[vfio-users] How To Verify Windows Uses Enlightenments ? Haswell And hv_vapic Parameter ?

[rob e]

I have recently changed a Windows VM from passthrough of an AMD gpu to 
nVidia gpu.
The VM runs win 8,1, the host is Ubuntu 16.04 (Xenial) with vanilla 
packages ie. libvirt 1.3.1, qemu 2.5

This has meant I needed to hide kvm and set the vendor_id. The vm now 
runs successfully with an nVidia card and nVidia drivers

I have 2 questions

1) How can I verify that windows still recognises the hyper-v facilities 
(hv_time,hv_relaxed,hv_vapic,hv_spinlocks=0x1fff) and is operating 
accordingly ?

2) I read that Haswell and newer include an apic facility which works 
faster without hv_vapic .... is this "rumour" accurate ? (I have a 
Haswell motherboard)
REF: 
https://www.reddit.com/r/VFIO/comments/479xnx/guests_with_nvidia_gpus_can_enable_hyperv/
If true should I disable hv_vapic ? Is it safe to assume that x2apic 
will remain enabled ?

thanks