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I'm not arguing against eBPF the language. It's safety guarantees make sense to me.

I'm arguing against the in-kernel eBPF infrastructure: bpf system call, the JIT and the VM.

I think it makes more sense to just compile eBPF (or rust or whatever safe language you want) to a kernel module.

The idea with having eBPF in the kernel is that we can limit the amount of trust given to a particular user-space task.

Accepting compiled stuff in the form of a kernel module requires root privileges and requires that the kernel essentially have complete trust in the code being loaded.

Loading eBPF eliminates the need to trust the process/user doing the loading to that level.

The bpf() system call and SOCK_RAW both require root. Is there an example of using bpf that doesn't require root?

The BPF syscalls don't require cap sys admin. Only specific invocations. You can setup a socket filter without sys admin, and a device or XDP filter with net admin.

Sure but how common is that case? How common are multi-tenant Linux systems with untrusted users that give those specific permissions? Do you want untrusted users sniffing the packets of others?

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