How to fix leap second sleep issue without reboot
Is your system time synched with ntpd or ptp? If not, update your tzdata package.
For systems not synchronized by ntpd or ptp an updated tzdata package that contains the December 31st leap second is required. The updated tzdata package was released as part of RHEA-2016-1982, and any systems using RHEL 7 that are not synchronized by ntpd or ptp should update to tzdata-2016g-2.el7, or a later version, to receive this fix.
Resolve Leap Second Issues in Red Hat Enterprise Linux