Bug 503717

Summary:	With NVIDIA GPU, second monitor stays black on Wayland after screen lock
Product:	[Plasma] kwin	Reporter:	dougg0k
Component:	multi-screen	Assignee:	KWin default assignee <kwin-bugs-null>
Status:	RESOLVED DUPLICATE
Severity:	normal	CC:	john.kizer, nate
Priority:	NOR	Keywords:	multiscreen, wayland-only
Version First Reported In:	6.3.4
Target Milestone:	---
Platform:	Arch Linux
OS:	Linux
Latest Commit:		Version Fixed In:
Sentry Crash Report:

Description dougg0k 2025-05-03 17:06:07 UTC

SUMMARY
After getting into screenlock due to inactivity, when you type the password to come back, the second monitor stays in blackscreen in wayland, but it works fine in x11.

I have then to turn the monitor off and back on to have the screen appear. 

Not sure if the issue is from kscreen or another component/product.

STEPS TO REPRODUCE
1. Have at least 2 monitors
2. Log In to Wayland
3. Stay afk till reach lockscreen
4. Unlock 

OBSERVED RESULT
Second monitor stays in blackscreen.

EXPECTED RESULT
To work and screen appear normally.

SOFTWARE/OS VERSIONS
Linux/KDE Plasma: Arch linux based distro
KDE Plasma Version: 6.3.4
KDE Frameworks Version: 6.13.0
Qt Version: 6.9.0

Comment 1 dougg0k 2025-05-03 17:08:25 UTC

I have a nvidia btw.

Comment 2 John Kizer 2025-05-11 04:15:27 UTC

Hi - just to check, when that second monitor is showing nothing, can you still move the cursor over to it and drag windows into it? I'm asking as this sounds like it could be an instance of https://bugs.kde.org/show_bug.cgi?id=494262 

Thanks!

Comment 3 dougg0k 2025-05-11 14:30:32 UTC

Yes, it seems possible to do so.

I also see those errors mentioned there in the logs.

kwin_wayland[3297]: kwin_core: XCB error: 3 (BadWindow), sequence: 610, resource id: 20971547, major code: 129 (SHAPE), minor code: 6 (Input)
kwin_wayland[3297]: kwin_core: XCB error: 3 (BadWindow), sequence: 636, resource id: 20971549, major code: 129 (SHAPE), minor code: 6 (Input)
systemd[3221]: dbus-:1.2-org.kde.KSplash@0.service: Failed with result 'exit-code'.
kwin_wayland[3297]: kwin_core: XCB error: 3 (BadWindow), sequence: 770, resource id: 20971557, major code: 129 (SHAPE), minor code: 6 (Input)
kwin_wayland[3297]: kwin_core: XCB error: 3 (BadWindow), sequence: 796, resource id: 20971559, major code: 129 (SHAPE), minor code: 6 (Input)
kwin_wayland[3297]: kwin_core: XCB error: 3 (BadWindow), sequence: 822, resource id: 20971561, major code: 129 (SHAPE), minor code: 6 (Input)
kwin_wayland[3297]: kwin_core: XCB error: 3 (BadWindow), sequence: 848, resource id: 20971563, major code: 129 (SHAPE), minor code: 6 (Input)
kwin_wayland[3297]: kwin_core: XCB error: 3 (BadWindow), sequence: 880, resource id: 20971565, major code: 129 (SHAPE), minor code: 6 (Input)
plasmashell[3421]: kf.plasma.quick: Exposed with no visual parent. Window positioning broken.
plasmashell[3421]: kf.plasma.quick: Exposed with no visual parent. Window positioning broken.
kwin_wayland[3297]: kwin_core: KWin::LayerShellV1Window doesn't support setting maximized state
kwin_wayland[3297]: kwin_core: KWin::LayerShellV1Window doesn't support setting fullscreen state
org_kde_powerdevil[3468]: No traced function stack for current thread
kwin_wayland[3297]: kwin_core: KWin::LayerShellV1Window doesn't support setting maximized state
kwin_wayland[3297]: kwin_core: KWin::LayerShellV1Window doesn't support setting fullscreen state
org_kde_powerdevil[3468]: [  3590] (i2c_check_open_bus_alive) Retrying i2c_check_edid_exists_by_dh() (c): Slept for 1000 millisec
org_kde_powerdevil[3468]: [  3590] /dev/i2c-3: Checking EDID succeeded after 3 tries (G)
org_kde_powerdevil[3468]: org.kde.powerdevil: [DDCutilDisplay]: ddca_get_non_table_vcp_value -5
kwin_wayland[3297]: kwin_core: KWin::LayerShellV1Window doesn't support setting maximized state
kwin_wayland[3297]: kwin_core: KWin::LayerShellV1Window doesn't support setting fullscreen state

But I suppose, the only way to make sure it's the same issue, is if the issue persist after that is fixed.

Comment 4 John Kizer 2025-05-12 16:28:03 UTC

Thanks! With the same symptoms and messages, let's merge these together for better visibility to the scope of the issue.

*** This bug has been marked as a duplicate of bug 494262 ***

Comment 5 dougg0k 2025-05-12 16:58:49 UTC

I can say that this bug has been happening for a while now, I just didnt report it before, at least not through here. So, probably unrelated to the newest kwin versions.