Merge branch 'bpf-global-funcs'

Alexei Starovoitov says:

====================
Introduce static vs global functions and function by function verification.
This is another step toward dynamic re-linking (or replacement) of global
functions. See patch 2 for details.

v2->v3:
- cleaned up a check spotted by Song.
- rebased and dropped patch 2 that was trying to improve BTF based on ELF.
- added one more unit test for scalar return value from global func.

v1->v2:
- addressed review comments from Song, Andrii, Yonghong
- fixed memory leak in error path
- added modified ctx check
- added more tests in patch 7
====================

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

1 files changed, 15 insertions, 0 deletions

diff --git a/tools/testing/selftests/bpf/progs/fexit_bpf2bpf.c b/tools/testing/selftests/bpf/progs/fexit_bpf2bpf.c
index 2d211ee98a1c..81d7b4aaf79e 100644
--- a/tools/testing/selftests/bpf/progs/fexit_bpf2bpf.c
+++ b/tools/testing/selftests/bpf/progs/fexit_bpf2bpf.c
@@ -79,4 +79,19 @@ int test_subprog2(struct args_subprog2 *ctx)
 	test_result_subprog2 = 1;
 	return 0;
 }
+
+__u64 test_result_subprog3 = 0;
+BPF_TRACE_3("fexit/test_pkt_access_subprog3", test_subprog3,
+	    int, val, struct sk_buff *, skb, int, ret)
+{
+	int len;
+
+	__builtin_preserve_access_index(({
+		len = skb->len;
+	}));
+	if (len != 74 || ret != 74 * val || val != 3)
+		return 0;
+	test_result_subprog3 = 1;
+	return 0;
+}
 char _license[] SEC("license") = "GPL";