Ian Campbell wrote:
>
>
> I think gfx_passthrough is actually a boolean, right? In that case it
> should be declared as "bool" in the idl.
>   

Well, the integer value of gfx_passthru had meaning in 2009, I suspect. 
It differentiated between IGD adapter and discrete adapter.
http://xen.1045712.n5.nabble.com/PATCH-0-2-v2-graphics-passthrough-with-VT-d-td2534811.html

At now, I didn't notice integer meaning of this variable in the code. I 
changed it to bool in the new patch.

Sergey.