When the Hypervisor configures the boot menu for EFI it extracts the CDLABEL from the isolinux.cfg file. The entry in the file contains a period ('.'), which is not matched correctly by the regular expression used to extract the CDLABEL. As a result the kernel parameters generated contained an invalid CDLABEL, resulting in a kernel panic. The regular expression used to extract the CDLABEL has been updated to do so correctly.