To: Wang, Wei W <address@hidden>
Cc: address@hidden; address@hidden; virtio-
address@hidden; address@hidden; address@hidden
Subject: Re: [virtio-comment] [PATCH] *** Vhost-pci RFC v2 ***
On Mon, Jun 27, 2016 at 02:01:24AM +0000, Wang, Wei W wrote:
On Sun 6/19/2016 10:14 PM, Wei Wang wrote:
This RFC proposes a design of vhost-pci, which is a new virtio device type.
The vhost-pci device is used for inter-VM communication.
Changes in v2:
1. changed the vhost-pci driver to use a controlq to send acknowledgement
messages to the vhost-pci server rather than writing to the device
configuration space;
2. re-organized all the data structures and the description
layout;
3. removed the VHOST_PCI_CONTROLQ_UPDATE_DONE socket message,
which
is redundant;
4. added a message sequence number to the msg info structure to
identify socket
messages, and the socket message exchange does not need to be
blocking;
5. changed to used uuid to identify each VM rather than using the
QEMU
process
id
One more point should be added is that the server needs to send
periodic socket messages to check if the driver VM is still alive. I
will add this message support in next version. (*v2-AR1*)
Either the driver VM could go down or the device VM (server) could go
down. In both cases there must be a way to handle the situation.
If the server VM goes down it should be possible for the driver VM to
resume either via hotplug of a new device or through messages
reinitializing the dead device when the server VM restarts.