Yup, here's a good read if you get the chance. https://riscv.org/blog/risc-v-upstreaming/

Also if you'd like to start in the middle this is interesting as well https://www.sifive.com/blog/all-aboard-part-7-entering-and-exiting-the-linux-kernel-on-risc-v

Also RUST is a lot easier to implement on RISC-V hardware, and I would suggest it as it's more memory safe on most hardware, especially since often a user can get to Ring 0 with little trouble

https://github.com/xiaoyang-sde/rust-kernel-riscv