every Vulkan game and Wayland workload.
• Sub-millisecond Windows timer resolution. virgl_renderer_init now sets timeBeginPeriod(1) and vkr_ring_relax uses CreateWaitableTimerEx HIGH_RESOLUTION for sub-millisecond delays. Without these, the ring monitor's microsecond-scale sleeps were rounded up to the 15.625ms system timer tick — the dispatcher would oversleep into the next frame, missing a whole burst of guest commands.
• Ring + queue threads register with MMCSS ("Pro Audio"). The two latency-sensitive worker threads now get longer time slices and are less likely to be preempted by background work. Reduces frame-time jitter on Vulkan workloads.
• No QEMU code changes vs Alpha 8 — same v11.0.0 base.

What Was New in Alpha 8

• Rebased on QEMU 11.0.0 (final release, up from the 11.0.0-rc3 snapshot used in Alpha 7).
• Rebased on the virglrenderer 1.3.0 stable tag (replacing the development-tip snapshot used in Alpha 7), so the patch series now sits on a tagged, reproducible upstream tree.
• No functional changes vs Alpha 7 — same Windows-host Venus + virtio-gpu + 9pfs + D3D11 video decode feature set.

What Was New in Alpha 7

• Zink on Wayland — Zink (GL-over-Vulkan) now works under native Wayland compositors, not only X11/XWayland. Enabled by a Windows dma-buf shim that synthesizes VK_EXT_external_memory_dma_buf and VK_EXT_image_drm_format_modifier on top of the host Vulkan ICD so guest Wayland compositors can import Vulkan-allocated surfaces.
• VA-API moved to experimental — now off by default; enable from the launcher's Experimental tab. The copy path (mpv/VLC/Haruna) remains reliable; the zero-copy path used by Chromium is still broken and is being tracked as a separate project.
• Rebased on latest upstream QEMU + virglrenderer.

What Was New in Alpha 6

• virtio-9p folder sharing — share Windows folders with the Linux guest via the Folder Sharing tab in the GUI launcher. Uses the Windows port of QEMU's 9pfs backend.
• VA-API hardware video decode — H.264, HEVC (Main / Main10), VP9 (Profile 0 / Profile 2), and AV1 (Main Profile 0) decode through the host GPU's DXVA pipeline.
• Rebased on latest upstream QEMU + virglrenderer.

What Was New in Alpha 5

• USB mouse fix: Configurations generated by the GUI now correctly include -usb -device usb-tablet for proper mouse input
• Disk image tools: qemu-img is now bundled with the installer, so the GUI can create qcow2 disk images out of the box
• Rebased on QEMU v11.0.0-rc3 and latest upstream virglrenderer

What Was New in Alpha 4

• Keyboard fix: Dynamic keyboard layout detection for OEM keys (backslash, brackets, etc.) — works correctly on US, UK, ISO, JIS, and all other layouts
• Install location: Default install to C:\WINQ-EMU instead of AppData

Contributing

Anyone is welcome to look at, modify, and/or merge these changes into upstream projects. The patches are intentionally kept minimal and clean for upstreaming.

License

• QEMU: GPL-2.0
• virglrenderer: MIT
• Launcher/installer: MIT