How does don quixote mock books of chivlary and how does it defend them?

From the novel;

obsession- "he so immersed himself in those romances that he spent whole days and nights over his books; and thus with little sleeping and much reading his brains dried up to such a degree that he lost the use of his reason" (Book 1, Part 1).

why he wanted to become a knight-

"he was spurred on by the conviction that the world needed his immediate presence." (Book 1, Part 2).

"the order of knight-errantry was instituted to defend maidens, to protect widows, and to rescue orphans and distressed persons," the knight continues (Book 1, Part 8).