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I assume this case can be > an exception since there's no point in allowing a device that has no > driver yet to access any reserved region? If require_direct is set then we have to disable this mechanism.. I'm not sure exactly what to do about this as the require_direct comes from the hypervisor in a CC VM and we probably don't want to give the hypervisor this kind of escape hatch. Perhaps we need to lock off to failure on CC VMs if this ever happens.. But baremetal should just keep working how it always worked in this case.. Jason