[libvirt] [PATCH] Update domain xml after usb hotplug

[Richard W.M. Jones]

On Thu, Aug 21, 2008 at 11:21:33PM -0400, Cole Robinson wrote:
> The recently added usb hostdev and mass storage device
> hotplug code doesn't append the devices to the running
> guests xml if the hotplug succeeds. The attached patch
> fixes this.

IIRC there was some question about whether it should actually do this.
I think it should -- a user would expect that when you attach a device
to a domain, the device should appear in the XML (and be persistent
too).

So I ACK this patch.

This code pattern:

> +    /* Find spot in domain definition where we will put the disk */
> +    ptr = vm->def->disks;
> +    prev = &(vm->def->disks);
> +    while (ptr) {
> ....

appears at least twice.  What we need is a Set abstract type.
Implementing it as a red-black self-balancing tree would avoid any
unexpected surprises when someone's guest has 100s of devices
attached.

Rich.

Ob-OCaml-hack.  The Set type in OCaml, implemented as an RB-tree,
comes with a formal proof of correctness which runs to 5000 lines and
took two man-months to complete.  Along the way they found bugs in the
original implementation.

-- 
Richard Jones, Emerging Technologies, Red Hat  http://et.redhat.com/~rjones
virt-p2v converts physical machines to virtual machines.  Boot with a
live CD or over the network (PXE) and turn machines into Xen guests.
http://et.redhat.com/~rjones/virt-p2v