Nested VMX virtualization error on last Qemu versions

[Bondey]

Recently updated Qemu on a Sony VAIO sve14ag18m with Ubuntu Bionic 4.15.0-38 from Git

After launching a few VMs, noticed that i could not create Snapshot due to this error:
"Nested VMX virtualization does not support live migration yet"

I've created a new Windows 7 X64 machine with this compilation of Qemu and the problem persisted, so it's not because of the old machines.

I launch Qemu with this params (I use them for malware analisys adn re...):
qemu-system-x86_64 -monitor stdio -display none -m 4096 -smp cpus=4 -usbdevice tablet -drive file=VM.img,index=0,media=disk,format=qcow2,cache=unsafe -net nic,macaddr="...." -net bridge,br=br0 -cpu host,-hypervisor,kvm=off -vnc 127.0.0.1:0 -enable-kvm

Deleting the changes made on this commit solved the problem, but I dont have idea what is this for, so... xDD
https://github.com/qemu/qemu/commit/d98f26073bebddcd3da0ba1b86c3a34e840c0fb8

[Paolo Bonzini (bonzini)]

Hi,

the kernel you are using should not have nested virtualization enabled by default. Are you by chance using nested virtualization of some other virtual machines? If so, it's enough to add "-vmx" at the end of "-cpu host,-hypervisor,kvm=off".

If you are not sure of the answer, please check if your /etc/modprobe.conf file, or any file in your /etc/modprobe.d directory, contains the line "options kvm_intel nested=1".

Thanks!

[Thomas Huth (th-huth)]

The QEMU project is currently considering to move its bug tracking to another system. For this we need to know which bugs are still valid and which could be closed already. Thus we are setting older bugs to "Incomplete" now.
If you still think this bug report here is valid, then please switch the state back to "New" within the next 60 days, otherwise this report will be marked as "Expired". Or mark it as "Fix Released" if the problem has been solved with a newer version of QEMU already. Thank you and sorry for the inconvenience.

[Launchpad Janitor (janitor)]

[Expired for QEMU because there has been no activity for 60 days.]