AMD driver causing massive performance loss on all major Linux distros

Ubuntu warns an upcoming Linux kernel severely slows AMD down in certain compute workloads due to a drive issue.

Earlier today, we reported on an interesting tale wherein Windows 11, in its less-than-optimal state, performed really well against SteamOS inside the new Steam Machine. However, we also praised the SteamOS, which is based on Arch Linux, as it was able to keep up with a much more established gaming platform.

The Steam Machine runs on custom AMD hardware, and despite being generally pretty good on Linux, an upcoming kernel version has been confirmed to be causing massive performance degradation due to a driver bug.

Ubuntu engineers have warned that the upcoming 7.0.0-28.28 kernel release can lead to a very substantial 43 times performance hit on certain compute-heavy workloads. Specifically, the Ubuntu team highlighted that the regression affects the AMDGPU driver and can dramatically reduce throughput for ROCm-based applications such as Stable Diffusion XL (SDXL) inference through ComfyUI.

According to the team, workloads that were previously completed in around nine seconds have been observed taking as long as 388 seconds after upgrading to the affected kernel. Canonical has confirmed that this is a throughput regression rather than a system stability issue, so the good news is that affected systems should remain perfectly usable but will perform extremely slowly during such GPU compute tasks.

The regression originated upstream in the Linux 7.0 stable series and had already been reported by users on other distros like CachyOS and Fedora. On Ubuntu specifically, this is a targeted regression that affects Ubuntu 26.04 users along with users on the Hardware Enablement (HWE) stack for Ubuntu 24.04 who are currently scheduled to transition from the Linux 6.17 kernel to the newer 7.0 series.

While the company is still shipping kernel 7.0.0-28.28 because it includes important security fixes, it is recommending that users who rely on AMD ROCm compute workloads avoid installing the update, if possible, until the corrected kernel becomes available.

As such, Linux gamers using AMD graphics hardware are unlikely to notice any major difference in typical gaming workloads.

Source

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Posted Friday 17 July 2026 at 7:23 am AEST (my time).

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