kded4 hangs when wlan, vpn or pptp network toggled

[shoo_ash]

Frequently the kded4 hangs, consuming 50% cpu, when some network connections are disabled or reenabled. In this case plasma network manager applet also doesn't respond. Changed it to knetworkmanager - and wlan gets connected while system tray is frozen.

Seems like networkstatus kde module bug. No problems when kded4 started without this service (had to alter .desktop launcher)

ProblemType: Bug
DistroRelease: Ubuntu 11.04
Package: kdelibs-bin 4:4.6.1-0ubuntu3
ProcVersionSignature: Ubuntu 2.6.38-7.38-generic 2.6.38
Uname: Linux 2.6.38-7-generic i686
Architecture: i386
Date: Wed Mar 23 22:24:16 2011
ExecutablePath: /usr/bin/kdeinit4
InstallationMedia: Kubuntu 11.04 "Natty Narwhal" - Alpha i386 (20110307)
ProcEnviron:
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: kde4libs
UpgradeStatus: No upgrade log present (probably fresh install)
XsessionErrors:
 (knotify4:1260): GStreamer-CRITICAL **: gst_debug_add_log_function: assertion `func != NULL' failed
 (thunderbird-bin:1443): GLib-CRITICAL **: g_hash_table_insert_internal: assertion `hash_table != NULL' failed

[Jonathan Thomas (echidnaman)]

KDE's network manager has a kded plugin that's probably causing this issue.

[E.T. Anderson (firebringer11)]

More precisely, the process consumes 100% of one CPU core. I've got 4, so it shows as 25% use.

I do not experience this problem with the wireless, but I do when I disconnect from a VPN connection.

[David Matějček (dmatej)]

The same when my mobile connection goes down. I use the 64bit Natty.

[shoo_ash (ash-mail)]

Internet-surfing gave me some results.
For me this bug doesn't reproduce if kded4 starts with networkstatus module (service) turned off. This idea was suggested here: https://bugs.kde.org/show_bug.cgi?id=220047#c28
But the module was loading always even when disabled in Service Manager or via qdbus. So to turn it off completely I had to edit /usr/share/kde4/services/kded/networkstatus.desktop
$ sudo nano /usr/share/kde4/services/kded/networkstatus.desktop

There I set autoload and load-on-demand options to false:

X-KDE-Kded-autoload=false
X-KDE-Kded-load-on-demand=false

Then - unloaded the module manually
$ qdbus org.kde.kded /kded unloadModule networkstatus
and restarted kded4
$ qdbus org.kde.kded /kded quit
$ kded4 &

Now I can trigger wlan connection without problems, but without networkstatus service.

[shoo_ash (ash-mail)]

Another 5 c.: to connect without networkstatus service use KNetworkManager. plasma-widget-networkmanagement depends strictly on networkstatus.

[Jose Bernardo (bernardo-bandos)]

You mean install KNetworkManager instead of plasma-widget-networkmanagement?

[shoo_ash (ash-mail)]

> You mean install KNetworkManager instead of plasma-widget-networkmanagement?
Yes, as they are incompatible (as package manager says).

To revert if the bug gets fixed just install plasma-widget-networkmanagement back (and don't forget to turn networkstatus service on).

[Dimitri (dr-kart)]

I use Kubuntu 11.04 x32.
3G USB modem Huawei E219. System hangs when I disconnect from internet. After that I can only get to console via CTRL-ALT-F1.

[Francisco Gonzalez (gzmorell-gmail)]

This can be reproduced easily.
This happens every time you try to disconnect from networ using a gsm connection.
It can also reproduced using a virtualbox machine with a "Host-only networking" after starting the virtual machine, a network is added if you try to disconnect from plasma-widget-networkmanagement kded4 goes to 100%.