Doing a little further research, sometimes there is a *very* good reason to disable SecureBoot: because you are using an older distro, which does not support it. Using the msft-signed shim from mjg (thanks!), it is possible for fedora 18+ and ubuntu 12.10+ to operate with SecureBoot turned on, but lesser distros prolly cannot function with it enabled. (Being UEFI-bootable in general is distinct from the special case of being UEFI-bootable with SecureBoot turned on... Linux has had the former since ~2000, but the latter only started being possible quite recently.)
Along the same lines, your distro needs to be UEFI-bootable, which in particular means that it must be a 64-bit distro, so that it will be compatible with a 64-bit UEFI firmware. Caveat, there are some cases where 32-bit [U?]EFI firmware exists -- cf this post by mjg discussing apple hardware like that -- http://mjg59.dreamwidth.org/26734.html Just because your 64-bit CPU is able to handle running a 32-bit OS, does not mean your 64-bit UEFI will be capable of booting that OS.
There was also some complaining about UEFI firmware only being able to read certain filesystems, with FAT32 being the safest. Presumably this only applies to the bootloader portion of the system (i.e. GRUB) and not to the full OS partitions, but I'm fuzzy here.
It may also be necessary to utilize GPT, rather than MBR, but this is speculative. (Not even touching 4kb-sector-size....)
There are some reports in the wild that support for UEFI-boot varies by the type of boot-device: some boxen will not permit UEFI boot from DVD, but work fine from USB, whereas other boxen will not permit UEFI boot from usb3, but work fine from usb2 (seems backwards to me!). These firmware limitations will prolly resolve themselves at some point, but for now there are known issues.
Does anybody have a definitive list of these sorts of requirements slash limitations, preferably with plenty of gory details?
Re: impedance-matching requirements when booting Linux
Along the same lines, your distro needs to be UEFI-bootable, which in particular means that it must be a 64-bit distro, so that it will be compatible with a 64-bit UEFI firmware. Caveat, there are some cases where 32-bit [U?]EFI firmware exists -- cf this post by mjg discussing apple hardware like that -- http://mjg59.dreamwidth.org/26734.html Just because your 64-bit CPU is able to handle running a 32-bit OS, does not mean your 64-bit UEFI will be capable of booting that OS.
There was also some complaining about UEFI firmware only being able to read certain filesystems, with FAT32 being the safest. Presumably this only applies to the bootloader portion of the system (i.e. GRUB) and not to the full OS partitions, but I'm fuzzy here.
It may also be necessary to utilize GPT, rather than MBR, but this is speculative. (Not even touching 4kb-sector-size....)
There are some reports in the wild that support for UEFI-boot varies by the type of boot-device: some boxen will not permit UEFI boot from DVD, but work fine from USB, whereas other boxen will not permit UEFI boot from usb3, but work fine from usb2 (seems backwards to me!). These firmware limitations will prolly resolve themselves at some point, but for now there are known issues.
Does anybody have a definitive list of these sorts of requirements slash limitations, preferably with plenty of gory details?