D3D12 not used unless GALLIUM_DRIVER set

Windows build number:

26100.3775

Your Distribution version:

24.04

Your WSL versions:

WSL version: 2.4.13.0 Kernel version: 5.15.167.4-1 WSLg version: 1.0.65 MSRDC version: 1.2.5716 Direct3D version: 1.611.1-81528511 DXCore version: 10.0.26100.1-240331-1435.ge-release Windows version: 10.0.26100.3775

Steps to reproduce:

1. sudo add-apt-repository ppa:kisak/kisak-mesa && sudo apt-get update && sudo apt-get dist-upgrade
2. glxinfo -B | grep "OpenGL renderer" OpenGL renderer string: llvmpipe (LLVM 19.1.7, 128 bits)
3. GALLIUM_DRIVER=d3d12 glxinfo -B | grep "OpenGL renderer" OpenGL renderer string: D3D12 (Intel(R) UHD Graphics)

WSL logs:

Not sure how to enable script execution to collect the logs.

WSL dumps:

No response

Expected behavior:

D3D12 should be selected automatically on Ubuntu under WSL.

I only tried the GALLIUM_DRIVER variable after trying many other things and finding it on these issue pages.

Actual behavior:

The llvmpipe renderer is selected despite D3D12 availability.