Re: Using VMChannel to communicate with the host.

Dor Laor
2007-09-09T08:38:42Z

Troy Benjegerdes wrote:
> On Fri, Sep 07, 2007 at 04:44:30PM -0600, Cam Macdonell wrote:
>
>> Hi,
>>
>> I'm trying to get a better understanding of VM-to-host communication
>> that doesn't involve going over virtual networks. I understand there
>> are a couple of developments underway, but I just want to play around a
>> better sense of things. I think the current hypercall mechanism is the
>> current way to do this using the -vmchannel option. But, I'm not very
>> experienced with PCI devices and their drivers so I need some help. All
>> I want to do is to communicate across a unix domain socket on the host.
>> Besides loading the hypercall module in the guest how do things needs
>> to be configured on the host?
>>
>> Is there a simple tutorial or just a webpage with examples for how to do
>> this?
>>
>
> I'm going to suggest that a better way to do VM-to-host or VM-to-VM
> communication would be to write an OpenFabrics (www.openfabrics.org)
> driver that uses hypercalls. There is probably some gotcha I am not
> aware of, but I think this would allow direct userspace to userspace
> communication between a process running on a host, and a process running
> on a VM, while still maintaining isolation.
>
>
Basically that's true but you need a host glue dirver to connect the two
+ the hypercall implementation.
It can be easily added to KVM with a small cost.

BTW: does all windows guest will have the guest side driver implemented?
Including XP, 2k, Vista?