Default What's the real problem about linux on surface rt ?

Hi,

I've buy from at lest one mont a surface rt, i've jailbreak it and install filezilla and notepad+++ so.... but i'd like anymore. Like many people i'd like to install a linux distribution on it but i dont really understand what is the problem...

I've know about:
Surface get a secure boot (EFI) and we can't disable the secure boot on surface RT caused windows need a valid key (?). I've read that linux got some distributions arm based (ubuntu, debian, fedora) and i think i've understand about ubuntu got a valid microsoft signature with a ssl provider that can bypass the useless verification... am i right?

So, if ubuntu (or another distro), got a valid sign for bypassing the limitation to due EFI why can't we normal install linux such like surface pro??

Best regards and sry for my bad english ^^'

----------------------------------------------