Bug 272248 - knetworkmanager - system hangs when using VPN or broadband connection
Summary: knetworkmanager - system hangs when using VPN or broadband connection
Status: RESOLVED DUPLICATE of bug 270152
Alias: None
Product: Network Management
Classification: Miscellaneous
Component: general (show other bugs)
Version: unspecified
Platform: Ubuntu Linux
: NOR major
Target Milestone: ---
Assignee: Will Stephenson
URL:
Keywords:
Depends on:
Blocks:
 
Reported: 2011-05-02 15:44 UTC by Dario
Modified: 2011-05-09 06:17 UTC (History)
1 user (show)

See Also:
Latest Commit:
Version Fixed In:


Attachments
printscreen with marked buttons (59.04 KB, image/png)
2011-05-03 13:59 UTC, Dario
Details
.xsession-errors file (23.21 KB, application/octet-stream)
2011-05-03 14:32 UTC, Dario
Details
.xsession-errors file with debuging enabled (40.40 KB, application/octet-stream)
2011-05-03 14:56 UTC, Dario
Details
.xsession-errors file (80.17 KB, application/octet-stream)
2011-05-03 15:46 UTC, Dario
Details
.xsession-errors file (111.54 KB, application/octet-stream)
2011-05-03 15:53 UTC, Dario
Details
log (31.13 KB, text/x-log)
2011-05-04 11:12 UTC, Dario
Details
log (337.46 KB, text/x-log)
2011-05-04 11:12 UTC, Dario
Details

Note You need to log in before you can comment on or make changes to this bug.
Description Dario 2011-05-02 15:44:22 UTC
Version:           unspecified (using KDE 4.6.2) 
OS:                Linux

Whole system hangs when disconnecting from network, if VPN was used.

After running top in console we can se 100% CPU on KDED$ process !!
 PID USER      PR  NI  VIRT  RES  SHR S %CPU %MEM    TIME+  COMMAND                                                                                  
 3322 dario     20   0  179m  30m  21m R  100  0.8   1:57.79 kded4                                                                                             
  908 root      20   0  114m  35m 7612 S    4  0.9   4:50.86 Xorg    

Reproducible: Always

Steps to Reproduce:
1. connect to the network
2. connect to VPN network
3. disconnect from one of those networks.
Comment 1 Dario 2011-05-02 18:48:46 UTC
the same with broadband connection
Comment 2 Lamarque V. Souza 2011-05-03 01:27:17 UTC
This my be a duplicate of http://bugs.kde.org/253606

I sometimes test a VPNC type connection in Plasma NM and have never seen the system hanging because of that. Do you use the monolithic knetworkmanager or the plasmoid version? Which VPN type and options do you use?
Comment 3 Dario 2011-05-03 13:59:10 UTC
Created attachment 59571 [details]
printscreen with marked buttons

I'm not sure if this bug is a duplicate, but maybe.
My problem exists only when connecting and disconnecting from the networks, not just after startup.

It doesn't matter what kind of VPN connection it is (in my case it is pptp, but I've also test broadband connection - the same problem).

I guess that I'm using the plasmoid version (which is in the tray).
I attach a printscreen with marked buttons that I use to disconnect before KDE hangs.
Comment 4 Lamarque V. Souza 2011-05-03 14:20:03 UTC
That is the plasmoid version. Can you send me your ~/.xsession-errors file? That file is recreated everytime you logs in in KDE through kdm, so if you could not use the desktop after the problem happens you would have to log in through console (press Ctrl+Alt+F1) to copy the file and return to the graphical interface (usually by pressing Ctrl+Alt+F7).
Comment 5 Dario 2011-05-03 14:32:38 UTC
Created attachment 59572 [details]
.xsession-errors file
Comment 6 Lamarque V. Souza 2011-05-03 14:44:12 UTC
Most debugging messages are disabled in your KDE configuration. Please launch kdebugdialog program, search for "kded", tick the kded4 and kded entries, search again for "network management" and tick all entries found, log out and login again, and test again.
Comment 7 Dario 2011-05-03 14:56:13 UTC
Created attachment 59575 [details]
.xsession-errors file with debuging enabled
Comment 8 Lamarque V. Souza 2011-05-03 15:24:08 UTC
The log contains only the usual messages, nothing that could help solve your problem :-(
Comment 9 Dario 2011-05-03 15:46:14 UTC
Created attachment 59577 [details]
.xsession-errors file

OK, I've tried to do it again. 
So you can check if there is more in the new log in the new attachment.

I will also try to find out if the problem exist on other distro.
Comment 10 Dario 2011-05-03 15:53:02 UTC
Created attachment 59578 [details]
.xsession-errors file

ok check this file, not the last one which I put by mistake.
Comment 11 Dario 2011-05-03 19:29:21 UTC
OK, I've checked this on new OpenSuse 11.4 and unfortunately I have not reproduce this problem. So looks like ubuntu bug ? 
Does the last .xsession-errors contains some more informations ?
Comment 12 Lamarque V. Souza 2011-05-04 05:59:20 UTC
No, still no usefull information. Another tool you could use to test is valgrind, but it is not user friendly and it is a little messy to run kded4 through valgind. If you want to try it be warned that it can really slow down kded4.

Valgrind is a memory checker, it tries to find memory leaks and I am using it to find bugs in some programs too.

The steps are the follow:

1. Logout KDE
2. Login in a "failsafe" session (a session with only a xterm program running).
3. Start a second xterm in background: xterm &
4. Start kded4 throught valgrind in the second xterm: 

valgrind -v --leak-check=full --log-file=kded4.log --malloc-fill=0xaa --free-fill=0xbb kded4 --dograb --nocrashhandler --nofork

5. Start the rest of the KDE session in the first xterm:

startkde

6. Try to reproduce the bug.
7. Send me the file kded4.log.
Comment 13 Dario 2011-05-04 11:12:11 UTC
Created attachment 59605 [details]
log
Comment 14 Dario 2011-05-04 11:12:38 UTC
Created attachment 59606 [details]
log
Comment 15 Lamarque V. Souza 2011-05-04 13:18:22 UTC
The lines bellow "4 errors in context 1 of 270:" indicates some potential errors. Also you are using an old libpng (/lib/i386-linux-gnu/libpng12.so.0.44.0) that I know has some problems. I use libpng14.so.14.5.0 in my system.

The real error is in /lib/i386-linux-gnu/libz.so.1.2.3.4, which is using a unitialized variable in a "if". That is a programming error, a common error by the way, but that may not cause the kded4 problem you are facing. The libz in my system (libzip.so.2.1.0) is also newer then yours.

Could you try to update your libpng and libz packages?
Comment 16 Dario 2011-05-04 22:27:07 UTC
found this on launchpad, looks similar 
https://bugs.launchpad.net/ubuntu/+source/kde4libs/+bug/333944
Comment 17 Lamarque V. Souza 2011-05-04 23:25:30 UTC
Yes, it is similar and also similar to http://bugs.kde.org/253606
Comment 18 Lamarque V. Souza 2011-05-09 06:17:59 UTC

*** This bug has been marked as a duplicate of bug 270152 ***