Re: kvm PCI assignment & VFIO ramblings

Roedel, Joerg
2011-08-22T12:36:51Z

On Mon, Aug 22, 2011 at 06:51:35AM -0400, Avi Kivity wrote:
> On 08/22/2011 01:46 PM, Joerg Roedel wrote:
> > That does not work. The bridge in question may not even be visible as a
> > PCI device, so you can't link to it. This is the case on a few PCIe
> > cards which only have a PCIx chip and a PCIe-2-PCIx bridge to implement
> > the PCIe interface (yes, I have seen those cards).
>
> How does the kernel detect that devices behind the invisible bridge must
> be assigned as a unit?

On the AMD IOMMU side this information is stored in the IVRS ACPI table.
Not sure about the VT-d side, though.

Joerg

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