Bug 465585

Created attachment 156152 [details]
additional info

If launching fullsceen applications on external HDMI display with offload to discrete NVIDIA GPU the external HDMI display will freeze. Attempting to close the application or switch to a different virtual desktop does not help, as the HDMI display output itself seems to be "frozen".
On X11 I can go to Plasma system settings and turn on and off the external display to get the HDMI output unfreeze. Attempting to do this on Wayland will make the whole GUI freeze, switching to a different TTY will not work.
In most cases NVIDIA GPU will keep rendering stuff as it should, so I can have both the frozen HDMI output and Cyberpunk 2077 running on NVIDIA GPU at the same time (but of course Cyberpunk will be shown on the builtin Laptop display).
If I try to shutdown my laptop after getting this bug, the laptop will never turn off by itself and the external HDMI Display will still be showing the same last frame that was rendered before before freezing.
*HDMI output is controlled by the NVIDIA GPU

Bug appears more often in 3D scenes than in 2D.
Bug can't be reproduced without offload to the NVIDIA GPU. 

This bug appeared after an NVIDIA driver update during the 5xx driver version updates, not after switching from 4xx to a 5xx driver.
Please see this bug report, it's important: https://forums.developer.nvidia.com/t/525-78-01-nvidia-card-hdmi-output-freezes-after-launching-fullscreen-applications/236161

Goal of this report is to find out if the NVIDIA itself is the problem. 


STEPS TO REPRODUCE
1. Launch a fullscreened application on external HDMI output with offload to the NVIDIA GPU
2. Get external display frozen after a short time since application launch
3. Blame NVIDIA

OBSERVED RESULT


EXPECTED RESULT


SOFTWARE/OS VERSIONS
Linux/KDE Plasma: openSUSE Tumbleweed
KDE Plasma Version: Plasma 5.26.5
KDE Frameworks Version: 5.102.0
Qt Version: 5.15.8

ADDITIONAL INFORMATION
See the attached archive