Bug 478231

Summary:	On system with nvidia dGPU, external monitor turns black with only cursor shown after suspend to ram
Product:	[Plasma] kwin	Reporter:	fanzhuyifan
Component:	general	Assignee:	KWin default assignee <kwin-bugs-null>
Status:	RESOLVED WORKSFORME
Severity:	grave	CC:	nate, postix, roman, whelanh, xaver.hugl
Priority:	NOR	Keywords:	qt6
Version First Reported In:	git master
Target Milestone:	---
Platform:	Other
OS:	Linux
Latest Commit:		Version Fixed/Implemented In:
Sentry Crash Report:
Attachments:	kwin log

Description fanzhuyifan 2023-12-07 21:55:10 UTC

SUMMARY
***
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***


STEPS TO REPRODUCE
1. connect external monitor
2. suspend to ram
3. wake again 

OBSERVED RESULT
1. external monitor is blank with only cursor shown. The cursor can be moved

EXPECTED RESULT
External monitor works.

SOFTWARE/OS VERSIONS
Operating System: Arch Linux 
KDE Plasma Version: 5.90.0
KDE Frameworks Version: 5.246.0
Qt Version: 6.6.1
Kernel Version: 6.6.4-arch1-1 (64-bit)
Graphics Platform: Wayland
Processors: 20 × 13th Gen Intel® Core™ i9-13900H
Memory: 15.2 GiB of RAM
Graphics Processor: Mesa Intel® Graphics
Manufacturer: ASUSTeK COMPUTER INC.
Product Name: ROG Zephyrus G16 GU603VV_GU603VV
System Version: 1.0

ADDITIONAL INFORMATION
System is intel iGPU+nvidia dGPU
This happens both with and without configuring nvidia PreserveVideoMemoryAllocation.
Without PreserveVideoMemoryAllocation disabled, this only seems to happen if I wait a long time after suspend.

When this happens, and I suspend the computer again, the external display typically starts working again after the next wake.

This only happens with one external display I use, and not the other one.

Possible duplicate of 477738.

Comment 1 fanzhuyifan 2024-01-29 17:44:04 UTC

Right now I don't even see the cursor -- my external display says no signal detected, entering power savings mode.

Comment 2 fanzhuyifan 2024-01-29 17:44:18 UTC

Created attachment 165325 [details]
kwin log

Comment 3 fanzhuyifan 2024-02-22 01:35:14 UTC

(In reply to fanzhuyifan from comment #1)
> Right now I don't even see the cursor -- my external display says no signal
> detected, entering power savings mode.

This also sometimes happens when the display turns off during idle, without suspending to ram.

Comment 4 Zamundaaa 2025-06-02 15:06:59 UTC

Can you still replicate the problem on Plasma 6.3?

Comment 5 Bug Janitor Service 2025-06-17 03:47:39 UTC

🐛🧹 ⚠️ 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 6 Bug Janitor Service 2025-07-02 03:47:34 UTC

🐛🧹 This bug has been in NEEDSINFO status with no change for at least 30 days. Closing as RESOLVED WORKSFORME.