Mesa Rusticl Reaches OpenCL 3.1 as Linux GPU Support Expands

Mesa's Rusticl OpenCL implementation has reached OpenCL 3.1 support as its hardware coverage continues to expand. Rusticl lead developer Karol Herbst summarized the project's 2026 progress at XDC 2026, highlighting the newer API support, additional extensions and a wider set of Gallium drivers able to expose Rusticl.

The timing is notable because Khronos only released OpenCL 3.1 in May 2026. The specification moves several previously optional capabilities into the core, including SPIR-V kernel ingestion, subgroups, integer dot products, a suggested work-group-size query and a device UUID query aligned with Vulkan.

Khronos' current conformant-product registry lists Apple M1- and M2-family systems running Asahi Linux with an OpenCL 3.1 device version through the open-source stack. That gives Apple Silicon Linux users a standards-conformant OpenCL path even though the implementation is independent of Apple's macOS graphics and compute software.

Conformance is more meaningful than simply advertising an API version: it records an implementation against the Khronos conformance test process. It still should not be read as a claim that Rusticl matches another OpenCL implementation in performance, application compatibility or supported optional features.

The 2026 status update also points to wider driver adoption. Panfrost for Arm Mali hardware has passed OpenCL conformance and now has a supported default-enable path, while Freedreno for Qualcomm Adreno hardware can likewise expose Rusticl by default. Mesa's own documentation makes an important distinction: default enablement is controlled by build configuration and driver-maintainer opt-in, so users should not assume every distribution enables every Rusticl-capable driver automatically.

That broader Gallium coverage matters because Rusticl is designed as a shared OpenCL implementation above Mesa drivers rather than a separate vendor stack for each GPU family. Improvements in the common implementation can therefore benefit multiple supported drivers, subject to each driver's capabilities and validation.

Rusticl's progress gives Mesa a more capable common OpenCL layer across otherwise very different GPU drivers. For Linux users, the practical story is less about replacing every proprietary compute stack and more about expanding standards-based compute support on hardware where an open driver path is useful.

The project is still moving. Herbst's XDC session also described newer extension work and experiments beyond the currently validated driver set. Those development directions should remain separate from what is already conformant or enabled today.