Can I get more screen resolution options for a QEMU virtualized Windows using a VirtIO graphics card?

Question

When virtualizing e.g. a Windows 10 installation with QEMU and using the default graphics card (with no command line option set), it shows up as a "Microsoft Basic Display Adapter", and one can choose from a lot of resolutions:

1920 x 1200
1920 x 1080
1680 x 1050
1600 x 1200
1440 x 900
1280 x 900
1280 x 1024
1280 x 960
1280 x 800
1024 x 768
800 x 600

(on a Windows 7 VM, it's even two more).

When adding a VirtIO graphics card via

-vga virtio

or

-device virtio-vga

and installs the respective drivers, the card shows up as a "Red Hat VirtIO GPU DOD controller", and most of the options are gone:

2560 x 1600
1920 x 1080
1280 x 1024
1024 x 768
800 x 600

I also tried options like

-device virtio-vga,edid=on,xres=1440,yres=900

but that doesn't change anything. Still the same few resolutions to choose from.

Is it possible to get more resolution options for a VirtIO grahics card?

Answer 1

Quite some time, but I found a solution.

one can make QEMU's window scalable with "View" → "Zoom To Fit" and resize it to the desired size. Then, one can resinstall the Virtio drivers (mount the CD and start virtio-win-gt-x64.msi, then choose "Repair").

The current resolution will be reset, but a new option will be added which exactly matches the size of the window when re-installing the drivers.

A bit odd, but it gets the job done to view the VM inside a Window …