Bug 342049

Summary:	kde systemsettings uses 100% CPU
Product:	[Applications] systemsettings	Reporter:	James Ring <sjr>
Component:	kcm_autostart	Assignee:	Laurent Montel <montel>
Status:	RESOLVED FIXED
Severity:	normal	CC:	aacid, kaeslaek, kde, sjr
Priority:	NOR
Version:	4.11.10
Target Milestone:	---
Platform:	Ubuntu
OS:	Other
Latest Commit:		Version Fixed In:
Sentry Crash Report:

Description James Ring 2014-12-20 15:49:57 UTC

(copied from https://bugs.launchpad.net/ubuntu/+source/ubuntu-system-settings/+bug/1404352)

Using systemsettings 4:4.11.11-0ubuntu0.2:

When I add a new startup program to KDE, systemsettings eats 100% CPU. I can reproduce this every time with the following steps:

Go into System Settings > Startup and Shutdown > Autostart > Add program

In my case, I select /usr/bin/synergy and click OK. At this point, systemsettings process will eat 100% CPU. A strace gives the following:

write(3, "\1\0\0\0\0\0\0\0", 8) = 8

about a bajillion times. Following is a listing of the process' /proc/<pid>/fd directory:

$ ls -l /proc/6883/fd
total 0
lr-x------ 1 sjr eng 64 Dec 19 10:36 0 -> pipe:[36877]
lrwx------ 1 sjr eng 64 Dec 19 10:36 1 -> /dev/pts/14
lr-x------ 1 sjr eng 64 Dec 19 10:36 10 -> anon_inode:inotify
lrwx------ 1 sjr eng 64 Dec 19 10:36 11 -> socket:[16910389]
lr-x------ 1 sjr eng 64 Dec 19 10:36 12 -> anon_inode:inotify
lrwx------ 1 sjr eng 64 Dec 19 10:36 13 -> socket:[16910390]
lrwx------ 1 sjr eng 64 Dec 19 10:36 14 -> anon_inode:[eventfd]
lr-x------ 1 sjr eng 64 Dec 19 10:36 15 -> anon_inode:inotify
lrwx------ 1 sjr eng 64 Dec 19 10:36 16 -> anon_inode:[eventfd]
lrwx------ 1 sjr eng 64 Dec 19 10:36 18 -> socket:[16901905]
lrwx------ 1 sjr eng 64 Dec 19 10:36 2 -> /dev/pts/14
lrwx------ 1 sjr eng 64 Dec 19 10:36 27 -> anon_inode:[eventfd]
lrwx------ 1 sjr eng 64 Dec 19 10:36 3 -> anon_inode:[eventfd]
lr-x------ 1 sjr eng 64 Dec 19 10:36 4 -> pipe:[16910379]
lrwx------ 1 sjr eng 64 Dec 19 10:36 5 -> socket:[16905452]
l-wx------ 1 sjr eng 64 Dec 19 10:36 6 -> pipe:[16910379]
lrwx------ 1 sjr eng 64 Dec 19 10:36 7 -> socket:[16910380]
lrwx------ 1 sjr eng 64 Dec 19 10:36 8 -> socket:[16910384]
lr-x------ 1 sjr eng 64 Dec 19 10:36 9 -> /var/tmp/kdecache-sjr/ksycoca4

$ lsb_release -rd
Description: Ubuntu 14.04 LTS (upgraded from: Ubuntu 12.04 LTS (upgraded from: Ubuntu 10.04.2 LTS))
Release: 14.04


Reproducible: Always

Steps to Reproduce:
1. Go into System Settings > Startup and Shutdown > Autostart > Add program
2. In my case, I select /usr/bin/synergy and click OK.

Actual Results:  
systemsettings eats 100% CPU

Expected Results:  
should have added a new startup program

According to one report at https://bugs.launchpad.net/ubuntu/+source/ubuntu-system-settings/+bug/1404352 this is not limited to Ubuntu nor the particular version I'm using.

Comment 1 kaeslaek 2014-12-21 16:52:03 UTC

So that I can subscribe here too and I have the same error but with a 4.14.3 in Fedora:

I'm on Fedora 21 with KDE 4.14.3 and have the same strace output when opening the first tab in systemsettings - touchpad - touchpad (mouse click emulation page). 100% is rasing up to 100% and I can only kill it from the command line.

KDE 4.14.3
Fedora 21
Dell M4500 notebook

Comment 2 Albert Astals Cid 2015-01-05 19:24:53 UTC

Does it only happen with /usr/bin/synergy ?

Comment 3 James Ring 2015-01-13 16:27:30 UTC

I tried a few other binaries in /usr/bin with the same effect, so it's probably not specific to synergy.

Comment 4 Albert Astals Cid 2015-01-17 00:07:35 UTC

Works here, do you get the "Properties for binaryname.desktop" after clicking ok on the "Choose application" dialog?

Comment 5 James Ring 2015-01-17 00:12:38 UTC

After some time (maybe a minute), I get a "Properties for applnk" window. At this point, systemsettings stops using 100% CPU.

Comment 6 James Ring 2015-04-29 15:24:04 UTC

FWIW I cannot reproduce this with systemsettings 5.2.2-0ubuntu1 with Ubuntu 15.04 and Plasma.

Comment 7 David Edmundson 2015-04-29 22:57:11 UTC

Cool, let us know if it comes back.