Problems since new Kernels

[Gamerios]

Hello,

Ubuntut 20.04 and QEMU Virt-Manager - Nested virtualization suddenly doesnt work

Since Yesterday when i want start Windows 10 VM in Ubuntu 20.04 and QEMU 4.2.1 also tryed 5.2 and 6.2 and latest

i get this error:

Code:

qemu-system-x86_64: error: failed to set MSR 0x48f to 0xffffff00036dfb qemu-system-x86_64: /home/user/qemu-4.2.1/target/i386/kvm.c:2691: kvm_buf_set_msrs: Assertion `ret == cpu->kvm_msr_buf->nmsrs' failed.

i have kvm ignore_msrs=1 and so on tryed ON and OFF like before it worked in XML

Code:

Anyone can help it worked now for years but now not anymore since apt update and apt upgrade need downgrade Ubuntu Linux Kernel?

i need CPU Host-Passthrough otherwise Windows 10 has no good performance like in all Windows 10 Gaming VM GPU Passthrough Tutorials stand and also i tested

Hope any one can help here also GRUB

Code:

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash intel_iommu=on kvm.ignore_msrs=1 video=efifb:off vfio-pci.ids=10de:2486,10de:228b,10de:2503,10de:228e isolcpus=3-13,17-27 nohz_full=3-13,17-27 rcu_nocbs=3-13,17-27 msr.allow_writes=on kvm.intel_nested=1"

A and Ubuntu Linux Kernel 5.11.0-43-generic

and when start MacOS VM also with CPU Host-Passthrough it work witout an Error hmm

Thank ya Kind Regards

[bryansteiner]

Sorry for the long delay with no response. This just isn't an issue I'm familiar with. Have you attempted the following solution? https://github.com/GNS3/gns3-server/issues/1774#issuecomment-639396742

[bryansteiner]

Closing since no response and the issue was already raised here (GNS3/gns3-server) where it is more likely to be answered