Hey, thats exactly the same issue I have running Windows 2022 with HyperV feature enabled. This simply does not work on AMD, it freezes soon or later. However I was able to run HyperV on Core Installation (without Desktop Experience) which is unfortunatelly no sollution for your Windows 11. Did you have allready tried to disable Windows Defender and process Isolation features?
I don't think the issue is in the guest OS level. It doesn't BSOD so there is no kernel level fault occurring, the system also does not respond to interrupts like ctrl-alt-del and the proxmox console only shows a black screen and does not respond to power state commands. I assume it is an issue with nested virtualization in the guest VM hardware level.
I'm going to remove the Hyper-V feature and see if the issue continues (Not really a workaround since KVM64 seems stable and is the same end state with no nested virtualization to run features like wsl2.)
The black screen is becouse of your power management setting. If you disable to switch off the display you will see, that the os freezes and does not react to any input. There seems to be some constrain in the UI version running HyperV nested in Proxmox on AMD CPU..
The Server 2022 Core installation works smooth and even really quick without any issue.
See my post here:
https://forum.proxmox.com/threads/windows-server-2022-with-hyperv-is-freezing.103917/
The Server 2022 Core installation works smooth and even really quick without any issue.
See my post here:
https://forum.proxmox.com/threads/windows-server-2022-with-hyperv-is-freezing.103917/
Windows 11 uses enhanced Hardware Security. One of them is the "Core Isolation" which is virtualisation-based security. So it must not be the HyperV only causing this issue on AMD CPU, but maybe this too.
Changing the CPU Arch to KVM removs the virtualisation capability of the CPU from the guest. So if you do not need any nested virtualisation and you don't like to deal to find out what's causing this, is this the best sollution in my opinion.
Changing the CPU Arch to KVM removs the virtualisation capability of the CPU from the guest. So if you do not need any nested virtualisation and you don't like to deal to find out what's causing this, is this the best sollution in my opinion.
I've been updating my AMD machine whenever a new kernel comes along and Windows 11 with virtualization enabled is no longer hanging. Has this been fixed?
I've not been paying enough attention with all the new kernels being launched in the past months but something recently launched must has fixed the AMD issues! I've been updating Win11 as well, so not sure what fixed it.
I've not been paying enough attention with all the new kernels being launched in the past months but something recently launched must has fixed the AMD issues! I've been updating Win11 as well, so not sure what fixed it.
I have this issue with updated Win11, but I'm still on 7.1-12. Upgrading now to see if that fixes it. If you don't hear from me again, it probably worked.
Setting the CPU to KVM64 made a massive improvement for me. Cheers mijanek 
100% CPU in the guest to 20% - It was completely unusable before. Strangely this issue seems to be inconsistent when I use the "host" CPU type - After restarting the host, this issue sometimes is that and other times it isn't. I am using the dev version of Proxmox so this may explain the differences - I don't have time to test further as I need to use this guest. Anyway, thanks for you help.
100% CPU in the guest to 20% - It was completely unusable before. Strangely this issue seems to be inconsistent when I use the "host" CPU type - After restarting the host, this issue sometimes is that and other times it isn't. I am using the dev version of Proxmox so this may explain the differences - I don't have time to test further as I need to use this guest. Anyway, thanks for you help.
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you shouldn't use "Host" as cpu type in production. Host type pass all cpu flags inside the vms, as if a feature is not well supported by qemu, it can give bug. That's why they are specific cpu models for each cpu generation. Theses models are tested, and unsupported cpuflags are filtered by qemu.Setting the CPU to KVM64 made a massive improvement for me. Cheers mijanek
100% CPU in the guest to 20% - It was completely unusable before. Strangely this issue seems to be inconsistent when I use the "host" CPU type - After restarting the host, this issue sometimes is that and other times it isn't. I am using the dev version of Proxmox so this may explain the differences - I don't have time to test further as I need to use this guest. Anyway, thanks for you help.
Interestingly reading here seems to suggest otherwise: https://forum.proxmox.com/threads/cpu-type-host-vs-kvm64.111165/ and I have not had any issues with any of the Linux VM's I have running. In fact I have seen CPU utilisation decrease on the host.
I would agree that running VM's with "host" as the CPU type under production would not be ideal. In my particular use case which is to reduce CPU utilisation to the lowest possible amount (due to high energy costs in the UK) seems be be fine - well apart from the one Windows 11 VM that runs at 100% CPU when it literally doing nothing