Re: [Qemu-devel] [v5][PATCH 0/5] xen: add Intel IGD passthrough support

[Paolo Bonzini]

Il 26/06/2014 13:36, Michael S. Tsirkin ha scritto:
> > It should be this way in real hardware too
> But it isn't.

That's why I mentioned that this hack should become architecturally 
specified (since it can work on real hardware too) with QEMU doing the 
emulation for current-generation devices.

> > (not exactly _this_ hack, but at least no improper relationship among
> > IGD/MCH/PCH).
>
> Well that dependency between devices is common for embedded hardware,
> and this is what we have here.

Sure, but then you should put MCH/PCH/IGD in the same IOMMU group, which 
basically means forgetting about IGD assignment.

Paolo