VirtualBox 6.1.14 won't boot Mint (and the previous version of VirtualBox would)

[WhatHaveYou]

I can no longer boot Mint (20, x64, Cinnamon) on my Windows 10 machine. I am pretty sure i could do this before I upgraded to the latest VirtualBox version (though I have not used VirtualBox on the Windows PC for a week or so). Even in recovery mode, Mint gets stuck trying to do something - according to the boot text - to do with USB tablet (which is odd, because the host is a desktop PC). Can anyone shed light? Thanks.

[scottgus1]

Can anyone shed light?

6.1.14 just came out today, so any light would probably be dim. Unless, of course, you know, well... there's a guest vbox.log to peruse.

The USB tablet is probably the pointing device used in the guest environment. It often lets a guest have Mouse-Integration-like behavior without Guest Additions installed.

[WhatHaveYou]

More data: when trying to boot one of my Grub recovery entries, I get a hang on: 'kernel panic - not syncing: corrupted stack end detected inside scheduler.' There is some stuff on the web about that error and some of that stuff that to do with VirtualBox but none of it seems helpful.

I attach the log.

Also, just now, Vbox told me the expansion pack (curse it) was out of date. I'd installed the new one. But I told VB to install it again. It started to. Then it noticed that actually the new version was installed already. I told it to (re)install anyway. It did. I tried to boot Mint. It failed.

EDIT: thanks, scotgus.