Re: PCI passthrough support for PVH mode

[tosher 1 <akm2tosher@xxxxxxxxx>]

Hi Julien,

Thanks for the clarification!

Regrads,
Mehrab






On Thursday, February 10, 2022, 06:12:53 PM EST, Julien Grall <julien@xxxxxxx> 
wrote: 





Hi Bertrand,

On 10/02/2022 08:32, Bertrand Marquis wrote:
>> On 10 Feb 2022, at 07:22, tosher 1 <akm2tosher@xxxxxxxxx> wrote:
>>
>> Hi Jan,
>>
>> Thanks for letting me know this status.
>>
>> I am wondering if PCI passthrough is at least available in Arm for other 
>> virtualization modes like PV, HVM, or PVHVM. For example, is it possible for 
>> someone to attach a PCI device to a guest domain on an Arm machine and use 
>> that domain as a driver domain, like we can do with the Xen on x86?
> 
> On arm there is only one virtualization mode which is equivalent to x86 HVM.


I would like to correct this. Arm guests are more equivalent to x86 PVH 
than HVM. For more details, see:

https://wiki.xenproject.org/wiki/Understanding_the_Virtualization_Spectrum#PVH:

This is also why we need a brand new solution for PCI passthrough rather 
than piggying back on what was done on HVM in QEMU :).

Cheers,

-- 
Julien Grall