After installation of the latest hplip package (for HP printer support on GNU/Linux systems) you might see boot warnings like this:
udevd[281]: SYSFS{}= will be removed in a future udev version, please use ATTR{}= to match the event device, or ATTRS{}= to match a parent device, in /etc/udev/rules.d/86-hpmud-hp_laserjet_p1008.rules:6
To fix the problem I did this (on a Debian system):
sudo sed -i -e "s|SYSFS|ATTRS|g" -e "s|sysfs|attrs|g" /etc/udev/rules.d/*hpmud*.rules
Oleander Donovan's IT blog 