nested virtualization : qemu-system-x86_64 -enable-kvm sent guest in to guru meditation (VERR_PGM_MAPPING_IPE)

[mahouk]

Hello,
I hope to find some help here. My setup is as follows:

- CPU: Intel(R) Core(TM) i7-8665U
- Guest: Ubuntu 18.04, kernel 5.4.0-150-generic
- Host: Ubuntu 22.04, kernel 6.2.0-36-generic
Virtualbox 7.0.10, nested virtualization enabled (as seen in the image)

Screenshot from 2023-11-17 19-18-22.png (41.28 KiB) Viewed 994 times

I want to use qemu inside my Ubuntu guest system.
So it's like this: Ubutun 22 VirtualBox [ Ubuntu 18 qemu [ Custom OS ] ] ]

When i use qemu with the flag -enable-kvm VirtualBox crashes, I don't really understand why, as nested Virtualization should be possible with my Version of VirtualBox, right?
Using qemu without the flag -enable-kvm naturally seems to work.
Kindly find the log file attached,

[fth0]

The VERR_PGM_MAPPING_IPE error indicates a failure in the Nested VMX/EPT (*) implementation, which is new in VirtualBox 7.0 and still being worked on for VirtualBox 7.1. Please try VirtualBox 7.0.12 first, and if the error persists, create a ticket in the Bugtracker.

(*) Note that the Nested VMX/EPT implementation in VirtualBox 7.0/7.1 is different from the Nested VT-x/AMD-V implementation in VirtualBox 6.1. It fully provides VMX and EPT to the guest OS, which is needed to enable Windows guests to run the Hyper-V hypervisor.