selftests/bpf: Print unexpected output on fail

This makes it easier to debug off-hand when the error message isn't
exactly as expected.

Signed-off-by: Joe Stringer <joe@wand.net.nz>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

diff --git a/tools/testing/selftests/bpf/test_verifier.c b/tools/testing/selftests/bpf/test_verifier.c
index c0f16e9..6cf9bd6 100644 (file)
--- a/tools/testing/selftests/bpf/test_verifier.c
+++ b/tools/testing/selftests/bpf/test_verifier.c
@@ -11291,7 +11291,8 @@ static void do_test_single(struct bpf_test *test, bool unpriv,
                        goto fail_log;
                }
                if (!strstr(bpf_vlog, expected_err) && !reject_from_alignment) {
-                       printf("FAIL\nUnexpected error message!\n");
+                       printf("FAIL\nUnexpected error message!\n\tEXP: %s\n\tRES: %s\n",
+                             expected_err, bpf_vlog);
                        goto fail_log;
                }
        }