The GNU Tools Cauldron is almost entirely focused on user-space tools, but kernel developers need a solid toolchain too. In what appears to be a developing tradition (started in 2024), some kernel developers attended the 2025 Cauldron for the second year in a row to discuss their needs with the assembled toolchain developers. Topics covered in this year's gathering include Rust, better BPF type format (BTF) support, SFrame, and more.