Create a BTF with endianness different from host, make a distilled base/split BTF pair from it, dump as raw bytes, import again and verify that endianness is preserved. Signed-off-by: Eduard Zingerman <eddyz87@xxxxxxxxx> --- .../selftests/bpf/prog_tests/btf_distill.c | 73 +++++++++++++++++++ 1 file changed, 73 insertions(+) diff --git a/tools/testing/selftests/bpf/prog_tests/btf_distill.c b/tools/testing/selftests/bpf/prog_tests/btf_distill.c index bfbe795823a2..810b2e434562 100644 --- a/tools/testing/selftests/bpf/prog_tests/btf_distill.c +++ b/tools/testing/selftests/bpf/prog_tests/btf_distill.c @@ -535,6 +535,77 @@ static void test_distilled_base_vmlinux(void) btf__free(vmlinux_btf); } +static bool is_host_big_endian(void) +{ + return htons(0x1234) == 0x1234; +} + +/* Split and new base BTFs should inherit endianness from source BTF. */ +static void test_distilled_endianness(void) +{ + struct btf *base = NULL, *split = NULL, *new_base = NULL, *new_split = NULL; + struct btf *new_base1 = NULL, *new_split1 = NULL; + enum btf_endianness inverse_endianness; + const void *raw_data; + __u32 size; + + printf("is_host_big_endian? %d\n", is_host_big_endian()); + inverse_endianness = is_host_big_endian() ? BTF_LITTLE_ENDIAN : BTF_BIG_ENDIAN; + base = btf__new_empty(); + btf__set_endianness(base, inverse_endianness); + if (!ASSERT_OK_PTR(base, "empty_main_btf")) + return; + btf__add_int(base, "int", 4, BTF_INT_SIGNED); /* [1] int */ + VALIDATE_RAW_BTF( + base, + "[1] INT 'int' size=4 bits_offset=0 nr_bits=32 encoding=SIGNED"); + split = btf__new_empty_split(base); + if (!ASSERT_OK_PTR(split, "empty_split_btf")) + goto cleanup; + btf__add_ptr(split, 1); + VALIDATE_RAW_BTF( + split, + "[1] INT 'int' size=4 bits_offset=0 nr_bits=32 encoding=SIGNED", + "[2] PTR '(anon)' type_id=1"); + if (!ASSERT_EQ(0, btf__distill_base(split, &new_base, &new_split), + "distilled_base") || + !ASSERT_OK_PTR(new_base, "distilled_base") || + !ASSERT_OK_PTR(new_split, "distilled_split") || + !ASSERT_EQ(2, btf__type_cnt(new_base), "distilled_base_type_cnt")) + goto cleanup; + VALIDATE_RAW_BTF( + new_split, + "[1] INT 'int' size=4 bits_offset=0 nr_bits=32 encoding=SIGNED", + "[2] PTR '(anon)' type_id=1"); + + raw_data = btf__raw_data(new_base, &size); + if (!ASSERT_OK_PTR(raw_data, "btf__raw_data #1")) + goto cleanup; + new_base1 = btf__new(raw_data, size); + if (!ASSERT_OK_PTR(new_base1, "new_base1 = btf__new()")) + goto cleanup; + raw_data = btf__raw_data(new_split, &size); + if (!ASSERT_OK_PTR(raw_data, "btf__raw_data #2")) + goto cleanup; + new_split1 = btf__new_split(raw_data, size, new_base1); + if (!ASSERT_OK_PTR(new_split1, "new_split1 = btf__new()")) + goto cleanup; + + ASSERT_EQ(btf__endianness(new_base1), inverse_endianness, "new_base1 endianness"); + ASSERT_EQ(btf__endianness(new_split1), inverse_endianness, "new_split1 endianness"); + VALIDATE_RAW_BTF( + new_split1, + "[1] INT 'int' size=4 bits_offset=0 nr_bits=32 encoding=SIGNED", + "[2] PTR '(anon)' type_id=1"); +cleanup: + btf__free(new_split1); + btf__free(new_base1); + btf__free(new_split); + btf__free(new_base); + btf__free(split); + btf__free(base); +} + void test_btf_distill(void) { if (test__start_subtest("distilled_base")) @@ -549,4 +620,6 @@ void test_btf_distill(void) test_distilled_base_multi_err2(); if (test__start_subtest("distilled_base_vmlinux")) test_distilled_base_vmlinux(); + if (test__start_subtest("distilled_endianness")) + test_distilled_endianness(); } -- 2.46.0