Mesa update caused GPU hang on Intel HD 4000 with Wayland and Discord
After a recent Mesa update my Intel HD Graphics 4000 entered a hard GPU hang state.
The system became unstable as soon as GPU accelerated applications were started, most noticeably Discord.
System details
Manjaro stable
Kernel 6.18.4
Mesa from stable repo
Intel HD Graphics 4000
KDE Plasma 6.5.4
Wayland session
Symptoms
Starting Discord or other Electron based applications immediately caused
black screen or frozen desktop
GPU hang and reset in the kernel
Wayland session becoming unresponsive
Reboot did not always recover the GPU until a full power cycle
What fixed it
Downgrading Mesa to the previous version immediately restored GPU stability.
After the downgrade Discord and the desktop worked normally again.
This strongly suggests a userspace driver mismatch between Mesa and the i915 kernel driver for Ivy Bridge GPUs.
Discord was only the trigger because it initializes VAAPI, WebGL and Vulkan early, but the underlying issue was Mesa.
I am posting this as a warning for other users with older Intel GPUs on Wayland.
Rolling Mesa updates can break ABI compatibility with the kernel driver and result in full GPU hangs.