Arch Linux

Psi2001

Member

Registered: 2025-03-15

Posts: 17

[Solved] Kwin 6.5.4-1 causes system freezes when display turns off

Hello everyone,

I recently updated to Plasma 6.5.4-1 and have been encountering random system freezes when the screen turns off, such as when the screensaver activates. The freezes occur approximately every five to ten times the display goes to sleep.

During a freeze, I am unable to switch to another TTY. However, I’ve found that flipping my laptop screen closed and then reopening it allows the system to recover.

Checking the system logs from the previous boot, I noticed the following relevant messages:

$ journalctl -b -1

kwin_wayland[1472]: Atomic modeset test failed! Invalid argument
kwin_wayland[1472]: Setting dpms mode failed!

After downgrading kwin to version 6.5.3-2, the issue no longer occurs and the system appears to be working normally again.

----------------
It has been fixed in the updated package kwin 6.5.4-2.

Last edited by Psi2001 (2025-12-12 17:08:37)

unknown

Member

Registered: 2006-08-30

Posts: 7

Re: [Solved] Kwin 6.5.4-1 causes system freezes when display turns off

Looks like https://bugs.kde.org/show_bug.cgi?id=513151.

Last edited by unknown (2025-12-10 15:59:47)

Potomac

Member

Registered: 2011-12-25

Posts: 551

Re: [Solved] Kwin 6.5.4-1 causes system freezes when display turns off

Perhaps it's the same bug I have :

When the screen goes into standby mode : sometimes after 10 minutes I can't exit the standby mode, I have to unplug the HDMI cable from the monitor and then plug it back in to see the Plasma desktop.

I'm using an AMD RX7600 graphics card.

In journalctl I see also this message :

kwin_wayland[1662]: Atomic modeset test failed! Argument invalide

If I downgrade to Plasma 6.5.3 then the bug disapears.

Last edited by Potomac (2025-12-11 01:55:20)

amish

Member

Registered: 2014-05-10

Posts: 507

Re: [Solved] Kwin 6.5.4-1 causes system freezes when display turns off

I updated my system yesterday to Plasma 6.5.4

And from today morning noticing same problem and same error:

Dec 11 11:20:29 foo kwin_wayland[882]: Atomic modeset test failed! Invalid argument
Dec 11 11:20:29 foo kwin_wayland[882]: Setting dpms mode failed!

I do not have laptop but desktop. So solution of closing the lid and reopening is not applicable to me.

Will try unplug / replug of HDMI the next time it happens.

When issue occurs, display goes dim and kind of black and white. Mouse does not move. But keyboard Num lock can be turned on / off.

Can not switch to any tty via Ctrl-Alt-f2 or so. Will try if SSH works.

@Psi2001 and @Potomac - Did you downgrade only kwin package OR all the 6.5.4 packages that were installed?

Any workaround if anyone know?

Thank you.

Psi2001

Member

Registered: 2025-03-15

Posts: 17

Re: [Solved] Kwin 6.5.4-1 causes system freezes when display turns off

I updated my system yesterday to Plasma 6.5.4

And from today morning noticing same problem and same error:

Dec 11 11:20:29 foo kwin_wayland[882]: Atomic modeset test failed! Invalid argument
Dec 11 11:20:29 foo kwin_wayland[882]: Setting dpms mode failed!

I do not have laptop but desktop. So solution of closing the lid and reopening is not applicable to me.

Will try unplug / replug of HDMI the next time it happens.

When issue occurs, display goes dim and kind of black and white. Mouse does not move. But keyboard Num lock can be turned on / off.

Can not switch to any tty via Ctrl-Alt-f2 or so. Will try if SSH works.

@Psi2001 and @Potomac - Did you downgrade only kwin package OR all the 6.5.4 packages that were installed?

Any workaround if anyone know?

Thank you.

Hello,

I downgrade kwin ONLY. Everything seems to work fine for me.

Also, I found a easy way to reproduce this bug: lock plasma desktop and press esc to turn off the screen.

Last edited by Psi2001 (2025-12-11 07:21:56)

amish

Member

Registered: 2014-05-10

Posts: 507

Re: [Solved] Kwin 6.5.4-1 causes system freezes when display turns off

I was not able to reproduce bug using lock screen - escape sequence.

It was happening when screen would DIM / Lock on its own.

Now downgraded kwin to 6.5.3 - working fine.

rezystor

Member

Registered: 2025-12-11

Posts: 1

Re: [Solved] Kwin 6.5.4-1 causes system freezes when display turns off

I'm also affected by this, however, in my case, problem is only with one monitor (in 3 monitor setup). And it's always the middle one.

I used KDE connect to execute loginctl unlock-session (which left me with desktop on two monitors and black screen on one monitor) and then I was able to switch to TTY and back and this for some reason restored the broken monitor.
Also it didn't happen every time for me, but I was not able to find exact steps to reproduce. It sometimes happens, sometimes not. Doesn't matter if screen dims on it's own or if I press escape.

Hopefully this gets a proper fix soon, for now I downgraded kwin as suggested by other posts here.

papajoke

Member

From: france

Registered: 2014-10-10

Posts: 42

Re: [Solved] Kwin 6.5.4-1 causes system freezes when display turns off

for me fixed with new version 6.5.4-2

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LTS - Fish - Kde - intel M100 - 16Go RAM - ssd

Wild Penguin

Member

Registered: 2015-03-19

Posts: 388

Re: [Solved] Kwin 6.5.4-1 causes system freezes when display turns off

I've had a similar problem. But here the screen is frozen after waking up from power save. I can change to a VT to get out of the situation. But this will usually also crash all applications (firefox, the whole KDE Plasma shell), but not always.

It's probably the same problem but the symptoms are a bit different for some reason for some users (depending on details of the system? GPU? Display manager?).

But I will upgrade to -2 now!

[OT] As a sidenote, there are / were problems with KDE Plasma and display handling when the primary display (possibly any display, didn't test in a multi-monitor setup) goes offline. Previously (it's been over a year)  I noticed most applications will crash when disconnecting the display. This can be needed for example in LAN party -like situations, and would be a major nuisance. This might be somehow related, or maybe there are several underlying bugs interplaying with each other. Under X.Org, applications will survive; but I haven't tried recently - maybe it's fixed.

Last edited by Wild Penguin (2025-12-12 13:22:07)

Psi2001

Member

Registered: 2025-03-15

Posts: 17

Re: [Solved] Kwin 6.5.4-1 causes system freezes when display turns off

I've updated to the new version 6.5.4-2, and the issue appears to be resolved so far. I'll mark this thread as solved once I confirm it's gone.