Bug 411652

Summary:	General breakage with multiple monitors (affecting yakuake and spectacle)
Product:	[Plasma] kwin	Reporter:	Keziolio <keziolio123>
Component:	multi-screen	Assignee:	KWin default assignee <kwin-bugs-null>
Status:	RESOLVED UPSTREAM
Severity:	normal
Priority:	NOR
Version:	5.16.4
Target Milestone:	---
Platform:	Other
OS:	Linux
Latest Commit:		Version Fixed In:
Sentry Crash Report:
Attachments:	qdbus org.kde.KWin /KWin supportInformation xprop

Description Keziolio 2019-09-06 19:35:26 UTC

SUMMARY

Please see the video: https://youtu.be/zikzg5cDIrs
This is with xorg, mesa with amd gpu

The two major things are:
1) spectacle's "rectangular region" mode is shifted to the left, and I can't screenshot the left part of the desktop
2) yakuake doesn't show up on a monitor, or, with two monitors, it shows but with a smaller / wrong width 

This seems to also glitch part of some applications, for example QtCreator works "better" on the left monitor, on the rightmost one it tends to glitch and not update the screen / render some panels with wrong size

STEPS TO REPRODUCE
1. attach more than one monitor (tested with 2 and 3 4k monitors)
2. admire the breakage

I can reproduce this with another clean user, so it shouldn't be a configuration issue


OBSERVED RESULT
Bugs

EXPECTED RESULT
The absence of bugs

SOFTWARE/OS VERSIONS
Latest version of everything in Arch Linux, this has been going on for ages

ADDITIONAL INFORMATION

$ xrandr --listmonitors
Monitors: 3
 0: +*DisplayPort-1 3840/600x2160/340+3840+0  DisplayPort-1
 1: +DisplayPort-0 3840/607x2160/345+7680+0  DisplayPort-0
 2: +HDMI-A-1 3840/608x2160/345+0+0  HDMI-A-1

Comment 1 Vlad Zahorodnii 2019-09-06 19:50:30 UTC

Can you take screenshot of all screens when kwin is broken? Does it look good?

Comment 2 Vlad Zahorodnii 2019-09-06 19:59:06 UTC

Use this command
    qdbus org.kde.KWin /Screenshot screenshotFullscreen

Comment 3 Keziolio 2019-09-06 20:04:08 UTC

The screenshot "Full Screen (All Monitors)" in spectacle looks good, so does the qdbus command you gave me, it's not broken

Regarding the screenshots issue, it's just the "preview" thing inside spectacle that is shifted, and I can't reach the leftmost part because it's "outside" the monitors

Comment 4 Vlad Zahorodnii 2019-09-06 20:17:39 UTC

Can you reproduce this bug when full screen repaints are forced?

In order to force full screen repaints, go to compositor setting and choose "Full screen repaints" swap(tearing prevention) strategy.

Comment 5 Vlad Zahorodnii 2019-09-06 20:18:16 UTC

s/setting/settings/

Comment 6 Keziolio 2019-09-06 20:25:33 UTC

I can reproduce the bug with "Full Screen Repaints" enabled

Comment 7 Vlad Zahorodnii 2019-09-06 20:28:20 UTC

Can you reproduce the bug when compositing is suspended? (press Alt+Shift+F12 to toggle compositing)

Comment 8 Keziolio 2019-09-06 20:32:54 UTC

Yes I can, both "symptoms" persist with compositing disabled

Comment 9 Vlad Zahorodnii 2019-09-06 20:36:40 UTC

Please post xprop output of the panel when "kwin" is broken.

Comment 10 Vlad Zahorodnii 2019-09-06 20:38:16 UTC

and also output of
    qdbus org.kde.KWin /KWin supportInformation

Comment 11 Keziolio 2019-09-06 20:44:32 UTC

Created attachment 122515 [details]
qdbus org.kde.KWin /KWin supportInformation

Comment 12 Keziolio 2019-09-06 20:45:04 UTC

Created attachment 122516 [details]
xprop

Comment 13 Keziolio 2019-09-06 20:48:50 UTC

"kwin" is always broken since I can't open yakuake in the rightmost monitor, the problem is persistent


Is the issue with the panel and not with kwin? I'm confused on what does what

Comment 14 Vlad Zahorodnii 2019-09-06 20:50:44 UTC

Report this bug to amdgpu developers.

https://bugs.freedesktop.org/enter_bug.cgi?product=xorg&component=Driver/AMDgpu

Comment 15 Vlad Zahorodnii 2019-09-06 20:51:08 UTC

(In reply to Keziolio from comment #13)
> "kwin" is always broken since I can't open yakuake in the rightmost monitor,
> the problem is persistent
> 
> 
> Is the issue with the panel and not with kwin? I'm confused on what does what

kwin is not broken. Something down the stack is.

Comment 16 Keziolio 2019-09-06 20:59:41 UTC

Oh ok, thanks for the support