On Wed, Jul 22, 2020 at 02:15:13AM +0200, Julia Suvorova wrote: > @@ -264,6 +265,10 @@ void __init pci_direct_init(int type) > { > if (type == 0) > return; > + > + if (raw_pci_ext_ops && kvm_para_available()) > + return; This is a bit of a subtle way of saying "If mmconfig exists, don't use the cf8 mechanism". There's probably a better way of doing this, but the x86 pci init sequence is already byzantine and I don't understand it well enough to offer you an alternative.