Re: I have a OnePlus One and lost root with OTA from 4.4.4 to 5.0.2 (
You root the ROM, not the phone. So you rooted the 4.4.4 ROM. Then you replaced it with the 5.0.2 ROM, which wasn't rooted. You'll have to find a root method for 5.0.2. (Super SU doesn't root the phone, it controls which apps can get root access. It's the binary, su, that provides root access, and you can only install that if you're rooted, so someone has to figure out how to get the 17L ROM to "accidentally" be rooted temporarily, so the program or app can copy su over to the phone. You can install SuperSU from the Play Store but, as I said, that won't root the phone, it'll only control which apps can get root access - if you have su installed.