Description of problem: Deactivating a VM's sole bootable disk while the VM is running is valid, while activating VMs with no bootable disks is not supported. This causes an inconsistent behavior in the system. How reproducible: 100% Steps to Reproduce: 1. Add a VM. 2. Add a bootable disk. 3. Run the VM. 4. Deactivate the disk. Actual results: Deactivation succeeds. Expected results: Deactivation should fail, as this is the sole bootable device.
Once a VM is up it no longer really needs a bootable device. I'd much rather keep consistency between cold (un)plugging and hot un(plugging) than running a VM and editing its state while it's up. closing.