Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf after rc6

Cross-merge BPF and other fixes after downstream PR.

No conflicts.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>

diff --cc arch/s390/net/bpf_jit_comp.c
Simple merge

diff --cc kernel/bpf/helpers.c
Simple merge

diff --cc net/netlink/af_netlink.c
Simple merge

diff --cc tools/lib/bpf/libbpf.c
Simple merge