Re: [new PV device]

["Roger Pau Monné" <roger.pau@citrix.com>]

On 14/04/14 17:45, Vincenzo Maffione wrote:
> Hi,
>    I would like to design a new paravirtual device for Xen PV guests
> (under Linux),
> for research purposes.
> This device should be a "simplification" of netfront/netback in that
> the interface
> with the domU/dom0 O.S. is not the normal TCP/IP stack, but something way
> simpler (however, this is not so important w.r.t. my question).
> 
> Looking at the netback code
>      linux:drivers/net/xen-netback/xenbus.c
> I've run into some "hotplug scripts" support code.
> The netfront code, on the other hand, has no hotplug-related code.
> 
> I don't really understand what is the purpose of this hotplug support
> (Is it something
> related to the vif-* scripts?), but I'm wondering whether I can get
> rid of this code for my
> "simplified" device.

This hooks were used by xend, which relies on udev for launching hotplug
scripts. libxl launches scripts directly, so if you are adding a new
device, and don't need xend compatibility, you can get rid of them AFAIK.

Roger.