https://bugs.kde.org/show_bug.cgi?id=527526
Bug ID: 527526
Summary: [Regression] KWin 6.8.1 causes flickering and black
rectangular artifacts on NVIDIA-driven external
DisplayPort monitor in Intel/NVIDIA hybrid GPU setup
Classification: Plasma
Product: kwin
Version First 6.8.1
Reported In:
Platform: Fedora RPMs
OS: Linux
Status: REPORTED
Severity: normal
Priority: NOR
Component: platform-drm
Assignee: [email protected]
Reporter: [email protected]
CC: [email protected]
Target Milestone: ---
DESCRIPTION
After upgrading KWin from 6.8.0 to 6.8.1 on Fedora 44 with a hybrid
Intel/NVIDIA GPU configuration, my external DisplayPort monitor, connected to
the NVIDIA GPU, started exhibiting continuous flickering and intermittent black
rectangular artifacts.
The built-in laptop display, connected to the Intel GPU, remains completely
unaffected.
Downgrading only kwin, kwin-common, and kwin-libs from 6.8.1 to 6.8.0
completely resolves the issue, without downgrading any other Plasma components,
graphics drivers, Mesa packages, or the kernel.
This strongly suggests a regression introduced in KWin 6.8.1.
Display / GPU Topology
The DRM connector mapping is:
card0-DP-7 (card0):
0000:01:00.0 VGA compatible controller:
NVIDIA Corporation GA104M
[GeForce RTX 3070 Mobile / Max-Q] (rev a1)
card1-eDP-1 (card1):
0000:00:02.0 VGA compatible controller:
Intel Corporation TigerLake-H GT1
[UHD Graphics] (rev 01)
External monitor:** DisplayPort, driven by NVIDIA (card0-DP-7)
Built-in laptop display:** eDP, driven by Intel (card1-eDP-1)
KWin Compositor Information
The following information was collected from the working KWin 6.8.0
configuration, after downgrading:
Atomic Mode Setting on GPU 0: true
Atomic Mode Setting on GPU 1: true
compositingMode: 1
Compositing
Compositing is active
Compositing Type: OpenGL ES
OpenGL vendor string: Intel
OpenGL renderer string:
Mesa Intel(R) UHD Graphics (TGL GT1)
OpenGL platform interface: EGL
GPU class: Tiger Lake
This confirms that KWin uses the Intel GPU for OpenGL ES compositing in the
working 6.8.0 configuration, while the external DisplayPort monitor is driven
by NVIDIA.
I have not yet verified whether KWin 6.8.1 selects the same compositor GPU.
System Information
Operating System: Fedora Linux 44 (KDE Plasma)
Display Server: Wayland
Plasma Version: 6.8.1
Affected KWin Version: 6.8.1-1.fc44
Last Known Working KWin Version: 6.8.0-1.fc44
Package Source: KDE COPR repository
Integrated GPU: Intel TigerLake-H GT1 [UHD Graphics]
Discrete GPU: NVIDIA GA104M [GeForce RTX 3070 Mobile / Max-Q]
GPU Configuration: Hybrid Intel/NVIDIA, with different GPUs driving the
built-in and external displays
--
You are receiving this mail because:
You are watching all bug changes.
