Bug 374802 - plasmashell use 100% cpu and eat all system memory when plug HDMI monitor (possibly infinite recursion)
Summary: plasmashell use 100% cpu and eat all system memory when plug HDMI monitor (po...
Status: RESOLVED UPSTREAM
Alias: None
Product: plasmashell
Classification: Plasma
Component: general (show other bugs)
Version: 5.8.5
Platform: Kubuntu Linux
: NOR critical
Target Milestone: 1.0
Assignee: David Edmundson
URL:
Keywords:
Depends on:
Blocks:
 
Reported: 2017-01-09 11:00 UTC by matteo.facchinetti
Modified: 2017-07-03 08:24 UTC (History)
3 users (show)

See Also:
Latest Commit:
Version Fixed In:
Sentry Crash Report:


Attachments
gdb backtrace of the plasmashell reported bug (7.23 KB, text/plain)
2017-01-09 11:00 UTC, matteo.facchinetti
Details

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Description matteo.facchinetti 2017-01-09 11:00:57 UTC
Created attachment 103303 [details]
gdb backtrace of the plasmashell reported bug

KDE on ubuntu xenial-backports repositories installed on Kubuntu 16.04

Problem appears when plug an external monitor on HDMI port.
When plug the HDMI connector, plasmashell start to eating 100% of cpu and system freeeze. No way to kill or stop plasmashell. System resources are completely busy...

I was able to debug plasmashell attaching this process and then ctrl-c when overload occurs.
After wait a lot of time that gdb response to my ctrl-c command, I see that process eat all my system memory and with backtrace seems that plasmashell enter in a infinite recursion of QQuickItem::setImplicitSize(double, double)() calls.

In attachment a piece of backtrace callstack.

Problem is repetitive and occurs each time I try to connect my monitor. If needed I can help giving more information about the bug.

I'm waiting to response.

Regards,
Matteo
Comment 1 Christoph Feck 2017-01-11 00:55:44 UTC
If this is reproducible, could you isolate which desktop widget or panel applet is responsible? You can temporarily remove those to verify.
Comment 2 David Edmundson 2017-01-11 15:28:57 UTC
Can you include all your versions of Qt, frameworks, and Plasma

Also can you try removing the pager applet and retrying; it's the one place I've seen this before so it might narrow it down.

Can you set the bug status back to unconfirmed when you reply
Comment 3 matteo.facchinetti 2017-01-16 08:14:27 UTC
KDE Plasma Versoin 5.8.5
KDE Frameworks Version: 5.28.0
QT Version: 5.6.1
Kernel Version: 4.4.0-57-generic
OS Type: 64-bit

Problem disappears only when:
- I remove the default panel on main desktop
and
- I remove all application icons placed on desktop

I don't understand how to remove the pager applet so I can't try to plug-in the hdma cable unless this applet.
Comment 4 David Edmundson 2017-02-19 15:06:15 UTC
Click the menu icon on the right of the panel (looks like an = with 3 lines) then you should see the desktop pager (if it exists) it looks like a blue square next to the K menu. click on the X in the tooltip to remove it.
Comment 5 matteo.facchinetti 2017-02-27 11:34:20 UTC
OK, thanks....

So, I do a test removing pager applet from the panel but problem remain.

I also do a test with an empty panel instead of my default panel and system continue to freeze.
Comment 6 David Edmundson 2017-05-11 13:25:26 UTC
Loop is in Qt.

Your Qt Version is 5.6.1


I'm going to close this, unless you can reproduce on a newer system.
Comment 7 Patrick Rudolph 2017-07-03 08:24:08 UTC
Please provide a reference to the upstream bug report.