Bug 501207

Summary: Monitor black and shows no signal when attempting to wake after a screen turns off automatically
Product: [Plasma] kwin Reporter: gigastarcraft2
Component: generalAssignee: KWin default assignee <kwin-bugs-null>
Status: NEEDSINFO WAITINGFORINFO    
Severity: normal CC: john.kizer, kdedev, nate, spamless.9v5xj, victorr2007, xaver.hugl
Priority: NOR    
Version First Reported In: 6.3.2   
Target Milestone: ---   
Platform: Other   
OS: Linux   
See Also: https://bugs.kde.org/show_bug.cgi?id=497465
Latest Commit: Version Fixed/Implemented In:
Sentry Crash Report:
Bug Depends on:    
Bug Blocks: 506893    

Description gigastarcraft2 2025-03-07 23:35:39 UTC
SUMMARY
System does not go back up after a screen turns off. 

STEPS TO REPRODUCE
1. Log out.
2. Wait for a screen to turn off.
3. Move a mouse or type any key on a keyboard.

OBSERVED RESULT
Black screen, monitor shows a message: "No Signal."

EXPECTED RESULT
System goes back online as it should after a mouse/keyboard activity.

SOFTWARE/OS VERSIONS
Linux/KDE Plasma: 6.13.5
KDE Plasma Version: 6.3.2
KDE Frameworks Version: 6.11.0
Qt Version: 6.8.2

ADDITIONAL INFORMATION
Comment 1 Victor Ryzhykh 2025-03-12 19:13:15 UTC
Sometimes, when the monitor's energy saving is activated, the screen no longer responds to mouse or keyboard actions. Only disconnecting the computer from the network helps. Not often, but sometimes I encounter this.
Comment 2 Victor Ryzhykh 2025-03-16 11:35:39 UTC

(In reply to gigastarcraft2 from comment #0)
> SUMMARY
> System does not go back up after a screen turns off. 
> 
> STEPS TO REPRODUCE
> 1. Log out.
> 2. Wait for a screen to turn off.
> 3. Move a mouse or type any key on a keyboard.
> 
> OBSERVED RESULT
> Black screen, monitor shows a message: "No Signal."

After trying to figure it out, I managed to fix it
after deleting the maliit-keyboard package and the file
/etc/sddm.conf.d/plasma-wayland.conf.
If the system uses only a wayland session,
then there are no crashes or black screen issues at all
after exiting the session.
But if the system uses a wayland session and an x11 session,
then when exiting the session, it happens that instead of
the login screen, there is just a black screen.
The problems started after the release of plasma-6.3.x.
After deleting maliit-keyboard and maliit,
as well as the file /etc/sddm.conf.d/plasma-wayland.conf,
I no longer see a black screen after exiting the session.
Comment 3 John Kizer 2025-03-28 02:56:26 UTC
Hi - just to check, is this issue happening at the SDDM screen, where you're sent immediately after logging out and where you'd choose which user to log in as next?

I'm double-checking that it's related to that screen, and not the "lockscreen" that's used when you haven't actually logged out of your user session, but either enough time has passed or you've manually locked your device.

Thanks!
Comment 4 Victor Ryzhykh 2025-03-28 09:03:22 UTC
(In reply to John Kizer from comment #3)
> Hi - just to check, is this issue happening at the SDDM screen, where you're
> sent immediately after logging out and where you'd choose which user to log
> in as next?

Yes, exactly on the SDDM screen, immediately after logging out.
In my case, there is also nvidia-570.
But it seems the error was fixed with the latest commits in https://invent.kde.org/plasma/kwin.
I don't encounter this error anymore.
At first I switched completely to wayland and did not receive this error, since it only 
appeared for me if two sessions were available, wayland and x11.
Recently, I installed the package again for testing, which contains files
/usr/bin/startplasma-x11
and
/usr/share/xsessions/plasmax11.desktop.
But I was never able to recreate the error again.
The black screen never appeared.
Comment 5 John Kizer 2025-03-28 17:11:25 UTC
Glad it's working for you now!
Comment 6 gigastarcraft2 2025-04-05 16:43:33 UTC
I still have the same issue but it looks like time required for the bug to show up takes more minutes.
Comment 7 Zamundaaa 2025-10-17 14:02:54 UTC
Please get the output of drm_info when the display wrongly doesn't turn on. You can run it from ssh
Comment 8 Bug Janitor Service 2025-11-01 03:47:59 UTC
๐Ÿ›๐Ÿงน โš ๏ธ This bug has been in NEEDSINFO status with no change for at least 15 days. Please provide the requested information, then set the bug status to REPORTED. If there is no change for at least 30 days, it will be automatically closed as RESOLVED WORKSFORME.

For more information about our bug triaging procedures, please read https://community.kde.org/Guidelines_and_HOWTOs/Bug_triaging.

Thank you for helping us make KDE software even better for everyone!
Comment 9 gigastarcraft2 2025-11-02 22:27:38 UTC
Since 6.5.0 update I haven't noticed this bug, however I tested only once since I disabled the option. I turned it on and I will inform in a few days/weeks.
Comment 10 gigastarcraft2 2025-11-05 01:31:50 UTC
(In reply to gigastarcraft2 from comment #9)
> Since 6.5.0 update I haven't noticed this bug, however I tested only once
> since I disabled the option. I turned it on and I will inform in a few
> days/weeks.

The bug still persists. Immediately and about 1 minute after screen turns off I am able to 'recover' screen but approximately after 5 minutes I am unable to 'recover' a screen. This is irrelevant of the "Turn off screen" setting. I cannot issue any command (even tty) when a monitor blacks out.
Comment 11 TraceyC 2025-11-05 16:12:00 UTC
(In reply to gigastarcraft2 from comment #10)
> The bug still persists. Immediately and about 1 minute after screen turns
> off I am able to 'recover' screen but approximately after 5 minutes I am
> unable to 'recover' a screen. This is irrelevant of the "Turn off screen"
> setting. I cannot issue any command (even tty) when a monitor blacks out.

Can you send us the information that Zamundaaa asked for? Please get the output of drm_info when the bug prevents the display from turning on.
Comment 12 gigastarcraft2 2025-11-06 00:08:55 UTC
(In reply to TraceyC from comment #11)
> (In reply to gigastarcraft2 from comment #10)
> > The bug still persists. Immediately and about 1 minute after screen turns
> > off I am able to 'recover' screen but approximately after 5 minutes I am
> > unable to 'recover' a screen. This is irrelevant of the "Turn off screen"
> > setting. I cannot issue any command (even tty) when a monitor blacks out.
> 
> Can you send us the information that Zamundaaa asked for? Please get the
> output of drm_info when the bug prevents the display from turning on.

> I cannot issue any command (even tty) when a monitor blacks out.
I tried and it looks like this bug prevents from issuing any command.
Comment 13 Zamundaaa 2025-11-06 17:39:50 UTC
You can log in through ssh and get it that way.