Macbook pro's boot in EFI mode, whereas the bootcamp loader emulates a legacy bios in order to boot windows.
This is not the best solution for installing ubuntu 13.10 to a mac, as it can be handled natively in efi mode via grub2, or if you prefer refind.
- Decide on a bootloader that will manage your operating systems. I suggest grub as it can be repaired in the event of problems using the boot-repair app (which works very well with my mac5,5), and it can detect your OSX/Windows partitions. Alternatively as already mentioned refind is an elegant solution for mac's.
- Follow the steps here to get a live USB working for your mac, then hold 'alt' on boot. This should give you the option to boot and install ubuntu in EFI mode.
- When installing select the 'something else' option to partition your disk. Ensure you only install the grub bootloader to the partition of your ubuntu installation.
- Refind will detect a linux partition automatically, however if you have opted for grub you may (as in my case)
need to run boot-repair from the live usb.
To download the boot-repair you will need to enable networking (use the proprietary driver to get this up and running on the macbook):
open a new Terminal, then type:
$ sudo add-apt-repository ppa:yannubuntu/boot-repair && sudo apt-get update
$ sudo apt-get install -y boot-repair && (boot-repair &)
Follow the instructions, then reboot. You should now have ubuntu working natively on the macbook pro.
Good luck, I hope this helps.