Bug 472016 - Extreme flickering on a Wayland session on Plasma 6 when run on a VM
Summary: Extreme flickering on a Wayland session on Plasma 6 when run on a VM
Status: RESOLVED FIXED
Alias: None
Product: kwin
Classification: Plasma
Component: wayland-generic (show other bugs)
Version: git master
Platform: Neon Linux
: NOR normal
Target Milestone: ---
Assignee: KWin default assignee
URL:
Keywords: qt6, wayland
Depends on:
Blocks:
 
Reported: 2023-07-06 20:41 UTC by guimarcalsilva
Modified: 2023-10-08 18:27 UTC (History)
4 users (show)

See Also:
Latest Commit:
Version Fixed In:


Attachments

Note You need to log in before you can comment on or make changes to this bug.
Description guimarcalsilva 2023-07-06 20:41:41 UTC
SUMMARY

On a VM, Plasma 6 flickers a lot on a Wayland session. X11 is fine. The cursor is also invisible. The video below illustrates the issue:
https://www.youtube.com/watch?v=QjVXg1KtpR4

I'm using Gnome Boxes with a Linux host, however, the same is true on Virtual Box on Windows.

STEPS TO REPRODUCE
1. Launch a Plasma 6 Wayland session on a virtual machine

OBSERVED RESULT

The mouse cursor is invisible and the whole image flickers

EXPECTED RESULT
No flickering

SOFTWARE/OS VERSIONS
KDE Plasma Version: 5.27.80
KDE Frameworks Version: 5.240.0
Qt Version: 6.5.1

ADDITIONAL INFORMATION
Neon Unstable July 6th 2023.
Comment 1 Zamundaaa 2023-07-17 08:39:02 UTC
I don't know about the cursor, but the flickering is caused by https://gitlab.freedesktop.org/mesa/mesa/-/issues/9375. https://invent.kde.org/plasma/kwin/-/merge_requests/4249 should fix it
Comment 2 guimarcalsilva 2023-09-10 20:26:43 UTC
New info. I tested now with Virtualbox instead of Gnome Boxes, and there's no flickering, however, the cursor is still invisible, and all the timing of the animations is also broken. Likely a bunch of bugs. If necessary I can create separate bug reports for those.
Comment 3 Zamundaaa 2023-09-10 20:42:56 UTC
Virtualbox probably sets up some sort of OpenGl acceleration by default, which will circumvent the Mesa bug. For the cursor, see bug 474298
Comment 4 Michel Le Bihan 2023-09-14 19:12:23 UTC
Hello,
I tested the `neon-developer-20230907-1341.iso` live iso in libvirt QEMU/KVM with Virtio graphics and I noticed extreme flickering, but the cursor is visible.
Comment 5 Lassi Väätämöinen 2023-10-07 22:19:31 UTC
 I tried VIrtualBOx + Plasma Wayland on  neon-unstable-20231001-1120, after doing 'apt udpate && apt dist-upgrade', and the Wayland session did not even start. After several flickers between VirtualBox screen sizes, it went back to the SDDM login screen. Syslog showed segfaults.
Comment 6 Zamundaaa 2023-10-08 18:27:05 UTC
That's a different bug, please make a separate report for that.

For the actual bug with flickering, we've included a workaround with https://invent.kde.org/plasma/kwin/-/commit/f43e45c984382a7f02c4b9a8cf4c8c1019ad193b