On Mon, Sep 02, 2013 at 05:05:10PM +0100, Peter Maydell wrote: > On 2 September 2013 17:00, Michael S. Tsirkin <m...@redhat.com> wrote: > > On Mon, Sep 02, 2013 at 04:53:50PM +0100, Peter Maydell wrote: > >> at the moment what happens is that the pci controller > >> creates the PCI memory and io memory regions (or cheats > >> by reusing the system memory space[*]), > > >> [*] I'm pretty sure this is a bug in all platforms that do it. > > > Well as usual this cheat originated with PIIX. > > AFAIK PIIX actually has a shared bus for memory and PCI > > so this is not a bug there, I think. > > It will be when you introduce this "return -1 for unassigned > addresses", though, since you only want that to happen > for PCI accesses, not system memory accesses, right? > > thanks > -- PMM
What happens with PIIX is that everything that is not in system memory is PCI. So there's no such thing as "unassigned system memory address": all unassigned addresses are PCI addresses. -- MST
