[arch-dev-public] [signoff] udev-168-1

[Tom Gundersen]

Upstream update.
Please signoff both.


udev 168
========
Bugfixes.

Udev logs a warning now if /run is not writable at udevd
startup. It will still fall back to /dev/.udev, but this is
now considered a bug.

The running udev daemon can now cleanly shut down with:
  udevadm control --exit

Udev in initramfs should clean the state of the udev database
with: udevadm info --cleanup-db which will remove all state left
behind from events/rules in initramfs. If initramfs uses
--cleanup-db and device-mapper/LVM, the rules in initramfs need
to add OPTIONS+="db_persist" for all dm devices. This will
prevent removal of the udev database for these devices.

Spawned programs by PROGRAM/IMPORT/RUN now have a hard timeout of
120 seconds per process. If that timeout is reached the spawned
process will be killed. The event timeout can be overwritten with
udev rules.

If systemd is used, udev gets now activated by netlink data.
Systemd will bind the netlink socket which will buffer all data.
If needed, such setup allows a seemless update of the udev daemon,
where no event can be lost during a udevd update/restart.
Packages need to make sure to: systemctl stop udev.socket udev.service
or 'mask' udev.service during the upgrade to prevent any unwanted
auto-spawning of udevd.
This version of udev conflicts with systemd version below 25. The
unchanged service files will not wirk correctly.