Technically because of Skyward Sword, we know that the sword, *ahem* Fi was put to rest while Demise decays from within the sword. Now since Fi hasn't returned since Skyward Sword, this means that the Master Sword has yet to truly be awake in any game that occurs in the timelines after it. So it is safe to say that the master sword has indeed been put to rest for eternity, as it was never awake even during ALttP. At best you can call the times where the Master Sword was used without activating Fi a sort of light sleep like when you are semi-conscious of whats going on around you but you aren't aware enough to wake up. Not even Calamity Ganon could arouse the spirit of the sword, Fi, from her slumber. I'd hate to see the dire straights that could.