From 4ce150b6a412f14074400eac5fc39d1a71c4ef0a Mon Sep 17 00:00:00 2001 From: Ilya Leoshkevich Date: Thu, 12 Sep 2019 18:05:43 +0200 Subject: selftests/bpf: add bpf-gcc support Now that binutils and gcc support for BPF is upstream, make use of it in BPF selftests using alu32-like approach. Share as much as possible of CFLAGS calculation with clang. Fixes only obvious issues, leaving more complex ones for later: - Use gcc-provided bpf-helpers.h instead of manually defining the helpers, change bpf_helpers.h include guard to avoid conflict. - Include for __always_inline. - Add $(OUTPUT)/../usr/include to include path in order to use local kernel headers instead of system kernel headers when building with O=. In order to activate the bpf-gcc support, one needs to configure binutils and gcc with --target=bpf and make them available in $PATH. In particular, gcc must be installed as `bpf-gcc`, which is the default. Right now with binutils 25a2915e8dba and gcc r275589 only a handful of tests work: # ./test_progs_bpf_gcc # Summary: 7/39 PASSED, 1 SKIPPED, 98 FAILED The reason for those failures are as follows: - Build errors: - `error: too many function arguments for eBPF` for __always_inline functions read_str_var and read_map_var - must be inlining issue, and for process_l3_headers_v6, which relies on optimizing away function arguments. - `error: indirect call in function, which are not supported by eBPF` where there are no obvious indirect calls in the source calls, e.g. in __encap_ipip_none. - `error: field 'lock' has incomplete type` for fields of `struct bpf_spin_lock` type - bpf_spin_lock is re#defined by bpf-helpers.h, so its usage is sensitive to order of #includes. - `error: eBPF stack limit exceeded` in sysctl_tcp_mem. - Load errors: - Missing object files due to above build errors. - `libbpf: failed to create map (name: 'test_ver.bss')`. - `libbpf: object file doesn't contain bpf program`. - `libbpf: Program '.text' contains unrecognized relo data pointing to section 0`. - `libbpf: BTF is required, but is missing or corrupted` - no BTF support in gcc yet. Signed-off-by: Ilya Leoshkevich Cc: Jose E. Marchesi Signed-off-by: Daniel Borkmann --- tools/testing/selftests/bpf/progs/test_tc_edt.c | 1 + 1 file changed, 1 insertion(+) (limited to 'tools/testing/selftests/bpf/progs/test_tc_edt.c') diff --git a/tools/testing/selftests/bpf/progs/test_tc_edt.c b/tools/testing/selftests/bpf/progs/test_tc_edt.c index 3af64c470d64..0961415ba477 100644 --- a/tools/testing/selftests/bpf/progs/test_tc_edt.c +++ b/tools/testing/selftests/bpf/progs/test_tc_edt.c @@ -2,6 +2,7 @@ #include #include #include +#include #include #include #include -- cgit v1.2.3-59-g8ed1b