Searching the Internet, you can find posts and discussions stating that the 850 EVO had problems on Linux (related to the TRIM features reported by the firmware not being accurate IIRC), which caused it to be blacklisted for TRIM.
I've been unable to find a confirmation of the 850 EVO being fine for current Ubuntu versions, nor if TRIM is now fully functional on it or not.
Are there any news regarding this SSD?