- Ubuntu Kernel Team warns of a temporary AMD GPU performance regression in compute-heavy workloads, with slowdowns up to 42x.
- The regression is in Ubuntu's forthcoming kernel update 7.0.0-28.28 for Ubuntu 26.04 and 24.04 LTS HWE users.
- Issue stems from an upstream Linux 7.0 point release bug affecting ROCm workloads like ComfyUI and Stable Diffusion XL.
- The performance problem is due to a retry loop in AMDGPU HMM code, already fixed in Linux 7.0.13 upstream.
- Ubuntu is shipping kernel 7.0.0-28.28 despite the regression to provide security fixes; a follow-up release will include the fix.
- Users relying on AMD ROCm compute are advised to avoid kernel version 7.0.0-28.28.