Independent developer enables Intel XeSS XMX upscaling in Proton for Arc GPUs

Open-source developer Patrick has released xess-xmx-linux, an experimental project that enables Intel's XeSS upscaling technology to use XMX matrix acceleration units when running under Valve's Proton compatibility layer. The implementation uses a shim DLL that intercepts driver queries alongside a patched Mesa ANV driver that compiles XeSS kernels using Intel's IGC compiler on the user's machine, allowing the Windows XeSS libraries to function without waiting for Intel's official native Linux port. The project supports both XeSS super resolution and frame generation, including multi-frame generation with reduced latency as of the latest release, and has been verified on Intel Arc GPUs ranging from the A310 through the B580 and B390.

This fills a gap left by Intel's ongoing but incomplete official Proton support effort, which aims to produce a native Linux XeSS library. Tested titles include Forza Horizon 6, Cyberpunk 2077, and Resident Evil 4. The developer notes the project is now substantially complete after several months of work, with community reports confirming functionality across multiple Intel graphics generations and handheld devices including the ONEXPLAYER 3 and MSI Claw running SteamOS.

How xess-xmx-linux bridges XeSS to Proton

• Shim DLL architecture: A custom igdext64.dll based on Intel's dxvk-igdext intercepts XeSS driver queries and responds as Intel's Windows driver would, eliminating the need for native Linux XeSS libraries.
• Mesa ANV patching: The patched ANV driver compiles XeSS compute kernels using Intel's Graphics Compiler (IGC) at runtime on the user's machine, enabling XMX unit execution rather than falling back to DP4a shader instructions.
• Frame generation support: Multi-frame generation operates as on Windows, with the latest update reducing latency by default for generated frames.
• FSR 3.1+ interoperability: Games implementing FSR 3.1 or newer can substitute XeSS super resolution and XeSS frame generation in place of FSR, providing an alternative upscaling path.
• Kernel compatibility: Patch series are provided for Mesa 26.1.2 stable and 26.3.0-rc3, with development and validation performed on SteamOS using an ONEXPLAYER 3 with Arc B390 (Xe3) graphics.

Why it matters

For Linux gamers with Intel Arc hardware, this project removes a significant capability gap versus NVIDIA DLSS and AMD FSR by enabling hardware-accelerated XeSS before Intel's official solution ships. The approach of runtime kernel compilation via IGC within Mesa may inform how other vendor-specific upscaling technologies could be adapted to Proton, particularly for handheld consoles like the Steam Deck if Intel enters that GPU market. Distribution maintainers and SteamOS developers should note the Mesa version-specific patching requirement, which will need ongoing rebasing as Intel's upstream ANV driver evolves.