Strange video behavior in VB

[MR ZenWiz]

On Tue, Oct 27, 2020 at 4:42 AM Liam Proven <lproven at gmail.com> wrote:
>
> On Tue, 27 Oct 2020 at 01:31, MR ZenWiz <mrzenwiz at gmail.com> wrote:
> >
:
> > I just installed Linux Mint 20 in a VB VM on my Xubuntu 20.04.1
> > desktop,
>
> You mean VirtualBox, right? I ask 'cause "VB" is the standard
> abbreviation for MS Visual Basic and from the title that's what I
> thought you meant, and I was at a loss as to what this meant on or re
> Linux until I read the message.
>
I never use or even think of Visual Basic - my mistake.

Yes, VirtualBox.

> Standalone version from www.virtualbox.org (current = 6.1.14) or the
> older version from the Ubuntu repos? (Not sure, can't check as I am
> typing on macOS.)
>
Standalone v6.1.14...

> Reboots of the host or of the guest?
>
Guest.  I only reboot the host when I update and the update requires a reboot.

> The guest doesn't know [that it's a VM]. It just sees a graphics card. You can
> pick which one under:
>
>  VBox -> VM Settings ->  Display -> Graphics controller
>
> The choices are:
> • VBoxVGA
> • VBoxSVGA (the native one)
> • VMSVGA (compatible with VMware, I believe)
> • None
>
The one that comes up by default is VMSVGA.  When I changed it to
VboxSVGA and turned off the 3D acceleration, the Mint VM works fine,
except it still can't seem to handle full screen mode or "maximized."
I expanded the window to fill the whole screen and that works fine too
- very strange.

> > I have the guest additions installed,
>
> Those *contain* graphics drivers. So you *do* have graphics drivers installed.
>
Ok...
> How did you install them? From the VBox ISO (latest but you don't get
> updates) or from the Ubuntu repos in the guest?
>
>From the built-in VB guest additions ISO that mounts on demand.

> > and I can resize the
> > screen/window, but in full screen mode, it goes blank and does not
> > appear to recover.
> >
> > Any clues?
>
> We need more info.
>
> To enable hardware passthrough, you need to do 2 primary things:
>
> [1] Enable 3D acceleration in that VM in VBox's  Display Settings
> [2] Install graphics drivers via the Guest Additions, either the ones
> VBox provides in an ISO or via those in most Linux distros' repos.
>
I tried that, in that order.  The results are as I described in my OP.

> I described it in a blog post here:
>
> https://liam-on-linux.livejournal.com/33987.html
>
I'll keep that handy, thanks.

> Notes:
> • To do much with them, you need a 3D-accelerated desktop (e.g. GNOME
> 3, Cinnamon, Unity) or to enable it under one of the desktops where
> it's optional (Maté, XFCE etc.)
I did not know that.  I hope it fits here - the Mint has Cinnamon and
the Ubuntu has GNOME 3.

> • I have had significant problems with every version of KDE I've tried
I use a few KDE utilities, but I have never liked KDE - just not my
cup of tea.  Others love it.

> • To build the kernel module, you need compilers etc install. I
> recommend installing the packages `build-essential` and `dkms` and the
> headers for your current kernel *before* you install the extensions.
> If you did not have this, remove the extensions, reboot, install DKMS,
> the kernel headers and the build essentials, reboot, install the guest
> additions, shut down the VM, enable 3D acceleration in VBox settings,
> and restart the VM.
I'm sitting in the Ubuntu VM, expanded to full screen, waiting for
something to show up.  The mouse cursor took a minute or two before it
became visible, and after five minutes of typing this response, it is
still blank (black).

I'll see what happens if I ever get anything, or reboot the VM until I
see something - anything - to work with.

Thanks.

Mark