First, a little background info: I intended to install Ubuntu alongside OS X, but I accidentally erased my entire hard drive and was left with Ubuntu alone. Yesterday, I finally tried to create a desperate partition and OS X. I successfully shrank my Ubuntu partition and created ~40 GB of free space. I used gparted to do this. At first I tried to use Internet Recovery to install OS X on the unallocated space I had created, but discovered I couldn't. I went back to gparted and created a FAT partition with that space. I'm pretty sure I actually did this using my Ubuntu partition on my hard drive (the one I had just shrunken), rather than the USB live boot I had used to shrink it. Therefore, at this point, I think my Ubuntu partition was still functioning properly. I went back to internet recovery and used disk utility to turn the FAT partition into a Mac OS Extended (Journaled) [HFS/HFS+] partition. I believe this is probably where the problem occurred. I successfully reinstalled OS X and found it to be fully functioning. However, when I tried to boot back into the Ubuntu partition all I got was a black screen with a little white cursor (it looks similar to a terminal screen/the Mac DFU mode, but I can't type anything into it. Is there anything I can do to repair my Ubuntu partition? If not, can I at least recover the data from it? Thank you for any help.