Do you have experience with VirtualBox in Debian 13 trixie?

[daniel.m.tripp (Dan Tripp)]

Isn’t there already another thread you started about clashing between VirtualBox and KVM? Why not just update the original thread / subject you started instead of starting a new one?

Wasn’t it solved? I’m sure there was an answer to your issue from @kovacslt :

VirtualBox 7.1.14: VirtualBox can't operate in VMX root mode. Please disable the KVM kernel extension

This was also linked in the VirtualBox 7.2.2 change log as one of the issues fixed. I thought I would add it here. Seems to be an on again off again problem dealing with kernel versions and VirtualBox versions. I found the information in this issue thread helpful and informative. VirtualBox Issues with KVM

@kovacslt

Moving from Debian 12 to 13 I faced the same problem.
My readings told me it’s because the newer kernel loads and inits kvm module by default, whereas the previous version did not. This makes impossible for Virtualbox to init virtualization on its own, so the sulotion is either to disable kvm initialization in GRUB adding a kernel parameter ( kvm.enable_virt_at_load=0 ) , or blacklist kvm module via /etc/modprobe.d/something.conf.
I choosed the latter, this what how it looks now on my computers:

cat /etc/modprobe.d/kvm-blacklist.conf 
blacklist kvm_intel

Adding that, and rebooting made Virtualbox working flawlessly.
As for version, I have now Virtualbox 7.2, is there a reason you are still trying 7.1?

The answer to your question on Ubuntu 24.04x should be exactly the same for Debian 13…