Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

Alexei Starovoitov says:

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pull-request: bpf-next 2019-06-19

The following pull-request contains BPF updates for your *net-next* tree.

The main changes are:

1) new SO_REUSEPORT_DETACH_BPF setsocktopt, from Martin.

2) BTF based map definition, from Andrii.

3) support bpf_map_lookup_elem for xskmap, from Jonathan.

4) bounded loops and scalar precision logic in the verifier, from Alexei.
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Signed-off-by: David S. Miller <davem@davemloft.net>