Re: [PATCH bpf-next 1/4] xdp: Support specifying expected existing program when attaching XDP

Jakub Kicinski
2020-03-24T18:53:53Z

On Tue, 24 Mar 2020 11:57:45 +0100 Toke Høiland-Jørgensen wrote:
> > If everyone is using libbpf, does kernel system (bpf syscall vs
> > netlink) matter all that much?
>
> This argument works the other way as well, though: If libbpf can
> abstract the subsystem differences and provide a consistent interface to
> "the BPF world", why does BPF need to impose its own syscall API on the
> networking subsystem?

Hitting the nail on the head there, again :)

Once upon a time when we were pushing for libbpf focus & unification,
one of my main motivations was that a solid library that most people
use give us the ability to provide user space abstractions.

As much as adding new kernel interfaces "to rule them all" is fun, it
has a real cost.