Re: [PATCH] AF_VMCHANNEL address family for guest<->host communication.

David Miller
2008-12-15T22:29:18Z

From: Anthony Liguori <anthony@codemonkey.ws>
Date: Mon, 15 Dec 2008 14:44:26 -0600

> We want this communication mechanism to be simple and reliable as we
> want to implement the backends drivers in the host userspace with
> minimum mess.

One implication of your statement here is that TCP is unreliable.
That's absolutely not true.

> Within the guest, we need the interface to be always available and
> we need an addressing scheme that is hypervisor specific. Yes, we
> can build this all on top of TCP/IP. We could even build it on top
> of a serial port. Both have their down-sides wrt reliability and
> complexity.

I don't know of any zero-copy through the hypervisor mechanisms for
serial ports, but I know we do that with the various virtualization
network devices.

> Do you have another recommendation?

I don't have to make alternative recommendations until you can
show that what we have can't solve the problem acceptably, and
TCP emphatically can.