bpf: btf: Add BTF tests

This patch tests the BTF loading, map_create with BTF
and the changes in libbpf.

-r: Raw tests that test raw crafted BTF data
-f: Test LLVM compiled bpf prog with BTF data
-g: Test BPF_OBJ_GET_INFO_BY_FD for btf_fd
-p: Test pretty print

The tools/testing/selftests/bpf/Makefile will probe
for BTF support in llc and pahole before generating
debug info (-g) and convert them to BTF.  You can supply
the BTF supported binary through the following make variables:
LLC, BTF_PAHOLE and LLVM_OBJCOPY.

LLC: The lastest llc with -mattr=dwarfris support for the bpf target.
     It is only in the master of the llvm repo for now.
BTF_PAHOLE: The modified pahole with BTF support:
	    https://github.com/iamkafai/pahole/tree/btf
	    To add a BTF section: "pahole -J bpf_prog.o"
LLVM_OBJCOPY: Any llvm-objcopy should do
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Alexei Starovoitov <ast@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

tools/testing/selftests/bpf/Makefile

@@ -24,14 +24,15 @@ urandom_read: urandom_read.c
 # Order correspond to 'make run_tests' order
 TEST_GEN_PROGS = test_verifier test_tag test_maps test_lru_map test_lpm_map test_progs \
 	test_align test_verifier_log test_dev_cgroup test_tcpbpf_user \
-	test_sock test_sock_addr
+	test_sock test_sock_addr test_btf
 
 TEST_GEN_FILES = test_pkt_access.o test_xdp.o test_l4lb.o test_tcp_estats.o test_obj_id.o \
 	test_pkt_md_access.o test_xdp_redirect.o test_xdp_meta.o sockmap_parse_prog.o     \
 	sockmap_verdict_prog.o dev_cgroup.o sample_ret0.o test_tracepoint.o \
 	test_l4lb_noinline.o test_xdp_noinline.o test_stacktrace_map.o \
 	sample_map_ret0.o test_tcpbpf_kern.o test_stacktrace_build_id.o \
-	sockmap_tcp_msg_prog.o connect4_prog.o connect6_prog.o test_adjust_tail.o
+	sockmap_tcp_msg_prog.o connect4_prog.o connect6_prog.o test_adjust_tail.o \
+	test_btf_haskv.o test_btf_nokv.o
 
 # Order correspond to 'make run_tests' order
 TEST_PROGS := test_kmod.sh \
@@ -66,6 +67,8 @@ $(BPFOBJ): force
 
 CLANG ?= clang
 LLC   ?= llc
+LLVM_OBJCOPY ?= llvm-objcopy
+BTF_PAHOLE ?= pahole
 
 PROBE := $(shell $(LLC) -march=bpf -mcpu=probe -filetype=null /dev/null 2>&1)
 
@@ -83,9 +86,26 @@ CLANG_FLAGS = -I. -I./include/uapi -I../../../include/uapi \
 $(OUTPUT)/test_l4lb_noinline.o: CLANG_FLAGS += -fno-inline
 $(OUTPUT)/test_xdp_noinline.o: CLANG_FLAGS += -fno-inline
 
+BTF_LLC_PROBE := $(shell $(LLC) -march=bpf -mattr=help |& grep dwarfris)
+BTF_PAHOLE_PROBE := $(shell $(BTF_PAHOLE) --help |& grep BTF)
+BTF_OBJCOPY_PROBE := $(shell $(LLVM_OBJCOPY) --version |& grep LLVM)
+
+ifneq ($(BTF_LLC_PROBE),)
+ifneq ($(BTF_PAHOLE_PROBE),)
+ifneq ($(BTF_OBJCOPY_PROBE),)
+	CLANG_FLAGS += -g
+	LLC_FLAGS += -mattr=dwarfris
+	DWARF2BTF = y
+endif
+endif
+endif
+
 $(OUTPUT)/%.o: %.c
 	$(CLANG) $(CLANG_FLAGS) \
 		 -O2 -target bpf -emit-llvm -c $< -o - |      \
-	$(LLC) -march=bpf -mcpu=$(CPU) -filetype=obj -o $@
+	$(LLC) -march=bpf -mcpu=$(CPU) $(LLC_FLAGS) -filetype=obj -o $@
+ifeq ($(DWARF2BTF),y)
+	$(BTF_PAHOLE) -J $@
+endif
 
 EXTRA_CLEAN := $(TEST_CUSTOM_PROGS)

tools/testing/selftests/bpf/test_btf.c

+/* SPDX-License-Identifier: GPL-2.0 */
+/* Copyright (c) 2018 Facebook */
+
+#include <linux/bpf.h>
+#include <linux/btf.h>
+#include <linux/err.h>
+#include <bpf/bpf.h>
+#include <sys/resource.h>
+#include <libelf.h>
+#include <gelf.h>
+#include <string.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <stdarg.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <bpf/libbpf.h>
+#include <bpf/btf.h>
+
+#include "bpf_rlimit.h"
+
+#define min(a, b) ((a) < (b) ? (a) : (b))
+#define __printf(a, b)	__attribute__((format(printf, a, b)))
+
+__printf(1, 2)
+static int __base_pr(const char *format, ...)
+{
+	va_list args;
+	int err;
+
+	va_start(args, format);
+	err = vfprintf(stderr, format, args);
+	va_end(args);
+	return err;
+}
+
+#define BTF_INFO_ENC(kind, root, vlen)			\
+	((!!(root) << 31) | ((kind) << 24) | ((vlen) & BTF_MAX_VLEN))
+
+#define BTF_TYPE_ENC(name, info, size_or_type)	\
+	(name), (info), (size_or_type)
+
+#define BTF_INT_ENC(encoding, bits_offset, nr_bits)	\
+	((encoding) << 24 | (bits_offset) << 16 | (nr_bits))
+#define BTF_TYPE_INT_ENC(name, encoding, bits_offset, bits, sz)	\
+	BTF_TYPE_ENC(name, BTF_INFO_ENC(BTF_KIND_INT, 0, 0), sz),	\
+	BTF_INT_ENC(encoding, bits_offset, bits)
+
+#define BTF_ARRAY_ENC(type, index_type, nr_elems)	\
+	(type), (index_type), (nr_elems)
+#define BTF_TYPE_ARRAY_ENC(type, index_type, nr_elems) \
+	BTF_TYPE_ENC(0, BTF_INFO_ENC(BTF_KIND_ARRAY, 0, 0), 0), \
+	BTF_ARRAY_ENC(type, index_type, nr_elems)
+
+#define BTF_MEMBER_ENC(name, type, bits_offset)	\
+	(name), (type), (bits_offset)
+#define BTF_ENUM_ENC(name, val) (name), (val)
+
+#define BTF_TYPEDEF_ENC(name, type) \
+	BTF_TYPE_ENC(name, BTF_INFO_ENC(BTF_KIND_TYPEDEF, 0, 0), type)
+
+#define BTF_PTR_ENC(name, type) \
+	BTF_TYPE_ENC(name, BTF_INFO_ENC(BTF_KIND_PTR, 0, 0), type)
+
+#define BTF_END_RAW 0xdeadbeef
+#define NAME_TBD 0xdeadb33f
+
+#define MAX_NR_RAW_TYPES 1024
+#define BTF_LOG_BUF_SIZE 65535
+
+#ifndef ARRAY_SIZE
+# define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
+#endif
+
+static struct args {
+	unsigned int raw_test_num;
+	unsigned int file_test_num;
+	unsigned int get_info_test_num;
+	bool raw_test;
+	bool file_test;
+	bool get_info_test;
+	bool pprint_test;
+	bool always_log;
+} args;
+
+static char btf_log_buf[BTF_LOG_BUF_SIZE];
+
+static struct btf_header hdr_tmpl = {
+	.magic = BTF_MAGIC,
+	.version = BTF_VERSION,
+};
+
+struct btf_raw_test {
+	const char *descr;
+	const char *str_sec;
+	const char *map_name;
+	__u32 raw_types[MAX_NR_RAW_TYPES];
+	__u32 str_sec_size;
+	enum bpf_map_type map_type;
+	__u32 key_size;
+	__u32 value_size;
+	__u32 key_id;
+	__u32 value_id;
+	__u32 max_entries;
+	bool btf_load_err;
+	bool map_create_err;
+	int type_off_delta;
+	int str_off_delta;
+	int str_len_delta;
+};
+
+static struct btf_raw_test raw_tests[] = {
+/* enum E {
+ *     E0,
+ *     E1,
+ * };
+ *
+ * struct A {
+ *	int m;
+ *	unsigned long long n;
+ *	char o;
+ *	[3 bytes hole]
+ *	int p[8];
+ *	int q[4][8];
+ *	enum E r;
+ * };
+ */
+{
+	.descr = "struct test #1",
+	.raw_types = {
+		/* int */
+		BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4),	/* [1] */
+		/* unsigned long long */
+		BTF_TYPE_INT_ENC(0, 0, 0, 64, 8),		/* [2] */
+		/* char */
+		BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 8, 1),	/* [3] */
+		/* int[8] */
+		BTF_TYPE_ARRAY_ENC(1, 1, 8),			/* [4] */
+		/* struct A { */				/* [5] */
+		BTF_TYPE_ENC(NAME_TBD, BTF_INFO_ENC(BTF_KIND_STRUCT, 0, 6), 180),
+		BTF_MEMBER_ENC(NAME_TBD, 1, 0),	/* int m;		*/
+		BTF_MEMBER_ENC(NAME_TBD, 2, 32),/* unsigned long long n;*/
+		BTF_MEMBER_ENC(NAME_TBD, 3, 96),/* char o;		*/
+		BTF_MEMBER_ENC(NAME_TBD, 4, 128),/* int p[8]		*/
+		BTF_MEMBER_ENC(NAME_TBD, 6, 384),/* int q[4][8]		*/
+		BTF_MEMBER_ENC(NAME_TBD, 7, 1408), /* enum E r		*/
+		/* } */
+		/* int[4][8] */
+		BTF_TYPE_ARRAY_ENC(4, 1, 4),			/* [6] */
+		BTF_TYPE_ENC(NAME_TBD, BTF_INFO_ENC(BTF_KIND_ENUM, 0, 2), sizeof(int)),
+		BTF_ENUM_ENC(NAME_TBD, 0),
+		BTF_ENUM_ENC(NAME_TBD, 1),
+		BTF_END_RAW,
+	},
+	.str_sec = "\0A\0m\0n\0o\0p\0q\0r\0E\0E0\0E1",
+	.str_sec_size = sizeof("\0A\0m\0n\0o\0p\0q\0r\0E\0E0\0E1"),
+	.map_type = BPF_MAP_TYPE_ARRAY,
+	.map_name = "struct_test1_map",
+	.key_size = sizeof(int),
+	.value_size = 180,
+	.key_id = 1,
+	.value_id = 5,
+	.max_entries = 4,
+},
+
+/* typedef struct b Struct_B;
+ *
+ * struct A {
+ *     int m;
+ *     struct b n[4];
+ *     const Struct_B o[4];
+ * };
+ *
+ * struct B {
+ *     int m;
+ *     int n;
+ * };
+ */
+{
+	.descr = "struct test #2",
+	.raw_types = {
+		/* int */					/* [1] */
+		BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4),
+		/* struct b [4] */				/* [2] */
+		BTF_TYPE_ARRAY_ENC(4, 1, 4),
+
+		/* struct A { */				/* [3] */
+		BTF_TYPE_ENC(NAME_TBD, BTF_INFO_ENC(BTF_KIND_STRUCT, 0, 3), 68),
+		BTF_MEMBER_ENC(NAME_TBD, 1, 0),	/* int m;		*/
+		BTF_MEMBER_ENC(NAME_TBD, 2, 32),/* struct B n[4]	*/
+		BTF_MEMBER_ENC(NAME_TBD, 8, 288),/* const Struct_B o[4];*/
+		/* } */
+
+		/* struct B { */				/* [4] */
+		BTF_TYPE_ENC(NAME_TBD, BTF_INFO_ENC(BTF_KIND_STRUCT, 0, 2), 8),
+		BTF_MEMBER_ENC(NAME_TBD, 1, 0),	/* int m; */
+		BTF_MEMBER_ENC(NAME_TBD, 1, 32),/* int n; */
+		/* } */
+
+		/* const int */					/* [5] */
+		BTF_TYPE_ENC(0, BTF_INFO_ENC(BTF_KIND_CONST, 0, 0), 1),
+		/* typedef struct b Struct_B */	/* [6] */
+		BTF_TYPE_ENC(NAME_TBD, BTF_INFO_ENC(BTF_KIND_TYPEDEF, 0, 0), 4),
+		/* const Struct_B */				/* [7] */
+		BTF_TYPE_ENC(0, BTF_INFO_ENC(BTF_KIND_CONST, 0, 0), 6),
+		/* const Struct_B [4] */			/* [8] */
+		BTF_TYPE_ARRAY_ENC(7, 1, 4),
+		BTF_END_RAW,
+	},
+	.str_sec = "\0A\0m\0n\0o\0B\0m\0n\0Struct_B",
+	.str_sec_size = sizeof("\0A\0m\0n\0o\0B\0m\0n\0Struct_B"),
+	.map_type = BPF_MAP_TYPE_ARRAY,
+	.map_name = "struct_test2_map",
+	.key_size = sizeof(int),
+	.value_size = 68,
+	.key_id = 1,
+	.value_id = 3,
+	.max_entries = 4,
+},
+
+/* Test member exceeds the size of struct.
+ *
+ * struct A {
+ *     int m;
+ *     int n;
+ * };
+ */
+{
+	.descr = "size check test #1",
+	.raw_types = {
+		/* int */					/* [1] */
+		BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4),
+		/* struct A { */				/* [2] */
+		BTF_TYPE_ENC(NAME_TBD, BTF_INFO_ENC(BTF_KIND_STRUCT, 0, 2), sizeof(int) * 2 -  1),
+		BTF_MEMBER_ENC(NAME_TBD, 1, 0),	/* int m; */
+		BTF_MEMBER_ENC(NAME_TBD, 2, 32),/* int n; */
+		/* } */
+		BTF_END_RAW,
+	},
+	.str_sec = "\0A\0m\0n",
+	.str_sec_size = sizeof("\0A\0m\0n"),
+	.map_type = BPF_MAP_TYPE_ARRAY,
+	.map_name = "size_check1_map",
+	.key_size = sizeof(int),
+	.value_size = 1,
+	.key_id = 1,
+	.value_id = 2,
+	.max_entries = 4,
+	.btf_load_err = true,
+},
+
+/* Test member exeeds the size of struct
+ *
+ * struct A {
+ *     int m;
+ *     int n[2];
+ * };
+ */
+{
+	.descr = "size check test #2",
+	.raw_types = {
+		/* int */					/* [1] */
+		BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, sizeof(int)),
+		/* int[2] */					/* [2] */
+		BTF_TYPE_ARRAY_ENC(1, 1, 2),
+		/* struct A { */				/* [3] */
+		BTF_TYPE_ENC(NAME_TBD, BTF_INFO_ENC(BTF_KIND_STRUCT, 0, 2), sizeof(int) * 3 - 1),
+		BTF_MEMBER_ENC(NAME_TBD, 1, 0),	/* int m; */
+		BTF_MEMBER_ENC(NAME_TBD, 2, 32),/* int n[2]; */
+		/* } */
+		BTF_END_RAW,
+	},
+	.str_sec = "\0A\0m\0n",
+	.str_sec_size = sizeof("\0A\0m\0n"),
+	.map_type = BPF_MAP_TYPE_ARRAY,
+	.map_name = "size_check2_map",
+	.key_size = sizeof(int),
+	.value_size = 1,
+	.key_id = 1,
+	.value_id = 3,
+	.max_entries = 4,
+	.btf_load_err = true,
+
+},
+
+/* Test member exeeds the size of struct
+ *
+ * struct A {
+ *     int m;
+ *     void *n;
+ * };
+ */
+{
+	.descr = "size check test #3",
+	.raw_types = {
+		/* int */					/* [1] */
+		BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, sizeof(int)),
+		/* void* */					/* [2] */
+		BTF_TYPE_ENC(0, BTF_INFO_ENC(BTF_KIND_PTR, 0, 0), 0),
+		/* struct A { */				/* [3] */
+		BTF_TYPE_ENC(NAME_TBD, BTF_INFO_ENC(BTF_KIND_STRUCT, 0, 2), sizeof(int) + sizeof(void *) - 1),
+		BTF_MEMBER_ENC(NAME_TBD, 1, 0),	/* int m; */
+		BTF_MEMBER_ENC(NAME_TBD, 2, 32),/* void *n; */
+		/* } */
+		BTF_END_RAW,
+	},
+	.str_sec = "\0A\0m\0n",
+	.str_sec_size = sizeof("\0A\0m\0n"),
+	.map_type = BPF_MAP_TYPE_ARRAY,
+	.map_name = "size_check3_map",
+	.key_size = sizeof(int),
+	.value_size = 1,
+	.key_id = 1,
+	.value_id = 3,
+	.max_entries = 4,
+	.btf_load_err = true,
+},
+
+/* Test member exceeds the size of struct
+ *
+ * enum E {
+ *     E0,
+ *     E1,
+ * };
+ *
+ * struct A {
+ *     int m;
+ *     enum E n;
+ * };
+ */
+{
+	.descr = "size check test #4",
+	.raw_types = {
+		/* int */			/* [1] */
+		BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, sizeof(int)),
+		/* enum E { */			/* [2] */
+		BTF_TYPE_ENC(NAME_TBD, BTF_INFO_ENC(BTF_KIND_ENUM, 0, 2), sizeof(int)),
+		BTF_ENUM_ENC(NAME_TBD, 0),
+		BTF_ENUM_ENC(NAME_TBD, 1),
+		/* } */
+		/* struct A { */		/* [3] */
+		BTF_TYPE_ENC(NAME_TBD, BTF_INFO_ENC(BTF_KIND_STRUCT, 0, 2), sizeof(int) * 2 - 1),
+		BTF_MEMBER_ENC(NAME_TBD, 1, 0),	/* int m; */
+		BTF_MEMBER_ENC(NAME_TBD, 2, 32),/* enum E n; */
+		/* } */
+		BTF_END_RAW,
+	},
+	.str_sec = "\0E\0E0\0E1\0A\0m\0n",
+	.str_sec_size = sizeof("\0E\0E0\0E1\0A\0m\0n"),
+	.map_type = BPF_MAP_TYPE_ARRAY,
+	.map_name = "size_check4_map",
+	.key_size = sizeof(int),
+	.value_size = 1,
+	.key_id = 1,
+	.value_id = 3,
+	.max_entries = 4,
+	.btf_load_err = true,
+},
+
+/* typedef const void * const_void_ptr;
+ * struct A {
+ *	const_void_ptr m;
+ * };
+ */
+{
+	.descr = "void test #1",
+	.raw_types = {
+		/* int */		/* [1] */
+		BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4),
+		/* const void */	/* [2] */
+		BTF_TYPE_ENC(0, BTF_INFO_ENC(BTF_KIND_CONST, 0, 0), 0),
+		/* const void* */	/* [3] */
+		BTF_TYPE_ENC(0, BTF_INFO_ENC(BTF_KIND_PTR, 0, 0), 2),
+		/* typedef const void * const_void_ptr */
+		BTF_TYPE_ENC(NAME_TBD, BTF_INFO_ENC(BTF_KIND_PTR, 0, 0), 3),
+		/* struct A { */	/* [4] */
+		BTF_TYPE_ENC(NAME_TBD, BTF_INFO_ENC(BTF_KIND_STRUCT, 0, 1), sizeof(void *)),
+		/* const_void_ptr m; */
+		BTF_MEMBER_ENC(NAME_TBD, 3, 0),
+		/* } */
+		BTF_END_RAW,
+	},
+	.str_sec = "\0const_void_ptr\0A\0m",
+	.str_sec_size = sizeof("\0const_void_ptr\0A\0m"),
+	.map_type = BPF_MAP_TYPE_ARRAY,
+	.map_name = "void_test1_map",
+	.key_size = sizeof(int),
+	.value_size = sizeof(void *),
+	.key_id = 1,
+	.value_id = 4,
+	.max_entries = 4,
+},
+
+/* struct A {
+ *     const void m;
+ * };
+ */
+{
+	.descr = "void test #2",
+	.raw_types = {
+		/* int */		/* [1] */
+		BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4),
+		/* const void */	/* [2] */
+		BTF_TYPE_ENC(0, BTF_INFO_ENC(BTF_KIND_CONST, 0, 0), 0),
+		/* struct A { */	/* [3] */
+		BTF_TYPE_ENC(NAME_TBD, BTF_INFO_ENC(BTF_KIND_STRUCT, 0, 1), 8),
+		/* const void m; */
+		BTF_MEMBER_ENC(NAME_TBD, 2, 0),
+		/* } */
+		BTF_END_RAW,
+	},
+	.str_sec = "\0A\0m",
+	.str_sec_size = sizeof("\0A\0m"),
+	.map_type = BPF_MAP_TYPE_ARRAY,
+	.map_name = "void_test2_map",
+	.key_size = sizeof(int),
+	.value_size = sizeof(void *),
+	.key_id = 1,
+	.value_id = 3,
+	.max_entries = 4,
+	.btf_load_err = true,
+},
+
+/* typedef const void * const_void_ptr;
+ * const_void_ptr[4]
+ */
+{
+	.descr = "void test #3",
+	.raw_types = {
+		/* int */		/* [1] */
+		BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4),
+		/* const void */	/* [2] */
+		BTF_TYPE_ENC(0, BTF_INFO_ENC(BTF_KIND_CONST, 0, 0), 0),
+		/* const void* */	/* [3] */
+		BTF_TYPE_ENC(0, BTF_INFO_ENC(BTF_KIND_PTR, 0, 0), 2),
+		/* typedef const void * const_void_ptr */
+		BTF_TYPE_ENC(NAME_TBD, BTF_INFO_ENC(BTF_KIND_PTR, 0, 0), 3),
+		/* const_void_ptr[4] */	/* [4] */
+		BTF_TYPE_ARRAY_ENC(3, 1, 4),
+		BTF_END_RAW,
+	},
+	.str_sec = "\0const_void_ptr",
+	.str_sec_size = sizeof("\0const_void_ptr"),
+	.map_type = BPF_MAP_TYPE_ARRAY,
+	.map_name = "void_test3_map",
+	.key_size = sizeof(int),
+	.value_size = sizeof(void *) * 4,
+	.key_id = 1,
+	.value_id = 4,
+	.max_entries = 4,
+},
+
+/* const void[4]  */
+{
+	.descr = "void test #4",
+	.raw_types = {
+		/* int */		/* [1] */
+		BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4),
+		/* const void */	/* [2] */
+		BTF_TYPE_ENC(0, BTF_INFO_ENC(BTF_KIND_CONST, 0, 0), 0),
+		/* const void[4] */	/* [3] */
+		BTF_TYPE_ARRAY_ENC(2, 1, 4),
+		BTF_END_RAW,
+	},
+	.str_sec = "\0A\0m",
+	.str_sec_size = sizeof("\0A\0m"),
+	.map_type = BPF_MAP_TYPE_ARRAY,
+	.map_name = "void_test4_map",
+	.key_size = sizeof(int),
+	.value_size = sizeof(void *) * 4,
+	.key_id = 1,
+	.value_id = 3,
+	.max_entries = 4,
+	.btf_load_err = true,
+},
+
+/* Array_A  <------------------+
+ *     elem_type == Array_B    |
+ *                    |        |
+ *                    |        |
+ * Array_B  <-------- +        |
+ *      elem_type == Array A --+
+ */
+{
+	.descr = "loop test #1",
+	.raw_types = {
+		/* int */			/* [1] */
+		BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4),
+		/* Array_A */			/* [2] */
+		BTF_TYPE_ARRAY_ENC(3, 1, 8),
+		/* Array_B */			/* [3] */
+		BTF_TYPE_ARRAY_ENC(2, 1, 8),
+		BTF_END_RAW,
+	},
+	.str_sec = "",
+	.str_sec_size = sizeof(""),
+	.map_type = BPF_MAP_TYPE_ARRAY,
+	.map_name = "loop_test1_map",
+	.key_size = sizeof(int),
+	.value_size = sizeof(sizeof(int) * 8),
+	.key_id = 1,
+	.value_id = 2,
+	.max_entries = 4,
+	.btf_load_err = true,
+},
+
+/* typedef is _before_ the BTF type of Array_A and Array_B
+ *
+ * typedef Array_B int_array;
+ *
+ * Array_A  <------------------+
+ *     elem_type == int_array  |
+ *                    |        |
+ *                    |        |
+ * Array_B  <-------- +        |
+ *      elem_type == Array_A --+
+ */
+{
+	.descr = "loop test #2",
+	.raw_types = {
+		/* int */
+		BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4),	/* [1] */
+		/* typedef Array_B int_array */
+		BTF_TYPEDEF_ENC(1, 4),				/* [2] */
+		/* Array_A */
+		BTF_TYPE_ARRAY_ENC(2, 1, 8),			/* [3] */
+		/* Array_B */
+		BTF_TYPE_ARRAY_ENC(3, 1, 8),			/* [4] */
+
+		BTF_END_RAW,
+	},
+	.str_sec = "\0int_array\0",
+	.str_sec_size = sizeof("\0int_array"),
+	.map_type = BPF_MAP_TYPE_ARRAY,
+	.map_name = "loop_test2_map",
+	.key_size = sizeof(int),
+	.value_size = sizeof(sizeof(int) * 8),
+	.key_id = 1,
+	.value_id = 2,
+	.max_entries = 4,
+	.btf_load_err = true,
+},
+
+/* Array_A  <------------------+
+ *     elem_type == Array_B    |
+ *                    |        |
+ *                    |        |
+ * Array_B  <-------- +        |
+ *      elem_type == Array_A --+
+ */
+{
+	.descr = "loop test #3",
+	.raw_types = {
+		/* int */				/* [1] */
+		BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4),
+		/* Array_A */				/* [2] */
+		BTF_TYPE_ARRAY_ENC(3, 1, 8),
+		/* Array_B */				/* [3] */
+		BTF_TYPE_ARRAY_ENC(2, 1, 8),
+
+		BTF_END_RAW,
+	},
+	.str_sec = "",
+	.str_sec_size = sizeof(""),
+	.map_type = BPF_MAP_TYPE_ARRAY,
+	.map_name = "loop_test3_map",
+	.key_size = sizeof(int),
+	.value_size = sizeof(sizeof(int) * 8),
+	.key_id = 1,
+	.value_id = 2,
+	.max_entries = 4,
+	.btf_load_err = true,
+},
+
+/* typedef is _between_ the BTF type of Array_A and Array_B
+ *
+ * typedef Array_B int_array;
+ *
+ * Array_A  <------------------+
+ *     elem_type == int_array  |
+ *                    |        |
+ *                    |        |
+ * Array_B  <-------- +        |
+ *      elem_type == Array_A --+
+ */
+{
+	.descr = "loop test #4",
+	.raw_types = {
+		/* int */				/* [1] */
+		BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4),
+		/* Array_A */				/* [2] */
+		BTF_TYPE_ARRAY_ENC(3, 1, 8),
+		/* typedef Array_B int_array */		/* [3] */
+		BTF_TYPEDEF_ENC(NAME_TBD, 4),
+		/* Array_B */				/* [4] */
+		BTF_TYPE_ARRAY_ENC(2, 1, 8),
+		BTF_END_RAW,
+	},
+	.str_sec = "\0int_array\0",
+	.str_sec_size = sizeof("\0int_array"),
+	.map_type = BPF_MAP_TYPE_ARRAY,
+	.map_name = "loop_test4_map",
+	.key_size = sizeof(int),
+	.value_size = sizeof(sizeof(int) * 8),
+	.key_id = 1,
+	.value_id = 2,
+	.max_entries = 4,
+	.btf_load_err = true,
+},
+
+/* typedef struct B Struct_B
+ *
+ * struct A {
+ *     int x;
+ *     Struct_B y;
+ * };
+ *
+ * struct B {
+ *     int x;
+ *     struct A y;
+ * };
+ */
+{
+	.descr = "loop test #5",
+	.raw_types = {
+		/* int */
+		BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4),	/* [1] */
+		/* struct A */					/* [2] */
+		BTF_TYPE_ENC(NAME_TBD, BTF_INFO_ENC(BTF_KIND_STRUCT, 0, 2), 8),
+		BTF_MEMBER_ENC(NAME_TBD, 1, 0),	/* int x;	*/
+		BTF_MEMBER_ENC(NAME_TBD, 3, 32),/* Struct_B y;	*/
+		/* typedef struct B Struct_B */
+		BTF_TYPEDEF_ENC(NAME_TBD, 4),			/* [3] */
+		/* struct B */					/* [4] */
+		BTF_TYPE_ENC(NAME_TBD, BTF_INFO_ENC(BTF_KIND_STRUCT, 0, 2), 8),
+		BTF_MEMBER_ENC(NAME_TBD, 1, 0),	/* int x;	*/
+		BTF_MEMBER_ENC(NAME_TBD, 2, 32),/* struct A y;	*/
+		BTF_END_RAW,
+	},
+	.str_sec = "\0A\0x\0y\0Struct_B\0B\0x\0y",
+	.str_sec_size = sizeof("\0A\0x\0y\0Struct_B\0B\0x\0y"),
+	.map_type = BPF_MAP_TYPE_ARRAY,
+	.map_name = "loop_test5_map",
+	.key_size = sizeof(int),
+	.value_size = 8,
+	.key_id = 1,
+	.value_id = 2,
+	.max_entries = 4,
+	.btf_load_err = true,
+},
+
+/* struct A {
+ *     int x;
+ *     struct A array_a[4];
+ * };
+ */
+{
+	.descr = "loop test #6",
+	.raw_types = {
+		/* int */
+		BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4),	/* [1] */
+		BTF_TYPE_ARRAY_ENC(3, 1, 4),			/* [2] */
+		/* struct A */					/* [3] */
+		BTF_TYPE_ENC(NAME_TBD, BTF_INFO_ENC(BTF_KIND_STRUCT, 0, 2), 8),
+		BTF_MEMBER_ENC(NAME_TBD, 1, 0),	/* int x;		*/
+		BTF_MEMBER_ENC(NAME_TBD, 2, 32),/* struct A array_a[4];	*/
+		BTF_END_RAW,
+	},
+	.str_sec = "\0A\0x\0y",
+	.str_sec_size = sizeof("\0A\0x\0y"),
+	.map_type = BPF_MAP_TYPE_ARRAY,
+	.map_name = "loop_test6_map",
+	.key_size = sizeof(int),
+	.value_size = 8,
+	.key_id = 1,
+	.value_id = 2,
+	.max_entries = 4,
+	.btf_load_err = true,
+},
+
+{
+	.descr = "loop test #7",
+	.raw_types = {
+		/* int */				/* [1] */
+		BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4),
+		/* struct A { */			/* [2] */
+		BTF_TYPE_ENC(NAME_TBD, BTF_INFO_ENC(BTF_KIND_STRUCT, 0, 1), sizeof(void *)),
+		/*     const void *m;	*/
+		BTF_MEMBER_ENC(NAME_TBD, 3, 0),
+		/* CONST type_id=3	*/		/* [3] */
+		BTF_TYPE_ENC(0, BTF_INFO_ENC(BTF_KIND_CONST, 0, 0), 4),
+		/* PTR type_id=2	*/		/* [4] */
+		BTF_TYPE_ENC(0, BTF_INFO_ENC(BTF_KIND_PTR, 0, 0), 3),
+		BTF_END_RAW,
+	},
+	.str_sec = "\0A\0m",
+	.str_sec_size = sizeof("\0A\0m"),
+	.map_type = BPF_MAP_TYPE_ARRAY,
+	.map_name = "loop_test7_map",
+	.key_size = sizeof(int),
+	.value_size = sizeof(void *),
+	.key_id = 1,
+	.value_id = 2,
+	.max_entries = 4,
+	.btf_load_err = true,
+},
+
+{
+	.descr = "loop test #8",
+	.raw_types = {
+		/* int */				/* [1] */
+		BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4),
+		/* struct A { */			/* [2] */
+		BTF_TYPE_ENC(NAME_TBD, BTF_INFO_ENC(BTF_KIND_STRUCT, 0, 1), sizeof(void *)),
+		/*     const void *m;	*/
+		BTF_MEMBER_ENC(NAME_TBD, 4, 0),
+		/* struct B { */			/* [3] */
+		BTF_TYPE_ENC(NAME_TBD, BTF_INFO_ENC(BTF_KIND_STRUCT, 0, 1), sizeof(void *)),
+		/*     const void *n;	*/
+		BTF_MEMBER_ENC(NAME_TBD, 6, 0),
+		/* CONST type_id=5	*/		/* [4] */
+		BTF_TYPE_ENC(0, BTF_INFO_ENC(BTF_KIND_CONST, 0, 0), 5),
+		/* PTR type_id=6	*/		/* [5] */
+		BTF_TYPE_ENC(0, BTF_INFO_ENC(BTF_KIND_PTR, 0, 0), 6),
+		/* CONST type_id=7	*/		/* [6] */
+		BTF_TYPE_ENC(0, BTF_INFO_ENC(BTF_KIND_CONST, 0, 0), 7),
+		/* PTR type_id=4	*/		/* [7] */
+		BTF_TYPE_ENC(0, BTF_INFO_ENC(BTF_KIND_PTR, 0, 0), 4),
+		BTF_END_RAW,
+	},
+	.str_sec = "\0A\0m\0B\0n",
+	.str_sec_size = sizeof("\0A\0m\0B\0n"),
+	.map_type = BPF_MAP_TYPE_ARRAY,
+	.map_name = "loop_test8_map",
+	.key_size = sizeof(int),
+	.value_size = sizeof(void *),
+	.key_id = 1,
+	.value_id = 2,
+	.max_entries = 4,
+	.btf_load_err = true,
+},
+
+{
+	.descr = "type_off == str_off",
+	.raw_types = {
+		/* int */				/* [1] */
+		BTF_TYPE_INT_ENC(NAME_TBD, BTF_INT_SIGNED, 0, 32, 4),
+		BTF_END_RAW,
+	},
+	.str_sec = "\0int",
+	.str_sec_size = sizeof("\0int"),
+	.map_type = BPF_MAP_TYPE_ARRAY,
+	.map_name = "hdr_test_map",
+	.key_size = sizeof(int),
+	.value_size = sizeof(int),
+	.key_id = 1,
+	.value_id = 1,
+	.max_entries = 4,
+	.btf_load_err = true,
+	.type_off_delta = sizeof(struct btf_type) + sizeof(int) + sizeof("\0int"),
+},
+
+{
+	.descr = "Unaligned type_off",
+	.raw_types = {
+		/* int */				/* [1] */
+		BTF_TYPE_INT_ENC(NAME_TBD, BTF_INT_SIGNED, 0, 32, 4),
+		BTF_END_RAW,
+	},
+	.str_sec = "\0int",
+	.str_sec_size = sizeof("\0int"),
+	.map_type = BPF_MAP_TYPE_ARRAY,
+	.map_name = "hdr_test_map",
+	.key_size = sizeof(int),
+	.value_size = sizeof(int),
+	.key_id = 1,
+	.value_id = 1,
+	.max_entries = 4,
+	.btf_load_err = true,
+	.type_off_delta = 1,
+},
+
+{
+	.descr = "str_off beyonds btf size",
+	.raw_types = {
+		/* int */				/* [1] */
+		BTF_TYPE_INT_ENC(NAME_TBD, BTF_INT_SIGNED, 0, 32, 4),
+		BTF_END_RAW,
+	},
+	.str_sec = "\0int",
+	.str_sec_size = sizeof("\0int"),
+	.map_type = BPF_MAP_TYPE_ARRAY,
+	.map_name = "hdr_test_map",
+	.key_size = sizeof(int),
+	.value_size = sizeof(int),
+	.key_id = 1,
+	.value_id = 1,
+	.max_entries = 4,
+	.btf_load_err = true,
+	.str_off_delta = sizeof("\0int") + 1,
+},
+
+{
+	.descr = "str_len beyonds btf size",
+	.raw_types = {
+		/* int */				/* [1] */
+		BTF_TYPE_INT_ENC(NAME_TBD, BTF_INT_SIGNED, 0, 32, 4),
+		BTF_END_RAW,
+	},
+	.str_sec = "\0int",
+	.str_sec_size = sizeof("\0int"),
+	.map_type = BPF_MAP_TYPE_ARRAY,
+	.map_name = "hdr_test_map",
+	.key_size = sizeof(int),
+	.value_size = sizeof(int),
+	.key_id = 1,
+	.value_id = 1,
+	.max_entries = 4,
+	.btf_load_err = true,
+	.str_len_delta = 1,
+},
+
+{
+	.descr = "String section does not end with null",
+	.raw_types = {
+		/* int */				/* [1] */
+		BTF_TYPE_INT_ENC(NAME_TBD, BTF_INT_SIGNED, 0, 32, 4),
+		BTF_END_RAW,
+	},
+	.str_sec = "\0int",
+	.str_sec_size = sizeof("\0int"),
+	.map_type = BPF_MAP_TYPE_ARRAY,
+	.map_name = "hdr_test_map",
+	.key_size = sizeof(int),
+	.value_size = sizeof(int),
+	.key_id = 1,
+	.value_id = 1,
+	.max_entries = 4,
+	.btf_load_err = true,
+	.str_len_delta = -1,
+},
+
+{
+	.descr = "Empty string section",
+	.raw_types = {
+		/* int */				/* [1] */
+		BTF_TYPE_INT_ENC(NAME_TBD, BTF_INT_SIGNED, 0, 32, 4),
+		BTF_END_RAW,
+	},
+	.str_sec = "\0int",
+	.str_sec_size = sizeof("\0int"),
+	.map_type = BPF_MAP_TYPE_ARRAY,
+	.map_name = "hdr_test_map",
+	.key_size = sizeof(int),
+	.value_size = sizeof(int),
+	.key_id = 1,
+	.value_id = 1,
+	.max_entries = 4,
+	.btf_load_err = true,
+	.str_len_delta = 0 - (int)sizeof("\0int"),
+},
+
+}; /* struct btf_raw_test raw_tests[] */
+
+static const char *get_next_str(const char *start, const char *end)
+{
+	return start < end - 1 ? start + 1 : NULL;
+}
+
+static int get_type_sec_size(const __u32 *raw_types)
+{
+	int i;
+
+	for (i = MAX_NR_RAW_TYPES - 1;
+	     i >= 0 && raw_types[i] != BTF_END_RAW;
+	     i--)
+		;
+
+	return i < 0 ? i : i * sizeof(raw_types[0]);
+}
+
+static void *btf_raw_create(const struct btf_header *hdr,
+			    const __u32 *raw_types,
+			    const char *str,
+			    unsigned int str_sec_size,
+			    unsigned int *btf_size)
+{
+	const char *next_str = str, *end_str = str + str_sec_size;
+	unsigned int size_needed, offset;
+	struct btf_header *ret_hdr;
+	int i, type_sec_size;
+	uint32_t *ret_types;
+	void *raw_btf;
+
+	type_sec_size = get_type_sec_size(raw_types);
+	if (type_sec_size < 0) {
+		fprintf(stderr, "Cannot get nr_raw_types\n");
+		return NULL;
+	}
+
+	size_needed = sizeof(*hdr) + type_sec_size + str_sec_size;
+	raw_btf = malloc(size_needed);
+	if (!raw_btf) {
+		fprintf(stderr, "Cannot allocate memory for raw_btf\n");
+		return NULL;
+	}
+
+	/* Copy header */
+	memcpy(raw_btf, hdr, sizeof(*hdr));
+	offset = sizeof(*hdr);
+
+	/* Copy type section */
+	ret_types = raw_btf + offset;
+	for (i = 0; i < type_sec_size / sizeof(raw_types[0]); i++) {
+		if (raw_types[i] == NAME_TBD) {
+			next_str = get_next_str(next_str, end_str);
+			if (!next_str) {
+				fprintf(stderr, "Error in getting next_str\n");
+				free(raw_btf);
+				return NULL;
+			}
+			ret_types[i] = next_str - str;
+			next_str += strlen(next_str);
+		} else {
+			ret_types[i] = raw_types[i];
+		}
+	}
+	offset += type_sec_size;
+
+	/* Copy string section */
+	memcpy(raw_btf + offset, str, str_sec_size);
+
+	ret_hdr = (struct btf_header *)raw_btf;
+	ret_hdr->str_off = type_sec_size;
+	ret_hdr->str_len = str_sec_size;
+
+	*btf_size = size_needed;
+
+	return raw_btf;
+}
+
+static int do_test_raw(unsigned int test_num)
+{
+	struct btf_raw_test *test = &raw_tests[test_num - 1];
+	struct bpf_create_map_attr create_attr = {};
+	int map_fd = -1, btf_fd = -1;
+	unsigned int raw_btf_size;
+	struct btf_header *hdr;
+	void *raw_btf;
+	int err;
+
+	fprintf(stderr, "BTF raw test[%u] (%s): ", test_num, test->descr);
+	raw_btf = btf_raw_create(&hdr_tmpl,
+				 test->raw_types,
+				 test->str_sec,
+				 test->str_sec_size,
+				 &raw_btf_size);
+
+	if (!raw_btf)
+		return -1;
+
+	hdr = raw_btf;
+
+	hdr->type_off = (int)hdr->type_off + test->type_off_delta;
+	hdr->str_off = (int)hdr->str_off + test->str_off_delta;
+	hdr->str_len = (int)hdr->str_len + test->str_len_delta;
+
+	*btf_log_buf = '\0';
+	btf_fd = bpf_load_btf(raw_btf, raw_btf_size,
+			      btf_log_buf, BTF_LOG_BUF_SIZE,
+			      args.always_log);
+	free(raw_btf);
+
+	err = ((btf_fd == -1) != test->btf_load_err);
+	if (err)
+		fprintf(stderr, "btf_load_err:%d btf_fd:%d\n",
+			test->btf_load_err, btf_fd);
+
+	if (err || btf_fd == -1)
+		goto done;
+
+	create_attr.name = test->map_name;
+	create_attr.map_type = test->map_type;
+	create_attr.key_size = test->key_size;
+	create_attr.value_size = test->value_size;
+	create_attr.max_entries = test->max_entries;
+	create_attr.btf_fd = btf_fd;
+	create_attr.btf_key_id = test->key_id;
+	create_attr.btf_value_id = test->value_id;
+
+	map_fd = bpf_create_map_xattr(&create_attr);
+
+	err = ((map_fd == -1) != test->map_create_err);
+	if (err)
+		fprintf(stderr, "map_create_err:%d map_fd:%d\n",
+			test->map_create_err, map_fd);
+
+done:
+	if (!err)
+		fprintf(stderr, "OK\n");
+
+	if (*btf_log_buf && (err || args.always_log))
+		fprintf(stderr, "%s\n", btf_log_buf);
+
+	if (btf_fd != -1)
+		close(btf_fd);
+	if (map_fd != -1)
+		close(map_fd);
+
+	return err;
+}
+
+static int test_raw(void)
+{
+	unsigned int i;
+	int err = 0;
+
+	if (args.raw_test_num)
+		return do_test_raw(args.raw_test_num);
+
+	for (i = 1; i <= ARRAY_SIZE(raw_tests); i++)
+		err |= do_test_raw(i);
+
+	return err;
+}
+
+struct btf_get_info_test {
+	const char *descr;
+	const char *str_sec;
+	__u32 raw_types[MAX_NR_RAW_TYPES];
+	__u32 str_sec_size;
+	int info_size_delta;
+};
+
+const struct btf_get_info_test get_info_tests[] = {
+{
+	.descr = "== raw_btf_size+1",
+	.raw_types = {
+		/* int */				/* [1] */
+		BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4),
+		BTF_END_RAW,
+	},
+	.str_sec = "",
+	.str_sec_size = sizeof(""),
+	.info_size_delta = 1,
+},
+{
+	.descr = "== raw_btf_size-3",
+	.raw_types = {
+		/* int */				/* [1] */
+		BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4),
+		BTF_END_RAW,
+	},
+	.str_sec = "",
+	.str_sec_size = sizeof(""),
+	.info_size_delta = -3,
+},
+};
+
+static int do_test_get_info(unsigned int test_num)
+{
+	const struct btf_get_info_test *test = &get_info_tests[test_num - 1];
+	unsigned int raw_btf_size, user_btf_size, expected_nbytes;
+	uint8_t *raw_btf = NULL, *user_btf = NULL;
+	int btf_fd = -1, err;
+
+	fprintf(stderr, "BTF GET_INFO_BY_ID test[%u] (%s): ",
+		test_num, test->descr);
+
+	raw_btf = btf_raw_create(&hdr_tmpl,
+				 test->raw_types,
+				 test->str_sec,
+				 test->str_sec_size,
+				 &raw_btf_size);
+
+	if (!raw_btf)
+		return -1;
+
+	*btf_log_buf = '\0';
+
+	user_btf = malloc(raw_btf_size);
+	if (!user_btf) {
+		fprintf(stderr, "Cannot allocate memory for user_btf\n");
+		err = -1;
+		goto done;
+	}
+
+	btf_fd = bpf_load_btf(raw_btf, raw_btf_size,
+			      btf_log_buf, BTF_LOG_BUF_SIZE,
+			      args.always_log);
+	if (btf_fd == -1) {
+		fprintf(stderr, "bpf_load_btf:%s(%d)\n",
+			strerror(errno), errno);
+		err = -1;
+		goto done;
+	}
+
+	user_btf_size = (int)raw_btf_size + test->info_size_delta;
+	expected_nbytes = min(raw_btf_size, user_btf_size);
+	if (raw_btf_size > expected_nbytes)
+		memset(user_btf + expected_nbytes, 0xff,
+		       raw_btf_size - expected_nbytes);
+
+	err = bpf_obj_get_info_by_fd(btf_fd, user_btf, &user_btf_size);
+	if (err || user_btf_size != raw_btf_size ||
+	    memcmp(raw_btf, user_btf, expected_nbytes)) {
+		fprintf(stderr,
+			"err:%d(errno:%d) raw_btf_size:%u user_btf_size:%u expected_nbytes:%u memcmp:%d\n",
+			err, errno,
+			raw_btf_size, user_btf_size, expected_nbytes,
+			memcmp(raw_btf, user_btf, expected_nbytes));
+		err = -1;
+		goto done;
+	}
+
+	while (expected_nbytes < raw_btf_size) {
+		fprintf(stderr, "%u...", expected_nbytes);
+		if (user_btf[expected_nbytes++] != 0xff) {
+			fprintf(stderr, "!= 0xff\n");
+			err = -1;
+			goto done;
+		}
+	}
+
+	fprintf(stderr, "OK\n");
+
+done:
+	if (*btf_log_buf && (err || args.always_log))
+		fprintf(stderr, "%s\n", btf_log_buf);
+
+	free(raw_btf);
+	free(user_btf);
+
+	if (btf_fd != -1)
+		close(btf_fd);
+
+	return err;
+}
+
+static int test_get_info(void)
+{
+	unsigned int i;
+	int err = 0;
+
+	if (args.get_info_test_num)
+		return do_test_get_info(args.get_info_test_num);
+
+	for (i = 1; i <= ARRAY_SIZE(get_info_tests); i++)
+		err |= do_test_get_info(i);
+
+	return err;
+}
+
+struct btf_file_test {
+	const char *file;
+	bool btf_kv_notfound;
+};
+
+static struct btf_file_test file_tests[] = {
+{
+	.file = "test_btf_haskv.o",
+},
+{
+	.file = "test_btf_nokv.o",
+	.btf_kv_notfound = true,
+},
+};
+
+static int file_has_btf_elf(const char *fn)
+{
+	Elf_Scn *scn = NULL;
+	GElf_Ehdr ehdr;
+	int elf_fd;
+	Elf *elf;
+	int ret;
+
+	if (elf_version(EV_CURRENT) == EV_NONE) {
+		fprintf(stderr, "Failed to init libelf\n");
+		return -1;
+	}
+
+	elf_fd = open(fn, O_RDONLY);
+	if (elf_fd == -1) {
+		fprintf(stderr, "Cannot open file %s: %s(%d)\n",
+			fn, strerror(errno), errno);
+		return -1;
+	}
+
+	elf = elf_begin(elf_fd, ELF_C_READ, NULL);
+	if (!elf) {
+		fprintf(stderr, "Failed to read ELF from %s. %s\n", fn,
+			elf_errmsg(elf_errno()));
+		ret = -1;
+		goto done;
+	}
+
+	if (!gelf_getehdr(elf, &ehdr)) {
+		fprintf(stderr, "Failed to get EHDR from %s\n", fn);
+		ret = -1;
+		goto done;
+	}
+
+	while ((scn = elf_nextscn(elf, scn))) {
+		const char *sh_name;
+		GElf_Shdr sh;
+
+		if (gelf_getshdr(scn, &sh) != &sh) {
+			fprintf(stderr,
+				"Failed to get section header from %s\n", fn);
+			ret = -1;
+			goto done;
+		}
+
+		sh_name = elf_strptr(elf, ehdr.e_shstrndx, sh.sh_name);
+		if (!strcmp(sh_name, BTF_ELF_SEC)) {
+			ret = 1;
+			goto done;
+		}
+	}
+
+	ret = 0;
+
+done:
+	close(elf_fd);
+	elf_end(elf);
+	return ret;
+}
+
+static int do_test_file(unsigned int test_num)
+{
+	const struct btf_file_test *test = &file_tests[test_num - 1];
+	struct bpf_object *obj = NULL;
+	struct bpf_program *prog;
+	struct bpf_map *map;
+	int err;
+
+	fprintf(stderr, "BTF libbpf test[%u] (%s): ", test_num,
+		test->file);
+
+	err = file_has_btf_elf(test->file);
+	if (err == -1)
+		return err;
+
+	if (err == 0) {
+		fprintf(stderr, "SKIP. No ELF %s found\n", BTF_ELF_SEC);
+		return 0;
+	}
+
+	obj = bpf_object__open(test->file);
+	if (IS_ERR(obj))
+		return PTR_ERR(obj);
+
+	err = bpf_object__btf_fd(obj);
+	if (err == -1) {
+		fprintf(stderr, "bpf_object__btf_fd: -1\n");
+		goto done;
+	}
+
+	prog = bpf_program__next(NULL, obj);
+	if (!prog) {
+		fprintf(stderr, "Cannot find bpf_prog\n");
+		err = -1;
+		goto done;
+	}
+
+	bpf_program__set_type(prog, BPF_PROG_TYPE_TRACEPOINT);
+	err = bpf_object__load(obj);
+	if (err < 0) {
+		fprintf(stderr, "bpf_object__load: %d\n", err);
+		goto done;
+	}
+
+	map = bpf_object__find_map_by_name(obj, "btf_map");
+	if (!map) {
+		fprintf(stderr, "btf_map not found\n");
+		err = -1;
+		goto done;
+	}
+
+	err = (bpf_map__btf_key_id(map) == 0 || bpf_map__btf_value_id(map) == 0)
+		!= test->btf_kv_notfound;
+	if (err) {
+		fprintf(stderr,
+			"btf_kv_notfound:%u btf_key_id:%u btf_value_id:%u\n",
+			test->btf_kv_notfound,
+			bpf_map__btf_key_id(map),
+			bpf_map__btf_value_id(map));
+		goto done;
+	}
+
+	fprintf(stderr, "OK\n");
+
+done:
+	bpf_object__close(obj);
+	return err;
+}
+
+static int test_file(void)
+{
+	unsigned int i;
+	int err = 0;
+
+	if (args.file_test_num)
+		return do_test_file(args.file_test_num);
+
+	for (i = 1; i <= ARRAY_SIZE(file_tests); i++)
+		err |= do_test_file(i);
+
+	return err;
+}
+
+const char *pprint_enum_str[] = {
+	"ENUM_ZERO",
+	"ENUM_ONE",
+	"ENUM_TWO",
+	"ENUM_THREE",
+};
+
+struct pprint_mapv {
+	uint32_t ui32;
+	uint16_t ui16;
+	/* 2 bytes hole */
+	int32_t si32;
+	uint32_t unused_bits2a:2,
+		bits28:28,
+		unused_bits2b:2;
+	union {
+		uint64_t ui64;
+		uint8_t ui8a[8];
+	};
+	enum {
+		ENUM_ZERO,
+		ENUM_ONE,
+		ENUM_TWO,
+		ENUM_THREE,
+	} aenum;
+};
+
+static struct btf_raw_test pprint_test = {
+	.descr = "BTF pretty print test #1",
+	.raw_types = {
+		/* unsighed char */			/* [1] */
+		BTF_TYPE_INT_ENC(NAME_TBD, 0, 0, 8, 1),
+		/* unsigned short */			/* [2] */
+		BTF_TYPE_INT_ENC(NAME_TBD, 0, 0, 16, 2),
+		/* unsigned int */			/* [3] */
+		BTF_TYPE_INT_ENC(NAME_TBD, 0, 0, 32, 4),
+		/* int */				/* [4] */
+		BTF_TYPE_INT_ENC(NAME_TBD, BTF_INT_SIGNED, 0, 32, 4),
+		/* unsigned long long */		/* [5] */
+		BTF_TYPE_INT_ENC(NAME_TBD, 0, 0, 64, 8),
+		/* 2 bits */				/* [6] */
+		BTF_TYPE_INT_ENC(0, 0, 0, 2, 2),
+		/* 28 bits */				/* [7] */
+		BTF_TYPE_INT_ENC(0, 0, 0, 28, 4),
+		/* uint8_t[8] */			/* [8] */
+		BTF_TYPE_ARRAY_ENC(9, 3, 8),
+		/* typedef unsigned char uint8_t */	/* [9] */
+		BTF_TYPEDEF_ENC(NAME_TBD, 1),
+		/* typedef unsigned short uint16_t */	/* [10] */
+		BTF_TYPEDEF_ENC(NAME_TBD, 2),
+		/* typedef unsigned int uint32_t */	/* [11] */
+		BTF_TYPEDEF_ENC(NAME_TBD, 3),
+		/* typedef int int32_t */		/* [12] */
+		BTF_TYPEDEF_ENC(NAME_TBD, 4),
+		/* typedef unsigned long long uint64_t *//* [13] */
+		BTF_TYPEDEF_ENC(NAME_TBD, 5),
+		/* union (anon) */			/* [14] */
+		BTF_TYPE_ENC(0, BTF_INFO_ENC(BTF_KIND_UNION, 0, 2), 8),
+		BTF_MEMBER_ENC(NAME_TBD, 13, 0),/* uint64_t ui64; */
+		BTF_MEMBER_ENC(NAME_TBD, 8, 0),	/* uint8_t ui8a[8]; */
+		/* enum (anon) */			/* [15] */
+		BTF_TYPE_ENC(0, BTF_INFO_ENC(BTF_KIND_ENUM, 0, 4), 4),
+		BTF_ENUM_ENC(NAME_TBD, 0),
+		BTF_ENUM_ENC(NAME_TBD, 1),
+		BTF_ENUM_ENC(NAME_TBD, 2),
+		BTF_ENUM_ENC(NAME_TBD, 3),
+		/* struct pprint_mapv */		/* [16] */
+		BTF_TYPE_ENC(NAME_TBD, BTF_INFO_ENC(BTF_KIND_STRUCT, 0, 8), 28),
+		BTF_MEMBER_ENC(NAME_TBD, 11, 0),	/* uint32_t ui32 */
+		BTF_MEMBER_ENC(NAME_TBD, 10, 32),	/* uint16_t ui16 */
+		BTF_MEMBER_ENC(NAME_TBD, 12, 64),	/* int32_t si32 */
+		BTF_MEMBER_ENC(NAME_TBD, 6, 96),	/* unused_bits2a */
+		BTF_MEMBER_ENC(NAME_TBD, 7, 98),	/* bits28 */
+		BTF_MEMBER_ENC(NAME_TBD, 6, 126),	/* unused_bits2b */
+		BTF_MEMBER_ENC(0, 14, 128),		/* union (anon) */
+		BTF_MEMBER_ENC(NAME_TBD, 15, 192),	/* aenum */
+		BTF_END_RAW,
+	},
+	.str_sec = "\0unsigned char\0unsigned short\0unsigned int\0int\0unsigned long long\0uint8_t\0uint16_t\0uint32_t\0int32_t\0uint64_t\0ui64\0ui8a\0ENUM_ZERO\0ENUM_ONE\0ENUM_TWO\0ENUM_THREE\0pprint_mapv\0ui32\0ui16\0si32\0unused_bits2a\0bits28\0unused_bits2b\0aenum",
+	.str_sec_size = sizeof("\0unsigned char\0unsigned short\0unsigned int\0int\0unsigned long long\0uint8_t\0uint16_t\0uint32_t\0int32_t\0uint64_t\0ui64\0ui8a\0ENUM_ZERO\0ENUM_ONE\0ENUM_TWO\0ENUM_THREE\0pprint_mapv\0ui32\0ui16\0si32\0unused_bits2a\0bits28\0unused_bits2b\0aenum"),
+	.map_type = BPF_MAP_TYPE_ARRAY,
+	.map_name = "pprint_test",
+	.key_size = sizeof(unsigned int),
+	.value_size = sizeof(struct pprint_mapv),
+	.key_id = 3,	/* unsigned int */
+	.value_id = 16,	/* struct pprint_mapv */
+	.max_entries = 128 * 1024,
+};
+
+static void set_pprint_mapv(struct pprint_mapv *v, uint32_t i)
+{
+	v->ui32 = i;
+	v->si32 = -i;
+	v->unused_bits2a = 3;
+	v->bits28 = i;
+	v->unused_bits2b = 3;
+	v->ui64 = i;
+	v->aenum = i & 0x03;
+}
+
+static int test_pprint(void)
+{
+	const struct btf_raw_test *test = &pprint_test;
+	struct bpf_create_map_attr create_attr = {};
+	int map_fd = -1, btf_fd = -1;
+	struct pprint_mapv mapv = {};
+	unsigned int raw_btf_size;
+	char expected_line[255];
+	FILE *pin_file = NULL;
+	char pin_path[255];
+	size_t line_len = 0;
+	char *line = NULL;
+	unsigned int key;
+	uint8_t *raw_btf;
+	ssize_t nread;
+	int err;
+
+	fprintf(stderr, "%s......", test->descr);
+	raw_btf = btf_raw_create(&hdr_tmpl, test->raw_types,
+				 test->str_sec, test->str_sec_size,
+				 &raw_btf_size);
+
+	if (!raw_btf)
+		return -1;
+
+	*btf_log_buf = '\0';
+	btf_fd = bpf_load_btf(raw_btf, raw_btf_size,
+			      btf_log_buf, BTF_LOG_BUF_SIZE,
+			      args.always_log);
+	free(raw_btf);
+
+	if (btf_fd == -1) {
+		err = -1;
+		fprintf(stderr, "bpf_load_btf: %s(%d)\n",
+			strerror(errno), errno);
+		goto done;
+	}
+
+	create_attr.name = test->map_name;
+	create_attr.map_type = test->map_type;
+	create_attr.key_size = test->key_size;
+	create_attr.value_size = test->value_size;
+	create_attr.max_entries = test->max_entries;
+	create_attr.btf_fd = btf_fd;
+	create_attr.btf_key_id = test->key_id;
+	create_attr.btf_value_id = test->value_id;
+
+	map_fd = bpf_create_map_xattr(&create_attr);
+	if (map_fd == -1) {
+		err = -1;
+		fprintf(stderr, "bpf_creat_map_btf: %s(%d)\n",
+			strerror(errno), errno);
+		goto done;
+	}
+
+	if (snprintf(pin_path, sizeof(pin_path), "%s/%s",
+		     "/sys/fs/bpf", test->map_name) == sizeof(pin_path)) {
+		err = -1;
+		fprintf(stderr, "pin_path is too long\n");
+		goto done;
+	}
+
+	err = bpf_obj_pin(map_fd, pin_path);
+	if (err) {
+		fprintf(stderr, "Cannot pin to %s. %s(%d).\n", pin_path,
+			strerror(errno), errno);
+		goto done;
+	}
+
+	for (key = 0; key < test->max_entries; key++) {
+		set_pprint_mapv(&mapv, key);
+		bpf_map_update_elem(map_fd, &key, &mapv, 0);
+	}
+
+	pin_file = fopen(pin_path, "r");
+	if (!pin_file) {
+		err = -1;
+		fprintf(stderr, "fopen(%s): %s(%d)\n", pin_path,
+			strerror(errno), errno);
+		goto done;
+	}
+
+	/* Skip lines start with '#' */
+	while ((nread = getline(&line, &line_len, pin_file)) > 0 &&
+	       *line == '#')
+		;
+
+	if (nread <= 0) {
+		err = -1;
+		fprintf(stderr, "Unexpected EOF\n");
+		goto done;
+	}
+
+	key = 0;
+	do {
+		ssize_t nexpected_line;
+
+		set_pprint_mapv(&mapv, key);
+		nexpected_line = snprintf(expected_line, sizeof(expected_line),
+					  "%u: {%u,0,%d,0x%x,0x%x,0x%x,{%lu|[%u,%u,%u,%u,%u,%u,%u,%u]},%s}\n",
+					  key,
+					  mapv.ui32, mapv.si32,
+					  mapv.unused_bits2a, mapv.bits28, mapv.unused_bits2b,
+					  mapv.ui64,
+					  mapv.ui8a[0], mapv.ui8a[1], mapv.ui8a[2], mapv.ui8a[3],
+					  mapv.ui8a[4], mapv.ui8a[5], mapv.ui8a[6], mapv.ui8a[7],
+					  pprint_enum_str[mapv.aenum]);
+
+		if (nexpected_line == sizeof(expected_line)) {
+			err = -1;
+			fprintf(stderr, "expected_line is too long\n");
+			goto done;
+		}
+
+		if (strcmp(expected_line, line)) {
+			err = -1;
+			fprintf(stderr, "unexpected pprint output\n");
+			fprintf(stderr, "expected: %s", expected_line);
+			fprintf(stderr, "    read: %s", line);
+			goto done;
+		}
+
+		nread = getline(&line, &line_len, pin_file);
+	} while (++key < test->max_entries && nread > 0);
+
+	if (key < test->max_entries) {
+		err = -1;
+		fprintf(stderr, "Unexpected EOF\n");
+		goto done;
+	}
+
+	if (nread > 0) {
+		err = -1;
+		fprintf(stderr, "Unexpected extra pprint output: %s\n", line);
+		goto done;
+	}
+
+	err = 0;
+
+done:
+	if (!err)
+		fprintf(stderr, "OK\n");
+	if (*btf_log_buf && (err || args.always_log))
+		fprintf(stderr, "%s\n", btf_log_buf);
+	if (btf_fd != -1)
+		close(btf_fd);
+	if (map_fd != -1)
+		close(map_fd);
+	if (pin_file)
+		fclose(pin_file);
+	unlink(pin_path);
+	free(line);
+
+	return err;
+}
+
+static void usage(const char *cmd)
+{
+	fprintf(stderr, "Usage: %s [-l] [[-r test_num (1 - %zu)] | [-g test_num (1 - %zu)] | [-f test_num (1 - %zu)] | [-p]]\n",
+		cmd, ARRAY_SIZE(raw_tests), ARRAY_SIZE(get_info_tests),
+		ARRAY_SIZE(file_tests));
+}
+
+static int parse_args(int argc, char **argv)
+{
+	const char *optstr = "lpf:r:g:";
+	int opt;
+
+	while ((opt = getopt(argc, argv, optstr)) != -1) {
+		switch (opt) {
+		case 'l':
+			args.always_log = true;
+			break;
+		case 'f':
+			args.file_test_num = atoi(optarg);
+			args.file_test = true;
+			break;
+		case 'r':
+			args.raw_test_num = atoi(optarg);
+			args.raw_test = true;
+			break;
+		case 'g':
+			args.get_info_test_num = atoi(optarg);
+			args.get_info_test = true;
+			break;
+		case 'p':
+			args.pprint_test = true;
+			break;
+		case 'h':
+			usage(argv[0]);
+			exit(0);
+		default:
+				usage(argv[0]);
+				return -1;
+		}
+	}
+
+	if (args.raw_test_num &&
+	    (args.raw_test_num < 1 ||
+	     args.raw_test_num > ARRAY_SIZE(raw_tests))) {
+		fprintf(stderr, "BTF raw test number must be [1 - %zu]\n",
+			ARRAY_SIZE(raw_tests));
+		return -1;
+	}
+
+	if (args.file_test_num &&
+	    (args.file_test_num < 1 ||
+	     args.file_test_num > ARRAY_SIZE(file_tests))) {
+		fprintf(stderr, "BTF file test number must be [1 - %zu]\n",
+			ARRAY_SIZE(file_tests));
+		return -1;
+	}
+
+	if (args.get_info_test_num &&
+	    (args.get_info_test_num < 1 ||
+	     args.get_info_test_num > ARRAY_SIZE(get_info_tests))) {
+		fprintf(stderr, "BTF get info test number must be [1 - %zu]\n",
+			ARRAY_SIZE(get_info_tests));
+		return -1;
+	}
+
+	return 0;
+}
+
+int main(int argc, char **argv)
+{
+	int err = 0;
+
+	err = parse_args(argc, argv);
+	if (err)
+		return err;
+
+	if (args.always_log)
+		libbpf_set_print(__base_pr, __base_pr, __base_pr);
+
+	if (args.raw_test)
+		err |= test_raw();
+
+	if (args.get_info_test)
+		err |= test_get_info();
+
+	if (args.file_test)
+		err |= test_file();
+
+	if (args.pprint_test)
+		err |= test_pprint();
+
+	if (args.raw_test || args.get_info_test || args.file_test ||
+	    args.pprint_test)
+		return err;
+
+	err |= test_raw();
+	err |= test_get_info();
+	err |= test_file();
+
+	return err;
+}

tools/testing/selftests/bpf/test_btf_haskv.c

+/* SPDX-License-Identifier: GPL-2.0 */
+/* Copyright (c) 2018 Facebook */
+#include <linux/bpf.h>
+#include "bpf_helpers.h"
+
+int _version SEC("version") = 1;
+
+struct ipv_counts {
+	unsigned int v4;
+	unsigned int v6;
+};
+
+typedef int btf_map_key;
+typedef struct ipv_counts btf_map_value;
+btf_map_key dumm_key;
+btf_map_value dummy_value;
+
+struct bpf_map_def SEC("maps") btf_map = {
+	.type = BPF_MAP_TYPE_ARRAY,
+	.key_size = sizeof(int),
+	.value_size = sizeof(struct ipv_counts),
+	.max_entries = 4,
+};
+
+struct dummy_tracepoint_args {
+	unsigned long long pad;
+	struct sock *sock;
+};
+
+SEC("dummy_tracepoint")
+int _dummy_tracepoint(struct dummy_tracepoint_args *arg)
+{
+	struct ipv_counts *counts;
+	int key = 0;
+
+	if (!arg->sock)
+		return 0;
+
+	counts = bpf_map_lookup_elem(&btf_map, &key);
+	if (!counts)
+		return 0;
+
+	counts->v6++;
+
+	return 0;
+}
+
+char _license[] SEC("license") = "GPL";

tools/testing/selftests/bpf/test_btf_nokv.c

+/* SPDX-License-Identifier: GPL-2.0 */
+/* Copyright (c) 2018 Facebook */
+#include <linux/bpf.h>
+#include "bpf_helpers.h"
+
+int _version SEC("version") = 1;
+
+struct ipv_counts {
+	unsigned int v4;
+	unsigned int v6;
+};
+
+struct bpf_map_def SEC("maps") btf_map = {
+	.type = BPF_MAP_TYPE_ARRAY,
+	.key_size = sizeof(int),
+	.value_size = sizeof(struct ipv_counts),
+	.max_entries = 4,
+};
+
+struct dummy_tracepoint_args {
+	unsigned long long pad;
+	struct sock *sock;
+};
+
+SEC("dummy_tracepoint")
+int _dummy_tracepoint(struct dummy_tracepoint_args *arg)
+{
+	struct ipv_counts *counts;
+	int key = 0;
+
+	if (!arg->sock)
+		return 0;
+
+	counts = bpf_map_lookup_elem(&btf_map, &key);
+	if (!counts)
+		return 0;
+
+	counts->v6++;
+
+	return 0;
+}
+
+char _license[] SEC("license") = "GPL";