Hello everyone, Long time Parallels user here. I updated to macOS Big Sur 11.0.1 as most did, a few days ago, and I am already running on Parallels 16.1.1. One of my VMs has an atypical setup: it has no virtualized drive, and it boots from an external SSD instead, on which I installed Windows 10, because I also used it as a Bootcamp boot device. So, basically, Under "Boot Order", I have "External device" first. Under "Advanced Settings", I have "vm.bios.efi=1". Under Catalina, this worked perfectly. Under Big Sur, the VM starts, and it gets stuck with 100% CPU usage on the EFI screen; Windows doesn't even get loaded. On VMs running from a virtualized drive, I have no issues at all. Does anyone know of a workaround?
I managed to solve it. If anyone wonders, Parallels 16 now offers an option to choose a PHYSICAL drive as the VM hard drive, without the need to set it up as an external device on boot. I re-created a VM using this method, and it works.