Re: [PATCH] libs/light: pass some infos to qemu

[Manuel Bouyer <bouyer@xxxxxxxxxxxxxxx>]

On Wed, Jan 27, 2021 at 10:06:43AM +0100, Roger Pau Monné wrote:
> On Tue, Jan 26, 2021 at 11:42:23PM +0100, Manuel Bouyer wrote:
> > On Mon, Jan 18, 2021 at 09:36:42AM +0100, Roger Pau Monné wrote:
> > > [...]
> > > 
> > > Note also that there are networking modes that don't use a bridge, so
> > > you could likely end up with nics[i].bridge == NULL?
> > 
> > I couldn't cause this to happen. If no bridge is specified in the
> > domU's config file, qemu-ifup is called with xenbr0 as bridge name.
> > 
> > I tried this:
> > vif = [ 'mac=00:16:3e:00:10:54, gatewaydev=wm0 type=ioemu, model=e1000' ]
> 
> Right, that's because libxl__device_nic_setdefault will set the bridge
> field to xenbr0 if empty.
> 
> I'm not opposed to this behavior, seeing as we don't have much other
> option I'm afraid. I guess we could open the tap interface in libxl
> and pass it to QEMU, so that libxl can call the hotplug script knowing
> the tap interface name, but that seems non-trivial.
> 
> IMO if we go that route it needs to be documented that NetBSD only
> supports bridged mode for emulated HVM network interfaces for the time
> being.

that's not quite true. As long as you have the domain ID in the qemu-if script,
you can query parameters from the store and do whatever you want here
(for example I use it to setup firewall rules). 

-- 
Manuel Bouyer <bouyer@xxxxxxxxxxxxxxx>
     NetBSD: 26 ans d'experience feront toujours la difference
--