Quoting Aleksandar Milivojevic alex@milivojevic.org:
I've just updated one machine from 4.0 to 4.2. The trouble is, the new kernel doesn't want to boot (2.6.9-22.EL, also tested 2.6.9.22.0.2.EL). Usually, manually recreating initrd file solved this problem in the past for me. But not this time.
Playing around, I also noticed that if I rebuild initrd for the old kernel, then it also fails to boot. The only way to boot it up is using the original initrd image created when the system was initally installed.
....
Well, found where the problem is. Current version of mkinitrd seems to have some nasty habits... In case anybody else gets hit by this problem, try downgrading mkinitrd:
https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=164423
---------------------------------------------------------------- This message was sent using IMP, the Internet Messaging Program.