Black screen in Mint guest after login

[TheSaltydog]

I am running VBox 6.1 on MacOS host. After updating the VB Guest Additions, every time I launch my Linux Mint 19 guest it boots up until the login screen and - after authentication - it doesn't show the display, but only a black screen. The machine is still running and I can shutdown with ACPI. Tried different memory configurations, but it doesn't change.

Attaching log (compressed, as it was 150KB).

Thanks for any help.

[TheSaltydog]

.

[ftolead]

This sounds like the same issue I'm having, both guests are Ubuntu based:

Windows 10 Enterprise Host running VBox Version 6.1.8 r137981

This happens with both:
Mint 19.3 Guest running matching guest additions
and
Kubuntu 20.04 Guest running matching guest additions
128MB Video Memory
VMSVGA with 3D enabled

After first power on, the Full Screen login window displays fine. However once logged in the screen is blank, except for the mouse cursor. Once I hit Host-F to drop from Full Screen the Desktop then displays. If I hit Host-F to go back to Full Screen again, the desktop continues to display properly.

This doesn't happen when I restart the guest. Only after initial power on and boot.

[TheSaltydog]

Yes, this is exactly the same as my behaviour.

[arQon]

I have SOME VMs where this was fixed with 6.1.10, and others that are still broken. At the very least, try 6.1.10 and see if you get lucky.

[scottgus1]

In the Salty Dog's logged case, there is too little memory available:

00:00:03.192657 Host RAM: 4096MB (4.0GB) total, 1430MB available
00:00:03.377195 RamSize <integer> = 0x0000000090200000 (2 418 016 256, 2 306 MB, 2.2 GB)

I don't see anything else in the log to indicate a problem, though. The guest OS boots and loads Guest Additions.
Try a host reboot to clear memory.