"Permanent fix" refers to a solution or resolution that is meant to last or endure for a long period of time without needing further adjustments or repair. Full definition
A more permanent fix will require significant changes across the board — the circuit board, that is. (techcrunch.com)
While permanent fixes tend to involve things like surgery, lifestyle changes, and figuring out what you're anxious about; treatment of symptoms tends to involve pills. (firstthings.com)
But it can also be permanent fixed payment for the life of policy. (en.wikipedia.org)