I want to use the WSL2 in my Linux. Yes, it’s weird but there are some use cases though I hate WSL2 and Hyper-V! The Hyper-V support in VirtualBox is not good and I failed to use the WSL2 when using VirtualBox. The VMware Fusion Player should have well support for Hyper-V (they work together with Microsoft to add this feature) but their license doesn’t allow commercial use.

So I tried the Virt-Manager and I like it now. It has a UI and a corresponding XML (so I am doing the declarative programming!) to configure the VM and can easily add new hardware/modules to VMs. The bad part is you need to check the documentation and related resources to configure some features that could be easier done in other VM software e.g. adding a shared folder. Like using other open-source software, I can bear with it and I can totally understand the main focus when developing these programs.

This is a simple guide that mainly lists some tips I found when installing/using Windows 11 + WSL2 in Virt-Manager/QEMU.

The below articles in ArchWiki are a good start:
https://wiki.archlinux.org/title/Virt-Manager
https://wiki.archlinux.org/title/libvirt
https://wiki.archlinux.org/title/QEMU

qemu:///system vs qemu:///session

I don’t list any differences between them as there are already some online resources1 about it.

I tried to use the qemu:///session, but I found it can’t work with virtiofs Filesystem currently and I use the qemu:///system now.

Install Windows 11

Windows 11 requires the TPM and secure boot. You could install a TPM related package and run a command to emulate, but I prefer not to use the TPM and secure boot which is not useful for a VM environment.

Run reg add HKLM\SYSTEM\Setup\LabConfig /v BypassTPMCheck /t REG_DWORD /d 1 and reg add HKLM\SYSTEM\Setup\LabConfig /v BypassSecureBootCheck /t REG_DWORD /d 1 via a guide like this helps to bypass these Windows 11 installation requirement checks.

Using the no@thankyou.com tip here can bypass using a Microsoft account.

Copy & Paste

Installing “Windows SPICE Guest Tools” can provide this feature: https://www.spice-space.org/download.html

Shared Folders

You could use the “Add Hardware” option in Virt-Manager to add the “Filesytem” with “virtiofs” driver to map folders from host (Linux) to guest (Windows).

Then refer to the guide here to virtiofs drivers to see the shared folders: https://virtio-fs.gitlab.io/howto-windows.html

I soon found I can’t save the VM snapshot now, and it would throw below exception because it seems the virtiofs doesn’t support live migration:

Error saving domain: Requested operation is not valid: cannot migrate domain: non-migratable device: 0000:00:02.4:00.0/vhost-user-fs

Traceback (most recent call last):
  File "/usr/share/virt-manager/virtManager/asyncjob.py", line 72, in cb_wrapper
    callback(asyncjob, *args, **kwargs)
  File "/usr/share/virt-manager/virtManager/vmmenu.py", line 162, in cb
    vm.save(meter=asyncjob.get_meter())
  File "/usr/share/virt-manager/virtManager/object/libvirtobject.py", line 57, in newfn
    ret = fn(self, *args, **kwargs)
  File "/usr/share/virt-manager/virtManager/object/domain.py", line 1450, in save
    self._backend.managedSave(0)
  File "/usr/lib/python3.10/site-packages/libvirt.py", line 1810, in managedSave
    raise libvirtError('virDomainManagedSave() failed')
libvirt.libvirtError: Requested operation is not valid: cannot migrate domain: non-migratable device: 0000:00:02.4:00.0/vhost-user-fs

So I use Samba instead and use Windows to connect the Samba server for sharing files.

I found this gist tutorial is an easy start to add the Samba service in my local Linux. Because I use Firewalld, I ran sudo firewall-cmd --permanent --zone=libvirt --add-service=samba to expose my Samba service for Windows VM.

Using WSL2 in Windows 11

The WSL2 needs the “Virtual Machine Platform” windows feature. My CPU is 13600k and I have a hard time finding the needed puzzle to make the WSL2 work in it.

Use the docs here to enable the nested virtualization in KVM and adding the below in my Virt’s VM XML helps otherwise my Windows would be stuck in the “Preparing Automatic Repair” loop after installing the WSL and restarting Windows 11.

<cpu mode="custom" match="exact" check="partial">
<model fallback="allow">Skylake-Client-noTSX-IBRS</model>
<feature policy="disable" name="mpx"/>  
<feature policy="require" name="vmx"/>
</cpu>

If you use a different CPU series, you may need to find another Qemu CPU configuration to make it works in your case and I hope you could find one.

Also, big thanks to the info below which helps me:
https://www.reddit.com/r/VFIO/comments/usc7dd/intel_12th_gen_cpus_not_working_with_hyperv/
https://www.redpill-linpro.com/techblog/2021/04/07/nested-virtualization-hyper-v-in-qemu-kvm.html