Re: [Xen-devel] [PATCH 3/3] x86/xen: use guest_late_init to detect Xen PVH guest

From: Juergen Gross
Date: Wed Nov 08 2017 - 07:40:51 EST


On 08/11/17 13:26, Paolo Bonzini wrote:
> On 08/11/2017 13:24, Juergen Gross wrote:
>>> My understanding of Xen is very rusty at this point, but I think a
>>> "completely" legacy-free HVM domain will still have a PCI bus and the
>>> Xen platform device on that bus.
>>>
>>> A PVH domain just knows how to access the Xen PV features.
>>
>> A HVM domain does so, too. Today maybe only partially, but e.g. event
>> channels work in a HVM domain even without the Xen platform device.
>> Grant tables can be made working without the platform device, too,
>> and I'm already preparing a patch to do exactly that.
>
> What about assigned PCI devices? I think they are not PV pcifront for
> HVM. So the main difference in the end is the PCI bus.

Sure, but this is easily detectable, isn't it?


Juergen