I have used KVM on earlier machines, other than the one I am on. I prefer KVM over Xen, but have both installed. I have major sound system bugs in openSUSE if I boot into Xen.
Any time I try to install an OS (have tried Kali and LinuxMint), the install will partially complete, then the VM will freeze. The virt-manager shows that it is paused, but it is actually locked up tight. I have to force kill it. Once that is done, it is impossible to resume. Even though the install didn't complete, the bootloader is looking for a drive to boot from and ignoring the original install ISO file.
I do have virtualization enabled in BIOS and can find no other settings that might cause problems.
Machine is an ASUS ROG Strix X570-F motherboard with a Ryzen9 3900X CPU. I run 64GB of DDR4-2666 RAM. I allow anywhere from 4GB to 12GB of RAM to the VM, and allow 4 cores. With Ryzen9, 4 cores equates to 8 logical processors (threads). I have also tried manually selecting the number of sockets-cores-threads from the VM setup.
The only thing I noticed is that the RAM seems to max out during the install, regardless of the RAM allowed. The failure always occurs sometime after it is using near 100% RAM.