"A digitally signed build of Linux would work, but that would
mean persuading OEMs to include the keys. Disabling the feature
would allow unsigned code to run. However, it is unclear how many
OEMs and firmware vendors will follow this route, which isn't
required for Windows 8 certification.
"The forthcoming secure boot feature has created a huge row with
computer scientists, such as Ross Anderson of Cambridge University
(here), and open-source developers who accuse Microsoft of pushing
lock-in and decreasing consumer choice. Microsoft responded by
saying consumers would continue to control their PC and cited the
example of one OEM, Samsung, which is including a "disable secure
boot" feature on prototype versions of its tablet PC."