Re: Using VMChannel to communicate with the host.

Troy Benjegerdes
2007-09-08T00:51:23Z

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.