Re: [PATCH v2] libs/light: pass some infos to qemu

[Roger Pau Monné <roger.pau@xxxxxxxxxx>]

On Fri, Jan 29, 2021 at 11:46:53AM +0100, Manuel Bouyer wrote:
> On Thu, Jan 28, 2021 at 12:08:02PM +0100, Roger Pau Monné wrote:
> > On Tue, Jan 26, 2021 at 11:47:58PM +0100, Manuel Bouyer wrote:
> > > Pass bridge name to qemu as command line option
> > > When starting qemu, set an environnement variable XEN_DOMAIN_ID,
> > > to be used by qemu helper scripts
> > > The only functional difference of using the br parameter is that the
> > > bridge name gets passed to the QEMU script.
> > > NetBSD doesn't have the ioctl to rename network interfaces implemented, 
> > > and
> > > thus cannot rename the interface from tapX to vifX.Y-emu. Only qemu knowns
> > > the tap interface name, so we need to use the qemu script from qemu 
> > > itself.
> > > 
> > > Signed-off-by: Manuel Bouyer <bouyer@xxxxxxxxxx>
> > 
> > Reviewed-by: Roger Pau Monné <roger.pau@xxxxxxxxxx>
> > 
> > If you have a moment might be worth adding a note in
> > xl-network-configuration.5.pod that NetBSD in HVM mode requires
> > bridged networking I think?
> 
> With the default qemu-ifup script only. As you can do whatever you want
> in the script, you can support whatever network configuration you want.
> It's quite easy to do IP routing for example.

Right, but the default script provided will do bridging mode only, and
even if you add 'script=vif-ip' to the network configuration line it
won't do what you expect. Instead it will try to add the tap network
interface to the default xenbr0 bridge.

I'm not opposed to having it this way right now, as it's better to
have this than no support at all, but we should have the shortcoming
documented somewhere. Can be done as a separate patch.

> > 
> > Also, the qemu-ifup script doesn't seem to be part of the NetBSD
> > scripts that are upstream, is this something carried by the NetBSD
> > package?
> 
> Ha maybe I overlooked this. I'll add it, but maybe it can be submitted in
> a separate patch ?

Yes, that's fine, can be added as a separate patch.

Thanks, Roger.