Jeremy Fitzhardinge wrote: > >> The completely identical device model is of course ideal, but the >> implementation and consolidation of that is a long term prospect to >> move towards, not something that will happen immediately. We at least >> emulate physical hardware devices already, and will continue to need >> drivers compatible with those models for some time. > > Well, physical devices and completely emulated physical devices are > fairly straightforward - do it like real hardware. Its the semi-virtual > devices which pose problems. Either device emulations with a bit of > performance paravirtualization sprinkled over them, or virtualization > friendly devices which allow safe direct guest access, but need some > paravirtual management interfaces as well. > Those can still be detected by appearing in the PCI configuration space, though. It doesn't mean they actually have to emulate a PCI device. One of the "nice" things (from a virtualization perspective) is that there isn't a pan-architectural way to get to PCI config space, so on platforms where PCI is irrelevant, it can be implemented as a virtualization call. Multistandard devices obviously need to model real hardware more accurately, since that's the common denominator. -hpa _______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/virtualization
