Modem Manager in LXC

Hello,

I’m trying to use modemmanager into a container, my LXD config is
devices:
SierraW:
productid: a001
type: usb
vendorid: “1199”
bond0.99:
nictype: macvlan
parent: bond0.99
type: nic
cdc-wdm0:
gid: “20”
mode: “0666”
path: /dev/cdc-wdm0
source: /dev/cdc-wdm0
type: unix-char
ttyACM0:
gid: “20”
mode: “0666”
path: /dev/ttyACM0
source: /dev/ttyACM0
type: unix-char

Modem Manager start reconize the modem, but the problem is with the MBIM attached network interface : wwan0

ModemManager[1168]: [1599153947.316470] Modem (Sierra) ‘/sys/devices/pci0000:00/0000:00:14.0/usb1/1-2’ completely disposed
ModemManager[1168]: [1599153947.316502] Couldn’t create modem for device ‘/sys/devices/pci0000:00/0000:00:14.0/usb1/1-2’: Failed to find a net port in the MBIM modem

After investigations, I think it’s because of missing …/net/wwan0 inside container who link cdc interface to wwan0, in host :

ll /sys/devices/pci0000:00/0000:00:14.0/usb1/1-2/1-2:1.0/net/wwan0/
total 0
drwxr-xr-x 6 root root 0 août 28 11:50 ./
drwxr-xr-x 3 root root 0 août 28 11:50 …/
-r–r--r-- 1 root root 4096 août 28 11:50 addr_assign_type
-r–r--r-- 1 root root 4096 août 28 11:50 address
-r–r--r-- 1 root root 4096 sept. 3 18:45 addr_len
-r–r--r-- 1 root root 4096 sept. 3 18:45 broadcast
-rw-r–r-- 1 root root 4096 sept. 3 18:45 carrier
-r–r--r-- 1 root root 4096 sept. 3 18:45 carrier_changes
-r–r--r-- 1 root root 4096 sept. 3 18:45 carrier_down_count
-r–r--r-- 1 root root 4096 sept. 3 18:45 carrier_up_count
drwxr-xr-x 2 root root 0 sept. 3 18:27 cdc_ncm/
lrwxrwxrwx 1 root root 0 sept. 3 12:02 device -> …/…/…/1-2:1.0/
-r–r--r-- 1 root root 4096 sept. 3 18:45 dev_id
-r–r--r-- 1 root root 4096 août 28 11:50 dev_port
-r–r--r-- 1 root root 4096 sept. 3 18:45 dormant
-r–r--r-- 1 root root 4096 sept. 3 18:45 duplex
-rw-r–r-- 1 root root 4096 sept. 3 18:45 flags
-rw-r–r-- 1 root root 4096 sept. 3 18:45 gro_flush_timeout
-rw-r–r-- 1 root root 4096 sept. 3 18:45 ifalias
-r–r--r-- 1 root root 4096 août 28 11:50 ifindex
-r–r--r-- 1 root root 4096 août 28 11:50 iflink
-r–r--r-- 1 root root 4096 sept. 3 18:45 link_mode
-rw-r–r-- 1 root root 4096 sept. 3 18:45 mtu
-r–r--r-- 1 root root 4096 août 28 11:50 name_assign_type
-rw-r–r-- 1 root root 4096 sept. 3 18:45 netdev_group
-r–r--r-- 1 root root 4096 sept. 3 18:45 operstate
-r–r--r-- 1 root root 4096 sept. 3 18:45 phys_port_id
-r–r--r-- 1 root root 4096 août 28 11:50 phys_port_name
-r–r--r-- 1 root root 4096 sept. 3 18:45 phys_switch_id
drwxr-xr-x 2 root root 0 sept. 3 18:27 power/
-rw-r–r-- 1 root root 4096 sept. 3 18:45 proto_down
drwxr-xr-x 4 root root 0 août 28 11:50 queues/
-r–r--r-- 1 root root 4096 sept. 3 18:45 speed
drwxr-xr-x 2 root root 0 sept. 3 18:27 statistics/
lrwxrwxrwx 1 root root 0 août 28 11:50 subsystem -> …/…/…/…/…/…/…/…/class/net/
-rw-r–r-- 1 root root 4096 sept. 3 18:45 tx_queue_len
-r–r--r-- 1 root root 4096 août 28 11:50 type
-rw-r–r-- 1 root root 4096 août 28 11:50 uevent
lrwxrwxrwx 1 root root 0 sept. 3 19:26 upper_mac11bacffd -> …/…/…/…/…/…/…/virtual/net/mac11bacffd/

in container :
ll /sys/devices/pci0000:00/0000:00:14.0/usb1/1-2/net
ls: cannot access ‘/sys/devices/pci0000:00/0000:00:14.0/usb1/1-2/net’: No such file or directory

wwan0 is attached as physical type

LXD is in 4.4

How can I continue my setup ?

Regards

Nicolas F.