On 11/4/20 2:28 AM, Jiri Benc wrote: > On Tue, 3 Nov 2020 18:45:59 -0800, Alexei Starovoitov wrote: >> libbpf is the only library I know that is backward and forward compatible. > > This is great to hear. It means there will be no problem with iproute2 > using the system libbpf. As libbpf is both backward and forward > compatible, iproute2 will just work with whatever version it is used > with. That is how I read that as well. The bpf team is making sure libbpf is a stable, robust front-end to kernel APIs. That stability is what controls the user experience. With the due diligence in testing, packages using libbpf can have confidence that using an libbpf API is not going to change release over release regardless of kernel version installed (i.e., as kernel versions go newer from an OS start point - typical scenario for a distribution). > > The only problem would be if a particular function changed its > semantics while retaining ABI. But since libbpf is backward and forward > compatible, this should not happen. exactly. Then, If libbpf needs to change something that affects users, it bumps the soname version.
