Sure, here is the official guidance: https://kernel.org/doc/html//next/process/coding-assistants.html
And here is a search that finds some of the AI commits: https://github.com/search?q=repo%3Atorvalds%2Flinux+%22Assisted-by%22&type=commits
And here is an interview with Linus Torvalds, where he says he's a huge believer in AI and explains how it makes work on the kernel easier: https://www.youtube.com/watch?v=S-_8YliVS4E