https://bugs.kde.org/show_bug.cgi?id=518206
Mathias <[email protected]> changed: What |Removed |Added ---------------------------------------------------------------------------- Status|NEEDSINFO |RESOLVED --- Comment #17 from Mathias <[email protected]> --- After more investigation, it turns out I was running `mesa-amber`. I switched to it at some point in early 2025 to work around an unrelated bug that's apparently long since fixed. Reinstalling regular `mesa` makes plasmashell show up on the GPU again and the stuttering is gone. For anyone finding this later: on Intel UHD CometLake-H (Gen 9.5, i915) under kwin 6.5, plasmashell was rendering on the GPU via mesa-amber's classic `i965_dri.so` driver, which still supports Gen 9.5 hardware. Under kwin 6.6 plasmashell logs `Failed to query DMA-BUF formats`, holds no `/dev/dri/*` FDs, loads `swrast_dri.so`, and renders in software via `wl_shm`, hence the stutter. I haven't dug into exactly what changed in the negotiation between 6.5 and 6.6, but with proper mesa (iris) it's a non-issue. Not really worth a fix on the kwin side since mesa-amber on Gen 9.5 hardware is the wrong stack to begin with, happy to close. Leaving the explanation here in case the next person to hit this finds it. -- You are receiving this mail because: You are watching all bug changes.
