Install Ubuntu 12.10 on UEFI along Windows 8

Question

Hello I want to install Ubuntu 12.10 on an UEFI machine with manual partitioning.

1. Do I have to disable "Secure Boot"?
2. Do I have to create a 2nd ESP (EFI System Partition) for Ubuntu?
3. Do I have to give it the boot flag?
4. Do I have to set mount point /boot/efi?
5. Do I have to install grub on /dev/sda?

I am used to BIOS installation where:

• /dev/sda1 100 MB Windows 7 hidden System Partition
• /dev/sda2 200 GB Windows 7 C:\ Drive
• /dev/sda3 115 GB Linux Ext4 Root
• /dev/sda4 2 GB Linux Swap
• grub-install /dev/sda
• update-grub

Answer 1

1. In theory, no, you don't need to disable Secure Boot; Ubuntu 12.10 includes Secure Boot support. In practice, this feature is still new enough that it may not work reliably on all systems.
2. No, you don't need a second ESP; Ubuntu should be able to share a single ESP with Windows (or any other OS). In fact, sharing an ESP is the way it's supposed to work (although multiple ESPs are also legal).
3. The "boot flag" is simply libparted's (and therefore GParted's and parted's) way of identifying an ESP.
4. In principle, you can mount your ESP anywhere you like, or not at all. In practice, some tools may require the ESP to be mounted at /boot/efi. This would be most important for GRUB package updates, but some other tools might need this, too.
5. In an EFI system, GRUB doesn't install any code directly to the hard disk's MBR, although of course code does go on the hard disk -- just in the ESP. Thus, installing GRUB on /dev/sda doesn't really make sense. That said, some user interfaces may refer to doing so because they haven't been properly updated for the EFI case. (I'm not sure what Ubuntu 12.10's state is on this score, offhand.)