Subject: Re: [RFC PATCH net-next 0/3] Make the PHY library stop being so greedy when binding the generic PHY driver

From: Andrew Lunn <[email-masked]>
Date: Fri, 3 Sep 2021 21:56:01 +0200

On Fri, Sep 03, 2021 at 07:58:50PM +0100, Russell King (Oracle) wrote:
> On Fri, Sep 03, 2021 at 07:21:19PM +0200, Andrew Lunn wrote:
> > Hi Russell
> > 
> > Do you have
> > 
> > auto brdsl
> > 
> > in your /etc/network/interfaces?
> > 
> > Looking at /lib/udev/bridge-network-interface it seems it will only do
> > hotplug of interfaces if auto is set on the bridge interface. Without
> > auto, it only does coldplug. So late appearing switch ports won't get
> > added.
> 
> I think you're looking at this:
> 
> [ "$BRIDGE_HOTPLUG" = "no" ] && exit 0
> 
> ?

No, i was meaning this bit:

   for i in $(ifquery --list --allow auto); do
        ports=$(ifquery $i | sed -n -e's/^bridge[_-]ports: //p')

Inside this is the actual adding of the interface to the bridge:

                                        brctl addif $i $port && ip link set dev $port up

$ /sbin/ifquery --list --allow auto
lo
eth0
br42

I have various tap interfaces for VMs which get added to br42 when
they appear.

     Andrew