Andrii Nakryiko 25498a1969 libbpf: Always specify expected_attach_type on program load if supported ... For some types of BPF programs that utilize expected_attach_type, libbpf won't set load_attr.expected_attach_type, even if expected_attach_type is known from section definition. This was done to preserve backwards compatibility with old kernels that didn't recognize expected_attach_type attribute yet (which was added in 5e43f899b0 ("bpf: Check attach type at prog load time"). But this is problematic for some BPF programs that utilize newer features that require kernel to know specific expected_attach_type (e.g., extended set of return codes for cgroup_skb/egress programs). This patch makes libbpf specify expected_attach_type by default, but also detect support for this field in kernel and not set it during program load. This allows to have a good metadata for bpf_program (e.g., bpf_program__get_extected_attach_type()), but still work with old kernels (for cases where it can work at all). Additionally, due to expected_attach_type being always set for recognized program types, bpf_program__attach_cgroup doesn't have to do extra checks to determine correct attach type, so remove that additional logic. Also adjust section_names selftest to account for this change. More detailed discussion can be found in [0]. [0] https://lore.kernel.org/bpf/20200412003604.GA15986@rdna-mbp.dhcp.thefacebook.com/ Fixes: 5cf1e91456 ("bpf: cgroup inet skb programs can return 0 to 3") Fixes: 5e43f899b0 ("bpf: Check attach type at prog load time") Reported-by: Andrey Ignatov <rdna@fb.com> Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Song Liu <songliubraving@fb.com> Acked-by: Andrey Ignatov <rdna@fb.com> Link: https://lore.kernel.org/bpf/20200414182645.1368174-1-andriin@fb.com		2020-04-15 13:22:43 +02:00
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fault-injection	docs: fault-injection: convert docs to ReST and rename to *.rst	2019-06-14 14:21:07 -06:00
ktest	ktest: Fix typos in ktest.pl	2020-03-09 16:15:27 -04:00
kunit	SPDX patches for 5.7-rc1.	2020-04-03 13:12:26 -07:00
nvdimm	remove ioremap_nocache and devm_ioremap_nocache	2020-01-06 09:45:59 +01:00
radix-tree	SPDX patches for 5.7-rc1.	2020-04-03 13:12:26 -07:00
scatterlist	treewide: Add SPDX license identifier - Makefile/Kconfig	2019-05-21 10:50:46 +02:00
selftests	libbpf: Always specify expected_attach_type on program load if supported	2020-04-15 13:22:43 +02:00
vsock	SPDX patches for 5.7-rc1.	2020-04-03 13:12:26 -07:00