Mesa 21.2 Lands NVIDIA's Code For Handling Alternate GBM Backends

Earlier this year was the proposed NVIDIA code from NVIDIA for allowing Mesa's GBM to support alternative back-ends. This support is notable given that most Wayland compositors are catering to using Mesa's Generic Buffer Manager (GBM) rather than EGLStreams or other options for buffer management. That support code has now been merged into Mesa 21.2.

This code that was merged on Tuesday allow for GBM alternative back-end discovery and loading rather than just the built-in DRI back-end used by the open-source drivers.

This allows for back-ends to be supplied dynamically via external modules and driver ABI versioning to deal with binary compatibility between the GBM loader and varying back-ends.

That merge request is now landed. With it being upstreamed for Mesa 21.2, presumably NVIDIA will soon be shipping a proprietary driver update with their external GBM back-end library for further improving their Wayland support.