DO NOT UPGRADE YOUR DEDICATED SERVER WITH THIS KERNEL. THIS WILL MAKE YOUR SERVER UNBOOTABLE.
The warning above is for customers running CentOS 6 on dedicated servers. VPS users are not affected by the kernel change (since the OpenVZ VPSes use the kernel of the host node).
The CentOS team is aware of this bug and will work on a fix. Here is the entry from the CentOS bug tracker - http://bugs.centos.org/view.php?id=6831
update: CentOS has released a new kernel package which resolves this problem. It may take some time before the new packages are synced to all the CentOS mirrors.
Here is the official CentOS announcement - http://lists.centos.org/pipermail/centos-announce/2013-December/020075.html
Friday, December 13, 2013