microcode: CPU0 update to revision 0x710 failed
microcode: CPU1 update to revision 0x710 failed
microcode: CPU2 update to revision 0x710 failed
microcode: CPU3 update to revision 0x710 failed
microcode: CPU4 update to revision 0x710 failed
microcode: CPU5 update to revision 0x710 failed
microcode: CPU6 update to revision 0x710 failed
microcode: CPU7 update to revision 0x710 failed

As title, my CentOS 6.4 is giving me this error at boot after some yum updates.
What is happening?

It looks like CentOS/RHEL released the following update :

https://rhn.redhat.com/errata/RHEA-2013-1202.html

It is an Intel microcode update, I believe for a security issue in Intel CPU's found recently. Since you are running a virtual box, it can't do the microcode update. You can find a solution at :

https://forums.oracle.com/thread/2316586

(Oracle Linux is also based on RHEL, so it should work).

Gary Thorne

you mean that I can safely remove microcode_ctl ???

yum remove microcode_ctl

I just tested this on a CentOS 6.4 test box. I installed microcode_ctl, verified it was working in dmesg, and then erased the package. Everything appears to work fine.

Gary Thorne