[systemd-devel] No device unit created

[jean-philippe francois]

Hi,

I have a problem I don't know how to debug.
The documentation for device units says :

systemd will dynamically create device units for all kernel devices
that are marked with the "systemd" udev tag

Howevever, while the device I am waiting for are given the systemd
tag, it seems no device unit is ever created.
This is on an embedded machine, and systemd has been configured like this :

systemd 220 running in system mode. (-PAM -AUDIT -SELINUX -IMA
-APPARMOR -SMACK -SYSVINIT -UTMP -LIBCRYPTSETUP -GCRYPT -GNUTLS -ACL
-XZ -LZ4 -SECCOMP +BLKID -ELFUTILS +KMOD -IDN)

For instance with wlan0 :

/ # udevadm info -p /sys/class/net/wlan0
P: /devices/platform/omap_hsmmc.1/mmc_host/mmc1/mmc1:0001/mmc1:0001:1/net/wlan0
E: DEVPATH=/devices/platform/omap_hsmmc.1/mmc_host/mmc1/mmc1:0001/mmc1:0001:1/net/wlan0
E: ID_NET_DRIVER=unifi
E: ID_NET_LINK_FILE=/lib/systemd/network/99-default.link
E: ID_NET_NAME_MAC=enx000780608459
E: ID_PATH=platform-omap_hsmmc.1
E: ID_PATH_TAG=platform-omap_hsmmc_1
E: IFINDEX=2
E: INTERFACE=wlan0
E: SUBSYSTEM=net
E: SYSTEMD_ALIAS=/sys/subsystem/net/devices/wlan0
E: TAGS=:systemd:
E: USEC_INITIALIZED=14096986

And now the systemd vision :

/ # systemctl status sys-subsystem-net-devices-wlan0.device
* sys-subsystem-net-devices-wlan0.device
   Loaded: loaded
   Active: inactive (dead)

Jan 01 00:01:36 xcam- systemd[1]:
sys-subsystem-net-devices-wlan0.device: Job
sys-subsystem-net-devices-wlan0.device/start timed out.
Jan 01 00:01:36 xcam- systemd[1]: Timed out waiting for device
sys-subsystem-net-devices-wlan0.device.

However if I try an inexistant device, I have the same status

/ # systemctl status dev-tagada.device
* dev-tagada.device
   Loaded: loaded
   Active: inactive (dead)

systemd-udevd is up and running :

/ # systemctl status systemd-udevd
* systemd-udevd.service - udev Kernel Device Manager
   Loaded: loaded (/lib/systemd/system/systemd-udevd.service; static;
vendor preset: enabled)
   Active: active (running) since Thu 1970-01-01 00:00:08 UTC; 47min ago
     Docs: man:systemd-udevd.service(8)
           man:udev(7)
 Main PID: 782 (systemd-udevd)
   CGroup: /system.slice/systemd-udevd.service
           `-782 /lib/systemd/systemd-udevd

Jan 01 00:00:08 xcam- systemd[1]: Starting udev Kernel Device Manager...
Jan 01 00:00:08 xcam- systemd-udevd[782]: specified group 'input' unknown
Jan 01 00:00:08 xcam- systemd-udevd[782]: specified group 'audio' unknown
Jan 01 00:00:08 xcam- systemd-udevd[782]: starting version 220
Jan 01 00:00:08 xcam- systemd[1]: Started udev Kernel Device Manager.


Can you help me with this ?

Regards,
Jean-Philippe Francois