Enabling KVM

[gameveloster]

Hi, I have a Ubuntu 24.04 VM running on Proxmox 8.2.2 where I am trying to get `/dev/kvm`. Proxmox is running on a machine with a AMD Ryzen 7 2700X Eight-Core Processor.

On the Proxmox host, nested virtualization is enabled

# cat /sys/module/kvm_amd/parameters/nested
1

and KVM is enabled

# kvm-ok
INFO: /dev/kvm exists
KVM acceleration can be used

However KVM is not enabled inside the VM. Tried with both kvm64 and host as the VM CPU.

kvm-ok fails when run inside the VM:

$ sudo kvm-ok
INFO: Your CPU does not support KVM extensions
KVM acceleration can NOT be used

How can I get KVM support inside the VM? Thanks

 

[alexskysilk]

enable virtualization in your bios.

consult your motherboard's user guide if you need more information.

 

[leesteken]

Please show your VM configuration (file). What virtual CPU are you using? Have you tried 'host' instead?

 

[gameveloster]

enable virtualization in your bios.

consult your motherboard's user guide if you need more information.

Checked my Proxmox machine's motherboard BIOS and virtualization (SVM) has always been enabled.

Please show your VM configuration (file). What virtual CPU are you using? Have you tried 'host' instead?

Yes, I have tried both the virtual CPU 'kvm64' and the 'host' CPU, which is AMD Ryzen 2700X.

Does this screencap show the VM config that you need?

 

[leesteken]

Checked my Proxmox machine's motherboard BIOS and virtualization (SVM) has always been enabled.

Otherwise the VM would not run. This is not the problem.

Yes, I have tried both the virtual CPU 'kvm64' and the 'host' CPU, which is AMD Ryzen 2700X.

That's weird. I don't know about kvm64 (but I doubt it will expose svm) but host should have worked.

Does this screencap show the VM config that you need?
View attachment 69600

I would prefer to see the actual configuration file (from the /etc/pve/qemu-server/ directory, in text between CODE-tag) instead of a screenshot of only part of it. I can't tell if you tried host instead of kvm64 with stopping and restarting the VM.
According to the Wiki, a good test is egrep '(vmx|svm)' --color=always /proc/cpuinfo (inside the VM) when running the VM with CPU Type host.

 

[gameveloster]

I can't tell if you tried host instead of kvm64 with stopping and restarting the VM.

Restarting after changing CPU to 'host' did the trick! Thanks!

$ sudo kvm-ok
INFO: /dev/kvm exists
KVM acceleration can be used