It is a $100 once to get a new key, not $100 per system. But the new Linux LF loader uses hashes and Matthew Garrett says he plans to merge his shim with the Microsoft key, that Ubuntu & Redhat currently use with the LF loader version that uses hash. But that requires the next version of the kernel and release of all the changes to grub. Will not be in 13.04.
UEFI boot install & repair info - Regularly Updated : https://ubuntuforums.org/showthread.php?t=2147295 Please use Thread Tools above first post to change to [Solved] when/if answered completely.
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