RajanPatel

I recently got a Razer Blade (Razer Blade 17 _2022_ - RZ09-0423) which shipped with a 12th Gen Intel® Core™ i9-12900H × 20. Using <model fallback='allow'>Skylake-Client-noTSX-IBRS</model> was not going to work. I ran virsh capabilities and learned that I have a <model>Broadwell-noTSX-IBRS</model> Before I installed my Windows 11 VM under KVM in Ubuntu 22.04.3, I edited the CPU XML configuration, and removed host-passthrough and manually used just this. Note: "cores=8" because the number of vCPUs allocated to my Windows 11 machine was 8. You will want these numbers to match, or Virtual Machine Manager will complain. <cpu mode="custom" match="exact" check="partial"> <model fallback="allow">Broadwell-noTSX-IBRS</model> <topology sockets="1" dies="1" cores="8" threads="1"/> <feature policy="disable" name="hypervisor"/> <feature policy="require" name="vmx"/> <feature policy="disable" name="mpx"/> </cpu> This worked with great success. Windows 11 installed successfully, and I got an Ubuntu WSL 2 instances running inside my WIndows 11 VM. Attempting to change the CPU XML configurations in Virtual Machine Manager AFTER installing Windows 11 was a fool's errand. The performance hit may likely be remediated by appending the other CPU features as outlined in virsh capabilities. EDIT: I was able to simplify my CPU configuration to be just this: <cpu mode="custom" match="exact" check="partial"> <model fallback="allow">Broadwell-noTSX-IBRS</model> <feature policy="require" name="vmx"/> </cpu>