After upgrading RHEL version from 5.9 to 5.10 or from 6.4 to 6.5 the system hangs on "Restarting system / machine restart" when reboot is issued

Issue

• After upgrading from RHEL 5.9 to 5.10 system hangs during reboot, following are the last few messages on the console:

Restarting system
.
machine restart

• After upgrading from RHEL 6.4 to 6.5 system hangs during reboot, following are the last few messages on the console:

Please stand by while rebooting the system...
Restarting system.

• The system also locks up on the reboot after booting in the older kernel.