Fedora KDE becomes suddenly slow

I can reproduce this as of linux-firmware-20241017. The “amdgpu.dcdebugmask=0x10” kernel param workaround works for now

Occurs with my computer as well, AMD, Fedora 40, GNOME

Michael1 mentioned it occurs for them when watching video, and all the occurrences for me as well have been while watching youtube

just happened to me on Fedora 41 with gnome. Was on Youtube as well. Just applied the kernel param so hopefully that will be the end of it for now

Well, thought it was fixed after amdgpu firmware 20241017-2, but just had it happen twice tonight.

Oct 31 21:14:12 fedora kernel: amdgpu 0000:c1:00.0: [drm] ERROR dc_dmub_srv_log_diagnostic_data: DMCUB error - collecting diagnostic data
Oct 31 21:14:12 fedora kernel: amdgpu 0000:c1:00.0: [drm] ERROR dc_dmub_srv_log_diagnostic_data: DMCUB error - collecting diagnostic data
Oct 31 21:14:12 fedora kernel: amdgpu 0000:c1:00.0: [drm] ERROR dc_dmub_srv_log_diagnostic_data: DMCUB error - collecting diagnostic data
Oct 31 21:14:12 fedora kernel: sched: RT throttling activated
Oct 31 21:14:12 fedora kernel: amdgpu 0000:c1:00.0: [drm] ERROR dc_dmub_srv_log_diagnostic_data: DMCUB error - collecting diagnostic data
Oct 31 21:14:11 fedora kernel: amdgpu 0000:c1:00.0: [drm] ERROR dc_dmub_srv_log_diagnostic_data: DMCUB error - collecting diagnostic data
Oct 31 21:14:11 fedora kernel: amdgpu 0000:c1:00.0: [drm] ERROR dc_dmub_srv_log_diagnostic_data: DMCUB error - collecting diagnostic data

Forcing amdgpu reset as suggested upthread does make it go away without a restart.

This happens for me on arch / endevouros. So it’s not fixed in the bleeding edge either sadly.

Adding that this still occurs even with Fedora 41. No idea as to cause.

Same problem with Fedora 41 (Gnome 47, Linux kernel 6.11.5-300) on my Ryzen 7840. However I think I only experienced this issue yet when my Bluetooth speakers were connected.