Photos on iOS 11 re-uploading entire library to iCloud
If you go to a computer and log in to http://iCloud.com/photos you will be able to see the status of your library as rendered from Apple’s servers in the data center.

If your cloud library is corrupt, you can either:


try and delete it and let it clear up and try a sync up from the one device that has your master copy / most complete library
work with support to convince tier 1 support that you’ve read the instructions and don’t need basic training and need an engineer to look at your account on the server side


If your cloud library isn’t corrupt, you can then decide to wait out the sync or wipe that device and start the iCloud sync over. I’ve had times where things are blank and syncing for three to four days and it clear up so you might need do nothing but connect to WiFi and connect the device to power for a few 8 hour periods to let all the sync / upload / duplicate processes to run.

You might have something the code can’t resolve and need to get Tier 1 to refer you to engineering since Apple doesn’t let people contact iCloud engineering directly and you do need to work through support to get there if needed.