Re: A set of "standard" virtual devices?

["H. Peter Anvin" <hpa@zytor.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.
> 

That is, of course, true, although "some notion of" is very broad, and 
one could also use this for detection and some hypervisor-specific 
communication for the actual I/O.

However, one probably wants to think about what the heck one actually 
means with "virtualization" in the absence of a lot of this stuff.  PCI 
is probably the closest thing we have to a lowest common denominator for 
device detection.

	-hpa