Post Syndicated from original https://lwn.net/Articles/921088/

The BPF subsystem exposes many aspects of the kernel’s internal algorithms
and data structures; this naturally leads to concerns about maintaining
interface stability as the kernel changes. The longstanding position that
BPF offers no interface-stability guarantees to user space has always
seemed a little questionable; kernel developers have, in the past, found
themselves having to maintain interfaces that were not intended to be
stable. Now the BPF community is starting to think about what it might
mean to provide explicit stability promises for at least some of its
interfaces.