Bug 346861

Summary:	windows become invisible in Virtualbox after some usage (likely invalid texture IN qml clients)
Product:	[Plasma] kwin	Reporter:	Boris Egorov <egorov>
Component:	general	Assignee:	KWin default assignee <kwin-bugs-null>
Status:	RESOLVED NOT A BUG
Severity:	normal
Priority:	NOR
Version First Reported In:	5.2.2
Target Milestone:	---
Platform:	Kubuntu
OS:	Linux
Latest Commit:		Version Fixed/Implemented In:
Sentry Crash Report:
Attachments:	screenshot screenshot after xkill kwin supportInformation

Description Boris Egorov 2015-04-28 18:23:25 UTC

After a short usage of Kubuntu 15.04 in Virtualbox, windows becomes invisible. They are opened, because sometimes you can see how cursor changes when hovers above input field/terminal. At the same time, a few things still visible: settings button in top left corner, Krunner and its submenus, Kickoff menu (not its button, it disappears with panel), window previews when you hover over invisible panel.

Reproducible: Always

Steps to Reproduce:
I'm not quite sure about exact steps to reproduce a problem, but it can be reproduced after some time of usual work after system installation. Let's say..

1. Install Kubuntu 15.04 in Virtualbox
2. Try to do some work (install virtualbox-guest-dkms and virtualbox-guest-x11, reboot, lock workspace and log in again).
3. Windows and panel is invisible

Actual Results:  
Windows and panel is invisible

Expected Results:  
Windows and panel should be visible

Comment 1 Boris Egorov 2015-04-28 18:27:12 UTC

Screenshots here: http://imgur.com/a/YsHpd

Comment 2 Thomas Lübking 2015-04-28 20:43:43 UTC

Looks like invalidated texture, please attach the output of
    qdbus org.kde.KWin /KWin supportInformation

Does it "fix" by suspending the compositor (SHIFT+Alt+F12) or does it happen with the xrender backend itfp? ("kcmshell5 kwincompositing")
(it's a virtual machine, you might just have run out of some memory quota)

Comment 3 Boris Egorov 2015-04-29 03:51:29 UTC

(In reply to Thomas Lübking from comment #2)
> Looks like invalidated texture, please attach the output of
>     qdbus org.kde.KWin /KWin supportInformation
$ qdbus org.kde /KWin supportInformation
Service 'org.kde' does not exist.

I tried to use qdbusviewer and haven't found kwin there too.
> Does it "fix" by suspending the compositor (SHIFT+Alt+F12)
No, still happens.
> or does it happen with the xrender backend itfp? ("kcmshell5 kwincompositing")
Yeah, looks like xrender backend is activated: http://i.imgur.com/YJZTqsO.png . Should I try to enable OpenGL?

Comment 4 Boris Egorov 2015-04-29 03:53:09 UTC

(In reply to Boris Egorov from comment #3)
> $ qdbus org.kde /KWin supportInformation
> Service 'org.kde' does not exist.
Same for original command:

$ qdbus org.kde.KWin /KWin supportInformation
Service 'org.kde.KWin' does not exist.

I just tried to see which services exists after it fails for the fist time.

Comment 5 Thomas Lübking 2015-04-29 08:40:22 UTC

(In reply to Boris Egorov from comment #3)

> No, still happens.
Not a bug in kwin but the particular client.
It's likely because Plasma -> QML -> OpenGL ./. virtual graphics card.

> Should I try to enable OpenGL?
No. XRender is supposed to be used in virtual machines.

> $ qdbus org.kde.KWin /KWin supportInformation
> Service 'org.kde.KWin' does not exist.

The last screenshot looks like KWin crashed (and didn't restart) - ie. there's no WM running.
Any moment spotted where this might have happened?
(You can restart it by issueing "kwin_x11" into the Alt+F2 krunner)

Comment 6 Boris Egorov 2015-05-01 08:34:05 UTC

Created attachment 92352 [details]
screenshot

I discovered that even widgets works fine. What should I do to investigate bug further? Any logs?

Comment 7 Boris Egorov 2015-05-01 08:48:07 UTC

Created attachment 92353 [details]
screenshot after xkill

One more finding: I can call xkill, click on a background, and finally see my windows. But no background, no widgets and panel anymore. KRunner works though.

Comment 8 Thomas Lübking 2015-05-01 14:00:06 UTC

You entered the desktop showing/dashboard mode . After killing the desktop, it oc. doesn't cover your windows anymore.
This is not related to your initial report where the wallpaper (or some client internal texture) was invalid, but the desktop actually present (one can see the config "burger" button)

Comment 9 Boris Egorov 2015-05-01 15:44:06 UTC

(In reply to Thomas Lübking from comment #8)
> This is not related to your initial report where the wallpaper (or some
> client internal texture) was invalid, but the desktop actually present (one
> can see the config "burger" button)
Ok, fine. How do I check if it is related with some wallpaper? Can I delete a wallpaper and try to see how plasma behaves?

Comment 10 Boris Egorov 2015-05-01 16:11:26 UTC

Created attachment 92356 [details]
kwin supportInformation

So, I killed plasmashell (to actually use konsole and see output), run 'kwin_x11 --replace' and then 'qdbus org.kde.KWin /KWin supportInformation'. Output of the last command is attached.

Comment 11 Thomas Lübking 2015-05-03 10:10:15 UTC

I don't think it's related to some wallpaper like "file on your disk", since this was reported to happen "After a short usage". The issue will rather be insufficient video memory being available to OpenGL in the virtual machine (setup) because the entire QML thing moves a lot of payload there.

Try to increase the graphics memory in the virtual machine setup.

Comment 12 Martin Flöser 2017-10-22 18:43:34 UTC

Bug in virtualbox's OpenGL driver, unrelated to KWin.