Re: [Qemu-devel] [PATCH 2/5] xen, gfx passthrough: reserve 00:02.0 for INTEL IGD

[Anthony PERARD <anthony.perard@citrix.com>]

On Fri, Feb 21, 2014 at 02:44:10PM +0800, Yang Zhang wrote:
> From: Yang Zhang <yang.z.zhang@Intel.com>
> 
> Some VBIOSs and drivers assume the IGD BDF (bus:device:function) is
> always 00:02.0, so this patch reserves 00:02.0 for assigned IGD in
> guest.
> 
> The original patch is from Weidong Han <weidong.han@intel.com>
> 
> Signed-off-by: Yang Zhang <yang.z.zhang@Intel.com>
> Cc: Weidong Han <weidong.han@intel.com>
> ---
>  hw/pci/pci.c |    6 ++++++
>  1 files changed, 6 insertions(+), 0 deletions(-)
> 
> diff --git a/hw/pci/pci.c b/hw/pci/pci.c
> index 4e0701d..e81816e 100644
> --- a/hw/pci/pci.c
> +++ b/hw/pci/pci.c
> @@ -808,6 +808,12 @@ static PCIDevice *do_pci_register_device(PCIDevice *pci_dev, PCIBus *bus,
>      if (devfn < 0) {
>          for(devfn = bus->devfn_min ; devfn < ARRAY_SIZE(bus->devices);
>              devfn += PCI_FUNC_MAX) {
> +#if defined(CONFIG_XEN_PCI_PASSTHROUGH)
> +            /* If gfx_passthru is in use, reserve 00:02.* for the IGD */
> +            if (gfx_passthru && devfn == 0x10) {
> +                continue;
> +            }
> +#endif
>              if (!bus->devices[devfn])
>                  goto found;
>          }

This does not look quite right, there is maybe another way to reserve a
devfn.

-- 
Anthony PERARD