Netplan replug function is incompatible with ath9k_htc module

[Nicolino Curalli]

Hi all,

we ( my work team and I ) are porting an allwinner H3 with wireless chip  Atheros AR9271 to Ubuntu Core 16.

We hit the following problem about the interaction  between netplan  and the ath9k_htc module, controlling the chip Atheros AR9271.

If you run the following command

    netplan --debug apply

or  you use console-conf for setting the network interfaces we get the following messages :

** (generate:2261): DEBUG: Processing input file //etc/netplan/00-snapd-config.yaml..
** (generate:2261): DEBUG: eth0: setting default backend to 1
** (generate:2261): DEBUG: Generating output files..
** (generate:2261): DEBUG: NetworkManager: definition eth0 is not for us (backend 1)
DEBUG:netplan generated networkd configuration exists, restarting networkd
DEBUG:no netplan generated NM configuration exists
DEBUG:device lo operstate is unknown, not replugging
DEBUG:device eth0 operstate is up, not replugging
DEBUG:replug wlan0: unbinding 4-1:1.0 from /sys/bus/usb/drivers/ath9k_htc
DEBUG:replug wlan0: rebinding 4-1:1.0 to /sys/bus/usb/drivers/ath9k_htc

The last two row show two consecutive actions, one soon after the other:  unbind and bind the usb device on usb hub.

The module ath9k_htc doesn't work fine in this situation: the wireless interface disappears.

Our problem can be fixed by using the same approcch used for mac80211_hwsim e mwifiex_pcie modules. We had a look at the netplan code.

Our problem is testing our simple patch before open the bug report for netplat project: the problematic file is src/netplan.

How can we repack a core snap with different code per netplan?

How long does it take to have a patch like this to be accepted in core snap code?

Cheers,

Nicolino