Bug 466607

Summary:	Bug re-introduced as of today's updates
Product:	[KDE Neon] neon	Reporter:	Chris <cjdl01>
Component:	general	Assignee:	Neon Bugs <neon-bugs>
Status:	RESOLVED FIXED
Severity:	normal	CC:	carlosd.kde, jr, neon-bugs, sitter, stuartksmith
Priority:	NOR
Version First Reported In:	unspecified
Target Milestone:	---
Platform:	Other
OS:	Linux
Latest Commit:		Version Fixed In:
Sentry Crash Report:

Description Chris 2023-02-28 16:06:12 UTC

SUMMARY
***
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***

Same issue as: https://bugs.kde.org/show_bug.cgi?id=353975

You said to open a new thread... I'm doing that.

When 5.27 came out, it didn't fully fix the issue, it had horrible problems of recuperating after a screen blanking -- had to reboot because my screens would not come up. I turned off screen blanking, and it was again stable... for about 2 weeks. After applying updates today (mostly nvidia-related), the same problem is back... black screen

STEPS TO REPRODUCE
1. Boot to KDE neon.

OBSERVED RESULT
Only one monitor is in use... the weird thing is, that the boot sequence can happen on one monitor, then when KDE comes up, the other monitor is the one KDE uses, and the one that was just working .25 seconds ago is black, and unrecoverable.

Go to "configure display settings" and you keep getting: "A new output has been removed. Settings have been reloaded" (wait 2 seconds, then) "A new output has been added. Settings have been reloaded." Looping, endlessly.

This is almost identical to the bug I mentioned above -- except even more debilitating.

EXPECTED RESULT
I expect both monitors to work.

SOFTWARE/OS VERSIONS
Windows: -
macOS: -
Linux/KDE Plasma: 5.27.1
(available in About System)
KDE Plasma Version: 5.27
KDE Frameworks Version: 5.103.0
Qt Version: 5.15.8

ADDITIONAL INFORMATION
03:00.0 VGA compatible controller: NVIDIA Corporation TU104GL [Quadro RTX 5000] (rev a1)
03:00.1 Audio device: NVIDIA Corporation TU104 HD Audio Controller (rev a1)
03:00.2 USB controller: NVIDIA Corporation TU104 USB 3.1 Host Controller (rev a1)
03:00.3 Serial bus controller: NVIDIA Corporation TU104 USB Type-C UCSI Controller (rev a1)

I've wiped my kde settings a 1000 times over now, and have rebuilt my profile from scratch...

Comment 1 Chris 2023-03-14 12:10:25 UTC

I had restored from a previous backup, and confirmed that the system worked.  That update definitely broke things again.

I waited about 7 days, did my update, and it worked fine.

Another week later... (yesterday) I installed my updates, and this bug was reintroduced again (that is twice now since 5.27).  I lost one monitor (as soon as I log into KDE... it works fine until then), the I get the infinite loop:

"A new output has been removed. Settings have been reloaded" (wait 2 seconds, then) "A new output has been added. Settings have been reloaded."

I don't know how to get a text dump from discover on the packages from Discover, I'd enumerate what was being updated, but there are too many to type by hand.

Comment 2 Chris 2023-03-14 12:11:06 UTC

I should add that I restored from the previous night's backups, and my monitors work normally again.  It is definitely related to something being updated.

Comment 3 Carlos De Maine 2023-03-15 22:15:23 UTC

that sounds more like a bug/regression in kscreen as nothing has changed in the packaging side of things.  the nvidia proprietary drivers are notorious for making incompatible changes at a whim.

Comment 4 Chris 2023-03-16 20:17:59 UTC

A regression, maybe.  But there were no nvidia updates this last round.  I'm still sitting on several dozen updates, afraid to apply them.  All I know is  it works, I apply the updates, and breaks.  Sounds like whatever it is, even if it is nvidia, kscreen will need to adapt.  

The curios thing here is that I have nvidia drivers at home on 4 different pc's and this did not happen.  It only happens Quadro, with dual (same model) monitors.  The other systems all have dual monitors, but they are not matched... I don't know if that is significant or not.

Comment 5 Stuart K. Smith 2023-06-05 20:31:58 UTC

Seeing the same thing here when kscreen is installed. AMD RX580 and KDEneon

Comment 6 Chris 2024-01-31 18:48:01 UTC

Updated system on 1/28/24... this bug was re-introduced.  Had to restore from previous backup and hold off on applying update.

Comment 7 Chris 2024-02-12 15:50:01 UTC

Updated on 2/12/24... bug seems to have been corrected.

Comment 8 Chris 2024-03-14 17:41:55 UTC

re-introduced again, as of today's updates.