7.0.6 fails full 4k screen with ubuntu 18.04 guest

[James2023]

Hi Virtualbox!

Just upgraded from 6.1.40-154048 to 7.0.6 (as recommended!), and now my Ubuntu 18.04 guest wont go full screen (4k). I start it in a window, login and then click maximise in virtual box and it kills my X session and drops me back to the Ubuntu GUI login screen.

It was working last week on the old version.

Host is windows 11.

Have installed the latest guest additions CD.

Guest is using VMSVGA controller with 3D and 128MB memory on one monitor (no change to before upgade).

Can't seem to capture any logs as it seems to throw them away.

Cheers for any help!

James

[scottgus1]

Can't seem to capture any logs as it seems to throw them away.

The log from Virtualbox shouldn't be deleted if the VM is doing what you describe.

Start the VM from full normal shutdown, not save-state. Run until you see the problem happen, then shut down the VM from within the VM's OS if possible. If not possible, close the Virtualbox window for the VM with the Power Off option set.

Right-click the VM in the main Virtualbox window's VM list, choose Show in Explorer/Finder/File Manager. In the "Logs" subfolder, zip the VM's "vbox.log", and post the zip file, using the forum's Upload Attachment tab. (Configure your host OS to show all extensions so you can find the "vbox.log", not "vbox.log.1", etc.)

[James2023]

Hi scottgus1.

see attached log.

Log is VM started, it briefly dropped me into my logged in home screen (at full screen res (4k)), and then dumped me back to the Ubuntu 18.04 login screen.

Fix is to reduce resolution to perhaps 1/4 of the 4k screen and then it works fine. as soon as screen is enlarged or maximized it drops me back to the login screen.

It wasn't doing this before the VirtualBox upgrade.

Thanks for your help

James

[scottgus1]

Just upgraded from 6.1.40-154048 to 7.0.6 (as recommended!)

No it isn't. That "recommended" is a user-interpreted stretch. The actual text of the Update box says the new version is there and how to download it, but it does not say the update is "recommended".

It wasn't doing this before the VirtualBox upgrade.

7.0 is still in bug-hunt phase, and graphics had a code change.

Everything seems configured about as best as it can be for graphics on this VM, including max video RAM and 3D acceleration, and up-to-date 7.0 Guest Additions.

It's an Ubuntu VM. I'd try seeing if the VM OS can use X instead of Wayland for a test.

If using X does not knock loose the proper function, please try going back to 6.1.42 Virtualbox, Extension Pack and Guest Additions.

[James2023]

Hi scottgus1,

Re "as recommended" - seem like I stuck a nerve, this wasn't my intent. When software says to upgrade, I upgrade, hence the upgrade is recommended by the vendor. I would think this is a common understanding, maybe I'm way off.

Happy to downgrade to fix the issue.

Thanks for your help.

James

[scottgus1]

seem like I stuck a nerve

No, just clarifying what's actually in the Update Available popup.

When software says to upgrade, I upgrade

This is not really a good idea, unless you're testing the new version on a test platform. New versions can bring new bugs.

I would think this is a common understanding, maybe I'm way off.

Depends on who you talk to. To some experienced computer gurus, updating on new version release is very not the thing to do. One is wise to study the new release, see what it does and what bugs are reported. "If it ain't broke don't fix it" is a wise paradigm to follow.

Other like being on the bleeding edge, and suffer the slings and arrows of outrageous fortune in doing so. It's all how you want to roll.