This script was expecting only add/remove events which has not been the
case since Kernel 4.12 (which added bind/unbind). Bind events were getting
treated as remove events which would cause hotplugged 3g modems to not
work.
More info:
https://lkml.org/lkml/2018/12/23/128https://github.com/systemd/systemd/issues/8221
Signed-off-by: Arjun AK <arjunak234@gmail.com>
(cherry picked from commit 89ef883b92)