systemd/debian/udev.prerm

#!/bin/sh -e

# adapted from postinst
chrooted() {
  if [ "$(stat -c %d/%i /)" = "$(stat -Lc %d/%i /proc/1/root 2>/dev/null)" ];
  then
    return 1
  fi
  return 0
}

kill_udevd() {
    start-stop-daemon --stop --name udevd --user root --oknodo --quiet --retry 5
}

case "$1" in
    remove|deconfigure|failed-upgrade)
    if ! chrooted; then
      kill_udevd
    fi
    ;;

    upgrade)
    ;;

    *)
    echo "$0 called with unknown argument '$1'" >&2
    exit 1
    ;;
esac

#DEBHELPER#