VT-X nested virtualisation 6.12

[Nano]

Hi, I followed spaceinvaders Ilkley old guide and the user scripts enabling and disabling nested virtualisation definitively work but weirdly my window VM just go to a recovery screen when it’s on until I disable it again via the NV disable script.

 

do I have to do a fresh install with VT-x on (fyi I have an Intel CPU)

Very strange stuff.

 

anyone got VT_X working nicely with window that can share an xml. I assume host pass through is also needed?

 

[Kilrah]

Nested virtualization is basically not possible with Windows at this point, AFAIK it requires upcoming fixes to the Linux kernel. 

[SimonF]

2 hours ago, Nano said:

Hi, I followed spaceinvaders Ilkley old guide and the user scripts enabling and disabling nested virtualisation definitively work but weirdly my window VM just go to a recovery screen when it’s on until I disable it again via the NV disable script.

 

do I have to do a fresh install with VT-x on (fyi I have an Intel CPU)

Very strange stuff.

 

anyone got VT_X working nicely with window that can share an xml. I assume host pass through is also needed?

 

Are you looking to run WSL or HyberV?

[Nano]

1 hour ago, SimonF said:

Are you looking to run WSL or HyberV?

Hyper-V, Or virtual box within the OS for example.

[SimonF]

18 hours ago, Nano said:

Hyper-V, Or virtual box within the OS for example.

I set this option in my syslinix kvm-intel.nested=1 and can run an unraid test server with a VM on it.

 

Try removing HyperV settings.

 

I know this is for AMD but maybe some hints.

 

 

[Nano]

 

On 5/14/2023 at 11:41 AM, SimonF said:

I set this option in my syslinix kvm-intel.nested=1 and can run an unraid test server with a VM on it.

 

Try removing HyperV settings.

 

I know this is for AMD but maybe some hints.

 

 

So even with a fresh install, windows goes to a recovery screen when on. 
 

13th Gen I5 for reference

[Nano]

 

On 5/14/2023 at 11:41 AM, SimonF said:

I set this option in my syslinix kvm-intel.nested=1 and can run an unraid test server with a VM on it.

 

Try removing HyperV settings.

 

I know this is for AMD but maybe some hints.

 

 

So even with a fresh install, windows goes to a recovery screen when on. 
 

13th Gen I5 for reference

[Kilrah]

Yeah, just not possible on Intel at this point, seems AMD is fine.

 

Edited May 17, 2023 by Kilrah

[Nano]

26 minutes ago, Kilrah said:

Yeah, just not possible on Intel at this point, seems AMD is fine.

 

Thanks it’s really hard to find info on this. I assume if the host was windows server for example it would work?

[Kilrah]

Probably, but then Hyper-V VMs are pretty unfriendly for local access...

[Nano]

I found this works if you go Linux Linux windows - Unraid > Ubuntu > virtual box > windows although slow does work but it took like 20 minutes to even boot to the windows login page so it’s not really usable 

Edited May 20, 2023 by Nano

[gregor160300]

For Intel I found this proxmox discussion: I tried it with proxmox as a VM on unraid and windows as a VM inside that and WSL inside that Windows VM. It worked (although very slow). However proxmox uses qemu instead of libvirt. So I think we just need to figure out how to correctly get these changes to work with libvirt:

args: -cpu Cooperlake,hv_relaxed,hv_spinlocks=0x1fff,hv_vapic,hv_time,+vmx
cpu: host

[mackid1993]

OK so you can change your CPU to this emulated one and everything will work but there is a performance hit from it:

Here is the XML. You just have to edit the topology for your cores. I did this on 12700k so I gave it 20 cores. I no longer run this due to the performance issues.

  <cpu mode='custom' match='exact' check='partial'>
    <model fallback='allow'>Skylake-Client-noTSX-IBRS</model>
    <topology sockets='1' dies='1' cores='20' threads='1'/>
    <feature policy='disable' name='hypervisor'/>
    <feature policy='require' name='vmx'/>
    <feature policy='disable' name='mpx'/>
  </cpu>

 

Edited September 21, 2023 by mackid1993

[sillstrybarn]

So this is not fixed in latest unraid version?

[ArchonX]

On 2023/12/27 at PM4点14分, sillstrybarn said:

那么最新的 unraid 版本中没有修复这个问题吗？

截止到24年1月31日，该问题仍没有被解决，13900K仍然无法在windows上运行嵌套虚拟化

 

[nyavana]

Can confirm it is still not working, Hyper-v only works with CPU passthrough even the Hyper-V option is enabled in vm setting.

[feraay]

I try to run docker with wsl2 on windows server 2022 vm. 

when I modify the  cpu part the vm does boot

with cpu passtrough it only boots into recovery.

 

But even with modified xml docker doesn’t work.

 

so it’s a Linux kernel thing? 
 

 Intel 13900 no gpu passtrugh 

[feraay]

Adding the following to XML seems to work. 

Cpu is set to host-passthrough

<qemu:commandline>
  <qemu:arg value='-cpu'/>
  <qemu:arg value='host,level=30,-waitpkg'/>
</qemu:commandline>

 

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