guest Linux graphical interface segfaults

[Kazoar]

Hello, this is my first post here. Here's hoping I don't waste your time...

Since a week, I have a problem with all my linux guests. After a few minutes running, the graphical interface segfaults. I have had the problem with the following machines :

VM1 : Linux debian 5.10.0-11-amd64 #1 SMP Debian 5.10.92-1 (2022-01-18) x86_64 GNU/Linux, gnome-shell 3.38.6 (started from snapshot) (guest addon installed)
VM2 : Linux debian 5.10.0-15-amd64 #1 SMP Debian 5.10.120-1 (2022-06-09) x86_64 GNU/Linux, cinnamon 4.8.6 (freshly installed) (no guest addon)
VM3 : A Fedora, didn't check the version, I just wanted to make sure this wasn't a debian problem (freshly installed)(no guest addon)

The problem arises on VM1 even after updates. It also occurs with or without the guest addon and with or without Virtualbox extension pack, I've tried all the combinations, I think...

Here is an example of errors collected by journalctl on VM1 :

Code: Select all   Expand viewCollapse view

juin 26 12:13:45 debian kernel: gnome-shell[6238]: segfault at 557d8406baf4 ip 00007fde373724ae sp 00007ffe8fe64060 error 4
juin 26 12:13:45 debian kernel: Code: c5 fe f8 c5 35 fe c0 c5 35 fe cf c5 cd fe c0 c5 c5 fe fe c5 fd 6f 33 c4 e2 6d 00 d6 c4 e2 75 00 f6 c5 f5 76 c9 c4 41 21 ef db <c4> 02 75 90 1c 02 c5 f5 76 c9 c4 41 39 ef c0 c4 42 75 90 04 02 c5

and VM2 :

Code: Select all   Expand viewCollapse view

Jun 26 05:31:49 debian kernel: cinnamon[1051]: segfault at 55daed087740 ip 00007fa0cfdde666 sp 00007ffce998f7e0 error 4
Jun 26 05:31:49 debian kernel: Code: fd fe c5 c5 65 fe cd c5 fd fe db c5 c5 fe ed c5 fd fe ff c5 fd 6f 03 c4 e2 4d 00 f0 c4 e2 75 00 c0 c5 f5 76 c9 c4 41 09 ef f6 <c4> 02 75 90 34 0a c5 f5 76 c9 c4 41 31 ef c9 c4 42 75 90 0c 2a c5

My host is a Debian too : Linux 5.10.0-15-amd64 #1 SMP Debian 5.10.120-1 (2022-06-09) x86_64 GNU/Linux
My VirtualBox version is 6.1.34-150636.1~Debian~bullseye

Given that the problem occurs on Debian and Fedora and with two desktop graphical interfaces, it feels to me that this could be a virtualbox problem. I didn't read any similar issues in the forum, has anybody run into this and has an idea of how to sort it out ?

[fth0]

The actual problem is that VirtualBox 6.1.34 and 6.1.97r150532 do not support Debian Linux kernel 5.10.120 on the host and will produce random crashes in the guest (pun intended ). See 20914 and Windows 10 Guest on Linux host dies seconds after boot for details.

The VirtualBox test builds 6.1.35r151864 (and newer) are supposed to support Linux kernels 5.18, 5.17.12+, 5.15.44+, 5.10.119+ and more on the host and in the guest.

[Kazoar]

That would explain it, I thought I had checked all the obvious answers but checking if my host actually supports the software that has a bug ? For some reason, that didn't cross my mind
I'll try the test builds, thanks for the suggestion.

[Kazoar]

I gave a try to the stable and development test builds. No luck.

The stable build (Linux 6.1.35-151866) seems to have a problem of graphical interface, I don't have any menu when I run it so I can't interact with it.
Surprisingly, the development one (Linux 6.1.97-150532) works like a charm at first, but I have the same problem than with the "normal" build.

I also added the experimental extension and guest addon but the problem persists.

[fth0]

Surprisingly, the development one (Linux 6.1.97-150532) works like a charm at first, but I have the same problem than with the "normal" build.

Well, you didn't believe me, did you?

The stable build (Linux 6.1.35-151866) seems to have a problem of graphical interface, I don't have any menu when I run it so I can't interact with it.

Did you uninstall the previously installed packages before installing the test build? Please elaborate on what you did exactly, and provide a (zipped) VBox.log file of a VM run.

[Kazoar]

Sorry for the imprecision, so, to be more precise :
- I uninstalled my current version of virtualbox through "apt remove virtualbox*". I had installed it with apt install before.

- Downloaded the file VirtualBox-6.1.35-151866-Linux_amd64.run and ran it as root. It seemed to work fine, no errors appeared. But whenever I try to run /opt/Virtualbox/virtualbox, nothing... It IS running as I see it through the ps command, but no menu show up, the command line just returns without a word. So I uninstalled it with "./VirtualBox-6.1.35-151866-Linux_amd64.run uninstall" which, as far as I know worked.

- Downloaded the file VirtualBox-6.1.97-150532-Linux_amd64.run and ran it as root. It seemed to work fine, no errors appeared. Running "/opt/Virtualbox/virtualbox", the virtualbox menu showed up without a problem. I ran VM1 and eventually ran into the segfault. I downloaded the experimental extension pack, ran again into the segfault. I installed the experimental addon on VM1, rebooted it, and ran again into the segfault.

The log I'm putting is an attempt I just tried so it's VM1, woken up from a snapshot, still with the guest addon of 6.1.32 and no extension pack installed on VirtualBox-6.1.97-150532.

[fth0]

Thanks for filling in the details. Regarding VirtualBox 6.1.35 (and 6.1.97), directly running "/opt/VirtualBox/VirtualBox" may be wrong. You're supposed to use "/usr/bin/VirtualBox" or "/usr/bin/virtualbox" ("/usr/bin" is in the path) that are linked to the wrapper script "/opt/VirtualBox/VBox.sh".

[Kazoar]

Understood, I ran the said binary and the gnome-shell process of the guest ended up crashing yet again. Here are the logs, VM1 again, with the same snapshot.

[fth0]

Of course any VM sooner or later crashes in VirtualBox 6.1.97r150532 running on your host, that's what I told you from the beginning. So why are you trying to prove that to me?

[Kazoar]

Oh my apologies, I misread you at the beginning and kept imagining that both versions 6.1.35 AND 6.1.97 could work.

Well, I'm stumped : the 6.1.35 just does not start any graphical interface so I don't really know how to interact with it. I updated my nvidia drivers to the latest version just in case but still, the crashes keep occurring... I'm checking the different logs to pinpoint why 6.1.35 does not show any graphical interface but otherwise, I'm out of ideas...

[fth0]

Downloaded the file VirtualBox-6.1.35-151866-Linux_amd64.run and ran it as root.

Did you really run it as the root user, or did you run it from your own user with sudo?

I'm checking the different logs to pinpoint why 6.1.35 does not show any graphical interface

While VirtualBox 6.1.35 is installed, start the VM from the Powered Off state (not the Saved State ), reproduce the issue, completely shut down the VM, and provide the (zipped) VBox.log file.

[Kazoar]

Did you really run it as the root user, or did you run it from your own user with sudo?

I installed it as the root user and also tried to run it as the root user.

While VirtualBox 6.1.35 is installed, start the VM

That's where my problem lies, I don't have the VirtualBox GUI at all so it's hard for me to do anything with it, like starting a VM. I had a look and just realized that VirtualBox can be controlled through the command line with vboxmanage so I'll see what I can do but so far when I run a VM through vboxmanage, I still don't have a GUI for my VM.

[fth0]

You can start a VM from within a terminal using VirtualBoxVM --startvm <VM name>.

You could provide a zip file containing the contents of the (user-specific) VirtualBox global configuration folder (/home/<username>/.config/VirtualBox or /root/.config/VirtualBox), which also contains the global log files.

[Kazoar]

Allight, so after MANY attempts to get a visual interface by trying to get a RDP session working and whatnot on my VM, I finally gave up and had a look around the forum.

This link https://forums.virtualbox.org/viewtopic.php?f=7&t=89843 allowed me to finally get a GUI on virtualbox 6.1.35 and the VMs I was running. I exported these three variables and it worked :

Code: Select all   Expand viewCollapse view

export QT_SCREEN_SCALE_FACTORS=1
export QT_SCALE_FACTOR=1
export QT_AUTO_SCREEN_SCALE_FACTOR=0

It's black magic for me really, no idea why it unlocked everything but I now have Virtualbox 6.1.35 r151866 running properly. And so far, it works like a charm ! I've been using my VM browser non stop for an hour viewing videos and it hasn't failed a single time. I guess the new version will solve my problem. I'll keep monitoring it to see if it fails again but 1 hour without segfaulting is a huge improvement so I'm hopeful.

Regardless, this graphical interface problem was a pain, I sincerely hope it will be fixed !

Since the segfaulting error is gone with Virtualbox 6.1.35, I assume you won't be needing the logs anymore, or do you want to have a look anyway ?

[fth0]

Thanks for reporting back.

The log files were only meant to help identifying the problem and aren't need any more.