Re: A set of "standard" virtual devices?

[Anthony Liguori <aliguori@us.ibm.com>]

Jeremy Fitzhardinge wrote:
> Andi Kleen wrote:
>> The implementation wouldn't need to use PCI at all. There wouldn't 
>> even need to be PCI like registers internally. Just a pci device
>> with an ID somewhere in sysfs. PCI with unique IDs
>> is just a convenient and well established key into the driver module
>> collection. Once you have the right driver it can do what it wants.
> 
> But I understood hpa's suggestion to mean that there would be a standard
> PCI interface for a hardware RNG, and a single linux driver for that
> device, which all hypervisors would be expected to implement.  But
> that's only reasonable if the virtualization environment has some notion
> of PCI to expose to the Linux guest.

The actual PCI bus could paravirtualized.  It's just a question of 
whether one reinvents a device discovery mechanism (like XenBus) or 
whether one piggy backs on existing mechanisms.

Furthermore, in the future, I strongly suspect that HVM will become much 
more important for Xen than PV and since that already has a PCI bus it's 
not really that big of a deal.

Regards,

Anthony Liguori

>     J