[$] Code signing for BPF programs

The Linux kernel can be configured so thatkernel modules must be signed orotherwise authenticated to be loadedinto the kernel. Some BPF developers want that to be an option for BPF programsas well - after all, if those are going to run as part of the kernel,they should be subject to the same code-signing requirements. Blaise Boscaccyand Cong Wang presented two different visions for how BPF code signing couldwork at the 2025 Linux Storage, Filesystem, Memory-Management, and BPF Summit.