AMD Nested Virtualization Support

This is a wonderful news. However "Use a Windows guest with an OS version that is greater than or equal to the host OS version (19636) for now. " is not a correct statement in my opinion. I was able to successfully use Windows 10 1909 in the guest which is the version of Windows far below the 19636. From my own testing every 64 bit Windows operating system is working as a guest and it does not have to be newer than 19636.

proboszcz LpAdm is absolutely right.  We haven't validated the scenarios and performance on earlier versions of Windows.  In order to ensure a high performance, we have to have some enlightenments in the guest OSs.  This is also why we didn't bring up Linux support yet.  We're still working on some enlightenments there.  Once we have that, I'll make another post to share with the community at large.  Keep trying things out!

Chris

Please enable this also for older AMD Processors!

Michael-CM How old are we talking about here?  The biggest problem is there are some required CPU features to enable this support.  Depending on the age, this could prevent nested from working.

proboszcz You asked a few questions, let me see if I can address each one.

When will this feature be released: Our plan is to release it in future versions of Windows & Server but I'm not going to give a committed plan just yet as we need to get feedback and telemetry with the current implementation to see how much more work needs to be done.  Said another way, as of right now, yes, but, it's not a 100% yes.

Re: earlier versions - We're looking to backport this to Windows Server 2019 but don't have a committed date on that yet.

As for enlightenments, let me check with the team. I'll post an update here when I get an answer.  

Using the feedback hub is the best place for bugs as there are options for people to share logs there and it goes right into our bug tracking database.  For everything else, you can post here, uservoice, or feedback hub.  Note, I'll likely be checking here the most so take that into account.  

Deleted Some folks over on Github got the android emulator to work. Also the emulator team is aware of the feature reaching this level of maturity.  They haven't shared when their support gets into an Insider build but I can say they're excited as this is a highly desired feature for them.

Instead of getting personal let's stick to the facts.

1) AMD has had virtualization enabled CPU's for years.

2) AMD is (at least now) definitively better choice over Intel - performance or $ wise.

3) Microsoft has not implemented it in their own virtualization tech - Hyper V that they are pushing for quite strongly, driving out competition.

4) If we do not complain - nothing will change for sure.

5) Since we complain to Microsoft and Microsoft stays silent - that means we are in the right place - if it was AMD's fault, they would happily point the finger at AMD. 
6) Pain index to get this backported is too low - therefore we have to increase pressure on MS to do it, otherwise it will stay in low prio. 

or just switch to Linux KVM with GPU passthrough and install windows there for all the essential apps you cannot run from your distro. Which looks every day better as MS stays silent over this important, essential and otherwise basic feature. 

Personally, I do not believe MS could not have implemented it earlier. Hard to believe also that AMD bumped core counts up to 16 in consumer space without having Virtualization in mind completely. if there was solid evidence AMD virtualization tech was bad we would have heard about it already. Besides - it does work on Linux, yet does not on Windows - so what gives? 

I have seen the same issue as proboszcz when testing Windows 11 22000.100.210719-2150 about 2 months ago. I am not interested in synthetic benchmarks. I just measured a build in Visual Studio 2019 in the VM (level 1 guest). When nesting was not enabled for the VM, a clean build took 2 min, When nesting was enabled for the VM and Hyper-V installed, a clean build (same solution) took 3 minutes. This was reproducible.
My host hardware:
CPU AMD Ryzen Threadripper 2950X
Mainboard MSI MEG x399 Creation

I was really disappointed to see this slow down in the level 1 VM. If level 2 (nested) VMs would be a bit slower, it would be OK. I have not tried again with the release version of Windows 11, I am afraid the issue is still there.

Awesome news! Hyper-V is my favorite Hypervisor and the most powerful one.

chuybregts   How do I get this onto current windows 10 pro-2004?

I don't want to upgrade the entire base operating system to an insiders build.

It is an update to the underlying hyper-v hypervisor; There most be a way of merely patching the hypervisor without moving the entire OS to an insiders build?

Come on MS, we are hurting for this feature and want it delivered via a windows update. Not an insiders build update that will take 1-2 years to hit the mainstream.

Just want to patch the HV on my windows pro 2004, don't even need to update the GUI on HV management tools, because as far as I can tell, the expose CPU extensions is done via PowerShell on the VM itself. HV just needs to support SVM passthrough on the underlying hypervisor.

Why is this update an insider build patch????

is there anyway, official or unofficial, I can update my underlying hyper-v hypervisor, that's sit's underneath my windows 10 pro 2004 install, to get Nested under AMD to pass through, without moving the whole system to a windows insiders build??

I'm also desperate for information on when this feature will be available on the bi-annual or at least beta build.  I've been dual-booting to a dev build but like others cannot devote my rig solely to that, and switching between installs is cumbersome and just not viable.  

Yes - silly stupid me for not checking AMD compatibility before spending thousands on a Threadripper rig but this is painful!  Please please let us have some information soon!

Are Linux KVM guest(s) supported now?