I can't get vmx cpu extensions to show up in Virtualbox guests despite enabling nested paging and
enable vmx in virtualbox guest but this doesn't help that you check VT-X or the AMD Virtualization SVM it enables it for the guest to use BUT does not pass it through. This means if you check cat /proc/cpuinfo in the guest you will see the CPU doesn't support virtualization. It looks like VirtualBox still hasn't implemented this!
But there is good news I was able to install qemu-kvm and run straight from the VirtualBox .vdi directly and also enable the nested virtualization no problem.
#it looks like it is just not supported it's just easier to use KVM directly on the .vdi file!
qemu-system-x86_64 -enable-kvm -cpu host,vmx=on ~/VirtualBox\ VMs/test/test.vdi
Virtualbox is a great project and way for virtualizing but it is disappointing that they don't just pass through the virtualization CPU flags for nesting.
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