Nested: Error Hyper-V enlightened VMCS (hv-evmcs) requires Hyper-V virtual APIC (hv-vapic)

[carsten2]

I tried to enable hv-evmcs and "host" for the CPU, but the VM cannot be start of because of the error message "Hyper-V enlightened VMCS (hv-evmcs) requires Hyper-V virtual APIC (hv-vapic)". There is however not hv-apic option in the gui and this also cannot be set in the VM conf file.

apicv seems to be enabled in the system:

cat /sys/module/kvm_intel/parameters/enable_apicv
Result: Y

On page 33 of the presentation https://archive.fosdem.org/2019/sch...2860/vkuznets_fosdem2019_enlightening_kvm.pdf you can read, that there are two option hv_vapic and hv_evmcs:

"QEMU syntax: cpu ....,hv-vapic,hv-evmcs"

It seems that the problem is, that the option cannot be set in VM conf file in proxmox.

Any suggestions / solution?

 

[Unspec]

Assuming you're on intel, add +vmx to the VM's config.

/etc/pve/qemu-server/<VMID>.conf

cpu: host,flags=+[someflag];+[someflag];+vmx

Note that the GUI will look like no flags are being used since it doesn't know how to interpret flags outside of the available GUI ones. VMX, at least on my system, includes the vapic flag.

 

[HappyZombie_Slayer]

I'd like to take the time here and reply, just to let the world know that this indeed worked for me as well.

For reference, my system is using an Intel Xeon E3-2695 v4 CPU

Assuming you're on intel, add +vmx to the VM's config.

/etc/pve/qemu-server/<VMID>.conf

cpu: host,flags=+[someflag];+[someflag];+vmx

Note that the GUI will look like no flags are being used since it doesn't know how to interpret flags outside of the available GUI ones. VMX, at least on my system, includes the vapic flag.