console freeze after upgrading VM OS from RHEL 6.1 to RHEL 6.4/6.6

Hi ,

I am facing an issue where we have an application running on Guest VM ( RHEL 6.1 ). We needed upgrade the OS from RHEL6.1 to RHEL 6.4.
So, we did the upgrade of the VM by attaching RHEL6.4 ISO as CD-ROM device and running the standard OS upgrade. After the OS upgrade is done.
When VM boots up Guest console freezes just before the login screen as show in the below screenshot:

Here, I can login to guest via ssh/telnet but, from console I can't login or do any operation. I tried pressing CTR+ALT+DEL VM get's rebooted but again the console just freeze at this step.
I also tried the suspend and then resume option (found workaround on some forums)

When searched google got some WA but did not worked.
can someone help.