Strange segfault for some users (1.6.4 on Ubuntu 8.04)

[baekgaard]

I have a VirtualBox installation that I have problems with. It used to run fine, but the upgrade to 8.04 apparently caused problems and could never get 1.6.2 to run properly.

The machine -- AMD X2 64 CPU -- has undergone a number of changes and upgrades (HW and SW) and is currently running VirtualBox 1.6.4 on Ubuntu 8.04 w/latest upgrades installed.

This combination should in theory work...

However, whenever I start VirtualBox and try to start a VM, it immediately goes to the "Aborted" state and dmesg logs an error:

VirtualBox[10346]: segfault at 00000014 eip b79f380c esp bff602c8 error 4

This happens whether I start an old VM or try to run a new "empty" VM.

I have tried to delete (or actually rename/move) the .VirtualBox directory to make it start up completely fresh, but I still have the same problem.

However, if I log in as an other user, it works as expected...

Furthermore, I've found that I can also use VBoxSDL to the VMs run as expected, so some setting in my Qt(?) environment might be broken. VBoxVRDP also seems to work correctly.


Now I'm a bit short on ideas as to what could be causing this problem...


Any hints as to how I can further debug this problem. Can I make VirtualBox print debug messages somehow?

I'm using the Sun version, if that matters.


-- Per.

[Sasquatch]

The possibly easiest way is to let Ubuntu create a new Home folder for you. Empty it (move it to a different folder) and log in. Do this as root from a TTY and make sure you aren't logged on at the GUI.

Other than that, you can dig through your home folder and clear settings one at a time.

[baekgaard]

The possibly easiest way is to let Ubuntu create a new Home folder for you.

Well... that is essentially what I did (used an otherwise empty/newly created user for the purpose).

I could then start adding back the settings I normally use, incl. windows decorators and managers etc until it fails again -- but instead of doing this randomly I'm hoping someone may have a clue as to either 1) what settings could likely cause this, or at least 2) some way of enabling more logging/debugging that could then give me a clue as to what to look for. Just knowing whether it had to do with creating the window or the menues or whatever might be helpful.

Any further ideas or known problems interworking? Compiz can be used safely with the "new" user. Disabling emerald doesn't cause any changes either... so?

Thanks for the help and hints otherwise,


-- Per.

[Sasquatch]

And suddenly you're glad that they forgot to disable the additional loggin in 1.6.4 release. See your home folder for some logs. They may prove helpful. You could try your .config folder first, see if there is an error there.

[baekgaard]

And suddenly you're glad that they forgot to disable the additional loggin in 1.6.4 release. See your home folder for some logs. They may prove helpful. You could try your .config folder first, see if there is an error there.

No log files from VirtualBox. VBoxSDL etc leaves some, but they work fine anyway.

Renaming the entire .config folder doesn't help, it appears (have tested by logging out and in again).

;-(


-- Per.

[baekgaard]

... well, at least I could make it do a core dump, so I've mailed that off to Frank, as instructed elsewhere.

Further ideas more than welcome still


-- Per.

[Sasquatch]

Well, just continue, one folder at a time. If you find the right folder, look deeper. Did you try your .virtualbox folder too? Create the VM again. Try it with a LiveCD first .

[baekgaard]

Well, just continue, one folder at a time. If you find the right folder, look deeper. Did you try your .virtualbox folder too? Create the VM again. Try it with a LiveCD first .

Yeah, looks like this may have to be the approach ;-(

First thing I removed was the .VirtualBox folder -- no help there.

It actually crashes even before the VM gets started, so I take it must have to do with creating the initial window to host the VM or some such. I can basically create any dummy VM and start that and still have the segfault.

Thanks,


-- Per.

[baekgaard]

For the record:

Thanks to Frank, the problem has been identified to (at least partly) be caused by the Qt theme in use. Selecting another theme in qtconfig looks like it fixes the problem and allows VirtualBox to run normally.

It does appear, though, to be a combination of the theme and some other settings, since selecting the same works for another user.

But for now, the problem appears to be gone and I can run VirtualBox normally again


-- Per.