Circular view path [login]: would dispatch back to the current handler URL [/login] again.

org.springframework.web.servlet.view.InternalResourceView.prepareForRendering(InternalResourceView.java:209)org.springframework.web.servlet.view.InternalResourceView.prepareForRendering(InternalResourceView.java:209)

application.yml 파일에서 mvc:view:prefix:suffix 를 다시 확인하여야 함

이 경우에는 application.yml 은 계층형 파일이므로 
# Spring properties
spring:
   main:
     allow-bean-definition-overriding: true
    
# JSP
mvc:
   view:
     prefix: /WEB-INF/jsp/
     suffix: .jsp

mvc를 spring보다 더 들여써주어야 함