Subject: Re: [RFC PATCH bpf-next 6/8] libbpf: allow specifying map definitions using BTF

From: Stanislav Fomichev <[email-masked]>
Date: Tue, 4 Jun 2019 06:45:38 -0700

On 06/03, Stanislav Fomichev wrote:
> > BTF is mandatory for _any_ new feature.
> If something is easy to support without asking everyone to upgrade to
> a bleeding edge llvm, why not do it?
> So much for backwards compatibility and flexibility.
> 
> > It's for introspection and debuggability in the first place.
> > Good debugging is not optional.
> Once llvm 8+ is everywhere, sure, but we are not there yet (I'm talking
> about upstream LTS distros like ubuntu/redhat).
But putting this aside, one thing that I didn't see addressed in the
cover letter is: what is the main motivation for the series?
Is it to support iproute2 map definitions (so cilium can switch to libbpf)?
If that's the case, maybe explicitly focus on that? Once we have
proof-of-concept working for iproute2 mode, we can extend it to everything.