On Wed, Sep 14, 2011 at 8:35 AM, Avi Kivity <a...@redhat.com> wrote: > On 09/14/2011 11:27 AM, Alexander Graf wrote: >> >> On 14.09.2011, at 10:24, Jan Kiszka wrote: >> >> > On 2011-09-14 10:22, Avi Kivity wrote: >> >> On 09/14/2011 11:20 AM, Jan Kiszka wrote: >> >>>> >> >>>> Anyway PCI supports the vga region at 0xa0000-0xc0000. Where is it >> >>>> supposed to be mapped? >> >>> >> >>> ...but not all PCI bridges make use of this feature / forward legacy >> >>> requests. >> >>> >> >> >> >> Then this should be fixed in the bridge? >> > >> > Yes, it's a PPC bug. >> >> So how does the bridge not forward it then? >> > > I expect that currently vga adds the region to pci_address_space(). We need > to create a pci_address_space_vga() function that returns a region for vga > to use. Then add or remove the region to pci_address_space(), within the > bridge code, depending on whether the bridge forwards vga accesses or not.
Similar treatment should be also needed for VGA IO ports 0x3b0 etc. > (assuming I understood the problem correctly - not sure) I think you did.