Bug 485899

Summary:	System-freeze when watching YouTube Videos in Firefox or Chromium
Product:	[Plasma] kwin	Reporter:	Phillip Schichtel <phillip>
Component:	core	Assignee:	KWin default assignee <kwin-bugs-null>
Status:	RESOLVED UPSTREAM
Severity:	crash	CC:	linx.system.adm, xaver.hugl
Priority:	NOR
Version First Reported In:	6.0.4
Target Milestone:	---
Platform:	Arch Linux
OS:	Linux
Latest Commit:		Version Fixed/Implemented In:
Sentry Crash Report:

Description Phillip Schichtel 2024-04-21 13:53:08 UTC

SUMMARY

Watching YouTube videos in Firefox or Chromium completely freezes my system on Plasma Wayland. Watching the same videos on the system system in a Gnome Wayland session works without issues. Both browsers are configured to use Wayland natively

When the system freezes no audio plays and I can't ssh into my machine suggesting a complete lock-up. I haven't found useful logs of the incidents, no coredumps in coredumpctl anything else useful to debug this, but it happens very reliably, pretty much any video. The freeze doesn't happen at the same point in the video everytime, sometimes sooner, sometimes later.

STEPS TO REPRODUCE
1. Login to Plasma Wayland
2. Start Firefox and open YouTube
3. Watch any video (possibly in HD?)

OBSERVED RESULT

Sooner or later the system completely locks up.

EXPECTED RESULT

The system obviously shouldn't lock up.

SOFTWARE/OS VERSIONS
Linux/KDE Plasma: Archlinux (no testing)
(available in About System)
KDE Plasma Version: 6.0.4
KDE Frameworks Version: 
Qt Version: 6.7.0 / 5.15.13

(this is my first bug report, sorry if I misconfigured stuff

Comment 1 Phillip Schichtel 2024-04-21 14:00:50 UTC

I forgot to mention:

My GPU is a vega64 using AMDGPU on kernel `6.8.7-arch1-1` with `amdgpu.gpu_recovery=0 amdgpu.ppfeaturemask=0xffffffff`.

Comment 2 username 2024-04-21 15:18:01 UTC

It looks like this is a bug in amdgpu driver https://gitlab.freedesktop.org/drm/amd/-/issues/2156

Comment 3 Phillip Schichtel 2024-04-21 15:43:47 UTC

interesting, I might try that patch.

Though a few concerns:

1. I'm not sure that change applies to my hardware
2. I don't see any of the relevant log lines that the original reporter there observed
3. most importantly: why does it hang the system in KDE, but not in Gnome? Does KDE allow for more hardware decoding compared to Gnome and has thus a higher chance of hitting this?

Comment 4 Phillip Schichtel 2024-04-21 21:20:40 UTC

The patch indeed seems to help. I'll monitor it for a few more days, but I think a freeze would already have happened.

Comment 5 Zamundaaa 2024-04-23 23:58:44 UTC

> most importantly: why does it hang the system in KDE, but not in Gnome? Does KDE allow for more hardware decoding compared to Gnome and has thus a higher chance of hitting this?
I don't think so, but GPU driver bugs are sometimes triggered by specific patterns in how rendering is done, or by buffer formats (like 10 bits per color with KWin vs 8 with other compositors), there can be many differences that can make one happen or not happen.

Anyways, total system freezes like that are always kernel bugs; if it seems GPU driver related you can directly create the an issue on drm,/amd about it in the future

Comment 6 Phillip Schichtel 2024-04-24 23:55:20 UTC

Ok. Just a final update: The patch mentioned by @username was indeed not related, according to Alex Deucher it only affects navi21 and I also wasn't able to reproduce the issue after reverting the an unpatched kernel. Not sure what else changed, but this went from "happens on every video even across reboots" to "doesn't happen at all" basically overnight. Maybe some package update snug in that I didn't notice.