Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

Alexei Starovoitov says:

====================
pull-request: bpf-next 2019-05-31

The following pull-request contains BPF updates for your *net-next* tree.

Lots of exciting new features in the first PR of this developement cycle!
The main changes are:

1) misc verifier improvements, from Alexei.

2) bpftool can now convert btf to valid C, from Andrii.

3) verifier can insert explicit ZEXT insn when requested by 32-bit JITs.
   This feature greatly improves BPF speed on 32-bit architectures. From Jiong.

4) cgroups will now auto-detach bpf programs. This fixes issue of thousands
   bpf programs got stuck in dying cgroups. From Roman.

5) new bpf_send_signal() helper, from Yonghong.

6) cgroup inet skb programs can signal CN to the stack, from Lawrence.

7) miscellaneous cleanups, from many developers.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

68 files changed, 5496 insertions, 490 deletions

diff --git a/tools/bpf/bpftool/Documentation/bpftool-btf.rst b/tools/bpf/bpftool/Documentation/bpftool-btf.rst
index 2dbc1413fabd..6694a0fc8f99 100644
--- a/tools/bpf/bpftool/Documentation/bpftool-btf.rst
+++ b/tools/bpf/bpftool/Documentation/bpftool-btf.rst
@@ -19,10 +19,11 @@ SYNOPSIS
 BTF COMMANDS
 =============
 
-|	**bpftool** **btf dump** *BTF_SRC*
+|	**bpftool** **btf dump** *BTF_SRC* [**format** *FORMAT*]
 |	**bpftool** **btf help**
 |
 |	*BTF_SRC* := { **id** *BTF_ID* | **prog** *PROG* | **map** *MAP* [{**key** | **value** | **kv** | **all**}] | **file** *FILE* }
+|	*FORMAT* := { **raw** | **c** }
 |	*MAP* := { **id** *MAP_ID* | **pinned** *FILE* }
 |	*PROG* := { **id** *PROG_ID* | **pinned** *FILE* | **tag** *PROG_TAG* }
 
@@ -31,23 +32,27 @@ DESCRIPTION
 	**bpftool btf dump** *BTF_SRC*
 		  Dump BTF entries from a given *BTF_SRC*.
 
-                  When **id** is specified, BTF object with that ID will be
-                  loaded and all its BTF types emitted.
+		  When **id** is specified, BTF object with that ID will be
+		  loaded and all its BTF types emitted.
 
-                  When **map** is provided, it's expected that map has
-                  associated BTF object with BTF types describing key and
-                  value. It's possible to select whether to dump only BTF
-                  type(s) associated with key (**key**), value (**value**),
-                  both key and value (**kv**), or all BTF types present in
-                  associated BTF object (**all**). If not specified, **kv**
-                  is assumed.
+		  When **map** is provided, it's expected that map has
+		  associated BTF object with BTF types describing key and
+		  value. It's possible to select whether to dump only BTF
+		  type(s) associated with key (**key**), value (**value**),
+		  both key and value (**kv**), or all BTF types present in
+		  associated BTF object (**all**). If not specified, **kv**
+		  is assumed.
 
-                  When **prog** is provided, it's expected that program has
-                  associated BTF object with BTF types.
+		  When **prog** is provided, it's expected that program has
+		  associated BTF object with BTF types.
 
-                  When specifying *FILE*, an ELF file is expected, containing
-                  .BTF section with well-defined BTF binary format data,
-                  typically produced by clang or pahole.
+		  When specifying *FILE*, an ELF file is expected, containing
+		  .BTF section with well-defined BTF binary format data,
+		  typically produced by clang or pahole.
+
+		  **format** option can be used to override default (raw)
+		  output format. Raw (**raw**) or C-syntax (**c**) output
+		  formats are supported.
 
 	**bpftool btf help**
 		  Print short help message.
@@ -67,6 +72,10 @@ OPTIONS
 	-p, --pretty
 		  Generate human-readable JSON output. Implies **-j**.
 
+	-d, --debug
+		  Print all logs available from libbpf, including debug-level
+		  information.
+
 EXAMPLES
 ========
 **# bpftool btf dump id 1226**
diff --git a/tools/bpf/bpftool/Documentation/bpftool-cgroup.rst b/tools/bpf/bpftool/Documentation/bpftool-cgroup.rst
index ac26876389c2..36807735e2a5 100644
--- a/tools/bpf/bpftool/Documentation/bpftool-cgroup.rst
+++ b/tools/bpf/bpftool/Documentation/bpftool-cgroup.rst
@@ -113,6 +113,10 @@ OPTIONS
 	-f, --bpffs
 		  Show file names of pinned programs.
 
+	-d, --debug
+		  Print all logs available from libbpf, including debug-level
+		  information.
+
 EXAMPLES
 ========
 |
diff --git a/tools/bpf/bpftool/Documentation/bpftool-feature.rst b/tools/bpf/bpftool/Documentation/bpftool-feature.rst
index 14180e887082..4d08f35034a2 100644
--- a/tools/bpf/bpftool/Documentation/bpftool-feature.rst
+++ b/tools/bpf/bpftool/Documentation/bpftool-feature.rst
@@ -73,6 +73,10 @@ OPTIONS
 	-p, --pretty
 		  Generate human-readable JSON output. Implies **-j**.
 
+	-d, --debug
+		  Print all logs available from libbpf, including debug-level
+		  information.
+
 SEE ALSO
 ========
 	**bpf**\ (2),
diff --git a/tools/bpf/bpftool/Documentation/bpftool-map.rst b/tools/bpf/bpftool/Documentation/bpftool-map.rst
index 13ef27b39f20..490b4501cb6e 100644
--- a/tools/bpf/bpftool/Documentation/bpftool-map.rst
+++ b/tools/bpf/bpftool/Documentation/bpftool-map.rst
@@ -152,6 +152,10 @@ OPTIONS
 		  Do not automatically attempt to mount any virtual file system
 		  (such as tracefs or BPF virtual file system) when necessary.
 
+	-d, --debug
+		  Print all logs available from libbpf, including debug-level
+		  information.
+
 EXAMPLES
 ========
 **# bpftool map show**
diff --git a/tools/bpf/bpftool/Documentation/bpftool-net.rst b/tools/bpf/bpftool/Documentation/bpftool-net.rst
index 934580850f42..d8e5237a2085 100644
--- a/tools/bpf/bpftool/Documentation/bpftool-net.rst
+++ b/tools/bpf/bpftool/Documentation/bpftool-net.rst
@@ -65,6 +65,10 @@ OPTIONS
 	-p, --pretty
 		  Generate human-readable JSON output. Implies **-j**.
 
+	-d, --debug
+		  Print all logs available from libbpf, including debug-level
+		  information.
+
 EXAMPLES
 ========
 
diff --git a/tools/bpf/bpftool/Documentation/bpftool-perf.rst b/tools/bpf/bpftool/Documentation/bpftool-perf.rst
index 0c7576523a21..e252bd0bc434 100644
--- a/tools/bpf/bpftool/Documentation/bpftool-perf.rst
+++ b/tools/bpf/bpftool/Documentation/bpftool-perf.rst
@@ -53,6 +53,10 @@ OPTIONS
 	-p, --pretty
 		  Generate human-readable JSON output. Implies **-j**.
 
+	-d, --debug
+		  Print all logs available from libbpf, including debug-level
+		  information.
+
 EXAMPLES
 ========
 
diff --git a/tools/bpf/bpftool/Documentation/bpftool-prog.rst b/tools/bpf/bpftool/Documentation/bpftool-prog.rst
index e8118544d118..228a5c863cc7 100644
--- a/tools/bpf/bpftool/Documentation/bpftool-prog.rst
+++ b/tools/bpf/bpftool/Documentation/bpftool-prog.rst
@@ -174,6 +174,11 @@ OPTIONS
 		  Do not automatically attempt to mount any virtual file system
 		  (such as tracefs or BPF virtual file system) when necessary.
 
+	-d, --debug
+		  Print all logs available, even debug-level information. This
+		  includes logs from libbpf as well as from the verifier, when
+		  attempting to load programs.
+
 EXAMPLES
 ========
 **# bpftool prog show**
diff --git a/tools/bpf/bpftool/Documentation/bpftool.rst b/tools/bpf/bpftool/Documentation/bpftool.rst
index 3e562d7fd56f..6a9c52ef84a9 100644
--- a/tools/bpf/bpftool/Documentation/bpftool.rst
+++ b/tools/bpf/bpftool/Documentation/bpftool.rst
@@ -66,6 +66,10 @@ OPTIONS
 		  Do not automatically attempt to mount any virtual file system
 		  (such as tracefs or BPF virtual file system) when necessary.
 
+	-d, --debug
+		  Print all logs available, even debug-level information. This
+		  includes logs from libbpf as well as from the verifier, when
+		  attempting to load programs.
 
 SEE ALSO
 ========
diff --git a/tools/bpf/bpftool/bash-completion/bpftool b/tools/bpf/bpftool/bash-completion/bpftool
index 50e402a5a9c8..2725e27dfa42 100644
--- a/tools/bpf/bpftool/bash-completion/bpftool
+++ b/tools/bpf/bpftool/bash-completion/bpftool
@@ -71,6 +71,12 @@ _bpftool_get_prog_tags()
         command sed -n 's/.*"tag": "\(.*\)",$/\1/p' )" -- "$cur" ) )
 }
 
+_bpftool_get_btf_ids()
+{
+    COMPREPLY+=( $( compgen -W "$( bpftool -jp prog 2>&1 | \
+        command sed -n 's/.*"btf_id": \(.*\),\?$/\1/p' )" -- "$cur" ) )
+}
+
 _bpftool_get_obj_map_names()
 {
     local obj
@@ -181,7 +187,7 @@ _bpftool()
 
     # Deal with options
     if [[ ${words[cword]} == -* ]]; then
-        local c='--version --json --pretty --bpffs --mapcompat'
+        local c='--version --json --pretty --bpffs --mapcompat --debug'
         COMPREPLY=( $( compgen -W "$c" -- "$cur" ) )
         return 0
     fi
@@ -635,14 +641,30 @@ _bpftool()
                                 map)
                                     _bpftool_get_map_ids
                                     ;;
+                                dump)
+                                    _bpftool_get_btf_ids
+                                    ;;
                             esac
                             return 0
                             ;;
+                        format)
+                            COMPREPLY=( $( compgen -W "c raw" -- "$cur" ) )
+                            ;;
                         *)
-                            if [[ $cword == 6 ]] && [[ ${words[3]} == "map" ]]; then
-                                 COMPREPLY+=( $( compgen -W 'key value kv all' -- \
-                                     "$cur" ) )
-                            fi
+                            # emit extra options
+                            case ${words[3]} in
+                                id|file)
+                                    _bpftool_once_attr 'format'
+                                    ;;
+                                map|prog)
+                                    if [[ ${words[3]} == "map" ]] && [[ $cword == 6 ]]; then
+                                        COMPREPLY+=( $( compgen -W "key value kv all" -- "$cur" ) )
+                                    fi
+                                    _bpftool_once_attr 'format'
+                                    ;;
+                                *)
+                                    ;;
+                            esac
                             return 0
                             ;;
                     esac
diff --git a/tools/bpf/bpftool/btf.c b/tools/bpf/bpftool/btf.c
index 7317438ecd9e..1b8ec91899e6 100644
--- a/tools/bpf/bpftool/btf.c
+++ b/tools/bpf/bpftool/btf.c
@@ -8,8 +8,8 @@
 #include <stdio.h>
 #include <string.h>
 #include <unistd.h>
-#include <gelf.h>
 #include <bpf.h>
+#include <libbpf.h>
 #include <linux/btf.h>
 
 #include "btf.h"
@@ -340,109 +340,40 @@ static int dump_btf_raw(const struct btf *btf,
 	return 0;
 }
 
-static bool check_btf_endianness(GElf_Ehdr *ehdr)
+static void __printf(2, 0) btf_dump_printf(void *ctx,
+					   const char *fmt, va_list args)
 {
-	static unsigned int const endian = 1;
-
-	switch (ehdr->e_ident[EI_DATA]) {
-	case ELFDATA2LSB:
-		return *(unsigned char const *)&endian == 1;
-	case ELFDATA2MSB:
-		return *(unsigned char const *)&endian == 0;
-	default:
-		return 0;
-	}
+	vfprintf(stdout, fmt, args);
 }
 
-static int btf_load_from_elf(const char *path, struct btf **btf)
+static int dump_btf_c(const struct btf *btf,
+		      __u32 *root_type_ids, int root_type_cnt)
 {
-	int err = -1, fd = -1, idx = 0;
-	Elf_Data *btf_data = NULL;
-	Elf_Scn *scn = NULL;
-	Elf *elf = NULL;
-	GElf_Ehdr ehdr;
-
-	if (elf_version(EV_CURRENT) == EV_NONE) {
-		p_err("failed to init libelf for %s", path);
-		return -1;
-	}
-
-	fd = open(path, O_RDONLY);
-	if (fd < 0) {
-		p_err("failed to open %s: %s", path, strerror(errno));
-		return -1;
-	}
-
-	elf = elf_begin(fd, ELF_C_READ, NULL);
-	if (!elf) {
-		p_err("failed to open %s as ELF file", path);
-		goto done;
-	}
-	if (!gelf_getehdr(elf, &ehdr)) {
-		p_err("failed to get EHDR from %s", path);
-		goto done;
-	}
-	if (!check_btf_endianness(&ehdr)) {
-		p_err("non-native ELF endianness is not supported");
-		goto done;
-	}
-	if (!elf_rawdata(elf_getscn(elf, ehdr.e_shstrndx), NULL)) {
-		p_err("failed to get e_shstrndx from %s\n", path);
-		goto done;
-	}
+	struct btf_dump *d;
+	int err = 0, i;
 
-	while ((scn = elf_nextscn(elf, scn)) != NULL) {
-		GElf_Shdr sh;
-		char *name;
+	d = btf_dump__new(btf, NULL, NULL, btf_dump_printf);
+	if (IS_ERR(d))
+		return PTR_ERR(d);
 
-		idx++;
-		if (gelf_getshdr(scn, &sh) != &sh) {
-			p_err("failed to get section(%d) header from %s",
-			      idx, path);
-			goto done;
-		}
-		name = elf_strptr(elf, ehdr.e_shstrndx, sh.sh_name);
-		if (!name) {
-			p_err("failed to get section(%d) name from %s",
-			      idx, path);
-			goto done;
-		}
-		if (strcmp(name, BTF_ELF_SEC) == 0) {
-			btf_data = elf_getdata(scn, 0);
-			if (!btf_data) {
-				p_err("failed to get section(%d, %s) data from %s",
-				      idx, name, path);
+	if (root_type_cnt) {
+		for (i = 0; i < root_type_cnt; i++) {
+			err = btf_dump__dump_type(d, root_type_ids[i]);
+			if (err)
 				goto done;
-			}
-			break;
 		}
-	}
-
-	if (!btf_data) {
-		p_err("%s ELF section not found in %s", BTF_ELF_SEC, path);
-		goto done;
-	}
+	} else {
+		int cnt = btf__get_nr_types(btf);
 
-	*btf = btf__new(btf_data->d_buf, btf_data->d_size);
-	if (IS_ERR(*btf)) {
-		err = PTR_ERR(*btf);
-		*btf = NULL;
-		p_err("failed to load BTF data from %s: %s",
-		      path, strerror(err));
-		goto done;
+		for (i = 1; i <= cnt; i++) {
+			err = btf_dump__dump_type(d, i);
+			if (err)
+				goto done;
+		}
 	}
 
-	err = 0;
 done:
-	if (err) {
-		if (*btf) {
-			btf__free(*btf);
-			*btf = NULL;
-		}
-	}
-	if (elf)
-		elf_end(elf);
-	close(fd);
+	btf_dump__free(d);
 	return err;
 }
 
@@ -451,6 +382,7 @@ static int do_dump(int argc, char **argv)
 	struct btf *btf = NULL;
 	__u32 root_type_ids[2];
 	int root_type_cnt = 0;
+	bool dump_c = false;
 	__u32 btf_id = -1;
 	const char *src;
 	int fd = -1;
@@ -522,9 +454,14 @@ static int do_dump(int argc, char **argv)
 		}
 		NEXT_ARG();
 	} else if (is_prefix(src, "file")) {
-		err = btf_load_from_elf(*argv, &btf);
-		if (err)
+		btf = btf__parse_elf(*argv, NULL);
+		if (IS_ERR(btf)) {
+			err = PTR_ERR(btf);
+			btf = NULL;
+			p_err("failed to load BTF from %s: %s", 
+			      *argv, strerror(err));
 			goto done;
+		}
 		NEXT_ARG();
 	} else {
 		err = -1;
@@ -532,6 +469,29 @@ static int do_dump(int argc, char **argv)
 		goto done;
 	}
 
+	while (argc) {
+		if (is_prefix(*argv, "format")) {
+			NEXT_ARG();
+			if (argc < 1) {
+				p_err("expecting value for 'format' option\n");
+				goto done;
+			}
+			if (strcmp(*argv, "c") == 0) {
+				dump_c = true;
+			} else if (strcmp(*argv, "raw") == 0) {
+				dump_c = false;
+			} else {
+				p_err("unrecognized format specifier: '%s', possible values: raw, c",
+				      *argv);
+				goto done;
+			}
+			NEXT_ARG();
+		} else {
+			p_err("unrecognized option: '%s'", *argv);
+			goto done;
+		}
+	}
+
 	if (!btf) {
 		err = btf__get_from_id(btf_id, &btf);
 		if (err) {
@@ -545,7 +505,16 @@ static int do_dump(int argc, char **argv)
 		}
 	}
 
-	dump_btf_raw(btf, root_type_ids, root_type_cnt);
+	if (dump_c) {
+		if (json_output) {
+			p_err("JSON output for C-syntax dump is not supported");
+			err = -ENOTSUP;
+			goto done;
+		}
+		err = dump_btf_c(btf, root_type_ids, root_type_cnt);
+	} else {
+		err = dump_btf_raw(btf, root_type_ids, root_type_cnt);
+	}
 
 done:
 	close(fd);
@@ -561,10 +530,11 @@ static int do_help(int argc, char **argv)
 	}
 
 	fprintf(stderr,
-		"Usage: %s btf dump BTF_SRC\n"
+		"Usage: %s btf dump BTF_SRC [format FORMAT]\n"
 		"       %s btf help\n"
 		"\n"
 		"       BTF_SRC := { id BTF_ID | prog PROG | map MAP [{key | value | kv | all}] | file FILE }\n"
+		"       FORMAT  := { raw | c }\n"
 		"       " HELP_SPEC_MAP "\n"
 		"       " HELP_SPEC_PROGRAM "\n"
 		"       " HELP_SPEC_OPTIONS "\n"
diff --git a/tools/bpf/bpftool/main.c b/tools/bpf/bpftool/main.c
index 1ac1fc520e6a..4879f6395c7e 100644
--- a/tools/bpf/bpftool/main.c
+++ b/tools/bpf/bpftool/main.c
@@ -10,6 +10,7 @@
 #include <string.h>
 
 #include <bpf.h>
+#include <libbpf.h>
 
 #include "main.h"
 
@@ -25,6 +26,7 @@ bool pretty_output;
 bool json_output;
 bool show_pinned;
 bool block_mount;
+bool verifier_logs;
 int bpf_flags;
 struct pinned_obj_table prog_table;
 struct pinned_obj_table map_table;
@@ -77,6 +79,13 @@ static int do_version(int argc, char **argv)
 	return 0;
 }
 
+static int __printf(2, 0)
+print_all_levels(__maybe_unused enum libbpf_print_level level,
+		 const char *format, va_list args)
+{
+	return vfprintf(stderr, format, args);
+}
+
 int cmd_select(const struct cmd *cmds, int argc, char **argv,
 	       int (*help)(int argc, char **argv))
 {
@@ -317,6 +326,7 @@ int main(int argc, char **argv)
 		{ "bpffs",	no_argument,	NULL,	'f' },
 		{ "mapcompat",	no_argument,	NULL,	'm' },
 		{ "nomount",	no_argument,	NULL,	'n' },
+		{ "debug",	no_argument,	NULL,	'd' },
 		{ 0 }
 	};
 	int opt, ret;
@@ -332,7 +342,7 @@ int main(int argc, char **argv)
 	hash_init(map_table.table);
 
 	opterr = 0;
-	while ((opt = getopt_long(argc, argv, "Vhpjfmn",
+	while ((opt = getopt_long(argc, argv, "Vhpjfmnd",
 				  options, NULL)) >= 0) {
 		switch (opt) {
 		case 'V':
@@ -362,6 +372,10 @@ int main(int argc, char **argv)
 		case 'n':
 			block_mount = true;
 			break;
+		case 'd':
+			libbpf_set_print(print_all_levels);
+			verifier_logs = true;
+			break;
 		default:
 			p_err("unrecognized option '%s'", argv[optind - 1]);
 			if (json_output)
diff --git a/tools/bpf/bpftool/main.h b/tools/bpf/bpftool/main.h
index 3d63feb7f852..28a2a5857e14 100644
--- a/tools/bpf/bpftool/main.h
+++ b/tools/bpf/bpftool/main.h
@@ -91,6 +91,7 @@ extern json_writer_t *json_wtr;
 extern bool json_output;
 extern bool show_pinned;
 extern bool block_mount;
+extern bool verifier_logs;
 extern int bpf_flags;
 extern struct pinned_obj_table prog_table;
 extern struct pinned_obj_table map_table;
diff --git a/tools/bpf/bpftool/prog.c b/tools/bpf/bpftool/prog.c
index 26336bad0442..1f209c80d906 100644
--- a/tools/bpf/bpftool/prog.c
+++ b/tools/bpf/bpftool/prog.c
@@ -750,10 +750,11 @@ static int do_detach(int argc, char **argv)
 
 static int load_with_options(int argc, char **argv, bool first_prog_only)
 {
-	enum bpf_attach_type expected_attach_type;
-	struct bpf_object_open_attr attr = {
-		.prog_type	= BPF_PROG_TYPE_UNSPEC,
+	struct bpf_object_load_attr load_attr = { 0 };
+	struct bpf_object_open_attr open_attr = {
+		.prog_type = BPF_PROG_TYPE_UNSPEC,
 	};
+	enum bpf_attach_type expected_attach_type;
 	struct map_replace *map_replace = NULL;
 	struct bpf_program *prog = NULL, *pos;
 	unsigned int old_map_fds = 0;
@@ -767,7 +768,7 @@ static int load_with_options(int argc, char **argv, bool first_prog_only)
 
 	if (!REQ_ARGS(2))
 		return -1;
-	attr.file = GET_ARG();
+	open_attr.file = GET_ARG();
 	pinfile = GET_ARG();
 
 	while (argc) {
@@ -776,7 +777,7 @@ static int load_with_options(int argc, char **argv, bool first_prog_only)
 
 			NEXT_ARG();
 
-			if (attr.prog_type != BPF_PROG_TYPE_UNSPEC) {
+			if (open_attr.prog_type != BPF_PROG_TYPE_UNSPEC) {
 				p_err("program type already specified");
 				goto err_free_reuse_maps;
 			}
@@ -793,7 +794,8 @@ static int load_with_options(int argc, char **argv, bool first_prog_only)
 			strcat(type, *argv);
 			strcat(type, "/");
 
-			err = libbpf_prog_type_by_name(type, &attr.prog_type,
+			err = libbpf_prog_type_by_name(type,
+						       &open_attr.prog_type,
 						       &expected_attach_type);
 			free(type);
 			if (err < 0)
@@ -881,16 +883,16 @@ static int load_with_options(int argc, char **argv, bool first_prog_only)
 
 	set_max_rlimit();
 
-	obj = __bpf_object__open_xattr(&attr, bpf_flags);
+	obj = __bpf_object__open_xattr(&open_attr, bpf_flags);
 	if (IS_ERR_OR_NULL(obj)) {
 		p_err("failed to open object file");
 		goto err_free_reuse_maps;
 	}
 
 	bpf_object__for_each_program(pos, obj) {
-		enum bpf_prog_type prog_type = attr.prog_type;
+		enum bpf_prog_type prog_type = open_attr.prog_type;
 
-		if (attr.prog_type == BPF_PROG_TYPE_UNSPEC) {
+		if (open_attr.prog_type == BPF_PROG_TYPE_UNSPEC) {
 			const char *sec_name = bpf_program__title(pos, false);
 
 			err = libbpf_prog_type_by_name(sec_name, &prog_type,
@@ -960,7 +962,12 @@ static int load_with_options(int argc, char **argv, bool first_prog_only)
 		goto err_close_obj;
 	}
 
-	err = bpf_object__load(obj);
+	load_attr.obj = obj;
+	if (verifier_logs)
+		/* log_level1 + log_level2 + stats, but not stable UAPI */
+		load_attr.log_level = 1 + 2 + 4;
+
+	err = bpf_object__load_xattr(&load_attr);
 	if (err) {
 		p_err("failed to load object file");
 		goto err_close_obj;
diff --git a/tools/bpf/bpftool/xlated_dumper.c b/tools/bpf/bpftool/xlated_dumper.c
index 0bb17bf88b18..494d7ae3614d 100644
--- a/tools/bpf/bpftool/xlated_dumper.c
+++ b/tools/bpf/bpftool/xlated_dumper.c
@@ -31,9 +31,7 @@ void kernel_syms_load(struct dump_data *dd)
 	if (!fp)
 		return;
 
-	while (!feof(fp)) {
-		if (!fgets(buff, sizeof(buff), fp))
-			break;
+	while (fgets(buff, sizeof(buff), fp)) {
 		tmp = reallocarray(dd->sym_mapping, dd->sym_count + 1,
 				   sizeof(*dd->sym_mapping));
 		if (!tmp) {
diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h
index 63e0cf66f01a..7c6aef253173 100644
--- a/tools/include/uapi/linux/bpf.h
+++ b/tools/include/uapi/linux/bpf.h
@@ -260,6 +260,24 @@ enum bpf_attach_type {
  */
 #define BPF_F_ANY_ALIGNMENT	(1U << 1)
 
+/* BPF_F_TEST_RND_HI32 is used in BPF_PROG_LOAD command for testing purpose.
+ * Verifier does sub-register def/use analysis and identifies instructions whose
+ * def only matters for low 32-bit, high 32-bit is never referenced later
+ * through implicit zero extension. Therefore verifier notifies JIT back-ends
+ * that it is safe to ignore clearing high 32-bit for these instructions. This
+ * saves some back-ends a lot of code-gen. However such optimization is not
+ * necessary on some arches, for example x86_64, arm64 etc, whose JIT back-ends
+ * hence hasn't used verifier's analysis result. But, we really want to have a
+ * way to be able to verify the correctness of the described optimization on
+ * x86_64 on which testsuites are frequently exercised.
+ *
+ * So, this flag is introduced. Once it is set, verifier will randomize high
+ * 32-bit for those instructions who has been identified as safe to ignore them.
+ * Then, if verifier is not doing correct analysis, such randomization will
+ * regress tests to expose bugs.
+ */
+#define BPF_F_TEST_RND_HI32	(1U << 2)
+
 /* When BPF ldimm64's insn[0].src_reg != 0 then this can have
  * two extensions:
  *
@@ -2672,6 +2690,20 @@ union bpf_attr {
  *		0 on success.
  *
  *		**-ENOENT** if the bpf-local-storage cannot be found.
+ *
+ * int bpf_send_signal(u32 sig)
+ *	Description
+ *		Send signal *sig* to the current task.
+ *	Return
+ *		0 on success or successfully queued.
+ *
+ *		**-EBUSY** if work queue under nmi is full.
+ *
+ *		**-EINVAL** if *sig* is invalid.
+ *
+ *		**-EPERM** if no permission to send the *sig*.
+ *
+ *		**-EAGAIN** if bpf program can try again.
  */
 #define __BPF_FUNC_MAPPER(FN)		\
 	FN(unspec),			\
@@ -2782,7 +2814,8 @@ union bpf_attr {
 	FN(strtol),			\
 	FN(strtoul),			\
 	FN(sk_storage_get),		\
-	FN(sk_storage_delete),
+	FN(sk_storage_delete),		\
+	FN(send_signal),
 
 /* integer value in 'imm' field of BPF_CALL instruction selects which helper
  * function eBPF program intends to call
diff --git a/tools/include/uapi/linux/if_tun.h b/tools/include/uapi/linux/if_tun.h
new file mode 100644
index 000000000000..454ae31b93c7
--- /dev/null
+++ b/tools/include/uapi/linux/if_tun.h
@@ -0,0 +1,114 @@
+/* SPDX-License-Identifier: GPL-2.0+ WITH Linux-syscall-note */
+/*
+ *  Universal TUN/TAP device driver.
+ *  Copyright (C) 1999-2000 Maxim Krasnyansky <max_mk@yahoo.com>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ *  GNU General Public License for more details.
+ */
+
+#ifndef _UAPI__IF_TUN_H
+#define _UAPI__IF_TUN_H
+
+#include <linux/types.h>
+#include <linux/if_ether.h>
+#include <linux/filter.h>
+
+/* Read queue size */
+#define TUN_READQ_SIZE	500
+/* TUN device type flags: deprecated. Use IFF_TUN/IFF_TAP instead. */
+#define TUN_TUN_DEV 	IFF_TUN
+#define TUN_TAP_DEV	IFF_TAP
+#define TUN_TYPE_MASK   0x000f
+
+/* Ioctl defines */
+#define TUNSETNOCSUM  _IOW('T', 200, int) 
+#define TUNSETDEBUG   _IOW('T', 201, int) 
+#define TUNSETIFF     _IOW('T', 202, int) 
+#define TUNSETPERSIST _IOW('T', 203, int) 
+#define TUNSETOWNER   _IOW('T', 204, int)
+#define TUNSETLINK    _IOW('T', 205, int)
+#define TUNSETGROUP   _IOW('T', 206, int)
+#define TUNGETFEATURES _IOR('T', 207, unsigned int)
+#define TUNSETOFFLOAD  _IOW('T', 208, unsigned int)
+#define TUNSETTXFILTER _IOW('T', 209, unsigned int)
+#define TUNGETIFF      _IOR('T', 210, unsigned int)
+#define TUNGETSNDBUF   _IOR('T', 211, int)
+#define TUNSETSNDBUF   _IOW('T', 212, int)
+#define TUNATTACHFILTER _IOW('T', 213, struct sock_fprog)
+#define TUNDETACHFILTER _IOW('T', 214, struct sock_fprog)
+#define TUNGETVNETHDRSZ _IOR('T', 215, int)
+#define TUNSETVNETHDRSZ _IOW('T', 216, int)
+#define TUNSETQUEUE  _IOW('T', 217, int)
+#define TUNSETIFINDEX	_IOW('T', 218, unsigned int)
+#define TUNGETFILTER _IOR('T', 219, struct sock_fprog)
+#define TUNSETVNETLE _IOW('T', 220, int)
+#define TUNGETVNETLE _IOR('T', 221, int)
+/* The TUNSETVNETBE and TUNGETVNETBE ioctls are for cross-endian support on
+ * little-endian hosts. Not all kernel configurations support them, but all
+ * configurations that support SET also support GET.
+ */
+#define TUNSETVNETBE _IOW('T', 222, int)
+#define TUNGETVNETBE _IOR('T', 223, int)
+#define TUNSETSTEERINGEBPF _IOR('T', 224, int)
+#define TUNSETFILTEREBPF _IOR('T', 225, int)
+#define TUNSETCARRIER _IOW('T', 226, int)
+#define TUNGETDEVNETNS _IO('T', 227)
+
+/* TUNSETIFF ifr flags */
+#define IFF_TUN		0x0001
+#define IFF_TAP		0x0002
+#define IFF_NAPI	0x0010
+#define IFF_NAPI_FRAGS	0x0020
+#define IFF_NO_PI	0x1000
+/* This flag has no real effect */
+#define IFF_ONE_QUEUE	0x2000
+#define IFF_VNET_HDR	0x4000
+#define IFF_TUN_EXCL	0x8000
+#define IFF_MULTI_QUEUE 0x0100
+#define IFF_ATTACH_QUEUE 0x0200
+#define IFF_DETACH_QUEUE 0x0400
+/* read-only flag */
+#define IFF_PERSIST	0x0800
+#define IFF_NOFILTER	0x1000
+
+/* Socket options */
+#define TUN_TX_TIMESTAMP 1
+
+/* Features for GSO (TUNSETOFFLOAD). */
+#define TUN_F_CSUM	0x01	/* You can hand me unchecksummed packets. */
+#define TUN_F_TSO4	0x02	/* I can handle TSO for IPv4 packets */
+#define TUN_F_TSO6	0x04	/* I can handle TSO for IPv6 packets */
+#define TUN_F_TSO_ECN	0x08	/* I can handle TSO with ECN bits. */
+#define TUN_F_UFO	0x10	/* I can handle UFO packets */
+
+/* Protocol info prepended to the packets (when IFF_NO_PI is not set) */
+#define TUN_PKT_STRIP	0x0001
+struct tun_pi {
+	__u16  flags;
+	__be16 proto;
+};
+
+/*
+ * Filter spec (used for SETXXFILTER ioctls)
+ * This stuff is applicable only to the TAP (Ethernet) devices.
+ * If the count is zero the filter is disabled and the driver accepts
+ * all packets (promisc mode).
+ * If the filter is enabled in order to accept broadcast packets
+ * broadcast addr must be explicitly included in the addr list.
+ */
+#define TUN_FLT_ALLMULTI 0x0001 /* Accept all multicast packets */
+struct tun_filter {
+	__u16  flags; /* TUN_FLT_ flags see above */
+	__u16  count; /* Number of addresses */
+	__u8   addr[0][ETH_ALEN];
+};
+
+#endif /* _UAPI__IF_TUN_H */
diff --git a/tools/lib/bpf/Build b/tools/lib/bpf/Build
index ee9d5362f35b..e3962cfbc9a6 100644
--- a/tools/lib/bpf/Build
+++ b/tools/lib/bpf/Build
@@ -1 +1,3 @@
-libbpf-y := libbpf.o bpf.o nlattr.o btf.o libbpf_errno.o str_error.o netlink.o bpf_prog_linfo.o libbpf_probes.o xsk.o
+libbpf-y := libbpf.o bpf.o nlattr.o btf.o libbpf_errno.o str_error.o \
+	    netlink.o bpf_prog_linfo.o libbpf_probes.o xsk.o hashmap.o \
+	    btf_dump.o
diff --git a/tools/lib/bpf/Makefile b/tools/lib/bpf/Makefile
index f91639bf5650..9312066a1ae3 100644
--- a/tools/lib/bpf/Makefile
+++ b/tools/lib/bpf/Makefile
@@ -3,7 +3,7 @@
 
 BPF_VERSION = 0
 BPF_PATCHLEVEL = 0
-BPF_EXTRAVERSION = 3
+BPF_EXTRAVERSION = 4
 
 MAKEFLAGS += --no-print-directory
 
@@ -204,6 +204,16 @@ check_abi: $(OUTPUT)libbpf.so
 		     "versioned symbols in $^ ($(VERSIONED_SYM_COUNT))." \
 		     "Please make sure all LIBBPF_API symbols are"	 \
 		     "versioned in $(VERSION_SCRIPT)." >&2;		 \
+		readelf -s --wide $(OUTPUT)libbpf-in.o |		 \
+		    awk '/GLOBAL/ && /DEFAULT/ && !/UND/ {print $$8}'|   \
+		    sort -u > $(OUTPUT)libbpf_global_syms.tmp;		 \
+		readelf -s --wide $(OUTPUT)libbpf.so |			 \
+		    grep -Eo '[^ ]+@LIBBPF_' | cut -d@ -f1 |		 \
+		    sort -u > $(OUTPUT)libbpf_versioned_syms.tmp; 	 \
+		diff -u $(OUTPUT)libbpf_global_syms.tmp			 \
+		     $(OUTPUT)libbpf_versioned_syms.tmp;		 \
+		rm $(OUTPUT)libbpf_global_syms.tmp			 \
+		   $(OUTPUT)libbpf_versioned_syms.tmp;			 \
 		exit 1;							 \
 	fi
 
diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c
index c4a48086dc9a..0d4b4fe10a84 100644
--- a/tools/lib/bpf/bpf.c
+++ b/tools/lib/bpf/bpf.c
@@ -256,6 +256,7 @@ int bpf_load_program_xattr(const struct bpf_load_program_attr *load_attr,
 	if (load_attr->name)
 		memcpy(attr.prog_name, load_attr->name,
 		       min(strlen(load_attr->name), BPF_OBJ_NAME_LEN - 1));
+	attr.prog_flags = load_attr->prog_flags;
 
 	fd = sys_bpf_prog_load(&attr, sizeof(attr));
 	if (fd >= 0)
diff --git a/tools/lib/bpf/bpf.h b/tools/lib/bpf/bpf.h
index 9593fec75652..ff42ca043dc8 100644
--- a/tools/lib/bpf/bpf.h
+++ b/tools/lib/bpf/bpf.h
@@ -87,6 +87,7 @@ struct bpf_load_program_attr {
 	const void *line_info;
 	__u32 line_info_cnt;
 	__u32 log_level;
+	__u32 prog_flags;
 };
 
 /* Flags to direct loading requirements */
diff --git a/tools/lib/bpf/btf.c b/tools/lib/bpf/btf.c
index 03348c4d6bd4..b2478e98c367 100644
--- a/tools/lib/bpf/btf.c
+++ b/tools/lib/bpf/btf.c
@@ -4,14 +4,17 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <fcntl.h>
 #include <unistd.h>
 #include <errno.h>
 #include <linux/err.h>
 #include <linux/btf.h>
+#include <gelf.h>
 #include "btf.h"
 #include "bpf.h"
 #include "libbpf.h"
 #include "libbpf_internal.h"
+#include "hashmap.h"
 
 #define max(a, b) ((a) > (b) ? (a) : (b))
 #define min(a, b) ((a) < (b) ? (a) : (b))
@@ -417,6 +420,132 @@ done:
 	return btf;
 }
 
+static bool btf_check_endianness(const GElf_Ehdr *ehdr)
+{
+#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
+	return ehdr->e_ident[EI_DATA] == ELFDATA2LSB;
+#elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
+	return ehdr->e_ident[EI_DATA] == ELFDATA2MSB;
+#else
+# error "Unrecognized __BYTE_ORDER__"
+#endif
+}
+
+struct btf *btf__parse_elf(const char *path, struct btf_ext **btf_ext)
+{
+	Elf_Data *btf_data = NULL, *btf_ext_data = NULL;
+	int err = 0, fd = -1, idx = 0;
+	struct btf *btf = NULL;
+	Elf_Scn *scn = NULL;
+	Elf *elf = NULL;
+	GElf_Ehdr ehdr;
+
+	if (elf_version(EV_CURRENT) == EV_NONE) {
+		pr_warning("failed to init libelf for %s\n", path);
+		return ERR_PTR(-LIBBPF_ERRNO__LIBELF);
+	}
+
+	fd = open(path, O_RDONLY);
+	if (fd < 0) {
+		err = -errno;
+		pr_warning("failed to open %s: %s\n", path, strerror(errno));
+		return ERR_PTR(err);
+	}
+
+	err = -LIBBPF_ERRNO__FORMAT;
+
+	elf = elf_begin(fd, ELF_C_READ, NULL);
+	if (!elf) {
+		pr_warning("failed to open %s as ELF file\n", path);
+		goto done;
+	}
+	if (!gelf_getehdr(elf, &ehdr)) {
+		pr_warning("failed to get EHDR from %s\n", path);
+		goto done;
+	}
+	if (!btf_check_endianness(&ehdr)) {
+		pr_warning("non-native ELF endianness is not supported\n");
+		goto done;
+	}
+	if (!elf_rawdata(elf_getscn(elf, ehdr.e_shstrndx), NULL)) {
+		pr_warning("failed to get e_shstrndx from %s\n", path);
+		goto done;
+	}
+
+	while ((scn = elf_nextscn(elf, scn)) != NULL) {
+		GElf_Shdr sh;
+		char *name;
+
+		idx++;
+		if (gelf_getshdr(scn, &sh) != &sh) {
+			pr_warning("failed to get section(%d) header from %s\n",
+				   idx, path);
+			goto done;
+		}
+		name = elf_strptr(elf, ehdr.e_shstrndx, sh.sh_name);
+		if (!name) {
+			pr_warning("failed to get section(%d) name from %s\n",
+				   idx, path);
+			goto done;
+		}
+		if (strcmp(name, BTF_ELF_SEC) == 0) {
+			btf_data = elf_getdata(scn, 0);
+			if (!btf_data) {
+				pr_warning("failed to get section(%d, %s) data from %s\n",
+					   idx, name, path);
+				goto done;
+			}
+			continue;
+		} else if (btf_ext && strcmp(name, BTF_EXT_ELF_SEC) == 0) {
+			btf_ext_data = elf_getdata(scn, 0);
+			if (!btf_ext_data) {
+				pr_warning("failed to get section(%d, %s) data from %s\n",
+					   idx, name, path);
+				goto done;
+			}
+			continue;
+		}
+	}
+
+	err = 0;
+
+	if (!btf_data) {
+		err = -ENOENT;
+		goto done;
+	}
+	btf = btf__new(btf_data->d_buf, btf_data->d_size);
+	if (IS_ERR(btf))
+		goto done;
+
+	if (btf_ext && btf_ext_data) {
+		*btf_ext = btf_ext__new(btf_ext_data->d_buf,
+					btf_ext_data->d_size);
+		if (IS_ERR(*btf_ext))
+			goto done;
+	} else if (btf_ext) {
+		*btf_ext = NULL;
+	}
+done:
+	if (elf)
+		elf_end(elf);
+	close(fd);
+
+	if (err)
+		return ERR_PTR(err);
+	/*
+	 * btf is always parsed before btf_ext, so no need to clean up
+	 * btf_ext, if btf loading failed
+	 */
+	if (IS_ERR(btf))
+		return btf;
+	if (btf_ext && IS_ERR(*btf_ext)) {
+		btf__free(btf);
+		err = PTR_ERR(*btf_ext);
+		return ERR_PTR(err);
+	}
+	return btf;
+}
+
 static int compare_vsi_off(const void *_a, const void *_b)
 {
 	const struct btf_var_secinfo *a = _a;
@@ -1165,16 +1294,9 @@ done:
 	return err;
 }
 
-#define BTF_DEDUP_TABLE_DEFAULT_SIZE (1 << 14)
-#define BTF_DEDUP_TABLE_MAX_SIZE_LOG 31
 #define BTF_UNPROCESSED_ID ((__u32)-1)
 #define BTF_IN_PROGRESS_ID ((__u32)-2)
 
-struct btf_dedup_node {
-	struct btf_dedup_node *next;
-	__u32 type_id;
-};
-
 struct btf_dedup {
 	/* .BTF section to be deduped in-place */
 	struct btf *btf;
@@ -1190,7 +1312,7 @@ struct btf_dedup {
 	 * candidates, which is fine because we rely on subsequent
 	 * btf_xxx_equal() checks to authoritatively verify type equality.
 	 */
-	struct btf_dedup_node **dedup_table;
+	struct hashmap *dedup_table;
 	/* Canonical types map */
 	__u32 *map;
 	/* Hypothetical mapping, used during type graph equivalence checks */
@@ -1215,30 +1337,18 @@ struct btf_str_ptrs {
 	__u32 cap;
 };
 
-static inline __u32 hash_combine(__u32 h, __u32 value)
+static long hash_combine(long h, long value)
 {
-/* 2^31 + 2^29 - 2^25 + 2^22 - 2^19 - 2^16 + 1 */
-#define GOLDEN_RATIO_PRIME 0x9e370001UL
-	return h * 37 + value * GOLDEN_RATIO_PRIME;
-#undef GOLDEN_RATIO_PRIME
+	return h * 31 + value;
 }
 
-#define for_each_dedup_cand(d, hash, node) \
-	for (node = d->dedup_table[hash & (d->opts.dedup_table_size - 1)]; \
-	     node;							   \
-	     node = node->next)
+#define for_each_dedup_cand(d, node, hash) \
+	hashmap__for_each_key_entry(d->dedup_table, node, (void *)hash)
 
-static int btf_dedup_table_add(struct btf_dedup *d, __u32 hash, __u32 type_id)
+static int btf_dedup_table_add(struct btf_dedup *d, long hash, __u32 type_id)
 {
-	struct btf_dedup_node *node = malloc(sizeof(struct btf_dedup_node));
-	int bucket = hash & (d->opts.dedup_table_size - 1);
-
-	if (!node)
-		return -ENOMEM;
-	node->type_id = type_id;
-	node->next = d->dedup_table[bucket];
-	d->dedup_table[bucket] = node;
-	return 0;
+	return hashmap__append(d->dedup_table,
+			       (void *)hash, (void *)(long)type_id);
 }
 
 static int btf_dedup_hypot_map_add(struct btf_dedup *d,
@@ -1267,36 +1377,10 @@ static void btf_dedup_clear_hypot_map(struct btf_dedup *d)
 	d->hypot_cnt = 0;
 }
 
-static void btf_dedup_table_free(struct btf_dedup *d)
-{
-	struct btf_dedup_node *head, *tmp;
-	int i;
-
-	if (!d->dedup_table)
-		return;
-
-	for (i = 0; i < d->opts.dedup_table_size; i++) {
-		while (d->dedup_table[i]) {
-			tmp = d->dedup_table[i];
-			d->dedup_table[i] = tmp->next;
-			free(tmp);
-		}
-
-		head = d->dedup_table[i];
-		while (head) {
-			tmp = head;
-			head = head->next;
-			free(tmp);
-		}
-	}
-
-	free(d->dedup_table);
-	d->dedup_table = NULL;
-}
-
 static void btf_dedup_free(struct btf_dedup *d)
 {
-	btf_dedup_table_free(d);
+	hashmap__free(d->dedup_table);
+	d->dedup_table = NULL;
 
 	free(d->map);
 	d->map = NULL;
@@ -1310,40 +1394,43 @@ static void btf_dedup_free(struct btf_dedup *d)
 	free(d);
 }
 
-/* Find closest power of two >= to size, capped at 2^max_size_log */
-static __u32 roundup_pow2_max(__u32 size, int max_size_log)
+static size_t btf_dedup_identity_hash_fn(const void *key, void *ctx)
 {
-	int i;
+	return (size_t)key;
+}
 
-	for (i = 0; i < max_size_log  && (1U << i) < size;  i++)
-		;
-	return 1U << i;
+static size_t btf_dedup_collision_hash_fn(const void *key, void *ctx)
+{
+	return 0;
 }
 
+static bool btf_dedup_equal_fn(const void *k1, const void *k2, void *ctx)
+{
+	return k1 == k2;
+}
 
 static struct btf_dedup *btf_dedup_new(struct btf *btf, struct btf_ext *btf_ext,
 				       const struct btf_dedup_opts *opts)
 {
 	struct btf_dedup *d = calloc(1, sizeof(struct btf_dedup));
+	hashmap_hash_fn hash_fn = btf_dedup_identity_hash_fn;
 	int i, err = 0;
-	__u32 sz;
 
 	if (!d)
 		return ERR_PTR(-ENOMEM);
 
 	d->opts.dont_resolve_fwds = opts && opts->dont_resolve_fwds;
-	sz = opts && opts->dedup_table_size ? opts->dedup_table_size
-					    : BTF_DEDUP_TABLE_DEFAULT_SIZE;
-	sz = roundup_pow2_max(sz, BTF_DEDUP_TABLE_MAX_SIZE_LOG);
-	d->opts.dedup_table_size = sz;
+	/* dedup_table_size is now used only to force collisions in tests */
+	if (opts && opts->dedup_table_size == 1)
+		hash_fn = btf_dedup_collision_hash_fn;
 
 	d->btf = btf;
 	d->btf_ext = btf_ext;
 
-	d->dedup_table = calloc(d->opts.dedup_table_size,
-				sizeof(struct btf_dedup_node *));
-	if (!d->dedup_table) {
-		err = -ENOMEM;
+	d->dedup_table = hashmap__new(hash_fn, btf_dedup_equal_fn, NULL);
+	if (IS_ERR(d->dedup_table)) {
+		err = PTR_ERR(d->dedup_table);
+		d->dedup_table = NULL;
 		goto done;
 	}
 
@@ -1662,9 +1749,9 @@ done:
 	return err;
 }
 
-static __u32 btf_hash_common(struct btf_type *t)
+static long btf_hash_common(struct btf_type *t)
 {
-	__u32 h;
+	long h;
 
 	h = hash_combine(0, t->name_off);
 	h = hash_combine(h, t->info);
@@ -1680,10 +1767,10 @@ static bool btf_equal_common(struct btf_type *t1, struct btf_type *t2)
 }
 
 /* Calculate type signature hash of INT. */
-static __u32 btf_hash_int(struct btf_type *t)
+static long btf_hash_int(struct btf_type *t)
 {
 	__u32 info = *(__u32 *)(t + 1);
-	__u32 h;
+	long h;
 
 	h = btf_hash_common(t);
 	h = hash_combine(h, info);
@@ -1703,9 +1790,9 @@ static bool btf_equal_int(struct btf_type *t1, struct btf_type *t2)
 }
 
 /* Calculate type signature hash of ENUM. */
-static __u32 btf_hash_enum(struct btf_type *t)
+static long btf_hash_enum(struct btf_type *t)
 {
-	__u32 h;
+	long h;
 
 	/* don't hash vlen and enum members to support enum fwd resolving */
 	h = hash_combine(0, t->name_off);
@@ -1757,11 +1844,11 @@ static bool btf_compat_enum(struct btf_type *t1, struct btf_type *t2)
  * as referenced type IDs equivalence is established separately during type
  * graph equivalence check algorithm.
  */
-static __u32 btf_hash_struct(struct btf_type *t)
+static long btf_hash_struct(struct btf_type *t)
 {
 	struct btf_member *member = (struct btf_member *)(t + 1);
 	__u32 vlen = BTF_INFO_VLEN(t->info);
-	__u32 h = btf_hash_common(t);
+	long h = btf_hash_common(t);
 	int i;
 
 	for (i = 0; i < vlen; i++) {
@@ -1804,10 +1891,10 @@ static bool btf_shallow_equal_struct(struct btf_type *t1, struct btf_type *t2)
  * under assumption that they were already resolved to canonical type IDs and
  * are not going to change.
  */
-static __u32 btf_hash_array(struct btf_type *t)
+static long btf_hash_array(struct btf_type *t)
 {
 	struct btf_array *info = (struct btf_array *)(t + 1);
-	__u32 h = btf_hash_common(t);
+	long h = btf_hash_common(t);
 
 	h = hash_combine(h, info->type);
 	h = hash_combine(h, info->index_type);
@@ -1858,11 +1945,11 @@ static bool btf_compat_array(struct btf_type *t1, struct btf_type *t2)
  * under assumption that they were already resolved to canonical type IDs and
  * are not going to change.
  */
-static inline __u32 btf_hash_fnproto(struct btf_type *t)
+static long btf_hash_fnproto(struct btf_type *t)
 {
 	struct btf_param *member = (struct btf_param *)(t + 1);
 	__u16 vlen = BTF_INFO_VLEN(t->info);
-	__u32 h = btf_hash_common(t);
+	long h = btf_hash_common(t);
 	int i;
 
 	for (i = 0; i < vlen; i++) {
@@ -1880,7 +1967,7 @@ static inline __u32 btf_hash_fnproto(struct btf_type *t)
  * This function is called during reference types deduplication to compare
  * FUNC_PROTO to potential canonical representative.
  */
-static inline bool btf_equal_fnproto(struct btf_type *t1, struct btf_type *t2)
+static bool btf_equal_fnproto(struct btf_type *t1, struct btf_type *t2)
 {
 	struct btf_param *m1, *m2;
 	__u16 vlen;
@@ -1906,7 +1993,7 @@ static inline bool btf_equal_fnproto(struct btf_type *t1, struct btf_type *t2)
  * IDs. This check is performed during type graph equivalence check and
  * referenced types equivalence is checked separately.
  */
-static inline bool btf_compat_fnproto(struct btf_type *t1, struct btf_type *t2)
+static bool btf_compat_fnproto(struct btf_type *t1, struct btf_type *t2)
 {
 	struct btf_param *m1, *m2;
 	__u16 vlen;
@@ -1937,11 +2024,12 @@ static inline bool btf_compat_fnproto(struct btf_type *t1, struct btf_type *t2)
 static int btf_dedup_prim_type(struct btf_dedup *d, __u32 type_id)
 {
 	struct btf_type *t = d->btf->types[type_id];
+	struct hashmap_entry *hash_entry;
 	struct btf_type *cand;
-	struct btf_dedup_node *cand_node;
 	/* if we don't find equivalent type, then we are canonical */
 	__u32 new_id = type_id;
-	__u32 h;
+	__u32 cand_id;
+	long h;
 
 	switch (BTF_INFO_KIND(t->info)) {
 	case BTF_KIND_CONST:
@@ -1960,10 +2048,11 @@ static int btf_dedup_prim_type(struct btf_dedup *d, __u32 type_id)
 
 	case BTF_KIND_INT:
 		h = btf_hash_int(t);
-		for_each_dedup_cand(d, h, cand_node) {
-			cand = d->btf->types[cand_node->type_id];
+		for_each_dedup_cand(d, hash_entry, h) {
+			cand_id = (__u32)(long)hash_entry->value;
+			cand = d->btf->types[cand_id];
 			if (btf_equal_int(t, cand)) {
-				new_id = cand_node->type_id;
+				new_id = cand_id;
 				break;
 			}
 		}
@@ -1971,10 +2060,11 @@ static int btf_dedup_prim_type(struct btf_dedup *d, __u32 type_id)
 
 	case BTF_KIND_ENUM:
 		h = btf_hash_enum(t);
-		for_each_dedup_cand(d, h, cand_node) {
-			cand = d->btf->types[cand_node->type_id];
+		for_each_dedup_cand(d, hash_entry, h) {
+			cand_id = (__u32)(long)hash_entry->value;
+			cand = d->btf->types[cand_id];
 			if (btf_equal_enum(t, cand)) {
-				new_id = cand_node->type_id;
+				new_id = cand_id;
 				break;
 			}
 			if (d->opts.dont_resolve_fwds)
@@ -1982,21 +2072,22 @@ static int btf_dedup_prim_type(struct btf_dedup *d, __u32 type_id)
 			if (btf_compat_enum(t, cand)) {
 				if (btf_is_enum_fwd(t)) {
 					/* resolve fwd to full enum */
-					new_id = cand_node->type_id;
+					new_id = cand_id;
 					break;
 				}
 				/* resolve canonical enum fwd to full enum */
-				d->map[cand_node->type_id] = type_id;
+				d->map[cand_id] = type_id;
 			}
 		}
 		break;
 
 	case BTF_KIND_FWD:
 		h = btf_hash_common(t);
-		for_each_dedup_cand(d, h, cand_node) {
-			cand = d->btf->types[cand_node->type_id];
+		for_each_dedup_cand(d, hash_entry, h) {
+			cand_id = (__u32)(long)hash_entry->value;
+			cand = d->btf->types[cand_id];
 			if (btf_equal_common(t, cand)) {
-				new_id = cand_node->type_id;
+				new_id = cand_id;
 				break;
 			}
 		}
@@ -2397,12 +2488,12 @@ static void btf_dedup_merge_hypot_map(struct btf_dedup *d)
  */
 static int btf_dedup_struct_type(struct btf_dedup *d, __u32 type_id)
 {
-	struct btf_dedup_node *cand_node;
 	struct btf_type *cand_type, *t;
+	struct hashmap_entry *hash_entry;
 	/* if we don't find equivalent type, then we are canonical */
 	__u32 new_id = type_id;
 	__u16 kind;
-	__u32 h;
+	long h;
 
 	/* already deduped or is in process of deduping (loop detected) */
 	if (d->map[type_id] <= BTF_MAX_NR_TYPES)
@@ -2415,7 +2506,8 @@ static int btf_dedup_struct_type(struct btf_dedup *d, __u32 type_id)
 		return 0;
 
 	h = btf_hash_struct(t);
-	for_each_dedup_cand(d, h, cand_node) {
+	for_each_dedup_cand(d, hash_entry, h) {
+		__u32 cand_id = (__u32)(long)hash_entry->value;
 		int eq;
 
 		/*
@@ -2428,17 +2520,17 @@ static int btf_dedup_struct_type(struct btf_dedup *d, __u32 type_id)
 		 * creating a loop (FWD -> STRUCT and STRUCT -> FWD), because
 		 * FWD and compatible STRUCT/UNION are considered equivalent.
 		 */
-		cand_type = d->btf->types[cand_node->type_id];
+		cand_type = d->btf->types[cand_id];
 		if (!btf_shallow_equal_struct(t, cand_type))
 			continue;
 
 		btf_dedup_clear_hypot_map(d);
-		eq = btf_dedup_is_equiv(d, type_id, cand_node->type_id);
+		eq = btf_dedup_is_equiv(d, type_id, cand_id);
 		if (eq < 0)
 			return eq;
 		if (!eq)
 			continue;
-		new_id = cand_node->type_id;
+		new_id = cand_id;
 		btf_dedup_merge_hypot_map(d);
 		break;
 	}
@@ -2488,12 +2580,12 @@ static int btf_dedup_struct_types(struct btf_dedup *d)
  */
 static int btf_dedup_ref_type(struct btf_dedup *d, __u32 type_id)
 {
-	struct btf_dedup_node *cand_node;
+	struct hashmap_entry *hash_entry;
+	__u32 new_id = type_id, cand_id;
 	struct btf_type *t, *cand;
 	/* if we don't find equivalent type, then we are representative type */
-	__u32 new_id = type_id;
 	int ref_type_id;
-	__u32 h;
+	long h;
 
 	if (d->map[type_id] == BTF_IN_PROGRESS_ID)
 		return -ELOOP;
@@ -2516,10 +2608,11 @@ static int btf_dedup_ref_type(struct btf_dedup *d, __u32 type_id)
 		t->type = ref_type_id;
 
 		h = btf_hash_common(t);
-		for_each_dedup_cand(d, h, cand_node) {
-			cand = d->btf->types[cand_node->type_id];
+		for_each_dedup_cand(d, hash_entry, h) {
+			cand_id = (__u32)(long)hash_entry->value;
+			cand = d->btf->types[cand_id];
 			if (btf_equal_common(t, cand)) {
-				new_id = cand_node->type_id;
+				new_id = cand_id;
 				break;
 			}
 		}
@@ -2539,10 +2632,11 @@ static int btf_dedup_ref_type(struct btf_dedup *d, __u32 type_id)
 		info->index_type = ref_type_id;
 
 		h = btf_hash_array(t);
-		for_each_dedup_cand(d, h, cand_node) {
-			cand = d->btf->types[cand_node->type_id];
+		for_each_dedup_cand(d, hash_entry, h) {
+			cand_id = (__u32)(long)hash_entry->value;
+			cand = d->btf->types[cand_id];
 			if (btf_equal_array(t, cand)) {
-				new_id = cand_node->type_id;
+				new_id = cand_id;
 				break;
 			}
 		}
@@ -2570,10 +2664,11 @@ static int btf_dedup_ref_type(struct btf_dedup *d, __u32 type_id)
 		}
 
 		h = btf_hash_fnproto(t);
-		for_each_dedup_cand(d, h, cand_node) {
-			cand = d->btf->types[cand_node->type_id];
+		for_each_dedup_cand(d, hash_entry, h) {
+			cand_id = (__u32)(long)hash_entry->value;
+			cand = d->btf->types[cand_id];
 			if (btf_equal_fnproto(t, cand)) {
-				new_id = cand_node->type_id;
+				new_id = cand_id;
 				break;
 			}
 		}
@@ -2600,7 +2695,9 @@ static int btf_dedup_ref_types(struct btf_dedup *d)
 		if (err < 0)
 			return err;
 	}
-	btf_dedup_table_free(d);
+	/* we won't need d->dedup_table anymore */
+	hashmap__free(d->dedup_table);
+	d->dedup_table = NULL;
 	return 0;
 }
 
diff --git a/tools/lib/bpf/btf.h b/tools/lib/bpf/btf.h
index c7b399e81fce..ba4ffa831aa4 100644
--- a/tools/lib/bpf/btf.h
+++ b/tools/lib/bpf/btf.h
@@ -4,6 +4,7 @@
 #ifndef __LIBBPF_BTF_H
 #define __LIBBPF_BTF_H
 
+#include <stdarg.h>
 #include <linux/types.h>
 
 #ifdef __cplusplus
@@ -59,6 +60,8 @@ struct btf_ext_header {
 
 LIBBPF_API void btf__free(struct btf *btf);
 LIBBPF_API struct btf *btf__new(__u8 *data, __u32 size);
+LIBBPF_API struct btf *btf__parse_elf(const char *path,
+				      struct btf_ext **btf_ext);
 LIBBPF_API int btf__finalize_data(struct bpf_object *obj, struct btf *btf);
 LIBBPF_API int btf__load(struct btf *btf);
 LIBBPF_API __s32 btf__find_by_name(const struct btf *btf,
@@ -100,6 +103,22 @@ struct btf_dedup_opts {
 LIBBPF_API int btf__dedup(struct btf *btf, struct btf_ext *btf_ext,
 			  const struct btf_dedup_opts *opts);
 
+struct btf_dump;
+
+struct btf_dump_opts {
+	void *ctx;
+};
+
+typedef void (*btf_dump_printf_fn_t)(void *ctx, const char *fmt, va_list args);
+
+LIBBPF_API struct btf_dump *btf_dump__new(const struct btf *btf,
+					  const struct btf_ext *btf_ext,
+					  const struct btf_dump_opts *opts,
+					  btf_dump_printf_fn_t printf_fn);
+LIBBPF_API void btf_dump__free(struct btf_dump *d);
+
+LIBBPF_API int btf_dump__dump_type(struct btf_dump *d, __u32 id);
+
 #ifdef __cplusplus
 } /* extern "C" */
 #endif
diff --git a/tools/lib/bpf/btf_dump.c b/tools/lib/bpf/btf_dump.c
new file mode 100644
index 000000000000..4b22db77e2cc
--- /dev/null
+++ b/tools/lib/bpf/btf_dump.c
@@ -0,0 +1,1336 @@
+// SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
+
+/*
+ * BTF-to-C type converter.
+ *
+ * Copyright (c) 2019 Facebook
+ */
+
+#include <stdbool.h>
+#include <stddef.h>
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+#include <linux/err.h>
+#include <linux/btf.h>
+#include "btf.h"
+#include "hashmap.h"
+#include "libbpf.h"
+#include "libbpf_internal.h"
+
+#define min(x, y) ((x) < (y) ? (x) : (y))
+#define max(x, y) ((x) < (y) ? (y) : (x))
+
+static const char PREFIXES[] = "\t\t\t\t\t\t\t\t\t\t\t\t\t";
+static const size_t PREFIX_CNT = sizeof(PREFIXES) - 1;
+
+static const char *pfx(int lvl)
+{
+	return lvl >= PREFIX_CNT ? PREFIXES : &PREFIXES[PREFIX_CNT - lvl];
+}
+
+enum btf_dump_type_order_state {
+	NOT_ORDERED,
+	ORDERING,
+	ORDERED,
+};
+
+enum btf_dump_type_emit_state {
+	NOT_EMITTED,
+	EMITTING,
+	EMITTED,
+};
+
+/* per-type auxiliary state */
+struct btf_dump_type_aux_state {
+	/* topological sorting state */
+	enum btf_dump_type_order_state order_state: 2;
+	/* emitting state used to determine the need for forward declaration */
+	enum btf_dump_type_emit_state emit_state: 2;
+	/* whether forward declaration was already emitted */
+	__u8 fwd_emitted: 1;
+	/* whether unique non-duplicate name was already assigned */
+	__u8 name_resolved: 1;
+};
+
+struct btf_dump {
+	const struct btf *btf;
+	const struct btf_ext *btf_ext;
+	btf_dump_printf_fn_t printf_fn;
+	struct btf_dump_opts opts;
+
+	/* per-type auxiliary state */
+	struct btf_dump_type_aux_state *type_states;
+	/* per-type optional cached unique name, must be freed, if present */
+	const char **cached_names;
+
+	/* topo-sorted list of dependent type definitions */
+	__u32 *emit_queue;
+	int emit_queue_cap;
+	int emit_queue_cnt;
+
+	/*
+	 * stack of type declarations (e.g., chain of modifiers, arrays,
+	 * funcs, etc)
+	 */
+	__u32 *decl_stack;
+	int decl_stack_cap;
+	int decl_stack_cnt;
+
+	/* maps struct/union/enum name to a number of name occurrences */
+	struct hashmap *type_names;
+	/*
+	 * maps typedef identifiers and enum value names to a number of such
+	 * name occurrences
+	 */
+	struct hashmap *ident_names;
+};
+
+static size_t str_hash_fn(const void *key, void *ctx)
+{
+	const char *s = key;
+	size_t h = 0;
+
+	while (*s) {
+		h = h * 31 + *s;
+		s++;
+	}
+	return h;
+}
+
+static bool str_equal_fn(const void *a, const void *b, void *ctx)
+{
+	return strcmp(a, b) == 0;
+}
+
+static __u16 btf_kind_of(const struct btf_type *t)
+{
+	return BTF_INFO_KIND(t->info);
+}
+
+static __u16 btf_vlen_of(const struct btf_type *t)
+{
+	return BTF_INFO_VLEN(t->info);
+}
+
+static bool btf_kflag_of(const struct btf_type *t)
+{
+	return BTF_INFO_KFLAG(t->info);
+}
+
+static const char *btf_name_of(const struct btf_dump *d, __u32 name_off)
+{
+	return btf__name_by_offset(d->btf, name_off);
+}
+
+static void btf_dump_printf(const struct btf_dump *d, const char *fmt, ...)
+{
+	va_list args;
+
+	va_start(args, fmt);
+	d->printf_fn(d->opts.ctx, fmt, args);
+	va_end(args);
+}
+
+struct btf_dump *btf_dump__new(const struct btf *btf,
+			       const struct btf_ext *btf_ext,
+			       const struct btf_dump_opts *opts,
+			       btf_dump_printf_fn_t printf_fn)
+{
+	struct btf_dump *d;
+	int err;
+
+	d = calloc(1, sizeof(struct btf_dump));
+	if (!d)
+		return ERR_PTR(-ENOMEM);
+
+	d->btf = btf;
+	d->btf_ext = btf_ext;
+	d->printf_fn = printf_fn;
+	d->opts.ctx = opts ? opts->ctx : NULL;
+
+	d->type_names = hashmap__new(str_hash_fn, str_equal_fn, NULL);
+	if (IS_ERR(d->type_names)) {
+		err = PTR_ERR(d->type_names);
+		d->type_names = NULL;
+		btf_dump__free(d);
+		return ERR_PTR(err);
+	}
+	d->ident_names = hashmap__new(str_hash_fn, str_equal_fn, NULL);
+	if (IS_ERR(d->ident_names)) {
+		err = PTR_ERR(d->ident_names);
+		d->ident_names = NULL;
+		btf_dump__free(d);
+		return ERR_PTR(err);
+	}
+
+	return d;
+}
+
+void btf_dump__free(struct btf_dump *d)
+{
+	int i, cnt;
+
+	if (!d)
+		return;
+
+	free(d->type_states);
+	if (d->cached_names) {
+		/* any set cached name is owned by us and should be freed */
+		for (i = 0, cnt = btf__get_nr_types(d->btf); i <= cnt; i++) {
+			if (d->cached_names[i])
+				free((void *)d->cached_names[i]);
+		}
+	}
+	free(d->cached_names);
+	free(d->emit_queue);
+	free(d->decl_stack);
+	hashmap__free(d->type_names);
+	hashmap__free(d->ident_names);
+
+	free(d);
+}
+
+static int btf_dump_order_type(struct btf_dump *d, __u32 id, bool through_ptr);
+static void btf_dump_emit_type(struct btf_dump *d, __u32 id, __u32 cont_id);
+
+/*
+ * Dump BTF type in a compilable C syntax, including all the necessary
+ * dependent types, necessary for compilation. If some of the dependent types
+ * were already emitted as part of previous btf_dump__dump_type() invocation
+ * for another type, they won't be emitted again. This API allows callers to
+ * filter out BTF types according to user-defined criterias and emitted only
+ * minimal subset of types, necessary to compile everything. Full struct/union
+ * definitions will still be emitted, even if the only usage is through
+ * pointer and could be satisfied with just a forward declaration.
+ *
+ * Dumping is done in two high-level passes:
+ *   1. Topologically sort type definitions to satisfy C rules of compilation.
+ *   2. Emit type definitions in C syntax.
+ *
+ * Returns 0 on success; <0, otherwise.
+ */
+int btf_dump__dump_type(struct btf_dump *d, __u32 id)
+{
+	int err, i;
+
+	if (id > btf__get_nr_types(d->btf))
+		return -EINVAL;
+
+	/* type states are lazily allocated, as they might not be needed */
+	if (!d->type_states) {
+		d->type_states = calloc(1 + btf__get_nr_types(d->btf),
+					sizeof(d->type_states[0]));
+		if (!d->type_states)
+			return -ENOMEM;
+		d->cached_names = calloc(1 + btf__get_nr_types(d->btf),
+					 sizeof(d->cached_names[0]));
+		if (!d->cached_names)
+			return -ENOMEM;
+
+		/* VOID is special */
+		d->type_states[0].order_state = ORDERED;
+		d->type_states[0].emit_state = EMITTED;
+	}
+
+	d->emit_queue_cnt = 0;
+	err = btf_dump_order_type(d, id, false);
+	if (err < 0)
+		return err;
+
+	for (i = 0; i < d->emit_queue_cnt; i++)
+		btf_dump_emit_type(d, d->emit_queue[i], 0 /*top-level*/);
+
+	return 0;
+}
+
+static int btf_dump_add_emit_queue_id(struct btf_dump *d, __u32 id)
+{
+	__u32 *new_queue;
+	size_t new_cap;
+
+	if (d->emit_queue_cnt >= d->emit_queue_cap) {
+		new_cap = max(16, d->emit_queue_cap * 3 / 2);
+		new_queue = realloc(d->emit_queue,
+				    new_cap * sizeof(new_queue[0]));
+		if (!new_queue)
+			return -ENOMEM;
+		d->emit_queue = new_queue;
+		d->emit_queue_cap = new_cap;
+	}
+
+	d->emit_queue[d->emit_queue_cnt++] = id;
+	return 0;
+}
+
+/*
+ * Determine order of emitting dependent types and specified type to satisfy
+ * C compilation rules.  This is done through topological sorting with an
+ * additional complication which comes from C rules. The main idea for C is
+ * that if some type is "embedded" into a struct/union, it's size needs to be
+ * known at the time of definition of containing type. E.g., for:
+ *
+ *	struct A {};
+ *	struct B { struct A x; }
+ *
+ * struct A *HAS* to be defined before struct B, because it's "embedded",
+ * i.e., it is part of struct B layout. But in the following case:
+ *
+ *	struct A;
+ *	struct B { struct A *x; }
+ *	struct A {};
+ *
+ * it's enough to just have a forward declaration of struct A at the time of
+ * struct B definition, as struct B has a pointer to struct A, so the size of
+ * field x is known without knowing struct A size: it's sizeof(void *).
+ *
+ * Unfortunately, there are some trickier cases we need to handle, e.g.:
+ *
+ *	struct A {}; // if this was forward-declaration: compilation error
+ *	struct B {
+ *		struct { // anonymous struct
+ *			struct A y;
+ *		} *x;
+ *	};
+ *
+ * In this case, struct B's field x is a pointer, so it's size is known
+ * regardless of the size of (anonymous) struct it points to. But because this
+ * struct is anonymous and thus defined inline inside struct B, *and* it
+ * embeds struct A, compiler requires full definition of struct A to be known
+ * before struct B can be defined. This creates a transitive dependency
+ * between struct A and struct B. If struct A was forward-declared before
+ * struct B definition and fully defined after struct B definition, that would
+ * trigger compilation error.
+ *
+ * All this means that while we are doing topological sorting on BTF type
+ * graph, we need to determine relationships between different types (graph
+ * nodes):
+ *   - weak link (relationship) between X and Y, if Y *CAN* be
+ *   forward-declared at the point of X definition;
+ *   - strong link, if Y *HAS* to be fully-defined before X can be defined.
+ *
+ * The rule is as follows. Given a chain of BTF types from X to Y, if there is
+ * BTF_KIND_PTR type in the chain and at least one non-anonymous type
+ * Z (excluding X, including Y), then link is weak. Otherwise, it's strong.
+ * Weak/strong relationship is determined recursively during DFS traversal and
+ * is returned as a result from btf_dump_order_type().
+ *
+ * btf_dump_order_type() is trying to avoid unnecessary forward declarations,
+ * but it is not guaranteeing that no extraneous forward declarations will be
+ * emitted.
+ *
+ * To avoid extra work, algorithm marks some of BTF types as ORDERED, when
+ * it's done with them, but not for all (e.g., VOLATILE, CONST, RESTRICT,
+ * ARRAY, FUNC_PROTO), as weak/strong semantics for those depends on the
+ * entire graph path, so depending where from one came to that BTF type, it
+ * might cause weak or strong ordering. For types like STRUCT/UNION/INT/ENUM,
+ * once they are processed, there is no need to do it again, so they are
+ * marked as ORDERED. We can mark PTR as ORDERED as well, as it semi-forces
+ * weak link, unless subsequent referenced STRUCT/UNION/ENUM is anonymous. But
+ * in any case, once those are processed, no need to do it again, as the
+ * result won't change.
+ *
+ * Returns:
+ *   - 1, if type is part of strong link (so there is strong topological
+ *   ordering requirements);
+ *   - 0, if type is part of weak link (so can be satisfied through forward
+ *   declaration);
+ *   - <0, on error (e.g., unsatisfiable type loop detected).
+ */
+static int btf_dump_order_type(struct btf_dump *d, __u32 id, bool through_ptr)
+{
+	/*
+	 * Order state is used to detect strong link cycles, but only for BTF
+	 * kinds that are or could be an independent definition (i.e.,
+	 * stand-alone fwd decl, enum, typedef, struct, union). Ptrs, arrays,
+	 * func_protos, modifiers are just means to get to these definitions.
+	 * Int/void don't need definitions, they are assumed to be always
+	 * properly defined.  We also ignore datasec, var, and funcs for now.
+	 * So for all non-defining kinds, we never even set ordering state,
+	 * for defining kinds we set ORDERING and subsequently ORDERED if it
+	 * forms a strong link.
+	 */
+	struct btf_dump_type_aux_state *tstate = &d->type_states[id];
+	const struct btf_type *t;
+	__u16 kind, vlen;
+	int err, i;
+
+	/* return true, letting typedefs know that it's ok to be emitted */
+	if (tstate->order_state == ORDERED)
+		return 1;
+
+	t = btf__type_by_id(d->btf, id);
+	kind = btf_kind_of(t);
+
+	if (tstate->order_state == ORDERING) {
+		/* type loop, but resolvable through fwd declaration */
+		if ((kind == BTF_KIND_STRUCT || kind == BTF_KIND_UNION) &&
+		    through_ptr && t->name_off != 0)
+			return 0;
+		pr_warning("unsatisfiable type cycle, id:[%u]\n", id);
+		return -ELOOP;
+	}
+
+	switch (kind) {
+	case BTF_KIND_INT:
+		tstate->order_state = ORDERED;
+		return 0;
+
+	case BTF_KIND_PTR:
+		err = btf_dump_order_type(d, t->type, true);
+		tstate->order_state = ORDERED;
+		return err;
+
+	case BTF_KIND_ARRAY: {
+		const struct btf_array *a = (void *)(t + 1);
+
+		return btf_dump_order_type(d, a->type, through_ptr);
+	}
+	case BTF_KIND_STRUCT:
+	case BTF_KIND_UNION: {
+		const struct btf_member *m = (void *)(t + 1);
+		/*
+		 * struct/union is part of strong link, only if it's embedded
+		 * (so no ptr in a path) or it's anonymous (so has to be
+		 * defined inline, even if declared through ptr)
+		 */
+		if (through_ptr && t->name_off != 0)
+			return 0;
+
+		tstate->order_state = ORDERING;
+
+		vlen = btf_vlen_of(t);
+		for (i = 0; i < vlen; i++, m++) {
+			err = btf_dump_order_type(d, m->type, false);
+			if (err < 0)
+				return err;
+		}
+
+		if (t->name_off != 0) {
+			err = btf_dump_add_emit_queue_id(d, id);
+			if (err < 0)
+				return err;
+		}
+
+		tstate->order_state = ORDERED;
+		return 1;
+	}
+	case BTF_KIND_ENUM:
+	case BTF_KIND_FWD:
+		if (t->name_off != 0) {
+			err = btf_dump_add_emit_queue_id(d, id);
+			if (err)
+				return err;
+		}
+		tstate->order_state = ORDERED;
+		return 1;
+
+	case BTF_KIND_TYPEDEF: {
+		int is_strong;
+
+		is_strong = btf_dump_order_type(d, t->type, through_ptr);
+		if (is_strong < 0)
+			return is_strong;
+
+		/* typedef is similar to struct/union w.r.t. fwd-decls */
+		if (through_ptr && !is_strong)
+			return 0;
+
+		/* typedef is always a named definition */
+		err = btf_dump_add_emit_queue_id(d, id);
+		if (err)
+			return err;
+
+		d->type_states[id].order_state = ORDERED;
+		return 1;
+	}
+	case BTF_KIND_VOLATILE:
+	case BTF_KIND_CONST:
+	case BTF_KIND_RESTRICT:
+		return btf_dump_order_type(d, t->type, through_ptr);
+
+	case BTF_KIND_FUNC_PROTO: {
+		const struct btf_param *p = (void *)(t + 1);
+		bool is_strong;
+
+		err = btf_dump_order_type(d, t->type, through_ptr);
+		if (err < 0)
+			return err;
+		is_strong = err > 0;
+
+		vlen = btf_vlen_of(t);
+		for (i = 0; i < vlen; i++, p++) {
+			err = btf_dump_order_type(d, p->type, through_ptr);
+			if (err < 0)
+				return err;
+			if (err > 0)
+				is_strong = true;
+		}
+		return is_strong;
+	}
+	case BTF_KIND_FUNC:
+	case BTF_KIND_VAR:
+	case BTF_KIND_DATASEC:
+		d->type_states[id].order_state = ORDERED;
+		return 0;
+
+	default:
+		return -EINVAL;
+	}
+}
+
+static void btf_dump_emit_struct_fwd(struct btf_dump *d, __u32 id,
+				     const struct btf_type *t);
+static void btf_dump_emit_struct_def(struct btf_dump *d, __u32 id,
+				     const struct btf_type *t, int lvl);
+
+static void btf_dump_emit_enum_fwd(struct btf_dump *d, __u32 id,
+				   const struct btf_type *t);
+static void btf_dump_emit_enum_def(struct btf_dump *d, __u32 id,
+				   const struct btf_type *t, int lvl);
+
+static void btf_dump_emit_fwd_def(struct btf_dump *d, __u32 id,
+				  const struct btf_type *t);
+
+static void btf_dump_emit_typedef_def(struct btf_dump *d, __u32 id,
+				      const struct btf_type *t, int lvl);
+
+/* a local view into a shared stack */
+struct id_stack {
+	const __u32 *ids;
+	int cnt;
+};
+
+static void btf_dump_emit_type_decl(struct btf_dump *d, __u32 id,
+				    const char *fname, int lvl);
+static void btf_dump_emit_type_chain(struct btf_dump *d,
+				     struct id_stack *decl_stack,
+				     const char *fname, int lvl);
+
+static const char *btf_dump_type_name(struct btf_dump *d, __u32 id);
+static const char *btf_dump_ident_name(struct btf_dump *d, __u32 id);
+static size_t btf_dump_name_dups(struct btf_dump *d, struct hashmap *name_map,
+				 const char *orig_name);
+
+static bool btf_dump_is_blacklisted(struct btf_dump *d, __u32 id)
+{
+	const struct btf_type *t = btf__type_by_id(d->btf, id);
+
+	/* __builtin_va_list is a compiler built-in, which causes compilation
+	 * errors, when compiling w/ different compiler, then used to compile
+	 * original code (e.g., GCC to compile kernel, Clang to use generated
+	 * C header from BTF). As it is built-in, it should be already defined
+	 * properly internally in compiler.
+	 */
+	if (t->name_off == 0)
+		return false;
+	return strcmp(btf_name_of(d, t->name_off), "__builtin_va_list") == 0;
+}
+
+/*
+ * Emit C-syntax definitions of types from chains of BTF types.
+ *
+ * High-level handling of determining necessary forward declarations are handled
+ * by btf_dump_emit_type() itself, but all nitty-gritty details of emitting type
+ * declarations/definitions in C syntax  are handled by a combo of
+ * btf_dump_emit_type_decl()/btf_dump_emit_type_chain() w/ delegation to
+ * corresponding btf_dump_emit_*_{def,fwd}() functions.
+ *
+ * We also keep track of "containing struct/union type ID" to determine when
+ * we reference it from inside and thus can avoid emitting unnecessary forward
+ * declaration.
+ *
+ * This algorithm is designed in such a way, that even if some error occurs
+ * (either technical, e.g., out of memory, or logical, i.e., malformed BTF
+ * that doesn't comply to C rules completely), algorithm will try to proceed
+ * and produce as much meaningful output as possible.
+ */
+static void btf_dump_emit_type(struct btf_dump *d, __u32 id, __u32 cont_id)
+{
+	struct btf_dump_type_aux_state *tstate = &d->type_states[id];
+	bool top_level_def = cont_id == 0;
+	const struct btf_type *t;
+	__u16 kind;
+
+	if (tstate->emit_state == EMITTED)
+		return;
+
+	t = btf__type_by_id(d->btf, id);
+	kind = btf_kind_of(t);
+
+	if (top_level_def && t->name_off == 0) {
+		pr_warning("unexpected nameless definition, id:[%u]\n", id);
+		return;
+	}
+
+	if (tstate->emit_state == EMITTING) {
+		if (tstate->fwd_emitted)
+			return;
+
+		switch (kind) {
+		case BTF_KIND_STRUCT:
+		case BTF_KIND_UNION:
+			/*
+			 * if we are referencing a struct/union that we are
+			 * part of - then no need for fwd declaration
+			 */
+			if (id == cont_id)
+				return;
+			if (t->name_off == 0) {
+				pr_warning("anonymous struct/union loop, id:[%u]\n",
+					   id);
+				return;
+			}
+			btf_dump_emit_struct_fwd(d, id, t);
+			btf_dump_printf(d, ";\n\n");
+			tstate->fwd_emitted = 1;
+			break;
+		case BTF_KIND_TYPEDEF:
+			/*
+			 * for typedef fwd_emitted means typedef definition
+			 * was emitted, but it can be used only for "weak"
+			 * references through pointer only, not for embedding
+			 */
+			if (!btf_dump_is_blacklisted(d, id)) {
+				btf_dump_emit_typedef_def(d, id, t, 0);
+				btf_dump_printf(d, ";\n\n");
+			};
+			tstate->fwd_emitted = 1;
+			break;
+		default:
+			break;
+		}
+
+		return;
+	}
+
+	switch (kind) {
+	case BTF_KIND_INT:
+		tstate->emit_state = EMITTED;
+		break;
+	case BTF_KIND_ENUM:
+		if (top_level_def) {
+			btf_dump_emit_enum_def(d, id, t, 0);
+			btf_dump_printf(d, ";\n\n");
+		}
+		tstate->emit_state = EMITTED;
+		break;
+	case BTF_KIND_PTR:
+	case BTF_KIND_VOLATILE:
+	case BTF_KIND_CONST:
+	case BTF_KIND_RESTRICT:
+		btf_dump_emit_type(d, t->type, cont_id);
+		break;
+	case BTF_KIND_ARRAY: {
+		const struct btf_array *a = (void *)(t + 1);
+
+		btf_dump_emit_type(d, a->type, cont_id);
+		break;
+	}
+	case BTF_KIND_FWD:
+		btf_dump_emit_fwd_def(d, id, t);
+		btf_dump_printf(d, ";\n\n");
+		tstate->emit_state = EMITTED;
+		break;
+	case BTF_KIND_TYPEDEF:
+		tstate->emit_state = EMITTING;
+		btf_dump_emit_type(d, t->type, id);
+		/*
+		 * typedef can server as both definition and forward
+		 * declaration; at this stage someone depends on
+		 * typedef as a forward declaration (refers to it
+		 * through pointer), so unless we already did it,
+		 * emit typedef as a forward declaration
+		 */
+		if (!tstate->fwd_emitted && !btf_dump_is_blacklisted(d, id)) {
+			btf_dump_emit_typedef_def(d, id, t, 0);
+			btf_dump_printf(d, ";\n\n");
+		}
+		tstate->emit_state = EMITTED;
+		break;
+	case BTF_KIND_STRUCT:
+	case BTF_KIND_UNION:
+		tstate->emit_state = EMITTING;
+		/* if it's a top-level struct/union definition or struct/union
+		 * is anonymous, then in C we'll be emitting all fields and
+		 * their types (as opposed to just `struct X`), so we need to
+		 * make sure that all types, referenced from struct/union
+		 * members have necessary forward-declarations, where
+		 * applicable
+		 */
+		if (top_level_def || t->name_off == 0) {
+			const struct btf_member *m = (void *)(t + 1);
+			__u16 vlen = btf_vlen_of(t);
+			int i, new_cont_id;
+
+			new_cont_id = t->name_off == 0 ? cont_id : id;
+			for (i = 0; i < vlen; i++, m++)
+				btf_dump_emit_type(d, m->type, new_cont_id);
+		} else if (!tstate->fwd_emitted && id != cont_id) {
+			btf_dump_emit_struct_fwd(d, id, t);
+			btf_dump_printf(d, ";\n\n");
+			tstate->fwd_emitted = 1;
+		}
+
+		if (top_level_def) {
+			btf_dump_emit_struct_def(d, id, t, 0);
+			btf_dump_printf(d, ";\n\n");
+			tstate->emit_state = EMITTED;
+		} else {
+			tstate->emit_state = NOT_EMITTED;
+		}
+		break;
+	case BTF_KIND_FUNC_PROTO: {
+		const struct btf_param *p = (void *)(t + 1);
+		__u16 vlen = btf_vlen_of(t);
+		int i;
+
+		btf_dump_emit_type(d, t->type, cont_id);
+		for (i = 0; i < vlen; i++, p++)
+			btf_dump_emit_type(d, p->type, cont_id);
+
+		break;
+	}
+	default:
+		break;
+	}
+}
+
+static int btf_align_of(const struct btf *btf, __u32 id)
+{
+	const struct btf_type *t = btf__type_by_id(btf, id);
+	__u16 kind = btf_kind_of(t);
+
+	switch (kind) {
+	case BTF_KIND_INT:
+	case BTF_KIND_ENUM:
+		return min(sizeof(void *), t->size);
+	case BTF_KIND_PTR:
+		return sizeof(void *);
+	case BTF_KIND_TYPEDEF:
+	case BTF_KIND_VOLATILE:
+	case BTF_KIND_CONST:
+	case BTF_KIND_RESTRICT:
+		return btf_align_of(btf, t->type);
+	case BTF_KIND_ARRAY: {
+		const struct btf_array *a = (void *)(t + 1);
+
+		return btf_align_of(btf, a->type);
+	}
+	case BTF_KIND_STRUCT:
+	case BTF_KIND_UNION: {
+		const struct btf_member *m = (void *)(t + 1);
+		__u16 vlen = btf_vlen_of(t);
+		int i, align = 1;
+
+		for (i = 0; i < vlen; i++, m++)
+			align = max(align, btf_align_of(btf, m->type));
+
+		return align;
+	}
+	default:
+		pr_warning("unsupported BTF_KIND:%u\n", btf_kind_of(t));
+		return 1;
+	}
+}
+
+static bool btf_is_struct_packed(const struct btf *btf, __u32 id,
+				 const struct btf_type *t)
+{
+	const struct btf_member *m;
+	int align, i, bit_sz;
+	__u16 vlen;
+	bool kflag;
+
+	align = btf_align_of(btf, id);
+	/* size of a non-packed struct has to be a multiple of its alignment*/
+	if (t->size % align)
+		return true;
+
+	m = (void *)(t + 1);
+	kflag = btf_kflag_of(t);
+	vlen = btf_vlen_of(t);
+	/* all non-bitfield fields have to be naturally aligned */
+	for (i = 0; i < vlen; i++, m++) {
+		align = btf_align_of(btf, m->type);
+		bit_sz = kflag ? BTF_MEMBER_BITFIELD_SIZE(m->offset) : 0;
+		if (bit_sz == 0 && m->offset % (8 * align) != 0)
+			return true;
+	}
+
+	/*
+	 * if original struct was marked as packed, but its layout is
+	 * naturally aligned, we'll detect that it's not packed
+	 */
+	return false;
+}
+
+static int chip_away_bits(int total, int at_most)
+{
+	return total % at_most ? : at_most;
+}
+
+static void btf_dump_emit_bit_padding(const struct btf_dump *d,
+				      int cur_off, int m_off, int m_bit_sz,
+				      int align, int lvl)
+{
+	int off_diff = m_off - cur_off;
+	int ptr_bits = sizeof(void *) * 8;
+
+	if (off_diff <= 0)
+		/* no gap */
+		return;
+	if (m_bit_sz == 0 && off_diff < align * 8)
+		/* natural padding will take care of a gap */
+		return;
+
+	while (off_diff > 0) {
+		const char *pad_type;
+		int pad_bits;
+
+		if (ptr_bits > 32 && off_diff > 32) {
+			pad_type = "long";
+			pad_bits = chip_away_bits(off_diff, ptr_bits);
+		} else if (off_diff > 16) {
+			pad_type = "int";
+			pad_bits = chip_away_bits(off_diff, 32);
+		} else if (off_diff > 8) {
+			pad_type = "short";
+			pad_bits = chip_away_bits(off_diff, 16);
+		} else {
+			pad_type = "char";
+			pad_bits = chip_away_bits(off_diff, 8);
+		}
+		btf_dump_printf(d, "\n%s%s: %d;", pfx(lvl), pad_type, pad_bits);
+		off_diff -= pad_bits;
+	}
+}
+
+static void btf_dump_emit_struct_fwd(struct btf_dump *d, __u32 id,
+				     const struct btf_type *t)
+{
+	btf_dump_printf(d, "%s %s",
+			btf_kind_of(t) == BTF_KIND_STRUCT ? "struct" : "union",
+			btf_dump_type_name(d, id));
+}
+
+static void btf_dump_emit_struct_def(struct btf_dump *d,
+				     __u32 id,
+				     const struct btf_type *t,
+				     int lvl)
+{
+	const struct btf_member *m = (void *)(t + 1);
+	bool kflag = btf_kflag_of(t), is_struct;
+	int align, i, packed, off = 0;
+	__u16 vlen = btf_vlen_of(t);
+
+	is_struct = btf_kind_of(t) == BTF_KIND_STRUCT;
+	packed = is_struct ? btf_is_struct_packed(d->btf, id, t) : 0;
+	align = packed ? 1 : btf_align_of(d->btf, id);
+
+	btf_dump_printf(d, "%s%s%s {",
+			is_struct ? "struct" : "union",
+			t->name_off ? " " : "",
+			btf_dump_type_name(d, id));
+
+	for (i = 0; i < vlen; i++, m++) {
+		const char *fname;
+		int m_off, m_sz;
+
+		fname = btf_name_of(d, m->name_off);
+		m_sz = kflag ? BTF_MEMBER_BITFIELD_SIZE(m->offset) : 0;
+		m_off = kflag ? BTF_MEMBER_BIT_OFFSET(m->offset) : m->offset;
+		align = packed ? 1 : btf_align_of(d->btf, m->type);
+
+		btf_dump_emit_bit_padding(d, off, m_off, m_sz, align, lvl + 1);
+		btf_dump_printf(d, "\n%s", pfx(lvl + 1));
+		btf_dump_emit_type_decl(d, m->type, fname, lvl + 1);
+
+		if (m_sz) {
+			btf_dump_printf(d, ": %d", m_sz);
+			off = m_off + m_sz;
+		} else {
+			m_sz = max(0, btf__resolve_size(d->btf, m->type));
+			off = m_off + m_sz * 8;
+		}
+		btf_dump_printf(d, ";");
+	}
+
+	if (vlen)
+		btf_dump_printf(d, "\n");
+	btf_dump_printf(d, "%s}", pfx(lvl));
+	if (packed)
+		btf_dump_printf(d, " __attribute__((packed))");
+}
+
+static void btf_dump_emit_enum_fwd(struct btf_dump *d, __u32 id,
+				   const struct btf_type *t)
+{
+	btf_dump_printf(d, "enum %s", btf_dump_type_name(d, id));
+}
+
+static void btf_dump_emit_enum_def(struct btf_dump *d, __u32 id,
+				   const struct btf_type *t,
+				   int lvl)
+{
+	const struct btf_enum *v = (void *)(t+1);
+	__u16 vlen = btf_vlen_of(t);
+	const char *name;
+	size_t dup_cnt;
+	int i;
+
+	btf_dump_printf(d, "enum%s%s",
+			t->name_off ? " " : "",
+			btf_dump_type_name(d, id));
+
+	if (vlen) {
+		btf_dump_printf(d, " {");
+		for (i = 0; i < vlen; i++, v++) {
+			name = btf_name_of(d, v->name_off);
+			/* enumerators share namespace with typedef idents */
+			dup_cnt = btf_dump_name_dups(d, d->ident_names, name);
+			if (dup_cnt > 1) {
+				btf_dump_printf(d, "\n%s%s___%zu = %d,",
+						pfx(lvl + 1), name, dup_cnt,
+						(__s32)v->val);
+			} else {
+				btf_dump_printf(d, "\n%s%s = %d,",
+						pfx(lvl + 1), name,
+						(__s32)v->val);
+			}
+		}
+		btf_dump_printf(d, "\n%s}", pfx(lvl));
+	}
+}
+
+static void btf_dump_emit_fwd_def(struct btf_dump *d, __u32 id,
+				  const struct btf_type *t)
+{
+	const char *name = btf_dump_type_name(d, id);
+
+	if (btf_kflag_of(t))
+		btf_dump_printf(d, "union %s", name);
+	else
+		btf_dump_printf(d, "struct %s", name);
+}
+
+static void btf_dump_emit_typedef_def(struct btf_dump *d, __u32 id,
+				     const struct btf_type *t, int lvl)
+{
+	const char *name = btf_dump_ident_name(d, id);
+
+	btf_dump_printf(d, "typedef ");
+	btf_dump_emit_type_decl(d, t->type, name, lvl);
+}
+
+static int btf_dump_push_decl_stack_id(struct btf_dump *d, __u32 id)
+{
+	__u32 *new_stack;
+	size_t new_cap;
+
+	if (d->decl_stack_cnt >= d->decl_stack_cap) {
+		new_cap = max(16, d->decl_stack_cap * 3 / 2);
+		new_stack = realloc(d->decl_stack,
+				    new_cap * sizeof(new_stack[0]));
+		if (!new_stack)
+			return -ENOMEM;
+		d->decl_stack = new_stack;
+		d->decl_stack_cap = new_cap;
+	}
+
+	d->decl_stack[d->decl_stack_cnt++] = id;
+
+	return 0;
+}
+
+/*
+ * Emit type declaration (e.g., field type declaration in a struct or argument
+ * declaration in function prototype) in correct C syntax.
+ *
+ * For most types it's trivial, but there are few quirky type declaration
+ * cases worth mentioning:
+ *   - function prototypes (especially nesting of function prototypes);
+ *   - arrays;
+ *   - const/volatile/restrict for pointers vs other types.
+ *
+ * For a good discussion of *PARSING* C syntax (as a human), see
+ * Peter van der Linden's "Expert C Programming: Deep C Secrets",
+ * Ch.3 "Unscrambling Declarations in C".
+ *
+ * It won't help with BTF to C conversion much, though, as it's an opposite
+ * problem. So we came up with this algorithm in reverse to van der Linden's
+ * parsing algorithm. It goes from structured BTF representation of type
+ * declaration to a valid compilable C syntax.
+ *
+ * For instance, consider this C typedef:
+ *	typedef const int * const * arr[10] arr_t;
+ * It will be represented in BTF with this chain of BTF types:
+ *	[typedef] -> [array] -> [ptr] -> [const] -> [ptr] -> [const] -> [int]
+ *
+ * Notice how [const] modifier always goes before type it modifies in BTF type
+ * graph, but in C syntax, const/volatile/restrict modifiers are written to
+ * the right of pointers, but to the left of other types. There are also other
+ * quirks, like function pointers, arrays of them, functions returning other
+ * functions, etc.
+ *
+ * We handle that by pushing all the types to a stack, until we hit "terminal"
+ * type (int/enum/struct/union/fwd). Then depending on the kind of a type on
+ * top of a stack, modifiers are handled differently. Array/function pointers
+ * have also wildly different syntax and how nesting of them are done. See
+ * code for authoritative definition.
+ *
+ * To avoid allocating new stack for each independent chain of BTF types, we
+ * share one bigger stack, with each chain working only on its own local view
+ * of a stack frame. Some care is required to "pop" stack frames after
+ * processing type declaration chain.
+ */
+static void btf_dump_emit_type_decl(struct btf_dump *d, __u32 id,
+				    const char *fname, int lvl)
+{
+	struct id_stack decl_stack;
+	const struct btf_type *t;
+	int err, stack_start;
+	__u16 kind;
+
+	stack_start = d->decl_stack_cnt;
+	for (;;) {
+		err = btf_dump_push_decl_stack_id(d, id);
+		if (err < 0) {
+			/*
+			 * if we don't have enough memory for entire type decl
+			 * chain, restore stack, emit warning, and try to
+			 * proceed nevertheless
+			 */
+			pr_warning("not enough memory for decl stack:%d", err);
+			d->decl_stack_cnt = stack_start;
+			return;
+		}
+
+		/* VOID */
+		if (id == 0)
+			break;
+
+		t = btf__type_by_id(d->btf, id);
+		kind = btf_kind_of(t);
+		switch (kind) {
+		case BTF_KIND_PTR:
+		case BTF_KIND_VOLATILE:
+		case BTF_KIND_CONST:
+		case BTF_KIND_RESTRICT:
+		case BTF_KIND_FUNC_PROTO:
+			id = t->type;
+			break;
+		case BTF_KIND_ARRAY: {
+			const struct btf_array *a = (void *)(t + 1);
+
+			id = a->type;
+			break;
+		}
+		case BTF_KIND_INT:
+		case BTF_KIND_ENUM:
+		case BTF_KIND_FWD:
+		case BTF_KIND_STRUCT:
+		case BTF_KIND_UNION:
+		case BTF_KIND_TYPEDEF:
+			goto done;
+		default:
+			pr_warning("unexpected type in decl chain, kind:%u, id:[%u]\n",
+				   kind, id);
+			goto done;
+		}
+	}
+done:
+	/*
+	 * We might be inside a chain of declarations (e.g., array of function
+	 * pointers returning anonymous (so inlined) structs, having another
+	 * array field). Each of those needs its own "stack frame" to handle
+	 * emitting of declarations. Those stack frames are non-overlapping
+	 * portions of shared btf_dump->decl_stack. To make it a bit nicer to
+	 * handle this set of nested stacks, we create a view corresponding to
+	 * our own "stack frame" and work with it as an independent stack.
+	 * We'll need to clean up after emit_type_chain() returns, though.
+	 */
+	decl_stack.ids = d->decl_stack + stack_start;
+	decl_stack.cnt = d->decl_stack_cnt - stack_start;
+	btf_dump_emit_type_chain(d, &decl_stack, fname, lvl);
+	/*
+	 * emit_type_chain() guarantees that it will pop its entire decl_stack
+	 * frame before returning. But it works with a read-only view into
+	 * decl_stack, so it doesn't actually pop anything from the
+	 * perspective of shared btf_dump->decl_stack, per se. We need to
+	 * reset decl_stack state to how it was before us to avoid it growing
+	 * all the time.
+	 */
+	d->decl_stack_cnt = stack_start;
+}
+
+static void btf_dump_emit_mods(struct btf_dump *d, struct id_stack *decl_stack)
+{
+	const struct btf_type *t;
+	__u32 id;
+
+	while (decl_stack->cnt) {
+		id = decl_stack->ids[decl_stack->cnt - 1];
+		t = btf__type_by_id(d->btf, id);
+
+		switch (btf_kind_of(t)) {
+		case BTF_KIND_VOLATILE:
+			btf_dump_printf(d, "volatile ");
+			break;
+		case BTF_KIND_CONST:
+			btf_dump_printf(d, "const ");
+			break;
+		case BTF_KIND_RESTRICT:
+			btf_dump_printf(d, "restrict ");
+			break;
+		default:
+			return;
+		}
+		decl_stack->cnt--;
+	}
+}
+
+static bool btf_is_mod_kind(const struct btf *btf, __u32 id)
+{
+	const struct btf_type *t = btf__type_by_id(btf, id);
+
+	switch (btf_kind_of(t)) {
+	case BTF_KIND_VOLATILE:
+	case BTF_KIND_CONST:
+	case BTF_KIND_RESTRICT:
+		return true;
+	default:
+		return false;
+	}
+}
+
+static void btf_dump_emit_name(const struct btf_dump *d,
+			       const char *name, bool last_was_ptr)
+{
+	bool separate = name[0] && !last_was_ptr;
+
+	btf_dump_printf(d, "%s%s", separate ? " " : "", name);
+}
+
+static void btf_dump_emit_type_chain(struct btf_dump *d,
+				     struct id_stack *decls,
+				     const char *fname, int lvl)
+{
+	/*
+	 * last_was_ptr is used to determine if we need to separate pointer
+	 * asterisk (*) from previous part of type signature with space, so
+	 * that we get `int ***`, instead of `int * * *`. We default to true
+	 * for cases where we have single pointer in a chain. E.g., in ptr ->
+	 * func_proto case. func_proto will start a new emit_type_chain call
+	 * with just ptr, which should be emitted as (*) or (*<fname>), so we
+	 * don't want to prepend space for that last pointer.
+	 */
+	bool last_was_ptr = true;
+	const struct btf_type *t;
+	const char *name;
+	__u16 kind;
+	__u32 id;
+
+	while (decls->cnt) {
+		id = decls->ids[--decls->cnt];
+		if (id == 0) {
+			/* VOID is a special snowflake */
+			btf_dump_emit_mods(d, decls);
+			btf_dump_printf(d, "void");
+			last_was_ptr = false;
+			continue;
+		}
+
+		t = btf__type_by_id(d->btf, id);
+		kind = btf_kind_of(t);
+
+		switch (kind) {
+		case BTF_KIND_INT:
+			btf_dump_emit_mods(d, decls);
+			name = btf_name_of(d, t->name_off);
+			btf_dump_printf(d, "%s", name);
+			break;
+		case BTF_KIND_STRUCT:
+		case BTF_KIND_UNION:
+			btf_dump_emit_mods(d, decls);
+			/* inline anonymous struct/union */
+			if (t->name_off == 0)
+				btf_dump_emit_struct_def(d, id, t, lvl);
+			else
+				btf_dump_emit_struct_fwd(d, id, t);
+			break;
+		case BTF_KIND_ENUM:
+			btf_dump_emit_mods(d, decls);
+			/* inline anonymous enum */
+			if (t->name_off == 0)
+				btf_dump_emit_enum_def(d, id, t, lvl);
+			else
+				btf_dump_emit_enum_fwd(d, id, t);
+			break;
+		case BTF_KIND_FWD:
+			btf_dump_emit_mods(d, decls);
+			btf_dump_emit_fwd_def(d, id, t);
+			break;
+		case BTF_KIND_TYPEDEF:
+			btf_dump_emit_mods(d, decls);
+			btf_dump_printf(d, "%s", btf_dump_ident_name(d, id));
+			break;
+		case BTF_KIND_PTR:
+			btf_dump_printf(d, "%s", last_was_ptr ? "*" : " *");
+			break;
+		case BTF_KIND_VOLATILE:
+			btf_dump_printf(d, " volatile");
+			break;
+		case BTF_KIND_CONST:
+			btf_dump_printf(d, " const");
+			break;
+		case BTF_KIND_RESTRICT:
+			btf_dump_printf(d, " restrict");
+			break;
+		case BTF_KIND_ARRAY: {
+			const struct btf_array *a = (void *)(t + 1);
+			const struct btf_type *next_t;
+			__u32 next_id;
+			bool multidim;
+			/*
+			 * GCC has a bug
+			 * (https://gcc.gnu.org/bugzilla/show_bug.cgi?id=8354)
+			 * which causes it to emit extra const/volatile
+			 * modifiers for an array, if array's element type has
+			 * const/volatile modifiers. Clang doesn't do that.
+			 * In general, it doesn't seem very meaningful to have
+			 * a const/volatile modifier for array, so we are
+			 * going to silently skip them here.
+			 */
+			while (decls->cnt) {
+				next_id = decls->ids[decls->cnt - 1];
+				if (btf_is_mod_kind(d->btf, next_id))
+					decls->cnt--;
+				else
+					break;
+			}
+
+			if (decls->cnt == 0) {
+				btf_dump_emit_name(d, fname, last_was_ptr);
+				btf_dump_printf(d, "[%u]", a->nelems);
+				return;
+			}
+
+			next_t = btf__type_by_id(d->btf, next_id);
+			multidim = btf_kind_of(next_t) == BTF_KIND_ARRAY;
+			/* we need space if we have named non-pointer */
+			if (fname[0] && !last_was_ptr)
+				btf_dump_printf(d, " ");
+			/* no parentheses for multi-dimensional array */
+			if (!multidim)
+				btf_dump_printf(d, "(");
+			btf_dump_emit_type_chain(d, decls, fname, lvl);
+			if (!multidim)
+				btf_dump_printf(d, ")");
+			btf_dump_printf(d, "[%u]", a->nelems);
+			return;
+		}
+		case BTF_KIND_FUNC_PROTO: {
+			const struct btf_param *p = (void *)(t + 1);
+			__u16 vlen = btf_vlen_of(t);
+			int i;
+
+			btf_dump_emit_mods(d, decls);
+			if (decls->cnt) {
+				btf_dump_printf(d, " (");
+				btf_dump_emit_type_chain(d, decls, fname, lvl);
+				btf_dump_printf(d, ")");
+			} else {
+				btf_dump_emit_name(d, fname, last_was_ptr);
+			}
+			btf_dump_printf(d, "(");
+			/*
+			 * Clang for BPF target generates func_proto with no
+			 * args as a func_proto with a single void arg (e.g.,
+			 * `int (*f)(void)` vs just `int (*f)()`). We are
+			 * going to pretend there are no args for such case.
+			 */
+			if (vlen == 1 && p->type == 0) {
+				btf_dump_printf(d, ")");
+				return;
+			}
+
+			for (i = 0; i < vlen; i++, p++) {
+				if (i > 0)
+					btf_dump_printf(d, ", ");
+
+				/* last arg of type void is vararg */
+				if (i == vlen - 1 && p->type == 0) {
+					btf_dump_printf(d, "...");
+					break;
+				}
+
+				name = btf_name_of(d, p->name_off);
+				btf_dump_emit_type_decl(d, p->type, name, lvl);
+			}
+
+			btf_dump_printf(d, ")");
+			return;
+		}
+		default:
+			pr_warning("unexpected type in decl chain, kind:%u, id:[%u]\n",
+				   kind, id);
+			return;
+		}
+
+		last_was_ptr = kind == BTF_KIND_PTR;
+	}
+
+	btf_dump_emit_name(d, fname, last_was_ptr);
+}
+
+/* return number of duplicates (occurrences) of a given name */
+static size_t btf_dump_name_dups(struct btf_dump *d, struct hashmap *name_map,
+				 const char *orig_name)
+{
+	size_t dup_cnt = 0;
+
+	hashmap__find(name_map, orig_name, (void **)&dup_cnt);
+	dup_cnt++;
+	hashmap__set(name_map, orig_name, (void *)dup_cnt, NULL, NULL);
+
+	return dup_cnt;
+}
+
+static const char *btf_dump_resolve_name(struct btf_dump *d, __u32 id,
+					 struct hashmap *name_map)
+{
+	struct btf_dump_type_aux_state *s = &d->type_states[id];
+	const struct btf_type *t = btf__type_by_id(d->btf, id);
+	const char *orig_name = btf_name_of(d, t->name_off);
+	const char **cached_name = &d->cached_names[id];
+	size_t dup_cnt;
+
+	if (t->name_off == 0)
+		return "";
+
+	if (s->name_resolved)
+		return *cached_name ? *cached_name : orig_name;
+
+	dup_cnt = btf_dump_name_dups(d, name_map, orig_name);
+	if (dup_cnt > 1) {
+		const size_t max_len = 256;
+		char new_name[max_len];
+
+		snprintf(new_name, max_len, "%s___%zu", orig_name, dup_cnt);
+		*cached_name = strdup(new_name);
+	}
+
+	s->name_resolved = 1;
+	return *cached_name ? *cached_name : orig_name;
+}
+
+static const char *btf_dump_type_name(struct btf_dump *d, __u32 id)
+{
+	return btf_dump_resolve_name(d, id, d->type_names);
+}
+
+static const char *btf_dump_ident_name(struct btf_dump *d, __u32 id)
+{
+	return btf_dump_resolve_name(d, id, d->ident_names);
+}
diff --git a/tools/lib/bpf/hashmap.c b/tools/lib/bpf/hashmap.c
new file mode 100644
index 000000000000..6122272943e6
--- /dev/null
+++ b/tools/lib/bpf/hashmap.c
@@ -0,0 +1,229 @@
+// SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
+
+/*
+ * Generic non-thread safe hash map implementation.
+ *
+ * Copyright (c) 2019 Facebook
+ */
+#include <stdint.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <errno.h>
+#include <linux/err.h>
+#include "hashmap.h"
+
+/* start with 4 buckets */
+#define HASHMAP_MIN_CAP_BITS 2
+
+static void hashmap_add_entry(struct hashmap_entry **pprev,
+			      struct hashmap_entry *entry)
+{
+	entry->next = *pprev;
+	*pprev = entry;
+}
+
+static void hashmap_del_entry(struct hashmap_entry **pprev,
+			      struct hashmap_entry *entry)
+{
+	*pprev = entry->next;
+	entry->next = NULL;
+}
+
+void hashmap__init(struct hashmap *map, hashmap_hash_fn hash_fn,
+		   hashmap_equal_fn equal_fn, void *ctx)
+{
+	map->hash_fn = hash_fn;
+	map->equal_fn = equal_fn;
+	map->ctx = ctx;
+
+	map->buckets = NULL;
+	map->cap = 0;
+	map->cap_bits = 0;
+	map->sz = 0;
+}
+
+struct hashmap *hashmap__new(hashmap_hash_fn hash_fn,
+			     hashmap_equal_fn equal_fn,
+			     void *ctx)
+{
+	struct hashmap *map = malloc(sizeof(struct hashmap));
+
+	if (!map)
+		return ERR_PTR(-ENOMEM);
+	hashmap__init(map, hash_fn, equal_fn, ctx);
+	return map;
+}
+
+void hashmap__clear(struct hashmap *map)
+{
+	free(map->buckets);
+	map->cap = map->cap_bits = map->sz = 0;
+}
+
+void hashmap__free(struct hashmap *map)
+{
+	if (!map)
+		return;
+
+	hashmap__clear(map);
+	free(map);
+}
+
+size_t hashmap__size(const struct hashmap *map)
+{
+	return map->sz;
+}
+
+size_t hashmap__capacity(const struct hashmap *map)
+{
+	return map->cap;
+}
+
+static bool hashmap_needs_to_grow(struct hashmap *map)
+{
+	/* grow if empty or more than 75% filled */
+	return (map->cap == 0) || ((map->sz + 1) * 4 / 3 > map->cap);
+}
+
+static int hashmap_grow(struct hashmap *map)
+{
+	struct hashmap_entry **new_buckets;
+	struct hashmap_entry *cur, *tmp;
+	size_t new_cap_bits, new_cap;
+	size_t h;
+	int bkt;
+
+	new_cap_bits = map->cap_bits + 1;
+	if (new_cap_bits < HASHMAP_MIN_CAP_BITS)
+		new_cap_bits = HASHMAP_MIN_CAP_BITS;
+
+	new_cap = 1UL << new_cap_bits;
+	new_buckets = calloc(new_cap, sizeof(new_buckets[0]));
+	if (!new_buckets)
+		return -ENOMEM;
+
+	hashmap__for_each_entry_safe(map, cur, tmp, bkt) {
+		h = hash_bits(map->hash_fn(cur->key, map->ctx), new_cap_bits);
+		hashmap_add_entry(&new_buckets[h], cur);
+	}
+
+	map->cap = new_cap;
+	map->cap_bits = new_cap_bits;
+	free(map->buckets);
+	map->buckets = new_buckets;
+
+	return 0;
+}
+
+static bool hashmap_find_entry(const struct hashmap *map,
+			       const void *key, size_t hash,
+			       struct hashmap_entry ***pprev,
+			       struct hashmap_entry **entry)
+{
+	struct hashmap_entry *cur, **prev_ptr;
+
+	if (!map->buckets)
+		return false;
+
+	for (prev_ptr = &map->buckets[hash], cur = *prev_ptr;
+	     cur;
+	     prev_ptr = &cur->next, cur = cur->next) {
+		if (map->equal_fn(cur->key, key, map->ctx)) {
+			if (pprev)
+				*pprev = prev_ptr;
+			*entry = cur;
+			return true;
+		}
+	}
+
+	return false;
+}
+
+int hashmap__insert(struct hashmap *map, const void *key, void *value,
+		    enum hashmap_insert_strategy strategy,
+		    const void **old_key, void **old_value)
+{
+	struct hashmap_entry *entry;
+	size_t h;
+	int err;
+
+	if (old_key)
+		*old_key = NULL;
+	if (old_value)
+		*old_value = NULL;
+
+	h = hash_bits(map->hash_fn(key, map->ctx), map->cap_bits);
+	if (strategy != HASHMAP_APPEND &&
+	    hashmap_find_entry(map, key, h, NULL, &entry)) {
+		if (old_key)
+			*old_key = entry->key;
+		if (old_value)
+			*old_value = entry->value;
+
+		if (strategy == HASHMAP_SET || strategy == HASHMAP_UPDATE) {
+			entry->key = key;
+			entry->value = value;
+			return 0;
+		} else if (strategy == HASHMAP_ADD) {
+			return -EEXIST;
+		}
+	}
+
+	if (strategy == HASHMAP_UPDATE)
+		return -ENOENT;
+
+	if (hashmap_needs_to_grow(map)) {
+		err = hashmap_grow(map);
+		if (err)
+			return err;
+		h = hash_bits(map->hash_fn(key, map->ctx), map->cap_bits);
+	}
+
+	entry = malloc(sizeof(struct hashmap_entry));
+	if (!entry)
+		return -ENOMEM;
+
+	entry->key = key;
+	entry->value = value;
+	hashmap_add_entry(&map->buckets[h], entry);
+	map->sz++;
+
+	return 0;
+}
+
+bool hashmap__find(const struct hashmap *map, const void *key, void **value)
+{
+	struct hashmap_entry *entry;
+	size_t h;
+
+	h = hash_bits(map->hash_fn(key, map->ctx), map->cap_bits);
+	if (!hashmap_find_entry(map, key, h, NULL, &entry))
+		return false;
+
+	if (value)
+		*value = entry->value;
+	return true;
+}
+
+bool hashmap__delete(struct hashmap *map, const void *key,
+		     const void **old_key, void **old_value)
+{
+	struct hashmap_entry **pprev, *entry;
+	size_t h;
+
+	h = hash_bits(map->hash_fn(key, map->ctx), map->cap_bits);
+	if (!hashmap_find_entry(map, key, h, &pprev, &entry))
+		return false;
+
+	if (old_key)
+		*old_key = entry->key;
+	if (old_value)
+		*old_value = entry->value;
+
+	hashmap_del_entry(pprev, entry);
+	free(entry);
+	map->sz--;
+
+	return true;
+}
+
diff --git a/tools/lib/bpf/hashmap.h b/tools/lib/bpf/hashmap.h
new file mode 100644
index 000000000000..03748a742146
--- /dev/null
+++ b/tools/lib/bpf/hashmap.h
@@ -0,0 +1,173 @@
+/* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */
+
+/*
+ * Generic non-thread safe hash map implementation.
+ *
+ * Copyright (c) 2019 Facebook
+ */
+#ifndef __LIBBPF_HASHMAP_H
+#define __LIBBPF_HASHMAP_H
+
+#include <stdbool.h>
+#include <stddef.h>
+#include "libbpf_internal.h"
+
+static inline size_t hash_bits(size_t h, int bits)
+{
+	/* shuffle bits and return requested number of upper bits */
+	return (h * 11400714819323198485llu) >> (__WORDSIZE - bits);
+}
+
+typedef size_t (*hashmap_hash_fn)(const void *key, void *ctx);
+typedef bool (*hashmap_equal_fn)(const void *key1, const void *key2, void *ctx);
+
+struct hashmap_entry {
+	const void *key;
+	void *value;
+	struct hashmap_entry *next;
+};
+
+struct hashmap {
+	hashmap_hash_fn hash_fn;
+	hashmap_equal_fn equal_fn;
+	void *ctx;
+
+	struct hashmap_entry **buckets;
+	size_t cap;
+	size_t cap_bits;
+	size_t sz;
+};
+
+#define HASHMAP_INIT(hash_fn, equal_fn, ctx) {	\
+	.hash_fn = (hash_fn),			\
+	.equal_fn = (equal_fn),			\
+	.ctx = (ctx),				\
+	.buckets = NULL,			\
+	.cap = 0,				\
+	.cap_bits = 0,				\
+	.sz = 0,				\
+}
+
+void hashmap__init(struct hashmap *map, hashmap_hash_fn hash_fn,
+		   hashmap_equal_fn equal_fn, void *ctx);
+struct hashmap *hashmap__new(hashmap_hash_fn hash_fn,
+			     hashmap_equal_fn equal_fn,
+			     void *ctx);
+void hashmap__clear(struct hashmap *map);
+void hashmap__free(struct hashmap *map);
+
+size_t hashmap__size(const struct hashmap *map);
+size_t hashmap__capacity(const struct hashmap *map);
+
+/*
+ * Hashmap insertion strategy:
+ * - HASHMAP_ADD - only add key/value if key doesn't exist yet;
+ * - HASHMAP_SET - add key/value pair if key doesn't exist yet; otherwise,
+ *   update value;
+ * - HASHMAP_UPDATE - update value, if key already exists; otherwise, do
+ *   nothing and return -ENOENT;
+ * - HASHMAP_APPEND - always add key/value pair, even if key already exists.
+ *   This turns hashmap into a multimap by allowing multiple values to be
+ *   associated with the same key. Most useful read API for such hashmap is
+ *   hashmap__for_each_key_entry() iteration. If hashmap__find() is still
+ *   used, it will return last inserted key/value entry (first in a bucket
+ *   chain).
+ */
+enum hashmap_insert_strategy {
+	HASHMAP_ADD,
+	HASHMAP_SET,
+	HASHMAP_UPDATE,
+	HASHMAP_APPEND,
+};
+
+/*
+ * hashmap__insert() adds key/value entry w/ various semantics, depending on
+ * provided strategy value. If a given key/value pair replaced already
+ * existing key/value pair, both old key and old value will be returned
+ * through old_key and old_value to allow calling code do proper memory
+ * management.
+ */
+int hashmap__insert(struct hashmap *map, const void *key, void *value,
+		    enum hashmap_insert_strategy strategy,
+		    const void **old_key, void **old_value);
+
+static inline int hashmap__add(struct hashmap *map,
+			       const void *key, void *value)
+{
+	return hashmap__insert(map, key, value, HASHMAP_ADD, NULL, NULL);
+}
+
+static inline int hashmap__set(struct hashmap *map,
+			       const void *key, void *value,
+			       const void **old_key, void **old_value)
+{
+	return hashmap__insert(map, key, value, HASHMAP_SET,
+			       old_key, old_value);
+}
+
+static inline int hashmap__update(struct hashmap *map,
+				  const void *key, void *value,
+				  const void **old_key, void **old_value)
+{
+	return hashmap__insert(map, key, value, HASHMAP_UPDATE,
+			       old_key, old_value);
+}
+
+static inline int hashmap__append(struct hashmap *map,
+				  const void *key, void *value)
+{
+	return hashmap__insert(map, key, value, HASHMAP_APPEND, NULL, NULL);
+}
+
+bool hashmap__delete(struct hashmap *map, const void *key,
+		     const void **old_key, void **old_value);
+
+bool hashmap__find(const struct hashmap *map, const void *key, void **value);
+
+/*
+ * hashmap__for_each_entry - iterate over all entries in hashmap
+ * @map: hashmap to iterate
+ * @cur: struct hashmap_entry * used as a loop cursor
+ * @bkt: integer used as a bucket loop cursor
+ */
+#define hashmap__for_each_entry(map, cur, bkt)				    \
+	for (bkt = 0; bkt < map->cap; bkt++)				    \
+		for (cur = map->buckets[bkt]; cur; cur = cur->next)
+
+/*
+ * hashmap__for_each_entry_safe - iterate over all entries in hashmap, safe
+ * against removals
+ * @map: hashmap to iterate
+ * @cur: struct hashmap_entry * used as a loop cursor
+ * @tmp: struct hashmap_entry * used as a temporary next cursor storage
+ * @bkt: integer used as a bucket loop cursor
+ */
+#define hashmap__for_each_entry_safe(map, cur, tmp, bkt)		    \
+	for (bkt = 0; bkt < map->cap; bkt++)				    \
+		for (cur = map->buckets[bkt];				    \
+		     cur && ({tmp = cur->next; true; });		    \
+		     cur = tmp)
+
+/*
+ * hashmap__for_each_key_entry - iterate over entries associated with given key
+ * @map: hashmap to iterate
+ * @cur: struct hashmap_entry * used as a loop cursor
+ * @key: key to iterate entries for
+ */
+#define hashmap__for_each_key_entry(map, cur, _key)			    \
+	for (cur = ({ size_t bkt = hash_bits(map->hash_fn((_key), map->ctx),\
+					     map->cap_bits);		    \
+		     map->buckets ? map->buckets[bkt] : NULL; });	    \
+	     cur;							    \
+	     cur = cur->next)						    \
+		if (map->equal_fn(cur->key, (_key), map->ctx))
+
+#define hashmap__for_each_key_entry_safe(map, cur, tmp, _key)		    \
+	for (cur = ({ size_t bkt = hash_bits(map->hash_fn((_key), map->ctx),\
+					     map->cap_bits);		    \
+		     cur = map->buckets ? map->buckets[bkt] : NULL; });	    \
+	     cur && ({ tmp = cur->next; true; });			    \
+	     cur = tmp)							    \
+		if (map->equal_fn(cur->key, (_key), map->ctx))
+
+#endif /* __LIBBPF_HASHMAP_H */
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 197b574406b3..ba89d9727137 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -188,6 +188,7 @@ struct bpf_program {
 	void *line_info;
 	__u32 line_info_rec_size;
 	__u32 line_info_cnt;
+	__u32 prog_flags;
 };
 
 enum libbpf_map_type {
@@ -348,8 +349,11 @@ static int
 bpf_program__init(void *data, size_t size, char *section_name, int idx,
 		  struct bpf_program *prog)
 {
-	if (size < sizeof(struct bpf_insn)) {
-		pr_warning("corrupted section '%s'\n", section_name);
+	const size_t bpf_insn_sz = sizeof(struct bpf_insn);
+
+	if (size == 0 || size % bpf_insn_sz) {
+		pr_warning("corrupted section '%s', size: %zu\n",
+			   section_name, size);
 		return -EINVAL;
 	}
 
@@ -375,9 +379,8 @@ bpf_program__init(void *data, size_t size, char *section_name, int idx,
 			   section_name);
 		goto errout;
 	}
-	prog->insns_cnt = size / sizeof(struct bpf_insn);
-	memcpy(prog->insns, data,
-	       prog->insns_cnt * sizeof(struct bpf_insn));
+	prog->insns_cnt = size / bpf_insn_sz;
+	memcpy(prog->insns, data, size);
 	prog->idx = idx;
 	prog->instances.fds = NULL;
 	prog->instances.nr = -1;
@@ -494,15 +497,14 @@ static struct bpf_object *bpf_object__new(const char *path,
 
 	strcpy(obj->path, path);
 	/* Using basename() GNU version which doesn't modify arg. */
-	strncpy(obj->name, basename((void *)path),
-		sizeof(obj->name) - 1);
+	strncpy(obj->name, basename((void *)path), sizeof(obj->name) - 1);
 	end = strchr(obj->name, '.');
 	if (end)
 		*end = 0;
 
 	obj->efile.fd = -1;
 	/*
-	 * Caller of this function should also calls
+	 * Caller of this function should also call
 	 * bpf_object__elf_finish() after data collection to return
 	 * obj_buf to user. If not, we should duplicate the buffer to
 	 * avoid user freeing them before elf finish.
@@ -562,38 +564,35 @@ static int bpf_object__elf_init(struct bpf_object *obj)
 	} else {
 		obj->efile.fd = open(obj->path, O_RDONLY);
 		if (obj->efile.fd < 0) {
-			char errmsg[STRERR_BUFSIZE];
-			char *cp = libbpf_strerror_r(errno, errmsg,
-						     sizeof(errmsg));
+			char errmsg[STRERR_BUFSIZE], *cp;
 
+			err = -errno;
+			cp = libbpf_strerror_r(err, errmsg, sizeof(errmsg));
 			pr_warning("failed to open %s: %s\n", obj->path, cp);
-			return -errno;
+			return err;
 		}
 
 		obj->efile.elf = elf_begin(obj->efile.fd,
-				LIBBPF_ELF_C_READ_MMAP,
-				NULL);
+					   LIBBPF_ELF_C_READ_MMAP, NULL);
 	}
 
 	if (!obj->efile.elf) {
-		pr_warning("failed to open %s as ELF file\n",
-				obj->path);
+		pr_warning("failed to open %s as ELF file\n", obj->path);
 		err = -LIBBPF_ERRNO__LIBELF;
 		goto errout;
 	}
 
 	if (!gelf_getehdr(obj->efile.elf, &obj->efile.ehdr)) {
-		pr_warning("failed to get EHDR from %s\n",
-				obj->path);
+		pr_warning("failed to get EHDR from %s\n", obj->path);
 		err = -LIBBPF_ERRNO__FORMAT;
 		goto errout;
 	}
 	ep = &obj->efile.ehdr;
 
 	/* Old LLVM set e_machine to EM_NONE */
-	if ((ep->e_type != ET_REL) || (ep->e_machine && (ep->e_machine != EM_BPF))) {
-		pr_warning("%s is not an eBPF object file\n",
-			obj->path);
+	if (ep->e_type != ET_REL ||
+	    (ep->e_machine && ep->e_machine != EM_BPF)) {
+		pr_warning("%s is not an eBPF object file\n", obj->path);
 		err = -LIBBPF_ERRNO__FORMAT;
 		goto errout;
 	}
@@ -604,47 +603,31 @@ errout:
 	return err;
 }
 
-static int
-bpf_object__check_endianness(struct bpf_object *obj)
-{
-	static unsigned int const endian = 1;
-
-	switch (obj->efile.ehdr.e_ident[EI_DATA]) {
-	case ELFDATA2LSB:
-		/* We are big endian, BPF obj is little endian. */
-		if (*(unsigned char const *)&endian != 1)
-			goto mismatch;
-		break;
-
-	case ELFDATA2MSB:
-		/* We are little endian, BPF obj is big endian. */
-		if (*(unsigned char const *)&endian != 0)
-			goto mismatch;
-		break;
-	default:
-		return -LIBBPF_ERRNO__ENDIAN;
-	}
-
-	return 0;
-
-mismatch:
-	pr_warning("Error: endianness mismatch.\n");
+static int bpf_object__check_endianness(struct bpf_object *obj)
+{
+#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
+	if (obj->efile.ehdr.e_ident[EI_DATA] == ELFDATA2LSB)
+		return 0;
+#elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
+	if (obj->efile.ehdr.e_ident[EI_DATA] == ELFDATA2MSB)
+		return 0;
+#else
+# error "Unrecognized __BYTE_ORDER__"
+#endif
+	pr_warning("endianness mismatch.\n");
 	return -LIBBPF_ERRNO__ENDIAN;
 }
 
 static int
-bpf_object__init_license(struct bpf_object *obj,
-			 void *data, size_t size)
+bpf_object__init_license(struct bpf_object *obj, void *data, size_t size)
 {
-	memcpy(obj->license, data,
-	       min(size, sizeof(obj->license) - 1));
+	memcpy(obj->license, data, min(size, sizeof(obj->license) - 1));
 	pr_debug("license of %s is %s\n", obj->path, obj->license);
 	return 0;
 }
 
 static int
-bpf_object__init_kversion(struct bpf_object *obj,
-			  void *data, size_t size)
+bpf_object__init_kversion(struct bpf_object *obj, void *data, size_t size)
 {
 	__u32 kver;
 
@@ -654,8 +637,7 @@ bpf_object__init_kversion(struct bpf_object *obj,
 	}
 	memcpy(&kver, data, sizeof(kver));
 	obj->kern_version = kver;
-	pr_debug("kernel version of %s is %x\n", obj->path,
-		 obj->kern_version);
+	pr_debug("kernel version of %s is %x\n", obj->path, obj->kern_version);
 	return 0;
 }
 
@@ -811,8 +793,7 @@ bpf_object__init_internal_map(struct bpf_object *obj, struct bpf_map *map,
 	def->key_size = sizeof(int);
 	def->value_size = data->d_size;
 	def->max_entries = 1;
-	def->map_flags = type == LIBBPF_MAP_RODATA ?
-			 BPF_F_RDONLY_PROG : 0;
+	def->map_flags = type == LIBBPF_MAP_RODATA ? BPF_F_RDONLY_PROG : 0;
 	if (data_buff) {
 		*data_buff = malloc(data->d_size);
 		if (!*data_buff) {
@@ -827,8 +808,7 @@ bpf_object__init_internal_map(struct bpf_object *obj, struct bpf_map *map,
 	return 0;
 }
 
-static int
-bpf_object__init_maps(struct bpf_object *obj, int flags)
+static int bpf_object__init_maps(struct bpf_object *obj, int flags)
 {
 	int i, map_idx, map_def_sz = 0, nr_syms, nr_maps = 0, nr_maps_glob = 0;
 	bool strict = !(flags & MAPS_RELAX_COMPAT);
@@ -930,6 +910,11 @@ bpf_object__init_maps(struct bpf_object *obj, int flags)
 		map_name = elf_strptr(obj->efile.elf,
 				      obj->efile.strtabidx,
 				      sym.st_name);
+		if (!map_name) {
+			pr_warning("failed to get map #%d name sym string for obj %s\n",
+				   map_idx, obj->path);
+			return -LIBBPF_ERRNO__FORMAT;
+		}
 
 		obj->maps[map_idx].libbpf_type = LIBBPF_MAP_UNSPEC;
 		obj->maps[map_idx].offset = sym.st_value;
@@ -1104,8 +1089,7 @@ static int bpf_object__elf_collect(struct bpf_object *obj, int flags)
 
 	/* Elf is corrupted/truncated, avoid calling elf_strptr. */
 	if (!elf_rawdata(elf_getscn(elf, ep->e_shstrndx), NULL)) {
-		pr_warning("failed to get e_shstrndx from %s\n",
-			   obj->path);
+		pr_warning("failed to get e_shstrndx from %s\n", obj->path);
 		return -LIBBPF_ERRNO__FORMAT;
 	}
 
@@ -1226,7 +1210,7 @@ static int bpf_object__elf_collect(struct bpf_object *obj, int flags)
 
 	if (!obj->efile.strtabidx || obj->efile.strtabidx >= idx) {
 		pr_warning("Corrupted ELF file: index of strtab invalid\n");
-		return LIBBPF_ERRNO__FORMAT;
+		return -LIBBPF_ERRNO__FORMAT;
 	}
 	if (btf_data) {
 		obj->btf = btf__new(btf_data->d_buf, btf_data->d_size);
@@ -1346,8 +1330,7 @@ bpf_program__collect_reloc(struct bpf_program *prog, GElf_Shdr *shdr,
 	size_t nr_maps = obj->nr_maps;
 	int i, nrels;
 
-	pr_debug("collecting relocating info for: '%s'\n",
-		 prog->section_name);
+	pr_debug("collecting relocating info for: '%s'\n", prog->section_name);
 	nrels = shdr->sh_size / shdr->sh_entsize;
 
 	prog->reloc_desc = malloc(sizeof(*prog->reloc_desc) * nrels);
@@ -1372,9 +1355,7 @@ bpf_program__collect_reloc(struct bpf_program *prog, GElf_Shdr *shdr,
 			return -LIBBPF_ERRNO__FORMAT;
 		}
 
-		if (!gelf_getsym(symbols,
-				 GELF_R_SYM(rel.r_info),
-				 &sym)) {
+		if (!gelf_getsym(symbols, GELF_R_SYM(rel.r_info), &sym)) {
 			pr_warning("relocation: symbol %"PRIx64" not found\n",
 				   GELF_R_SYM(rel.r_info));
 			return -LIBBPF_ERRNO__FORMAT;
@@ -1435,8 +1416,7 @@ bpf_program__collect_reloc(struct bpf_program *prog, GElf_Shdr *shdr,
 				if (maps[map_idx].libbpf_type != type)
 					continue;
 				if (type != LIBBPF_MAP_UNSPEC ||
-				    (type == LIBBPF_MAP_UNSPEC &&
-				     maps[map_idx].offset == sym.st_value)) {
+				    maps[map_idx].offset == sym.st_value) {
 					pr_debug("relocation: find map %zd (%s) for insn %u\n",
 						 map_idx, maps[map_idx].name, insn_idx);
 					break;
@@ -1444,7 +1424,7 @@ bpf_program__collect_reloc(struct bpf_program *prog, GElf_Shdr *shdr,
 			}
 
 			if (map_idx >= nr_maps) {
-				pr_warning("bpf relocation: map_idx %d large than %d\n",
+				pr_warning("bpf relocation: map_idx %d larger than %d\n",
 					   (int)map_idx, (int)nr_maps - 1);
 				return -LIBBPF_ERRNO__RELOC;
 			}
@@ -1756,7 +1736,7 @@ bpf_object__create_maps(struct bpf_object *obj)
 		create_attr.key_size = def->key_size;
 		create_attr.value_size = def->value_size;
 		create_attr.max_entries = def->max_entries;
-		create_attr.btf_fd = 0;
+		create_attr.btf_fd = -1;
 		create_attr.btf_key_type_id = 0;
 		create_attr.btf_value_type_id = 0;
 		if (bpf_map_type__is_map_in_map(def->type) &&
@@ -1770,11 +1750,11 @@ bpf_object__create_maps(struct bpf_object *obj)
 		}
 
 		*pfd = bpf_create_map_xattr(&create_attr);
-		if (*pfd < 0 && create_attr.btf_key_type_id) {
+		if (*pfd < 0 && create_attr.btf_fd >= 0) {
 			cp = libbpf_strerror_r(errno, errmsg, sizeof(errmsg));
 			pr_warning("Error in bpf_create_map_xattr(%s):%s(%d). Retrying without BTF.\n",
 				   map->name, cp, errno);
-			create_attr.btf_fd = 0;
+			create_attr.btf_fd = -1;
 			create_attr.btf_key_type_id = 0;
 			create_attr.btf_value_type_id = 0;
 			map->btf_key_type_id = 0;
@@ -1803,7 +1783,7 @@ err_out:
 			}
 		}
 
-		pr_debug("create map %s: fd=%d\n", map->name, *pfd);
+		pr_debug("created map %s: fd=%d\n", map->name, *pfd);
 	}
 
 	return 0;
@@ -1824,18 +1804,14 @@ check_btf_ext_reloc_err(struct bpf_program *prog, int err,
 	if (btf_prog_info) {
 		/*
 		 * Some info has already been found but has problem
-		 * in the last btf_ext reloc.  Must have to error
-		 * out.
+		 * in the last btf_ext reloc. Must have to error out.
 		 */
 		pr_warning("Error in relocating %s for sec %s.\n",
 			   info_name, prog->section_name);
 		return err;
 	}
 
-	/*
-	 * Have problem loading the very first info.  Ignore
-	 * the rest.
-	 */
+	/* Have problem loading the very first info. Ignore the rest. */
 	pr_warning("Cannot find %s for main program sec %s. Ignore all %s.\n",
 		   info_name, prog->section_name, info_name);
 	return 0;
@@ -2039,9 +2015,7 @@ static int bpf_object__collect_reloc(struct bpf_object *obj)
 			return -LIBBPF_ERRNO__RELOC;
 		}
 
-		err = bpf_program__collect_reloc(prog,
-						 shdr, data,
-						 obj);
+		err = bpf_program__collect_reloc(prog, shdr, data, obj);
 		if (err)
 			return err;
 	}
@@ -2058,6 +2032,9 @@ load_program(struct bpf_program *prog, struct bpf_insn *insns, int insns_cnt,
 	char *log_buf;
 	int ret;
 
+	if (!insns || !insns_cnt)
+		return -EINVAL;
+
 	memset(&load_attr, 0, sizeof(struct bpf_load_program_attr));
 	load_attr.prog_type = prog->type;
 	load_attr.expected_attach_type = prog->expected_attach_type;
@@ -2068,7 +2045,7 @@ load_program(struct bpf_program *prog, struct bpf_insn *insns, int insns_cnt,
 	load_attr.license = license;
 	load_attr.kern_version = kern_version;
 	load_attr.prog_ifindex = prog->prog_ifindex;
-	load_attr.prog_btf_fd = prog->btf_fd >= 0 ? prog->btf_fd : 0;
+	load_attr.prog_btf_fd = prog->btf_fd;
 	load_attr.func_info = prog->func_info;
 	load_attr.func_info_rec_size = prog->func_info_rec_size;
 	load_attr.func_info_cnt = prog->func_info_cnt;
@@ -2076,8 +2053,7 @@ load_program(struct bpf_program *prog, struct bpf_insn *insns, int insns_cnt,
 	load_attr.line_info_rec_size = prog->line_info_rec_size;
 	load_attr.line_info_cnt = prog->line_info_cnt;
 	load_attr.log_level = prog->log_level;
-	if (!load_attr.insns || !load_attr.insns_cnt)
-		return -EINVAL;
+	load_attr.prog_flags = prog->prog_flags;
 
 retry_load:
 	log_buf = malloc(log_buf_size);
@@ -2222,7 +2198,7 @@ static bool bpf_program__is_function_storage(struct bpf_program *prog,
 }
 
 static int
-bpf_object__load_progs(struct bpf_object *obj)
+bpf_object__load_progs(struct bpf_object *obj, int log_level)
 {
 	size_t i;
 	int err;
@@ -2230,6 +2206,7 @@ bpf_object__load_progs(struct bpf_object *obj)
 	for (i = 0; i < obj->nr_programs; i++) {
 		if (bpf_program__is_function_storage(&obj->programs[i], obj))
 			continue;
+		obj->programs[i].log_level |= log_level;
 		err = bpf_program__load(&obj->programs[i],
 					obj->license,
 					obj->kern_version);
@@ -2356,11 +2333,9 @@ struct bpf_object *bpf_object__open_buffer(void *obj_buf,
 		snprintf(tmp_name, sizeof(tmp_name), "%lx-%lx",
 			 (unsigned long)obj_buf,
 			 (unsigned long)obj_buf_sz);
-		tmp_name[sizeof(tmp_name) - 1] = '\0';
 		name = tmp_name;
 	}
-	pr_debug("loading object '%s' from buffer\n",
-		 name);
+	pr_debug("loading object '%s' from buffer\n", name);
 
 	return __bpf_object__open(name, obj_buf, obj_buf_sz, true, true);
 }
@@ -2381,10 +2356,14 @@ int bpf_object__unload(struct bpf_object *obj)
 	return 0;
 }
 
-int bpf_object__load(struct bpf_object *obj)
+int bpf_object__load_xattr(struct bpf_object_load_attr *attr)
 {
+	struct bpf_object *obj;
 	int err;
 
+	if (!attr)
+		return -EINVAL;
+	obj = attr->obj;
 	if (!obj)
 		return -EINVAL;
 
@@ -2397,7 +2376,7 @@ int bpf_object__load(struct bpf_object *obj)
 
 	CHECK_ERR(bpf_object__create_maps(obj), err, out);
 	CHECK_ERR(bpf_object__relocate(obj), err, out);
-	CHECK_ERR(bpf_object__load_progs(obj), err, out);
+	CHECK_ERR(bpf_object__load_progs(obj, attr->log_level), err, out);
 
 	return 0;
 out:
@@ -2406,6 +2385,15 @@ out:
 	return err;
 }
 
+int bpf_object__load(struct bpf_object *obj)
+{
+	struct bpf_object_load_attr attr = {
+		.obj = obj,
+	};
+
+	return bpf_object__load_xattr(&attr);
+}
+
 static int check_path(const char *path)
 {
 	char *cp, errmsg[STRERR_BUFSIZE];
@@ -3458,9 +3446,7 @@ bpf_object__find_map_by_offset(struct bpf_object *obj, size_t offset)
 
 long libbpf_get_error(const void *ptr)
 {
-	if (IS_ERR(ptr))
-		return PTR_ERR(ptr);
-	return 0;
+	return PTR_ERR_OR_ZERO(ptr);
 }
 
 int bpf_prog_load(const char *file, enum bpf_prog_type type,
@@ -3521,6 +3507,7 @@ int bpf_prog_load_xattr(const struct bpf_prog_load_attr *attr,
 						      expected_attach_type);
 
 		prog->log_level = attr->log_level;
+		prog->prog_flags = attr->prog_flags;
 		if (!first_prog)
 			first_prog = prog;
 	}
diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h
index c5ff00515ce7..1af0d48178c8 100644
--- a/tools/lib/bpf/libbpf.h
+++ b/tools/lib/bpf/libbpf.h
@@ -89,8 +89,14 @@ LIBBPF_API int bpf_object__unpin_programs(struct bpf_object *obj,
 LIBBPF_API int bpf_object__pin(struct bpf_object *object, const char *path);
 LIBBPF_API void bpf_object__close(struct bpf_object *object);
 
+struct bpf_object_load_attr {
+	struct bpf_object *obj;
+	int log_level;
+};
+
 /* Load/unload object into/from kernel */
 LIBBPF_API int bpf_object__load(struct bpf_object *obj);
+LIBBPF_API int bpf_object__load_xattr(struct bpf_object_load_attr *attr);
 LIBBPF_API int bpf_object__unload(struct bpf_object *obj);
 LIBBPF_API const char *bpf_object__name(struct bpf_object *obj);
 LIBBPF_API unsigned int bpf_object__kversion(struct bpf_object *obj);
@@ -320,6 +326,7 @@ struct bpf_prog_load_attr {
 	enum bpf_attach_type expected_attach_type;
 	int ifindex;
 	int log_level;
+	int prog_flags;
 };
 
 LIBBPF_API int bpf_prog_load_xattr(const struct bpf_prog_load_attr *attr,
diff --git a/tools/lib/bpf/libbpf.map b/tools/lib/bpf/libbpf.map
index 673001787cba..46dcda89df21 100644
--- a/tools/lib/bpf/libbpf.map
+++ b/tools/lib/bpf/libbpf.map
@@ -164,3 +164,12 @@ LIBBPF_0.0.3 {
 		bpf_map_freeze;
 		btf__finalize_data;
 } LIBBPF_0.0.2;
+
+LIBBPF_0.0.4 {
+	global:
+		btf_dump__dump_type;
+		btf_dump__free;
+		btf_dump__new;
+		btf__parse_elf;
+		bpf_object__load_xattr;
+} LIBBPF_0.0.3;
diff --git a/tools/lib/bpf/libbpf_internal.h b/tools/lib/bpf/libbpf_internal.h
index f3025b4d90e1..850f7bdec5cb 100644
--- a/tools/lib/bpf/libbpf_internal.h
+++ b/tools/lib/bpf/libbpf_internal.h
@@ -9,6 +9,8 @@
 #ifndef __LIBBPF_LIBBPF_INTERNAL_H
 #define __LIBBPF_LIBBPF_INTERNAL_H
 
+#include "libbpf.h"
+
 #define BTF_INFO_ENC(kind, kind_flag, vlen) \
 	((!!(kind_flag) << 31) | ((kind) << 24) | ((vlen) & BTF_MAX_VLEN))
 #define BTF_TYPE_ENC(name, info, size_or_type) (name), (info), (size_or_type)
diff --git a/tools/testing/selftests/bpf/.gitignore b/tools/testing/selftests/bpf/.gitignore
index dd5d69529382..7470327edcfe 100644
--- a/tools/testing/selftests/bpf/.gitignore
+++ b/tools/testing/selftests/bpf/.gitignore
@@ -22,6 +22,7 @@ test_lirc_mode2_user
 get_cgroup_id_user
 test_skb_cgroup_id_user
 test_socket_cookie
+test_cgroup_attach
 test_cgroup_storage
 test_select_reuseport
 test_flow_dissector
@@ -35,3 +36,6 @@ test_sysctl
 alu32
 libbpf.pc
 libbpf.so.*
+test_hashmap
+test_btf_dump
+xdping
diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile
index 66f2dca1dee1..2b426ae1cdc9 100644
--- a/tools/testing/selftests/bpf/Makefile
+++ b/tools/testing/selftests/bpf/Makefile
@@ -15,7 +15,9 @@ LLC		?= llc
 LLVM_OBJCOPY	?= llvm-objcopy
 LLVM_READELF	?= llvm-readelf
 BTF_PAHOLE	?= pahole
-CFLAGS += -Wall -O2 -I$(APIDIR) -I$(LIBDIR) -I$(BPFDIR) -I$(GENDIR) $(GENFLAGS) -I../../../include
+CFLAGS += -Wall -O2 -I$(APIDIR) -I$(LIBDIR) -I$(BPFDIR) -I$(GENDIR) $(GENFLAGS) -I../../../include \
+	  -Dbpf_prog_load=bpf_prog_test_load \
+	  -Dbpf_load_program=bpf_test_load_program
 LDLIBS += -lcap -lelf -lrt -lpthread
 
 # Order correspond to 'make run_tests' order
@@ -23,7 +25,8 @@ TEST_GEN_PROGS = test_verifier test_tag test_maps test_lru_map test_lpm_map test
 	test_align test_verifier_log test_dev_cgroup test_tcpbpf_user \
 	test_sock test_btf test_sockmap test_lirc_mode2_user get_cgroup_id_user \
 	test_socket_cookie test_cgroup_storage test_select_reuseport test_section_names \
-	test_netcnt test_tcpnotify_user test_sock_fields test_sysctl
+	test_netcnt test_tcpnotify_user test_sock_fields test_sysctl test_hashmap \
+	test_btf_dump test_cgroup_attach xdping
 
 BPF_OBJ_FILES = $(patsubst %.c,%.o, $(notdir $(wildcard progs/*.c)))
 TEST_GEN_FILES = $(BPF_OBJ_FILES)
@@ -54,7 +57,8 @@ TEST_PROGS := test_kmod.sh \
 	test_lwt_ip_encap.sh \
 	test_tcp_check_syncookie.sh \
 	test_tc_tunnel.sh \
-	test_tc_edt.sh
+	test_tc_edt.sh \
+	test_xdping.sh
 
 TEST_PROGS_EXTENDED := with_addr.sh \
 	with_tunnels.sh \
@@ -78,9 +82,9 @@ $(OUTPUT)/test_maps: map_tests/*.c
 
 BPFOBJ := $(OUTPUT)/libbpf.a
 
-$(TEST_GEN_PROGS): $(BPFOBJ)
+$(TEST_GEN_PROGS): test_stub.o $(BPFOBJ)
 
-$(TEST_GEN_PROGS_EXTENDED): $(OUTPUT)/libbpf.a
+$(TEST_GEN_PROGS_EXTENDED): test_stub.o $(OUTPUT)/libbpf.a
 
 $(OUTPUT)/test_dev_cgroup: cgroup_helpers.c
 $(OUTPUT)/test_skb_cgroup_id_user: cgroup_helpers.c
@@ -96,6 +100,7 @@ $(OUTPUT)/test_cgroup_storage: cgroup_helpers.c
 $(OUTPUT)/test_netcnt: cgroup_helpers.c
 $(OUTPUT)/test_sock_fields: cgroup_helpers.c
 $(OUTPUT)/test_sysctl: cgroup_helpers.c
+$(OUTPUT)/test_cgroup_attach: cgroup_helpers.c
 
 .PHONY: force
 
@@ -176,7 +181,7 @@ $(ALU32_BUILD_DIR)/test_progs_32: test_progs.c $(OUTPUT)/libbpf.a\
 						$(ALU32_BUILD_DIR)/urandom_read
 	$(CC) $(TEST_PROGS_CFLAGS) $(CFLAGS) \
 		-o $(ALU32_BUILD_DIR)/test_progs_32 \
-		test_progs.c trace_helpers.c prog_tests/*.c \
+		test_progs.c test_stub.c trace_helpers.c prog_tests/*.c \
 		$(OUTPUT)/libbpf.a $(LDLIBS)
 
 $(ALU32_BUILD_DIR)/test_progs_32: $(PROG_TESTS_H)
diff --git a/tools/testing/selftests/bpf/bpf_helpers.h b/tools/testing/selftests/bpf/bpf_helpers.h
index 5f6f9e7aba2a..e6d243b7cd74 100644
--- a/tools/testing/selftests/bpf/bpf_helpers.h
+++ b/tools/testing/selftests/bpf/bpf_helpers.h
@@ -8,6 +8,14 @@
  */
 #define SEC(NAME) __attribute__((section(NAME), used))
 
+/* helper macro to print out debug messages */
+#define bpf_printk(fmt, ...)				\
+({							\
+	char ____fmt[] = fmt;				\
+	bpf_trace_printk(____fmt, sizeof(____fmt),	\
+			 ##__VA_ARGS__);		\
+})
+
 /* helper functions called from eBPF programs written in C */
 static void *(*bpf_map_lookup_elem)(void *map, const void *key) =
 	(void *) BPF_FUNC_map_lookup_elem;
@@ -216,6 +224,7 @@ static void *(*bpf_sk_storage_get)(void *map, struct bpf_sock *sk,
 	(void *) BPF_FUNC_sk_storage_get;
 static int (*bpf_sk_storage_delete)(void *map, struct bpf_sock *sk) =
 	(void *)BPF_FUNC_sk_storage_delete;
+static int (*bpf_send_signal)(unsigned sig) = (void *)BPF_FUNC_send_signal;
 
 /* llvm builtin functions that eBPF C program may use to
  * emit BPF_LD_ABS and BPF_LD_IND instructions
diff --git a/tools/testing/selftests/bpf/cgroup_helpers.c b/tools/testing/selftests/bpf/cgroup_helpers.c
index 6692a40a6979..0d89f0396be4 100644
--- a/tools/testing/selftests/bpf/cgroup_helpers.c
+++ b/tools/testing/selftests/bpf/cgroup_helpers.c
@@ -34,6 +34,60 @@
 		 CGROUP_WORK_DIR, path)
 
 /**
+ * enable_all_controllers() - Enable all available cgroup v2 controllers
+ *
+ * Enable all available cgroup v2 controllers in order to increase
+ * the code coverage.
+ *
+ * If successful, 0 is returned.
+ */
+int enable_all_controllers(char *cgroup_path)
+{
+	char path[PATH_MAX + 1];
+	char buf[PATH_MAX];
+	char *c, *c2;
+	int fd, cfd;
+	size_t len;
+
+	snprintf(path, sizeof(path), "%s/cgroup.controllers", cgroup_path);
+	fd = open(path, O_RDONLY);
+	if (fd < 0) {
+		log_err("Opening cgroup.controllers: %s", path);
+		return 1;
+	}
+
+	len = read(fd, buf, sizeof(buf) - 1);
+	if (len < 0) {
+		close(fd);
+		log_err("Reading cgroup.controllers: %s", path);
+		return 1;
+	}
+	buf[len] = 0;
+	close(fd);
+
+	/* No controllers available? We're probably on cgroup v1. */
+	if (len == 0)
+		return 0;
+
+	snprintf(path, sizeof(path), "%s/cgroup.subtree_control", cgroup_path);
+	cfd = open(path, O_RDWR);
+	if (cfd < 0) {
+		log_err("Opening cgroup.subtree_control: %s", path);
+		return 1;
+	}
+
+	for (c = strtok_r(buf, " ", &c2); c; c = strtok_r(NULL, " ", &c2)) {
+		if (dprintf(cfd, "+%s\n", c) <= 0) {
+			log_err("Enabling controller %s: %s", c, path);
+			close(cfd);
+			return 1;
+		}
+	}
+	close(cfd);
+	return 0;
+}
+
+/**
  * setup_cgroup_environment() - Setup the cgroup environment
  *
  * After calling this function, cleanup_cgroup_environment should be called
@@ -71,6 +125,9 @@ int setup_cgroup_environment(void)
 		return 1;
 	}
 
+	if (enable_all_controllers(cgroup_workdir))
+		return 1;
+
 	return 0;
 }
 
diff --git a/tools/testing/selftests/bpf/prog_tests/bpf_verif_scale.c b/tools/testing/selftests/bpf/prog_tests/bpf_verif_scale.c
index b74e2f6e96d0..c0091137074b 100644
--- a/tools/testing/selftests/bpf/prog_tests/bpf_verif_scale.c
+++ b/tools/testing/selftests/bpf/prog_tests/bpf_verif_scale.c
@@ -12,7 +12,7 @@ static int libbpf_debug_print(enum libbpf_print_level level,
 	return vfprintf(stderr, "%s", args);
 }
 
-static int check_load(const char *file)
+static int check_load(const char *file, enum bpf_prog_type type)
 {
 	struct bpf_prog_load_attr attr;
 	struct bpf_object *obj = NULL;
@@ -20,8 +20,9 @@ static int check_load(const char *file)
 
 	memset(&attr, 0, sizeof(struct bpf_prog_load_attr));
 	attr.file = file;
-	attr.prog_type = BPF_PROG_TYPE_SCHED_CLS;
+	attr.prog_type = type;
 	attr.log_level = 4;
+	attr.prog_flags = BPF_F_TEST_RND_HI32;
 	err = bpf_prog_load_xattr(&attr, &obj, &prog_fd);
 	bpf_object__close(obj);
 	if (err)
@@ -31,19 +32,24 @@ static int check_load(const char *file)
 
 void test_bpf_verif_scale(void)
 {
-	const char *file1 = "./test_verif_scale1.o";
-	const char *file2 = "./test_verif_scale2.o";
-	const char *file3 = "./test_verif_scale3.o";
-	int err;
+	const char *scale[] = {
+		"./test_verif_scale1.o", "./test_verif_scale2.o", "./test_verif_scale3.o"
+	};
+	const char *pyperf[] = {
+		"./pyperf50.o",	"./pyperf100.o", "./pyperf180.o"
+	};
+	int err, i;
 
 	if (verifier_stats)
 		libbpf_set_print(libbpf_debug_print);
 
-	err = check_load(file1);
-	err |= check_load(file2);
-	err |= check_load(file3);
-	if (!err)
-		printf("test_verif_scale:OK\n");
-	else
-		printf("test_verif_scale:FAIL\n");
+	for (i = 0; i < ARRAY_SIZE(scale); i++) {
+		err = check_load(scale[i], BPF_PROG_TYPE_SCHED_CLS);
+		printf("test_scale:%s:%s\n", scale[i], err ? "FAIL" : "OK");
+	}
+
+	for (i = 0; i < ARRAY_SIZE(pyperf); i++) {
+		err = check_load(pyperf[i], BPF_PROG_TYPE_RAW_TRACEPOINT);
+		printf("test_scale:%s:%s\n", pyperf[i], err ? "FAIL" : "OK");
+	}
 }
diff --git a/tools/testing/selftests/bpf/prog_tests/send_signal.c b/tools/testing/selftests/bpf/prog_tests/send_signal.c
new file mode 100644
index 000000000000..67cea1686305
--- /dev/null
+++ b/tools/testing/selftests/bpf/prog_tests/send_signal.c
@@ -0,0 +1,198 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <test_progs.h>
+
+static volatile int sigusr1_received = 0;
+
+static void sigusr1_handler(int signum)
+{
+	sigusr1_received++;
+}
+
+static int test_send_signal_common(struct perf_event_attr *attr,
+				    int prog_type,
+				    const char *test_name)
+{
+	int err = -1, pmu_fd, prog_fd, info_map_fd, status_map_fd;
+	const char *file = "./test_send_signal_kern.o";
+	struct bpf_object *obj = NULL;
+	int pipe_c2p[2], pipe_p2c[2];
+	__u32 key = 0, duration = 0;
+	char buf[256];
+	pid_t pid;
+	__u64 val;
+
+	if (CHECK(pipe(pipe_c2p), test_name,
+		  "pipe pipe_c2p error: %s\n", strerror(errno)))
+		goto no_fork_done;
+
+	if (CHECK(pipe(pipe_p2c), test_name,
+		  "pipe pipe_p2c error: %s\n", strerror(errno))) {
+		close(pipe_c2p[0]);
+		close(pipe_c2p[1]);
+		goto no_fork_done;
+	}
+
+	pid = fork();
+	if (CHECK(pid < 0, test_name, "fork error: %s\n", strerror(errno))) {
+		close(pipe_c2p[0]);
+		close(pipe_c2p[1]);
+		close(pipe_p2c[0]);
+		close(pipe_p2c[1]);
+		goto no_fork_done;
+	}
+
+	if (pid == 0) {
+		/* install signal handler and notify parent */
+		signal(SIGUSR1, sigusr1_handler);
+
+		close(pipe_c2p[0]); /* close read */
+		close(pipe_p2c[1]); /* close write */
+
+		/* notify parent signal handler is installed */
+		write(pipe_c2p[1], buf, 1);
+
+		/* make sure parent enabled bpf program to send_signal */
+		read(pipe_p2c[0], buf, 1);
+
+		/* wait a little for signal handler */
+		sleep(1);
+
+		if (sigusr1_received)
+			write(pipe_c2p[1], "2", 1);
+		else
+			write(pipe_c2p[1], "0", 1);
+
+		/* wait for parent notification and exit */
+		read(pipe_p2c[0], buf, 1);
+
+		close(pipe_c2p[1]);
+		close(pipe_p2c[0]);
+		exit(0);
+	}
+
+	close(pipe_c2p[1]); /* close write */
+	close(pipe_p2c[0]); /* close read */
+
+	err = bpf_prog_load(file, prog_type, &obj, &prog_fd);
+	if (CHECK(err < 0, test_name, "bpf_prog_load error: %s\n",
+		  strerror(errno)))
+		goto prog_load_failure;
+
+	pmu_fd = syscall(__NR_perf_event_open, attr, pid, -1,
+			 -1 /* group id */, 0 /* flags */);
+	if (CHECK(pmu_fd < 0, test_name, "perf_event_open error: %s\n",
+		  strerror(errno))) {
+		err = -1;
+		goto close_prog;
+	}
+
+	err = ioctl(pmu_fd, PERF_EVENT_IOC_ENABLE, 0);
+	if (CHECK(err < 0, test_name, "ioctl perf_event_ioc_enable error: %s\n",
+		  strerror(errno)))
+		goto disable_pmu;
+
+	err = ioctl(pmu_fd, PERF_EVENT_IOC_SET_BPF, prog_fd);
+	if (CHECK(err < 0, test_name, "ioctl perf_event_ioc_set_bpf error: %s\n",
+		  strerror(errno)))
+		goto disable_pmu;
+
+	err = -1;
+	info_map_fd = bpf_object__find_map_fd_by_name(obj, "info_map");
+	if (CHECK(info_map_fd < 0, test_name, "find map %s error\n", "info_map"))
+		goto disable_pmu;
+
+	status_map_fd = bpf_object__find_map_fd_by_name(obj, "status_map");
+	if (CHECK(status_map_fd < 0, test_name, "find map %s error\n", "status_map"))
+		goto disable_pmu;
+
+	/* wait until child signal handler installed */
+	read(pipe_c2p[0], buf, 1);
+
+	/* trigger the bpf send_signal */
+	key = 0;
+	val = (((__u64)(SIGUSR1)) << 32) | pid;
+	bpf_map_update_elem(info_map_fd, &key, &val, 0);
+
+	/* notify child that bpf program can send_signal now */
+	write(pipe_p2c[1], buf, 1);
+
+	/* wait for result */
+	err = read(pipe_c2p[0], buf, 1);
+	if (CHECK(err < 0, test_name, "reading pipe error: %s\n", strerror(errno)))
+		goto disable_pmu;
+	if (CHECK(err == 0, test_name, "reading pipe error: size 0\n")) {
+		err = -1;
+		goto disable_pmu;
+	}
+
+	err = CHECK(buf[0] != '2', test_name, "incorrect result\n");
+
+	/* notify child safe to exit */
+	write(pipe_p2c[1], buf, 1);
+
+disable_pmu:
+	close(pmu_fd);
+close_prog:
+	bpf_object__close(obj);
+prog_load_failure:
+	close(pipe_c2p[0]);
+	close(pipe_p2c[1]);
+	wait(NULL);
+no_fork_done:
+	return err;
+}
+
+static int test_send_signal_tracepoint(void)
+{
+	const char *id_path = "/sys/kernel/debug/tracing/events/syscalls/sys_enter_nanosleep/id";
+	struct perf_event_attr attr = {
+		.type = PERF_TYPE_TRACEPOINT,
+		.sample_type = PERF_SAMPLE_RAW | PERF_SAMPLE_CALLCHAIN,
+		.sample_period = 1,
+		.wakeup_events = 1,
+	};
+	__u32 duration = 0;
+	int bytes, efd;
+	char buf[256];
+
+	efd = open(id_path, O_RDONLY, 0);
+	if (CHECK(efd < 0, "tracepoint",
+		  "open syscalls/sys_enter_nanosleep/id failure: %s\n",
+		  strerror(errno)))
+		return -1;
+
+	bytes = read(efd, buf, sizeof(buf));
+	close(efd);
+	if (CHECK(bytes <= 0 || bytes >= sizeof(buf), "tracepoint",
+		  "read syscalls/sys_enter_nanosleep/id failure: %s\n",
+		  strerror(errno)))
+		return -1;
+
+	attr.config = strtol(buf, NULL, 0);
+
+	return test_send_signal_common(&attr, BPF_PROG_TYPE_TRACEPOINT, "tracepoint");
+}
+
+static int test_send_signal_nmi(void)
+{
+	struct perf_event_attr attr = {
+		.sample_freq = 50,
+		.freq = 1,
+		.type = PERF_TYPE_HARDWARE,
+		.config = PERF_COUNT_HW_CPU_CYCLES,
+	};
+
+	return test_send_signal_common(&attr, BPF_PROG_TYPE_PERF_EVENT, "perf_event");
+}
+
+void test_send_signal(void)
+{
+	int ret = 0;
+
+	ret |= test_send_signal_tracepoint();
+	ret |= test_send_signal_nmi();
+	if (!ret)
+		printf("test_send_signal:OK\n");
+	else
+		printf("test_send_signal:FAIL\n");
+}
diff --git a/tools/testing/selftests/bpf/progs/btf_dump_test_case_bitfields.c b/tools/testing/selftests/bpf/progs/btf_dump_test_case_bitfields.c
new file mode 100644
index 000000000000..8f44767a75fa
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/btf_dump_test_case_bitfields.c
@@ -0,0 +1,92 @@
+// SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
+
+/*
+ * BTF-to-C dumper tests for bitfield.
+ *
+ * Copyright (c) 2019 Facebook
+ */
+#include <stdbool.h>
+
+/* ----- START-EXPECTED-OUTPUT ----- */
+/*
+ *struct bitfields_only_mixed_types {
+ *	int a: 3;
+ *	long int b: 2;
+ *	_Bool c: 1;
+ *	enum {
+ *		A = 0,
+ *		B = 1,
+ *	} d: 1;
+ *	short e: 5;
+ *	int: 20;
+ *	unsigned int f: 30;
+ *};
+ *
+ */
+/* ------ END-EXPECTED-OUTPUT ------ */
+
+struct bitfields_only_mixed_types {
+	int a: 3;
+	long int b: 2;
+	bool c: 1; /* it's really a _Bool type */
+	enum {
+		A, /* A = 0, dumper is very explicit */
+		B, /* B = 1, same */
+	} d: 1;
+	short e: 5;
+	/* 20-bit padding here */
+	unsigned f: 30; /* this gets aligned on 4-byte boundary */
+};
+
+/* ----- START-EXPECTED-OUTPUT ----- */
+/*
+ *struct bitfield_mixed_with_others {
+ *	char: 4;
+ *	int a: 4;
+ *	short b;
+ *	long int c;
+ *	long int d: 8;
+ *	int e;
+ *	int f;
+ *};
+ *
+ */
+/* ------ END-EXPECTED-OUTPUT ------ */
+struct bitfield_mixed_with_others {
+	long: 4; /* char is enough as a backing field */
+	int a: 4;
+	/* 8-bit implicit padding */
+	short b; /* combined with previous bitfield */
+	/* 4 more bytes of implicit padding */
+	long c;
+	long d: 8;
+	/* 24 bits implicit padding */
+	int e; /* combined with previous bitfield */
+	int f;
+	/* 4 bytes of padding */
+};
+
+/* ----- START-EXPECTED-OUTPUT ----- */
+/*
+ *struct bitfield_flushed {
+ *	int a: 4;
+ *	long: 60;
+ *	long int b: 16;
+ *};
+ *
+ */
+/* ------ END-EXPECTED-OUTPUT ------ */
+struct bitfield_flushed {
+	int a: 4;
+	long: 0; /* flush until next natural alignment boundary */
+	long b: 16;
+};
+
+int f(struct {
+	struct bitfields_only_mixed_types _1;
+	struct bitfield_mixed_with_others _2;
+	struct bitfield_flushed _3;
+} *_)
+{
+	return 0;
+}
diff --git a/tools/testing/selftests/bpf/progs/btf_dump_test_case_multidim.c b/tools/testing/selftests/bpf/progs/btf_dump_test_case_multidim.c
new file mode 100644
index 000000000000..ba97165bdb28
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/btf_dump_test_case_multidim.c
@@ -0,0 +1,35 @@
+// SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
+
+/*
+ * BTF-to-C dumper test for multi-dimensional array output.
+ *
+ * Copyright (c) 2019 Facebook
+ */
+/* ----- START-EXPECTED-OUTPUT ----- */
+typedef int arr_t[2];
+
+typedef int multiarr_t[3][4][5];
+
+typedef int *ptr_arr_t[6];
+
+typedef int *ptr_multiarr_t[7][8][9][10];
+
+typedef int * (*fn_ptr_arr_t[11])();
+
+typedef int * (*fn_ptr_multiarr_t[12][13])();
+
+struct root_struct {
+	arr_t _1;
+	multiarr_t _2;
+	ptr_arr_t _3;
+	ptr_multiarr_t _4;
+	fn_ptr_arr_t _5;
+	fn_ptr_multiarr_t _6;
+};
+
+/* ------ END-EXPECTED-OUTPUT ------ */
+
+int f(struct root_struct *s)
+{
+	return 0;
+}
diff --git a/tools/testing/selftests/bpf/progs/btf_dump_test_case_namespacing.c b/tools/testing/selftests/bpf/progs/btf_dump_test_case_namespacing.c
new file mode 100644
index 000000000000..92a4ad428710
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/btf_dump_test_case_namespacing.c
@@ -0,0 +1,73 @@
+// SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
+
+/*
+ * BTF-to-C dumper test validating no name versioning happens between
+ * independent C namespaces (struct/union/enum vs typedef/enum values).
+ *
+ * Copyright (c) 2019 Facebook
+ */
+/* ----- START-EXPECTED-OUTPUT ----- */
+struct S {
+	int S;
+	int U;
+};
+
+typedef struct S S;
+
+union U {
+	int S;
+	int U;
+};
+
+typedef union U U;
+
+enum E {
+	V = 0,
+};
+
+typedef enum E E;
+
+struct A {};
+
+union B {};
+
+enum C {
+	A = 1,
+	B = 2,
+	C = 3,
+};
+
+struct X {};
+
+union Y {};
+
+enum Z;
+
+typedef int X;
+
+typedef int Y;
+
+typedef int Z;
+
+/*------ END-EXPECTED-OUTPUT ------ */
+
+int f(struct {
+	struct S _1;
+	S _2;
+	union U _3;
+	U _4;
+	enum E _5;
+	E _6;
+	struct A a;
+	union B b;
+	enum C c;
+	struct X x;
+	union Y y;
+	enum Z *z;
+	X xx;
+	Y yy;
+	Z zz;
+} *_)
+{
+	return 0;
+}
diff --git a/tools/testing/selftests/bpf/progs/btf_dump_test_case_ordering.c b/tools/testing/selftests/bpf/progs/btf_dump_test_case_ordering.c
new file mode 100644
index 000000000000..7c95702ee4cb
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/btf_dump_test_case_ordering.c
@@ -0,0 +1,63 @@
+// SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
+
+/*
+ * BTF-to-C dumper test for topological sorting of dependent structs.
+ *
+ * Copyright (c) 2019 Facebook
+ */
+/* ----- START-EXPECTED-OUTPUT ----- */
+struct s1 {};
+
+struct s3;
+
+struct s4;
+
+struct s2 {
+	struct s2 *s2;
+	struct s3 *s3;
+	struct s4 *s4;
+};
+
+struct s3 {
+	struct s1 s1;
+	struct s2 s2;
+};
+
+struct s4 {
+	struct s1 s1;
+	struct s3 s3;
+};
+
+struct list_head {
+	struct list_head *next;
+	struct list_head *prev;
+};
+
+struct hlist_node {
+	struct hlist_node *next;
+	struct hlist_node **pprev;
+};
+
+struct hlist_head {
+	struct hlist_node *first;
+};
+
+struct callback_head {
+	struct callback_head *next;
+	void (*func)(struct callback_head *);
+};
+
+struct root_struct {
+	struct s4 s4;
+	struct list_head l;
+	struct hlist_node n;
+	struct hlist_head h;
+	struct callback_head cb;
+};
+
+/*------ END-EXPECTED-OUTPUT ------ */
+
+int f(struct root_struct *root)
+{
+	return 0;
+}
diff --git a/tools/testing/selftests/bpf/progs/btf_dump_test_case_packing.c b/tools/testing/selftests/bpf/progs/btf_dump_test_case_packing.c
new file mode 100644
index 000000000000..1cef3bec1dc7
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/btf_dump_test_case_packing.c
@@ -0,0 +1,75 @@
+// SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
+
+/*
+ * BTF-to-C dumper tests for struct packing determination.
+ *
+ * Copyright (c) 2019 Facebook
+ */
+/* ----- START-EXPECTED-OUTPUT ----- */
+struct packed_trailing_space {
+	int a;
+	short b;
+} __attribute__((packed));
+
+struct non_packed_trailing_space {
+	int a;
+	short b;
+};
+
+struct packed_fields {
+	short a;
+	int b;
+} __attribute__((packed));
+
+struct non_packed_fields {
+	short a;
+	int b;
+};
+
+struct nested_packed {
+	char: 4;
+	int a: 4;
+	long int b;
+	struct {
+		char c;
+		int d;
+	} __attribute__((packed)) e;
+} __attribute__((packed));
+
+union union_is_never_packed {
+	int a: 4;
+	char b;
+	char c: 1;
+};
+
+union union_does_not_need_packing {
+	struct {
+		long int a;
+		int b;
+	} __attribute__((packed));
+	int c;
+};
+
+union jump_code_union {
+	char code[5];
+	struct {
+		char jump;
+		int offset;
+	} __attribute__((packed));
+};
+
+/*------ END-EXPECTED-OUTPUT ------ */
+
+int f(struct {
+	struct packed_trailing_space _1;
+	struct non_packed_trailing_space _2;
+	struct packed_fields _3;
+	struct non_packed_fields _4;
+	struct nested_packed _5;
+	union union_is_never_packed _6;
+	union union_does_not_need_packing _7;
+	union jump_code_union _8;
+} *_)
+{
+	return 0;
+}
diff --git a/tools/testing/selftests/bpf/progs/btf_dump_test_case_padding.c b/tools/testing/selftests/bpf/progs/btf_dump_test_case_padding.c
new file mode 100644
index 000000000000..3a62119c7498
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/btf_dump_test_case_padding.c
@@ -0,0 +1,111 @@
+// SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
+
+/*
+ * BTF-to-C dumper tests for implicit and explicit padding between fields and
+ * at the end of a struct.
+ *
+ * Copyright (c) 2019 Facebook
+ */
+/* ----- START-EXPECTED-OUTPUT ----- */
+struct padded_implicitly {
+	int a;
+	long int b;
+	char c;
+};
+
+/* ------ END-EXPECTED-OUTPUT ------ */
+
+/* ----- START-EXPECTED-OUTPUT ----- */
+/*
+ *struct padded_explicitly {
+ *	int a;
+ *	int: 32;
+ *	int b;
+ *};
+ *
+ */
+/* ------ END-EXPECTED-OUTPUT ------ */
+
+struct padded_explicitly {
+	int a;
+	int: 1; /* algo will explicitly pad with full 32 bits here */
+	int b;
+};
+
+/* ----- START-EXPECTED-OUTPUT ----- */
+/*
+ *struct padded_a_lot {
+ *	int a;
+ *	long: 32;
+ *	long: 64;
+ *	long: 64;
+ *	int b;
+ *};
+ *
+ */
+/* ------ END-EXPECTED-OUTPUT ------ */
+
+struct padded_a_lot {
+	int a;
+	/* 32 bit of implicit padding here, which algo will make explicit */
+	long: 64;
+	long: 64;
+	int b;
+};
+
+/* ----- START-EXPECTED-OUTPUT ----- */
+/*
+ *struct padded_cache_line {
+ *	int a;
+ *	long: 32;
+ *	long: 64;
+ *	long: 64;
+ *	long: 64;
+ *	int b;
+ *};
+ *
+ */
+/* ------ END-EXPECTED-OUTPUT ------ */
+
+struct padded_cache_line {
+	int a;
+	int b __attribute__((aligned(32)));
+};
+
+/* ----- START-EXPECTED-OUTPUT ----- */
+/*
+ *struct zone_padding {
+ *	char x[0];
+ *};
+ *
+ *struct zone {
+ *	int a;
+ *	short b;
+ *	short: 16;
+ *	struct zone_padding __pad__;
+ *};
+ *
+ */
+/* ------ END-EXPECTED-OUTPUT ------ */
+
+struct zone_padding {
+	char x[0];
+} __attribute__((__aligned__(8)));
+
+struct zone {
+	int a;
+	short b;
+	short: 16;
+	struct zone_padding __pad__;
+};
+
+int f(struct {
+	struct padded_implicitly _1;
+	struct padded_explicitly _2;
+	struct padded_a_lot _3;
+	struct padded_cache_line _4;
+	struct zone _5;
+} *_)
+{
+	return 0;
+}
diff --git a/tools/testing/selftests/bpf/progs/btf_dump_test_case_syntax.c b/tools/testing/selftests/bpf/progs/btf_dump_test_case_syntax.c
new file mode 100644
index 000000000000..d4a02fe44a12
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/btf_dump_test_case_syntax.c
@@ -0,0 +1,229 @@
+// SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
+
+/*
+ * BTF-to-C dumper test for majority of C syntax quirks.
+ *
+ * Copyright (c) 2019 Facebook
+ */
+/* ----- START-EXPECTED-OUTPUT ----- */
+enum e1 {
+	A = 0,
+	B = 1,
+};
+
+enum e2 {
+	C = 100,
+	D = -100,
+	E = 0,
+};
+
+typedef enum e2 e2_t;
+
+typedef enum {
+	F = 0,
+	G = 1,
+	H = 2,
+} e3_t;
+
+typedef int int_t;
+
+typedef volatile const int * volatile const crazy_ptr_t;
+
+typedef int *****we_need_to_go_deeper_ptr_t;
+
+typedef volatile const we_need_to_go_deeper_ptr_t * restrict * volatile * const * restrict volatile * restrict const * volatile const * restrict volatile const how_about_this_ptr_t;
+
+typedef int *ptr_arr_t[10];
+
+typedef void (*fn_ptr1_t)(int);
+
+typedef void (*printf_fn_t)(const char *, ...);
+
+/* ------ END-EXPECTED-OUTPUT ------ */
+/*
+ * While previous function pointers are pretty trivial (C-syntax-level
+ * trivial), the following are deciphered here for future generations:
+ *
+ * - `fn_ptr2_t`: function, taking anonymous struct as a first arg and pointer
+ *   to a function, that takes int and returns int, as a second arg; returning
+ *   a pointer to a const pointer to a char. Equivalent to:
+ *	typedef struct { int a; } s_t;
+ *	typedef int (*fn_t)(int);
+ *	typedef char * const * (*fn_ptr2_t)(s_t, fn_t);
+ *
+ * - `fn_complext_t`: pointer to a function returning struct and accepting
+ *   union and struct. All structs and enum are anonymous and defined inline.
+ *
+ * - `signal_t: pointer to a function accepting a pointer to a function as an
+ *   argument and returning pointer to a function as a result. Sane equivalent:
+ *	typedef void (*signal_handler_t)(int);
+ *	typedef signal_handler_t (*signal_ptr_t)(int, signal_handler_t);
+ *
+ * - fn_ptr_arr1_t: array of pointers to a function accepting pointer to
+ *   a pointer to an int and returning pointer to a char. Easy.
+ *
+ * - fn_ptr_arr2_t: array of const pointers to a function taking no arguments
+ *   and returning a const pointer to a function, that takes pointer to a
+ *   `int -> char *` function and returns pointer to a char. Equivalent:
+ *   typedef char * (*fn_input_t)(int);
+ *   typedef char * (*fn_output_outer_t)(fn_input_t);
+ *   typedef const fn_output_outer_t (* fn_output_inner_t)();
+ *   typedef const fn_output_inner_t fn_ptr_arr2_t[5];
+ */
+/* ----- START-EXPECTED-OUTPUT ----- */
+typedef char * const * (*fn_ptr2_t)(struct {
+	int a;
+}, int (*)(int));
+
+typedef struct {
+	int a;
+	void (*b)(int, struct {
+		int c;
+	}, union {
+		char d;
+		int e[5];
+	});
+} (*fn_complex_t)(union {
+	void *f;
+	char g[16];
+}, struct {
+	int h;
+});
+
+typedef void (* (*signal_t)(int, void (*)(int)))(int);
+
+typedef char * (*fn_ptr_arr1_t[10])(int **);
+
+typedef char * (* const (* const fn_ptr_arr2_t[5])())(char * (*)(int));
+
+struct struct_w_typedefs {
+	int_t a;
+	crazy_ptr_t b;
+	we_need_to_go_deeper_ptr_t c;
+	how_about_this_ptr_t d;
+	ptr_arr_t e;
+	fn_ptr1_t f;
+	printf_fn_t g;
+	fn_ptr2_t h;
+	fn_complex_t i;
+	signal_t j;
+	fn_ptr_arr1_t k;
+	fn_ptr_arr2_t l;
+};
+
+typedef struct {
+	int x;
+	int y;
+	int z;
+} anon_struct_t;
+
+struct struct_fwd;
+
+typedef struct struct_fwd struct_fwd_t;
+
+typedef struct struct_fwd *struct_fwd_ptr_t;
+
+union union_fwd;
+
+typedef union union_fwd union_fwd_t;
+
+typedef union union_fwd *union_fwd_ptr_t;
+
+struct struct_empty {};
+
+struct struct_simple {
+	int a;
+	char b;
+	const int_t *p;
+	struct struct_empty s;
+	enum e2 e;
+	enum {
+		ANON_VAL1 = 1,
+		ANON_VAL2 = 2,
+	} f;
+	int arr1[13];
+	enum e2 arr2[5];
+};
+
+union union_empty {};
+
+union union_simple {
+	void *ptr;
+	int num;
+	int_t num2;
+	union union_empty u;
+};
+
+struct struct_in_struct {
+	struct struct_simple simple;
+	union union_simple also_simple;
+	struct {
+		int a;
+	} not_so_hard_as_well;
+	union {
+		int b;
+		int c;
+	} anon_union_is_good;
+	struct {
+		int d;
+		int e;
+	};
+	union {
+		int f;
+		int g;
+	};
+};
+
+struct struct_with_embedded_stuff {
+	int a;
+	struct {
+		int b;
+		struct {
+			struct struct_with_embedded_stuff *c;
+			const char *d;
+		} e;
+		union {
+			volatile long int f;
+			void * restrict g;
+		};
+	};
+	union {
+		const int_t *h;
+		void (*i)(char, int, void *);
+	} j;
+	enum {
+		K = 100,
+		L = 200,
+	} m;
+	char n[16];
+	struct {
+		char o;
+		int p;
+		void (*q)(int);
+	} r[5];
+	struct struct_in_struct s[10];
+	int t[11];
+};
+
+struct root_struct {
+	enum e1 _1;
+	enum e2 _2;
+	e2_t _2_1;
+	e3_t _2_2;
+	struct struct_w_typedefs _3;
+	anon_struct_t _7;
+	struct struct_fwd *_8;
+	struct_fwd_t *_9;
+	struct_fwd_ptr_t _10;
+	union union_fwd *_11;
+	union_fwd_t *_12;
+	union_fwd_ptr_t _13;
+	struct struct_with_embedded_stuff _14;
+};
+
+/* ------ END-EXPECTED-OUTPUT ------ */
+
+int f(struct root_struct *s)
+{
+	return 0;
+}
diff --git a/tools/testing/selftests/bpf/progs/pyperf.h b/tools/testing/selftests/bpf/progs/pyperf.h
new file mode 100644
index 000000000000..0cc5e4ee90bd
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/pyperf.h
@@ -0,0 +1,268 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (c) 2019 Facebook
+#include <linux/sched.h>
+#include <linux/ptrace.h>
+#include <stdint.h>
+#include <stddef.h>
+#include <stdbool.h>
+#include <linux/bpf.h>
+#include "bpf_helpers.h"
+
+#define FUNCTION_NAME_LEN 64
+#define FILE_NAME_LEN 128
+#define TASK_COMM_LEN 16
+
+typedef struct {
+	int PyThreadState_frame;
+	int PyThreadState_thread;
+	int PyFrameObject_back;
+	int PyFrameObject_code;
+	int PyFrameObject_lineno;
+	int PyCodeObject_filename;
+	int PyCodeObject_name;
+	int String_data;
+	int String_size;
+} OffsetConfig;
+
+typedef struct {
+	uintptr_t current_state_addr;
+	uintptr_t tls_key_addr;
+	OffsetConfig offsets;
+	bool use_tls;
+} PidData;
+
+typedef struct {
+	uint32_t success;
+} Stats;
+
+typedef struct {
+	char name[FUNCTION_NAME_LEN];
+	char file[FILE_NAME_LEN];
+} Symbol;
+
+typedef struct {
+	uint32_t pid;
+	uint32_t tid;
+	char comm[TASK_COMM_LEN];
+	int32_t kernel_stack_id;
+	int32_t user_stack_id;
+	bool thread_current;
+	bool pthread_match;
+	bool stack_complete;
+	int16_t stack_len;
+	int32_t stack[STACK_MAX_LEN];
+
+	int has_meta;
+	int metadata;
+	char dummy_safeguard;
+} Event;
+
+
+struct bpf_elf_map {
+	__u32 type;
+	__u32 size_key;
+	__u32 size_value;
+	__u32 max_elem;
+	__u32 flags;
+};
+
+typedef int pid_t;
+
+typedef struct {
+	void* f_back; // PyFrameObject.f_back, previous frame
+	void* f_code; // PyFrameObject.f_code, pointer to PyCodeObject
+	void* co_filename; // PyCodeObject.co_filename
+	void* co_name; // PyCodeObject.co_name
+} FrameData;
+
+static inline __attribute__((__always_inline__)) void*
+get_thread_state(void* tls_base, PidData* pidData)
+{
+	void* thread_state;
+	int key;
+
+	bpf_probe_read(&key, sizeof(key), (void*)(long)pidData->tls_key_addr);
+	bpf_probe_read(&thread_state, sizeof(thread_state),
+		       tls_base + 0x310 + key * 0x10 + 0x08);
+	return thread_state;
+}
+
+static inline __attribute__((__always_inline__)) bool
+get_frame_data(void* frame_ptr, PidData* pidData, FrameData* frame, Symbol* symbol)
+{
+	// read data from PyFrameObject
+	bpf_probe_read(&frame->f_back,
+		       sizeof(frame->f_back),
+		       frame_ptr + pidData->offsets.PyFrameObject_back);
+	bpf_probe_read(&frame->f_code,
+		       sizeof(frame->f_code),
+		       frame_ptr + pidData->offsets.PyFrameObject_code);
+
+	// read data from PyCodeObject
+	if (!frame->f_code)
+		return false;
+	bpf_probe_read(&frame->co_filename,
+		       sizeof(frame->co_filename),
+		       frame->f_code + pidData->offsets.PyCodeObject_filename);
+	bpf_probe_read(&frame->co_name,
+		       sizeof(frame->co_name),
+		       frame->f_code + pidData->offsets.PyCodeObject_name);
+	// read actual names into symbol
+	if (frame->co_filename)
+		bpf_probe_read_str(&symbol->file,
+				   sizeof(symbol->file),
+				   frame->co_filename + pidData->offsets.String_data);
+	if (frame->co_name)
+		bpf_probe_read_str(&symbol->name,
+				   sizeof(symbol->name),
+				   frame->co_name + pidData->offsets.String_data);
+	return true;
+}
+
+struct bpf_elf_map SEC("maps") pidmap = {
+	.type = BPF_MAP_TYPE_HASH,
+	.size_key = sizeof(int),
+	.size_value = sizeof(PidData),
+	.max_elem = 1,
+};
+
+struct bpf_elf_map SEC("maps") eventmap = {
+	.type = BPF_MAP_TYPE_HASH,
+	.size_key = sizeof(int),
+	.size_value = sizeof(Event),
+	.max_elem = 1,
+};
+
+struct bpf_elf_map SEC("maps") symbolmap = {
+	.type = BPF_MAP_TYPE_HASH,
+	.size_key = sizeof(Symbol),
+	.size_value = sizeof(int),
+	.max_elem = 1,
+};
+
+struct bpf_elf_map SEC("maps") statsmap = {
+	.type = BPF_MAP_TYPE_ARRAY,
+	.size_key = sizeof(Stats),
+	.size_value = sizeof(int),
+	.max_elem = 1,
+};
+
+struct bpf_elf_map SEC("maps") perfmap = {
+	.type = BPF_MAP_TYPE_PERF_EVENT_ARRAY,
+	.size_key = sizeof(int),
+	.size_value = sizeof(int),
+	.max_elem = 32,
+};
+
+struct bpf_elf_map SEC("maps") stackmap = {
+	.type = BPF_MAP_TYPE_STACK_TRACE,
+	.size_key = sizeof(int),
+	.size_value = sizeof(long long) * 127,
+	.max_elem = 1000,
+};
+
+static inline __attribute__((__always_inline__)) int __on_event(struct pt_regs *ctx)
+{
+	uint64_t pid_tgid = bpf_get_current_pid_tgid();
+	pid_t pid = (pid_t)(pid_tgid >> 32);
+	PidData* pidData = bpf_map_lookup_elem(&pidmap, &pid);
+	if (!pidData)
+		return 0;
+
+	int zero = 0;
+	Event* event = bpf_map_lookup_elem(&eventmap, &zero);
+	if (!event)
+		return 0;
+
+	event->pid = pid;
+
+	event->tid = (pid_t)pid_tgid;
+	bpf_get_current_comm(&event->comm, sizeof(event->comm));
+
+	event->user_stack_id = bpf_get_stackid(ctx, &stackmap, BPF_F_USER_STACK);
+	event->kernel_stack_id = bpf_get_stackid(ctx, &stackmap, 0);
+
+	void* thread_state_current = (void*)0;
+	bpf_probe_read(&thread_state_current,
+		       sizeof(thread_state_current),
+		       (void*)(long)pidData->current_state_addr);
+
+	struct task_struct* task = (struct task_struct*)bpf_get_current_task();
+	void* tls_base = (void*)task;
+
+	void* thread_state = pidData->use_tls ? get_thread_state(tls_base, pidData)
+		: thread_state_current;
+	event->thread_current = thread_state == thread_state_current;
+
+	if (pidData->use_tls) {
+		uint64_t pthread_created;
+		uint64_t pthread_self;
+		bpf_probe_read(&pthread_self, sizeof(pthread_self), tls_base + 0x10);
+
+		bpf_probe_read(&pthread_created,
+			       sizeof(pthread_created),
+			       thread_state + pidData->offsets.PyThreadState_thread);
+		event->pthread_match = pthread_created == pthread_self;
+	} else {
+		event->pthread_match = 1;
+	}
+
+	if (event->pthread_match || !pidData->use_tls) {
+		void* frame_ptr;
+		FrameData frame;
+		Symbol sym = {};
+		int cur_cpu = bpf_get_smp_processor_id();
+
+		bpf_probe_read(&frame_ptr,
+			       sizeof(frame_ptr),
+			       thread_state + pidData->offsets.PyThreadState_frame);
+
+		int32_t* symbol_counter = bpf_map_lookup_elem(&symbolmap, &sym);
+		if (symbol_counter == NULL)
+			return 0;
+#pragma unroll
+		/* Unwind python stack */
+		for (int i = 0; i < STACK_MAX_LEN; ++i) {
+			if (frame_ptr && get_frame_data(frame_ptr, pidData, &frame, &sym)) {
+				int32_t new_symbol_id = *symbol_counter * 64 + cur_cpu;
+				int32_t *symbol_id = bpf_map_lookup_elem(&symbolmap, &sym);
+				if (!symbol_id) {
+					bpf_map_update_elem(&symbolmap, &sym, &zero, 0);
+					symbol_id = bpf_map_lookup_elem(&symbolmap, &sym);
+					if (!symbol_id)
+						return 0;
+				}
+				if (*symbol_id == new_symbol_id)
+					(*symbol_counter)++;
+				event->stack[i] = *symbol_id;
+				event->stack_len = i + 1;
+				frame_ptr = frame.f_back;
+			}
+		}
+		event->stack_complete = frame_ptr == NULL;
+	} else {
+		event->stack_complete = 1;
+	}
+
+	Stats* stats = bpf_map_lookup_elem(&statsmap, &zero);
+	if (stats)
+		stats->success++;
+
+	event->has_meta = 0;
+	bpf_perf_event_output(ctx, &perfmap, 0, event, offsetof(Event, metadata));
+	return 0;
+}
+
+SEC("raw_tracepoint/kfree_skb")
+int on_event(struct pt_regs* ctx)
+{
+	int i, ret = 0;
+	ret |= __on_event(ctx);
+	ret |= __on_event(ctx);
+	ret |= __on_event(ctx);
+	ret |= __on_event(ctx);
+	ret |= __on_event(ctx);
+	return ret;
+}
+
+char _license[] SEC("license") = "GPL";
diff --git a/tools/testing/selftests/bpf/progs/pyperf100.c b/tools/testing/selftests/bpf/progs/pyperf100.c
new file mode 100644
index 000000000000..29786325db54
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/pyperf100.c
@@ -0,0 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (c) 2019 Facebook
+#define STACK_MAX_LEN 100
+#include "pyperf.h"
diff --git a/tools/testing/selftests/bpf/progs/pyperf180.c b/tools/testing/selftests/bpf/progs/pyperf180.c
new file mode 100644
index 000000000000..c39f559d3100
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/pyperf180.c
@@ -0,0 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (c) 2019 Facebook
+#define STACK_MAX_LEN 180
+#include "pyperf.h"
diff --git a/tools/testing/selftests/bpf/progs/pyperf50.c b/tools/testing/selftests/bpf/progs/pyperf50.c
new file mode 100644
index 000000000000..ef7ce340a292
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/pyperf50.c
@@ -0,0 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (c) 2019 Facebook
+#define STACK_MAX_LEN 50
+#include "pyperf.h"
diff --git a/tools/testing/selftests/bpf/progs/sockmap_parse_prog.c b/tools/testing/selftests/bpf/progs/sockmap_parse_prog.c
index 0f92858f6226..ed3e4a551c57 100644
--- a/tools/testing/selftests/bpf/progs/sockmap_parse_prog.c
+++ b/tools/testing/selftests/bpf/progs/sockmap_parse_prog.c
@@ -5,13 +5,6 @@
 
 int _version SEC("version") = 1;
 
-#define bpf_printk(fmt, ...)					\
-({								\
-	       char ____fmt[] = fmt;				\
-	       bpf_trace_printk(____fmt, sizeof(____fmt),	\
-				##__VA_ARGS__);			\
-})
-
 SEC("sk_skb1")
 int bpf_prog1(struct __sk_buff *skb)
 {
diff --git a/tools/testing/selftests/bpf/progs/sockmap_tcp_msg_prog.c b/tools/testing/selftests/bpf/progs/sockmap_tcp_msg_prog.c
index 12a7b5c82ed6..65fbfdb6cd3a 100644
--- a/tools/testing/selftests/bpf/progs/sockmap_tcp_msg_prog.c
+++ b/tools/testing/selftests/bpf/progs/sockmap_tcp_msg_prog.c
@@ -5,13 +5,6 @@
 
 int _version SEC("version") = 1;
 
-#define bpf_printk(fmt, ...)					\
-({								\
-	       char ____fmt[] = fmt;				\
-	       bpf_trace_printk(____fmt, sizeof(____fmt),	\
-				##__VA_ARGS__);			\
-})
-
 SEC("sk_msg1")
 int bpf_prog1(struct sk_msg_md *msg)
 {
diff --git a/tools/testing/selftests/bpf/progs/sockmap_verdict_prog.c b/tools/testing/selftests/bpf/progs/sockmap_verdict_prog.c
index 2ce7634a4012..bdc22be46f2e 100644
--- a/tools/testing/selftests/bpf/progs/sockmap_verdict_prog.c
+++ b/tools/testing/selftests/bpf/progs/sockmap_verdict_prog.c
@@ -5,13 +5,6 @@
 
 int _version SEC("version") = 1;
 
-#define bpf_printk(fmt, ...)					\
-({								\
-	       char ____fmt[] = fmt;				\
-	       bpf_trace_printk(____fmt, sizeof(____fmt),	\
-				##__VA_ARGS__);			\
-})
-
 struct bpf_map_def SEC("maps") sock_map_rx = {
 	.type = BPF_MAP_TYPE_SOCKMAP,
 	.key_size = sizeof(int),
diff --git a/tools/testing/selftests/bpf/progs/test_lwt_seg6local.c b/tools/testing/selftests/bpf/progs/test_lwt_seg6local.c
index 0575751bc1bc..7c7cb3177463 100644
--- a/tools/testing/selftests/bpf/progs/test_lwt_seg6local.c
+++ b/tools/testing/selftests/bpf/progs/test_lwt_seg6local.c
@@ -6,13 +6,6 @@
 #include "bpf_helpers.h"
 #include "bpf_endian.h"
 
-#define bpf_printk(fmt, ...)				\
-({							\
-	char ____fmt[] = fmt;				\
-	bpf_trace_printk(____fmt, sizeof(____fmt),	\
-			##__VA_ARGS__);			\
-})
-
 /* Packet parsing state machine helpers. */
 #define cursor_advance(_cursor, _len) \
 	({ void *_tmp = _cursor; _cursor += _len; _tmp; })
diff --git a/tools/testing/selftests/bpf/progs/test_send_signal_kern.c b/tools/testing/selftests/bpf/progs/test_send_signal_kern.c
new file mode 100644
index 000000000000..45a1a1a2c345
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/test_send_signal_kern.c
@@ -0,0 +1,51 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (c) 2019 Facebook
+#include <linux/bpf.h>
+#include <linux/version.h>
+#include "bpf_helpers.h"
+
+struct bpf_map_def SEC("maps") info_map = {
+	.type = BPF_MAP_TYPE_ARRAY,
+	.key_size = sizeof(__u32),
+	.value_size = sizeof(__u64),
+	.max_entries = 1,
+};
+
+BPF_ANNOTATE_KV_PAIR(info_map, __u32, __u64);
+
+struct bpf_map_def SEC("maps") status_map = {
+	.type = BPF_MAP_TYPE_ARRAY,
+	.key_size = sizeof(__u32),
+	.value_size = sizeof(__u64),
+	.max_entries = 1,
+};
+
+BPF_ANNOTATE_KV_PAIR(status_map, __u32, __u64);
+
+SEC("send_signal_demo")
+int bpf_send_signal_test(void *ctx)
+{
+	__u64 *info_val, *status_val;
+	__u32 key = 0, pid, sig;
+	int ret;
+
+	status_val = bpf_map_lookup_elem(&status_map, &key);
+	if (!status_val || *status_val != 0)
+		return 0;
+
+	info_val = bpf_map_lookup_elem(&info_map, &key);
+	if (!info_val || *info_val == 0)
+		return 0;
+
+	sig = *info_val >> 32;
+	pid = *info_val & 0xffffFFFF;
+
+	if ((bpf_get_current_pid_tgid() >> 32) == pid) {
+		ret = bpf_send_signal(sig);
+		if (ret == 0)
+			*status_val = 1;
+	}
+
+	return 0;
+}
+char __license[] SEC("license") = "GPL";
diff --git a/tools/testing/selftests/bpf/progs/test_xdp_noinline.c b/tools/testing/selftests/bpf/progs/test_xdp_noinline.c
index 5e4aac74f9d0..4fe6aaad22a4 100644
--- a/tools/testing/selftests/bpf/progs/test_xdp_noinline.c
+++ b/tools/testing/selftests/bpf/progs/test_xdp_noinline.c
@@ -15,13 +15,6 @@
 #include <linux/udp.h>
 #include "bpf_helpers.h"
 
-#define bpf_printk(fmt, ...)				\
-({							\
-	char ____fmt[] = fmt;				\
-	bpf_trace_printk(____fmt, sizeof(____fmt),	\
-			##__VA_ARGS__);			\
-})
-
 static __u32 rol32(__u32 word, unsigned int shift)
 {
 	return (word << shift) | (word >> ((-shift) & 31));
diff --git a/tools/testing/selftests/bpf/progs/xdping_kern.c b/tools/testing/selftests/bpf/progs/xdping_kern.c
new file mode 100644
index 000000000000..87393e7c667c
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/xdping_kern.c
@@ -0,0 +1,184 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2019, Oracle and/or its affiliates. All rights reserved. */
+
+#define KBUILD_MODNAME "foo"
+#include <stddef.h>
+#include <string.h>
+#include <linux/bpf.h>
+#include <linux/icmp.h>
+#include <linux/in.h>
+#include <linux/if_ether.h>
+#include <linux/if_packet.h>
+#include <linux/if_vlan.h>
+#include <linux/ip.h>
+
+#include "bpf_helpers.h"
+#include "bpf_endian.h"
+
+#include "xdping.h"
+
+struct bpf_map_def SEC("maps") ping_map = {
+	.type = BPF_MAP_TYPE_HASH,
+	.key_size = sizeof(__u32),
+	.value_size = sizeof(struct pinginfo),
+	.max_entries = 256,
+};
+
+static __always_inline void swap_src_dst_mac(void *data)
+{
+	unsigned short *p = data;
+	unsigned short dst[3];
+
+	dst[0] = p[0];
+	dst[1] = p[1];
+	dst[2] = p[2];
+	p[0] = p[3];
+	p[1] = p[4];
+	p[2] = p[5];
+	p[3] = dst[0];
+	p[4] = dst[1];
+	p[5] = dst[2];
+}
+
+static __always_inline __u16 csum_fold_helper(__wsum sum)
+{
+	sum = (sum & 0xffff) + (sum >> 16);
+	return ~((sum & 0xffff) + (sum >> 16));
+}
+
+static __always_inline __u16 ipv4_csum(void *data_start, int data_size)
+{
+	__wsum sum;
+
+	sum = bpf_csum_diff(0, 0, data_start, data_size, 0);
+	return csum_fold_helper(sum);
+}
+
+#define ICMP_ECHO_LEN		64
+
+static __always_inline int icmp_check(struct xdp_md *ctx, int type)
+{
+	void *data_end = (void *)(long)ctx->data_end;
+	void *data = (void *)(long)ctx->data;
+	struct ethhdr *eth = data;
+	struct icmphdr *icmph;
+	struct iphdr *iph;
+
+	if (data + sizeof(*eth) + sizeof(*iph) + ICMP_ECHO_LEN > data_end)
+		return XDP_PASS;
+
+	if (eth->h_proto != bpf_htons(ETH_P_IP))
+		return XDP_PASS;
+
+	iph = data + sizeof(*eth);
+
+	if (iph->protocol != IPPROTO_ICMP)
+		return XDP_PASS;
+
+	if (bpf_ntohs(iph->tot_len) - sizeof(*iph) != ICMP_ECHO_LEN)
+		return XDP_PASS;
+
+	icmph = data + sizeof(*eth) + sizeof(*iph);
+
+	if (icmph->type != type)
+		return XDP_PASS;
+
+	return XDP_TX;
+}
+
+SEC("xdpclient")
+int xdping_client(struct xdp_md *ctx)
+{
+	void *data_end = (void *)(long)ctx->data_end;
+	void *data = (void *)(long)ctx->data;
+	struct pinginfo *pinginfo = NULL;
+	struct ethhdr *eth = data;
+	struct icmphdr *icmph;
+	struct iphdr *iph;
+	__u64 recvtime;
+	__be32 raddr;
+	__be16 seq;
+	int ret;
+	__u8 i;
+
+	ret = icmp_check(ctx, ICMP_ECHOREPLY);
+
+	if (ret != XDP_TX)
+		return ret;
+
+	iph = data + sizeof(*eth);
+	icmph = data + sizeof(*eth) + sizeof(*iph);
+	raddr = iph->saddr;
+
+	/* Record time reply received. */
+	recvtime = bpf_ktime_get_ns();
+	pinginfo = bpf_map_lookup_elem(&ping_map, &raddr);
+	if (!pinginfo || pinginfo->seq != icmph->un.echo.sequence)
+		return XDP_PASS;
+
+	if (pinginfo->start) {
+#pragma clang loop unroll(full)
+		for (i = 0; i < XDPING_MAX_COUNT; i++) {
+			if (pinginfo->times[i] == 0)
+				break;
+		}
+		/* verifier is fussy here... */
+		if (i < XDPING_MAX_COUNT) {
+			pinginfo->times[i] = recvtime -
+					     pinginfo->start;
+			pinginfo->start = 0;
+			i++;
+		}
+		/* No more space for values? */
+		if (i == pinginfo->count || i == XDPING_MAX_COUNT)
+			return XDP_PASS;
+	}
+
+	/* Now convert reply back into echo request. */
+	swap_src_dst_mac(data);
+	iph->saddr = iph->daddr;
+	iph->daddr = raddr;
+	icmph->type = ICMP_ECHO;
+	seq = bpf_htons(bpf_ntohs(icmph->un.echo.sequence) + 1);
+	icmph->un.echo.sequence = seq;
+	icmph->checksum = 0;
+	icmph->checksum = ipv4_csum(icmph, ICMP_ECHO_LEN);
+
+	pinginfo->seq = seq;
+	pinginfo->start = bpf_ktime_get_ns();
+
+	return XDP_TX;
+}
+
+SEC("xdpserver")
+int xdping_server(struct xdp_md *ctx)
+{
+	void *data_end = (void *)(long)ctx->data_end;
+	void *data = (void *)(long)ctx->data;
+	struct ethhdr *eth = data;
+	struct icmphdr *icmph;
+	struct iphdr *iph;
+	__be32 raddr;
+	int ret;
+
+	ret = icmp_check(ctx, ICMP_ECHO);
+
+	if (ret != XDP_TX)
+		return ret;
+
+	iph = data + sizeof(*eth);
+	icmph = data + sizeof(*eth) + sizeof(*iph);
+	raddr = iph->saddr;
+
+	/* Now convert request into echo reply. */
+	swap_src_dst_mac(data);
+	iph->saddr = iph->daddr;
+	iph->daddr = raddr;
+	icmph->type = ICMP_ECHOREPLY;
+	icmph->checksum = 0;
+	icmph->checksum = ipv4_csum(icmph, ICMP_ECHO_LEN);
+
+	return XDP_TX;
+}
+
+char _license[] SEC("license") = "GPL";
diff --git a/tools/testing/selftests/bpf/test_btf.c b/tools/testing/selftests/bpf/test_btf.c
index 42c1ce988945..289daf54dec4 100644
--- a/tools/testing/selftests/bpf/test_btf.c
+++ b/tools/testing/selftests/bpf/test_btf.c
@@ -4025,62 +4025,13 @@ static struct btf_file_test file_tests[] = {
 },
 };
 
-static int file_has_btf_elf(const char *fn, bool *has_btf_ext)
-{
-	Elf_Scn *scn = NULL;
-	GElf_Ehdr ehdr;
-	int ret = 0;
-	int elf_fd;
-	Elf *elf;
-
-	if (CHECK(elf_version(EV_CURRENT) == EV_NONE,
-		  "elf_version(EV_CURRENT) == EV_NONE"))
-		return -1;
-
-	elf_fd = open(fn, O_RDONLY);
-	if (CHECK(elf_fd == -1, "open(%s): errno:%d", fn, errno))
-		return -1;
-
-	elf = elf_begin(elf_fd, ELF_C_READ, NULL);
-	if (CHECK(!elf, "elf_begin(%s): %s", fn, elf_errmsg(elf_errno()))) {
-		ret = -1;
-		goto done;
-	}
-
-	if (CHECK(!gelf_getehdr(elf, &ehdr), "!gelf_getehdr(%s)", fn)) {
-		ret = -1;
-		goto done;
-	}
-
-	while ((scn = elf_nextscn(elf, scn))) {
-		const char *sh_name;
-		GElf_Shdr sh;
-
-		if (CHECK(gelf_getshdr(scn, &sh) != &sh,
-			  "file:%s gelf_getshdr != &sh", 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;
-		if (!strcmp(sh_name, BTF_EXT_ELF_SEC))
-			*has_btf_ext = true;
-	}
-
-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];
 	const char *expected_fnames[] = {"_dummy_tracepoint",
 					 "test_long_fname_1",
 					 "test_long_fname_2"};
+	struct btf_ext *btf_ext = NULL;
 	struct bpf_prog_info info = {};
 	struct bpf_object *obj = NULL;
 	struct bpf_func_info *finfo;
@@ -4095,15 +4046,19 @@ static int do_test_file(unsigned int test_num)
 	fprintf(stderr, "BTF libbpf test[%u] (%s): ", test_num,
 		test->file);
 
-	err = file_has_btf_elf(test->file, &has_btf_ext);
-	if (err == -1)
-		return err;
-
-	if (err == 0) {
-		fprintf(stderr, "SKIP. No ELF %s found", BTF_ELF_SEC);
-		skip_cnt++;
-		return 0;
+	btf = btf__parse_elf(test->file, &btf_ext);
+	if (IS_ERR(btf)) {
+		if (PTR_ERR(btf) == -ENOENT) {
+			fprintf(stderr, "SKIP. No ELF %s found", BTF_ELF_SEC);
+			skip_cnt++;
+			return 0;
+		}
+		return PTR_ERR(btf);
 	}
+	btf__free(btf);
+
+	has_btf_ext = btf_ext != NULL;
+	btf_ext__free(btf_ext);
 
 	obj = bpf_object__open(test->file);
 	if (CHECK(IS_ERR(obj), "obj: %ld", PTR_ERR(obj)))
diff --git a/tools/testing/selftests/bpf/test_btf_dump.c b/tools/testing/selftests/bpf/test_btf_dump.c
new file mode 100644
index 000000000000..8f850823d35f
--- /dev/null
+++ b/tools/testing/selftests/bpf/test_btf_dump.c
@@ -0,0 +1,143 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <errno.h>
+#include <linux/err.h>
+#include <btf.h>
+
+#define CHECK(condition, format...) ({					\
+	int __ret = !!(condition);					\
+	if (__ret) {							\
+		fprintf(stderr, "%s:%d:FAIL ", __func__, __LINE__);	\
+		fprintf(stderr, format);				\
+	}								\
+	__ret;								\
+})
+
+void btf_dump_printf(void *ctx, const char *fmt, va_list args)
+{
+	vfprintf(ctx, fmt, args);
+}
+
+struct btf_dump_test_case {
+	const char *name;
+	struct btf_dump_opts opts;
+} btf_dump_test_cases[] = {
+	{.name = "btf_dump_test_case_syntax", .opts = {}},
+	{.name = "btf_dump_test_case_ordering", .opts = {}},
+	{.name = "btf_dump_test_case_padding", .opts = {}},
+	{.name = "btf_dump_test_case_packing", .opts = {}},
+	{.name = "btf_dump_test_case_bitfields", .opts = {}},
+	{.name = "btf_dump_test_case_multidim", .opts = {}},
+	{.name = "btf_dump_test_case_namespacing", .opts = {}},
+};
+
+static int btf_dump_all_types(const struct btf *btf,
+			      const struct btf_dump_opts *opts)
+{
+	size_t type_cnt = btf__get_nr_types(btf);
+	struct btf_dump *d;
+	int err = 0, id;
+
+	d = btf_dump__new(btf, NULL, opts, btf_dump_printf);
+	if (IS_ERR(d))
+		return PTR_ERR(d);
+
+	for (id = 1; id <= type_cnt; id++) {
+		err = btf_dump__dump_type(d, id);
+		if (err)
+			goto done;
+	}
+
+done:
+	btf_dump__free(d);
+	return err;
+}
+
+int test_btf_dump_case(int n, struct btf_dump_test_case *test_case)
+{
+	char test_file[256], out_file[256], diff_cmd[1024];
+	struct btf *btf = NULL;
+	int err = 0, fd = -1;
+	FILE *f = NULL;
+
+	fprintf(stderr, "Test case #%d (%s): ", n, test_case->name);
+
+	snprintf(test_file, sizeof(test_file), "%s.o", test_case->name);
+
+	btf = btf__parse_elf(test_file, NULL);
+	if (CHECK(IS_ERR(btf),
+	    "failed to load test BTF: %ld\n", PTR_ERR(btf))) {
+		err = -PTR_ERR(btf);
+		btf = NULL;
+		goto done;
+	}
+
+	snprintf(out_file, sizeof(out_file),
+		 "/tmp/%s.output.XXXXXX", test_case->name);
+	fd = mkstemp(out_file);
+	if (CHECK(fd < 0, "failed to create temp output file: %d\n", fd)) {
+		err = fd;
+		goto done;
+	}
+	f = fdopen(fd, "w");
+	if (CHECK(f == NULL, "failed to open temp output file: %s(%d)\n",
+		  strerror(errno), errno)) {
+		close(fd);
+		goto done;
+	}
+
+	test_case->opts.ctx = f;
+	err = btf_dump_all_types(btf, &test_case->opts);
+	fclose(f);
+	close(fd);
+	if (CHECK(err, "failure during C dumping: %d\n", err)) {
+		goto done;
+	}
+
+	snprintf(test_file, sizeof(test_file), "progs/%s.c", test_case->name);
+	/*
+	 * Diff test output and expected test output, contained between
+	 * START-EXPECTED-OUTPUT and END-EXPECTED-OUTPUT lines in test case.
+	 * For expected output lines, everything before '*' is stripped out.
+	 * Also lines containing comment start and comment end markers are
+	 * ignored. 
+	 */
+	snprintf(diff_cmd, sizeof(diff_cmd),
+		 "awk '/START-EXPECTED-OUTPUT/{out=1;next} "
+		 "/END-EXPECTED-OUTPUT/{out=0} "
+		 "/\\/\\*|\\*\\//{next} " /* ignore comment start/end lines */
+		 "out {sub(/^[ \\t]*\\*/, \"\"); print}' '%s' | diff -u - '%s'",
+		 test_file, out_file);
+	err = system(diff_cmd);
+	if (CHECK(err,
+		  "differing test output, output=%s, err=%d, diff cmd:\n%s\n",
+		  out_file, err, diff_cmd))
+		goto done;
+
+	remove(out_file);
+	fprintf(stderr, "OK\n");
+
+done:
+	btf__free(btf);
+	return err;
+}
+
+int main() {
+	int test_case_cnt, i, err, failed = 0;
+
+	test_case_cnt = sizeof(btf_dump_test_cases) /
+			sizeof(btf_dump_test_cases[0]);
+
+	for (i = 0; i < test_case_cnt; i++) {
+		err = test_btf_dump_case(i, &btf_dump_test_cases[i]);
+		if (err)
+			failed++;
+	}
+
+	fprintf(stderr, "%d tests succeeded, %d tests failed.\n",
+		test_case_cnt - failed, failed);
+
+	return failed;
+}
diff --git a/tools/testing/selftests/bpf/test_cgroup_attach.c b/tools/testing/selftests/bpf/test_cgroup_attach.c
new file mode 100644
index 000000000000..7671909ee1cb
--- /dev/null
+++ b/tools/testing/selftests/bpf/test_cgroup_attach.c
@@ -0,0 +1,571 @@
+// SPDX-License-Identifier: GPL-2.0
+
+/* eBPF example program:
+ *
+ * - Creates arraymap in kernel with 4 bytes keys and 8 byte values
+ *
+ * - Loads eBPF program
+ *
+ *   The eBPF program accesses the map passed in to store two pieces of
+ *   information. The number of invocations of the program, which maps
+ *   to the number of packets received, is stored to key 0. Key 1 is
+ *   incremented on each iteration by the number of bytes stored in
+ *   the skb. The program also stores the number of received bytes
+ *   in the cgroup storage.
+ *
+ * - Attaches the new program to a cgroup using BPF_PROG_ATTACH
+ *
+ * - Every second, reads map[0] and map[1] to see how many bytes and
+ *   packets were seen on any socket of tasks in the given cgroup.
+ */
+
+#define _GNU_SOURCE
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <assert.h>
+#include <sys/resource.h>
+#include <sys/time.h>
+#include <unistd.h>
+#include <linux/filter.h>
+
+#include <linux/bpf.h>
+#include <bpf/bpf.h>
+
+#include "bpf_util.h"
+#include "bpf_rlimit.h"
+#include "cgroup_helpers.h"
+
+#define FOO		"/foo"
+#define BAR		"/foo/bar/"
+#define PING_CMD	"ping -q -c1 -w1 127.0.0.1 > /dev/null"
+
+char bpf_log_buf[BPF_LOG_BUF_SIZE];
+
+#ifdef DEBUG
+#define debug(args...) printf(args)
+#else
+#define debug(args...)
+#endif
+
+static int prog_load(int verdict)
+{
+	int ret;
+	struct bpf_insn prog[] = {
+		BPF_MOV64_IMM(BPF_REG_0, verdict), /* r0 = verdict */
+		BPF_EXIT_INSN(),
+	};
+	size_t insns_cnt = sizeof(prog) / sizeof(struct bpf_insn);
+
+	ret = bpf_load_program(BPF_PROG_TYPE_CGROUP_SKB,
+			       prog, insns_cnt, "GPL", 0,
+			       bpf_log_buf, BPF_LOG_BUF_SIZE);
+
+	if (ret < 0) {
+		log_err("Loading program");
+		printf("Output from verifier:\n%s\n-------\n", bpf_log_buf);
+		return 0;
+	}
+	return ret;
+}
+
+static int test_foo_bar(void)
+{
+	int drop_prog, allow_prog, foo = 0, bar = 0, rc = 0;
+
+	allow_prog = prog_load(1);
+	if (!allow_prog)
+		goto err;
+
+	drop_prog = prog_load(0);
+	if (!drop_prog)
+		goto err;
+
+	if (setup_cgroup_environment())
+		goto err;
+
+	/* Create cgroup /foo, get fd, and join it */
+	foo = create_and_get_cgroup(FOO);
+	if (foo < 0)
+		goto err;
+
+	if (join_cgroup(FOO))
+		goto err;
+
+	if (bpf_prog_attach(drop_prog, foo, BPF_CGROUP_INET_EGRESS,
+			    BPF_F_ALLOW_OVERRIDE)) {
+		log_err("Attaching prog to /foo");
+		goto err;
+	}
+
+	debug("Attached DROP prog. This ping in cgroup /foo should fail...\n");
+	assert(system(PING_CMD) != 0);
+
+	/* Create cgroup /foo/bar, get fd, and join it */
+	bar = create_and_get_cgroup(BAR);
+	if (bar < 0)
+		goto err;
+
+	if (join_cgroup(BAR))
+		goto err;
+
+	debug("Attached DROP prog. This ping in cgroup /foo/bar should fail...\n");
+	assert(system(PING_CMD) != 0);
+
+	if (bpf_prog_attach(allow_prog, bar, BPF_CGROUP_INET_EGRESS,
+			    BPF_F_ALLOW_OVERRIDE)) {
+		log_err("Attaching prog to /foo/bar");
+		goto err;
+	}
+
+	debug("Attached PASS prog. This ping in cgroup /foo/bar should pass...\n");
+	assert(system(PING_CMD) == 0);
+
+	if (bpf_prog_detach(bar, BPF_CGROUP_INET_EGRESS)) {
+		log_err("Detaching program from /foo/bar");
+		goto err;
+	}
+
+	debug("Detached PASS from /foo/bar while DROP is attached to /foo.\n"
+	       "This ping in cgroup /foo/bar should fail...\n");
+	assert(system(PING_CMD) != 0);
+
+	if (bpf_prog_attach(allow_prog, bar, BPF_CGROUP_INET_EGRESS,
+			    BPF_F_ALLOW_OVERRIDE)) {
+		log_err("Attaching prog to /foo/bar");
+		goto err;
+	}
+
+	if (bpf_prog_detach(foo, BPF_CGROUP_INET_EGRESS)) {
+		log_err("Detaching program from /foo");
+		goto err;
+	}
+
+	debug("Attached PASS from /foo/bar and detached DROP from /foo.\n"
+	       "This ping in cgroup /foo/bar should pass...\n");
+	assert(system(PING_CMD) == 0);
+
+	if (bpf_prog_attach(allow_prog, bar, BPF_CGROUP_INET_EGRESS,
+			    BPF_F_ALLOW_OVERRIDE)) {
+		log_err("Attaching prog to /foo/bar");
+		goto err;
+	}
+
+	if (!bpf_prog_attach(allow_prog, bar, BPF_CGROUP_INET_EGRESS, 0)) {
+		errno = 0;
+		log_err("Unexpected success attaching prog to /foo/bar");
+		goto err;
+	}
+
+	if (bpf_prog_detach(bar, BPF_CGROUP_INET_EGRESS)) {
+		log_err("Detaching program from /foo/bar");
+		goto err;
+	}
+
+	if (!bpf_prog_detach(foo, BPF_CGROUP_INET_EGRESS)) {
+		errno = 0;
+		log_err("Unexpected success in double detach from /foo");
+		goto err;
+	}
+
+	if (bpf_prog_attach(allow_prog, foo, BPF_CGROUP_INET_EGRESS, 0)) {
+		log_err("Attaching non-overridable prog to /foo");
+		goto err;
+	}
+
+	if (!bpf_prog_attach(allow_prog, bar, BPF_CGROUP_INET_EGRESS, 0)) {
+		errno = 0;
+		log_err("Unexpected success attaching non-overridable prog to /foo/bar");
+		goto err;
+	}
+
+	if (!bpf_prog_attach(allow_prog, bar, BPF_CGROUP_INET_EGRESS,
+			     BPF_F_ALLOW_OVERRIDE)) {
+		errno = 0;
+		log_err("Unexpected success attaching overridable prog to /foo/bar");
+		goto err;
+	}
+
+	if (!bpf_prog_attach(allow_prog, foo, BPF_CGROUP_INET_EGRESS,
+			     BPF_F_ALLOW_OVERRIDE)) {
+		errno = 0;
+		log_err("Unexpected success attaching overridable prog to /foo");
+		goto err;
+	}
+
+	if (bpf_prog_attach(drop_prog, foo, BPF_CGROUP_INET_EGRESS, 0)) {
+		log_err("Attaching different non-overridable prog to /foo");
+		goto err;
+	}
+
+	goto out;
+
+err:
+	rc = 1;
+
+out:
+	close(foo);
+	close(bar);
+	cleanup_cgroup_environment();
+	if (!rc)
+		printf("#override:PASS\n");
+	else
+		printf("#override:FAIL\n");
+	return rc;
+}
+
+static int map_fd = -1;
+
+static int prog_load_cnt(int verdict, int val)
+{
+	int cgroup_storage_fd, percpu_cgroup_storage_fd;
+
+	if (map_fd < 0)
+		map_fd = bpf_create_map(BPF_MAP_TYPE_ARRAY, 4, 8, 1, 0);
+	if (map_fd < 0) {
+		printf("failed to create map '%s'\n", strerror(errno));
+		return -1;
+	}
+
+	cgroup_storage_fd = bpf_create_map(BPF_MAP_TYPE_CGROUP_STORAGE,
+				sizeof(struct bpf_cgroup_storage_key), 8, 0, 0);
+	if (cgroup_storage_fd < 0) {
+		printf("failed to create map '%s'\n", strerror(errno));
+		return -1;
+	}
+
+	percpu_cgroup_storage_fd = bpf_create_map(
+		BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE,
+		sizeof(struct bpf_cgroup_storage_key), 8, 0, 0);
+	if (percpu_cgroup_storage_fd < 0) {
+		printf("failed to create map '%s'\n", strerror(errno));
+		return -1;
+	}
+
+	struct bpf_insn prog[] = {
+		BPF_MOV32_IMM(BPF_REG_0, 0),
+		BPF_STX_MEM(BPF_W, BPF_REG_10, BPF_REG_0, -4), /* *(u32 *)(fp - 4) = r0 */
+		BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
+		BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -4), /* r2 = fp - 4 */
+		BPF_LD_MAP_FD(BPF_REG_1, map_fd),
+		BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
+		BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 2),
+		BPF_MOV64_IMM(BPF_REG_1, val), /* r1 = 1 */
+		BPF_RAW_INSN(BPF_STX | BPF_XADD | BPF_DW, BPF_REG_0, BPF_REG_1, 0, 0), /* xadd r0 += r1 */
+
+		BPF_LD_MAP_FD(BPF_REG_1, cgroup_storage_fd),
+		BPF_MOV64_IMM(BPF_REG_2, 0),
+		BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_get_local_storage),
+		BPF_MOV64_IMM(BPF_REG_1, val),
+		BPF_RAW_INSN(BPF_STX | BPF_XADD | BPF_W, BPF_REG_0, BPF_REG_1, 0, 0),
+
+		BPF_LD_MAP_FD(BPF_REG_1, percpu_cgroup_storage_fd),
+		BPF_MOV64_IMM(BPF_REG_2, 0),
+		BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_get_local_storage),
+		BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_0, 0),
+		BPF_ALU64_IMM(BPF_ADD, BPF_REG_3, 0x1),
+		BPF_STX_MEM(BPF_W, BPF_REG_0, BPF_REG_3, 0),
+
+		BPF_MOV64_IMM(BPF_REG_0, verdict), /* r0 = verdict */
+		BPF_EXIT_INSN(),
+	};
+	size_t insns_cnt = sizeof(prog) / sizeof(struct bpf_insn);
+	int ret;
+
+	ret = bpf_load_program(BPF_PROG_TYPE_CGROUP_SKB,
+			       prog, insns_cnt, "GPL", 0,
+			       bpf_log_buf, BPF_LOG_BUF_SIZE);
+
+	if (ret < 0) {
+		log_err("Loading program");
+		printf("Output from verifier:\n%s\n-------\n", bpf_log_buf);
+		return 0;
+	}
+	close(cgroup_storage_fd);
+	return ret;
+}
+
+
+static int test_multiprog(void)
+{
+	__u32 prog_ids[4], prog_cnt = 0, attach_flags, saved_prog_id;
+	int cg1 = 0, cg2 = 0, cg3 = 0, cg4 = 0, cg5 = 0, key = 0;
+	int drop_prog, allow_prog[6] = {}, rc = 0;
+	unsigned long long value;
+	int i = 0;
+
+	for (i = 0; i < 6; i++) {
+		allow_prog[i] = prog_load_cnt(1, 1 << i);
+		if (!allow_prog[i])
+			goto err;
+	}
+	drop_prog = prog_load_cnt(0, 1);
+	if (!drop_prog)
+		goto err;
+
+	if (setup_cgroup_environment())
+		goto err;
+
+	cg1 = create_and_get_cgroup("/cg1");
+	if (cg1 < 0)
+		goto err;
+	cg2 = create_and_get_cgroup("/cg1/cg2");
+	if (cg2 < 0)
+		goto err;
+	cg3 = create_and_get_cgroup("/cg1/cg2/cg3");
+	if (cg3 < 0)
+		goto err;
+	cg4 = create_and_get_cgroup("/cg1/cg2/cg3/cg4");
+	if (cg4 < 0)
+		goto err;
+	cg5 = create_and_get_cgroup("/cg1/cg2/cg3/cg4/cg5");
+	if (cg5 < 0)
+		goto err;
+
+	if (join_cgroup("/cg1/cg2/cg3/cg4/cg5"))
+		goto err;
+
+	if (bpf_prog_attach(allow_prog[0], cg1, BPF_CGROUP_INET_EGRESS,
+			    BPF_F_ALLOW_MULTI)) {
+		log_err("Attaching prog to cg1");
+		goto err;
+	}
+	if (!bpf_prog_attach(allow_prog[0], cg1, BPF_CGROUP_INET_EGRESS,
+			     BPF_F_ALLOW_MULTI)) {
+		log_err("Unexpected success attaching the same prog to cg1");
+		goto err;
+	}
+	if (bpf_prog_attach(allow_prog[1], cg1, BPF_CGROUP_INET_EGRESS,
+			    BPF_F_ALLOW_MULTI)) {
+		log_err("Attaching prog2 to cg1");
+		goto err;
+	}
+	if (bpf_prog_attach(allow_prog[2], cg2, BPF_CGROUP_INET_EGRESS,
+			    BPF_F_ALLOW_OVERRIDE)) {
+		log_err("Attaching prog to cg2");
+		goto err;
+	}
+	if (bpf_prog_attach(allow_prog[3], cg3, BPF_CGROUP_INET_EGRESS,
+			    BPF_F_ALLOW_MULTI)) {
+		log_err("Attaching prog to cg3");
+		goto err;
+	}
+	if (bpf_prog_attach(allow_prog[4], cg4, BPF_CGROUP_INET_EGRESS,
+			    BPF_F_ALLOW_OVERRIDE)) {
+		log_err("Attaching prog to cg4");
+		goto err;
+	}
+	if (bpf_prog_attach(allow_prog[5], cg5, BPF_CGROUP_INET_EGRESS, 0)) {
+		log_err("Attaching prog to cg5");
+		goto err;
+	}
+	assert(system(PING_CMD) == 0);
+	assert(bpf_map_lookup_elem(map_fd, &key, &value) == 0);
+	assert(value == 1 + 2 + 8 + 32);
+
+	/* query the number of effective progs in cg5 */
+	assert(bpf_prog_query(cg5, BPF_CGROUP_INET_EGRESS, BPF_F_QUERY_EFFECTIVE,
+			      NULL, NULL, &prog_cnt) == 0);
+	assert(prog_cnt == 4);
+	/* retrieve prog_ids of effective progs in cg5 */
+	assert(bpf_prog_query(cg5, BPF_CGROUP_INET_EGRESS, BPF_F_QUERY_EFFECTIVE,
+			      &attach_flags, prog_ids, &prog_cnt) == 0);
+	assert(prog_cnt == 4);
+	assert(attach_flags == 0);
+	saved_prog_id = prog_ids[0];
+	/* check enospc handling */
+	prog_ids[0] = 0;
+	prog_cnt = 2;
+	assert(bpf_prog_query(cg5, BPF_CGROUP_INET_EGRESS, BPF_F_QUERY_EFFECTIVE,
+			      &attach_flags, prog_ids, &prog_cnt) == -1 &&
+	       errno == ENOSPC);
+	assert(prog_cnt == 4);
+	/* check that prog_ids are returned even when buffer is too small */
+	assert(prog_ids[0] == saved_prog_id);
+	/* retrieve prog_id of single attached prog in cg5 */
+	prog_ids[0] = 0;
+	assert(bpf_prog_query(cg5, BPF_CGROUP_INET_EGRESS, 0,
+			      NULL, prog_ids, &prog_cnt) == 0);
+	assert(prog_cnt == 1);
+	assert(prog_ids[0] == saved_prog_id);
+
+	/* detach bottom program and ping again */
+	if (bpf_prog_detach2(-1, cg5, BPF_CGROUP_INET_EGRESS)) {
+		log_err("Detaching prog from cg5");
+		goto err;
+	}
+	value = 0;
+	assert(bpf_map_update_elem(map_fd, &key, &value, 0) == 0);
+	assert(system(PING_CMD) == 0);
+	assert(bpf_map_lookup_elem(map_fd, &key, &value) == 0);
+	assert(value == 1 + 2 + 8 + 16);
+
+	/* detach 3rd from bottom program and ping again */
+	errno = 0;
+	if (!bpf_prog_detach2(0, cg3, BPF_CGROUP_INET_EGRESS)) {
+		log_err("Unexpected success on detach from cg3");
+		goto err;
+	}
+	if (bpf_prog_detach2(allow_prog[3], cg3, BPF_CGROUP_INET_EGRESS)) {
+		log_err("Detaching from cg3");
+		goto err;
+	}
+	value = 0;
+	assert(bpf_map_update_elem(map_fd, &key, &value, 0) == 0);
+	assert(system(PING_CMD) == 0);
+	assert(bpf_map_lookup_elem(map_fd, &key, &value) == 0);
+	assert(value == 1 + 2 + 16);
+
+	/* detach 2nd from bottom program and ping again */
+	if (bpf_prog_detach2(-1, cg4, BPF_CGROUP_INET_EGRESS)) {
+		log_err("Detaching prog from cg4");
+		goto err;
+	}
+	value = 0;
+	assert(bpf_map_update_elem(map_fd, &key, &value, 0) == 0);
+	assert(system(PING_CMD) == 0);
+	assert(bpf_map_lookup_elem(map_fd, &key, &value) == 0);
+	assert(value == 1 + 2 + 4);
+
+	prog_cnt = 4;
+	assert(bpf_prog_query(cg5, BPF_CGROUP_INET_EGRESS, BPF_F_QUERY_EFFECTIVE,
+			      &attach_flags, prog_ids, &prog_cnt) == 0);
+	assert(prog_cnt == 3);
+	assert(attach_flags == 0);
+	assert(bpf_prog_query(cg5, BPF_CGROUP_INET_EGRESS, 0,
+			      NULL, prog_ids, &prog_cnt) == 0);
+	assert(prog_cnt == 0);
+	goto out;
+err:
+	rc = 1;
+
+out:
+	for (i = 0; i < 6; i++)
+		if (allow_prog[i] > 0)
+			close(allow_prog[i]);
+	close(cg1);
+	close(cg2);
+	close(cg3);
+	close(cg4);
+	close(cg5);
+	cleanup_cgroup_environment();
+	if (!rc)
+		printf("#multi:PASS\n");
+	else
+		printf("#multi:FAIL\n");
+	return rc;
+}
+
+static int test_autodetach(void)
+{
+	__u32 prog_cnt = 4, attach_flags;
+	int allow_prog[2] = {0};
+	__u32 prog_ids[2] = {0};
+	int cg = 0, i, rc = -1;
+	void *ptr = NULL;
+	int attempts;
+
+	for (i = 0; i < ARRAY_SIZE(allow_prog); i++) {
+		allow_prog[i] = prog_load_cnt(1, 1 << i);
+		if (!allow_prog[i])
+			goto err;
+	}
+
+	if (setup_cgroup_environment())
+		goto err;
+
+	/* create a cgroup, attach two programs and remember their ids */
+	cg = create_and_get_cgroup("/cg_autodetach");
+	if (cg < 0)
+		goto err;
+
+	if (join_cgroup("/cg_autodetach"))
+		goto err;
+
+	for (i = 0; i < ARRAY_SIZE(allow_prog); i++) {
+		if (bpf_prog_attach(allow_prog[i], cg, BPF_CGROUP_INET_EGRESS,
+				    BPF_F_ALLOW_MULTI)) {
+			log_err("Attaching prog[%d] to cg:egress", i);
+			goto err;
+		}
+	}
+
+	/* make sure that programs are attached and run some traffic */
+	assert(bpf_prog_query(cg, BPF_CGROUP_INET_EGRESS, 0, &attach_flags,
+			      prog_ids, &prog_cnt) == 0);
+	assert(system(PING_CMD) == 0);
+
+	/* allocate some memory (4Mb) to pin the original cgroup */
+	ptr = malloc(4 * (1 << 20));
+	if (!ptr)
+		goto err;
+
+	/* close programs and cgroup fd */
+	for (i = 0; i < ARRAY_SIZE(allow_prog); i++) {
+		close(allow_prog[i]);
+		allow_prog[i] = 0;
+	}
+
+	close(cg);
+	cg = 0;
+
+	/* leave the cgroup and remove it. don't detach programs */
+	cleanup_cgroup_environment();
+
+	/* wait for the asynchronous auto-detachment.
+	 * wait for no more than 5 sec and give up.
+	 */
+	for (i = 0; i < ARRAY_SIZE(prog_ids); i++) {
+		for (attempts = 5; attempts >= 0; attempts--) {
+			int fd = bpf_prog_get_fd_by_id(prog_ids[i]);
+
+			if (fd < 0)
+				break;
+
+			/* don't leave the fd open */
+			close(fd);
+
+			if (!attempts)
+				goto err;
+
+			sleep(1);
+		}
+	}
+
+	rc = 0;
+err:
+	for (i = 0; i < ARRAY_SIZE(allow_prog); i++)
+		if (allow_prog[i] > 0)
+			close(allow_prog[i]);
+	if (cg)
+		close(cg);
+	free(ptr);
+	cleanup_cgroup_environment();
+	if (!rc)
+		printf("#autodetach:PASS\n");
+	else
+		printf("#autodetach:FAIL\n");
+	return rc;
+}
+
+int main(void)
+{
+	int (*tests[])(void) = {
+		test_foo_bar,
+		test_multiprog,
+		test_autodetach,
+	};
+	int errors = 0;
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(tests); i++)
+		if (tests[i]())
+			errors++;
+
+	if (errors)
+		printf("test_cgroup_attach:FAIL\n");
+	else
+		printf("test_cgroup_attach:PASS\n");
+
+	return errors ? EXIT_FAILURE : EXIT_SUCCESS;
+}
diff --git a/tools/testing/selftests/bpf/test_hashmap.c b/tools/testing/selftests/bpf/test_hashmap.c
new file mode 100644
index 000000000000..b64094c981e3
--- /dev/null
+++ b/tools/testing/selftests/bpf/test_hashmap.c
@@ -0,0 +1,382 @@
+// SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
+
+/*
+ * Tests for libbpf's hashmap.
+ *
+ * Copyright (c) 2019 Facebook
+ */
+#include <stdio.h>
+#include <errno.h>
+#include <linux/err.h>
+#include "hashmap.h"
+
+#define CHECK(condition, format...) ({					\
+	int __ret = !!(condition);					\
+	if (__ret) {							\
+		fprintf(stderr, "%s:%d:FAIL ", __func__, __LINE__);	\
+		fprintf(stderr, format);				\
+	}								\
+	__ret;								\
+})
+
+size_t hash_fn(const void *k, void *ctx)
+{
+	return (long)k;
+}
+
+bool equal_fn(const void *a, const void *b, void *ctx)
+{
+	return (long)a == (long)b;
+}
+
+static inline size_t next_pow_2(size_t n)
+{
+	size_t r = 1;
+
+	while (r < n)
+		r <<= 1;
+	return r;
+}
+
+static inline size_t exp_cap(size_t sz)
+{
+	size_t r = next_pow_2(sz);
+
+	if (sz * 4 / 3 > r)
+		r <<= 1;
+	return r;
+}
+
+#define ELEM_CNT 62
+
+int test_hashmap_generic(void)
+{
+	struct hashmap_entry *entry, *tmp;
+	int err, bkt, found_cnt, i;
+	long long found_msk;
+	struct hashmap *map;
+
+	fprintf(stderr, "%s: ", __func__);
+
+	map = hashmap__new(hash_fn, equal_fn, NULL);
+	if (CHECK(IS_ERR(map), "failed to create map: %ld\n", PTR_ERR(map)))
+		return 1;
+
+	for (i = 0; i < ELEM_CNT; i++) {
+		const void *oldk, *k = (const void *)(long)i;
+		void *oldv, *v = (void *)(long)(1024 + i);
+
+		err = hashmap__update(map, k, v, &oldk, &oldv);
+		if (CHECK(err != -ENOENT, "unexpected result: %d\n", err))
+			return 1;
+
+		if (i % 2) {
+			err = hashmap__add(map, k, v);
+		} else {
+			err = hashmap__set(map, k, v, &oldk, &oldv);
+			if (CHECK(oldk != NULL || oldv != NULL,
+				  "unexpected k/v: %p=%p\n", oldk, oldv))
+				return 1;
+		}
+
+		if (CHECK(err, "failed to add k/v %ld = %ld: %d\n",
+			       (long)k, (long)v, err))
+			return 1;
+
+		if (CHECK(!hashmap__find(map, k, &oldv),
+			  "failed to find key %ld\n", (long)k))
+			return 1;
+		if (CHECK(oldv != v, "found value is wrong: %ld\n", (long)oldv))
+			return 1;
+	}
+
+	if (CHECK(hashmap__size(map) != ELEM_CNT,
+		  "invalid map size: %zu\n", hashmap__size(map)))
+		return 1;
+	if (CHECK(hashmap__capacity(map) != exp_cap(hashmap__size(map)),
+		  "unexpected map capacity: %zu\n", hashmap__capacity(map)))
+		return 1;
+
+	found_msk = 0;
+	hashmap__for_each_entry(map, entry, bkt) {
+		long k = (long)entry->key;
+		long v = (long)entry->value;
+
+		found_msk |= 1ULL << k;
+		if (CHECK(v - k != 1024, "invalid k/v pair: %ld = %ld\n", k, v))
+			return 1;
+	}
+	if (CHECK(found_msk != (1ULL << ELEM_CNT) - 1,
+		  "not all keys iterated: %llx\n", found_msk))
+		return 1;
+
+	for (i = 0; i < ELEM_CNT; i++) {
+		const void *oldk, *k = (const void *)(long)i;
+		void *oldv, *v = (void *)(long)(256 + i);
+
+		err = hashmap__add(map, k, v);
+		if (CHECK(err != -EEXIST, "unexpected add result: %d\n", err))
+			return 1;
+
+		if (i % 2)
+			err = hashmap__update(map, k, v, &oldk, &oldv);
+		else
+			err = hashmap__set(map, k, v, &oldk, &oldv);
+
+		if (CHECK(err, "failed to update k/v %ld = %ld: %d\n",
+			       (long)k, (long)v, err))
+			return 1;
+		if (CHECK(!hashmap__find(map, k, &oldv),
+			  "failed to find key %ld\n", (long)k))
+			return 1;
+		if (CHECK(oldv != v, "found value is wrong: %ld\n", (long)oldv))
+			return 1;
+	}
+
+	if (CHECK(hashmap__size(map) != ELEM_CNT,
+		  "invalid updated map size: %zu\n", hashmap__size(map)))
+		return 1;
+	if (CHECK(hashmap__capacity(map) != exp_cap(hashmap__size(map)),
+		  "unexpected map capacity: %zu\n", hashmap__capacity(map)))
+		return 1;
+
+	found_msk = 0;
+	hashmap__for_each_entry_safe(map, entry, tmp, bkt) {
+		long k = (long)entry->key;
+		long v = (long)entry->value;
+
+		found_msk |= 1ULL << k;
+		if (CHECK(v - k != 256,
+			  "invalid updated k/v pair: %ld = %ld\n", k, v))
+			return 1;
+	}
+	if (CHECK(found_msk != (1ULL << ELEM_CNT) - 1,
+		  "not all keys iterated after update: %llx\n", found_msk))
+		return 1;
+
+	found_cnt = 0;
+	hashmap__for_each_key_entry(map, entry, (void *)0) {
+		found_cnt++;
+	}
+	if (CHECK(!found_cnt, "didn't find any entries for key 0\n"))
+		return 1;
+
+	found_msk = 0;
+	found_cnt = 0;
+	hashmap__for_each_key_entry_safe(map, entry, tmp, (void *)0) {
+		const void *oldk, *k;
+		void *oldv, *v;
+
+		k = entry->key;
+		v = entry->value;
+
+		found_cnt++;
+		found_msk |= 1ULL << (long)k;
+
+		if (CHECK(!hashmap__delete(map, k, &oldk, &oldv),
+			  "failed to delete k/v %ld = %ld\n",
+			  (long)k, (long)v))
+			return 1;
+		if (CHECK(oldk != k || oldv != v,
+			  "invalid deleted k/v: expected %ld = %ld, got %ld = %ld\n",
+			  (long)k, (long)v, (long)oldk, (long)oldv))
+			return 1;
+		if (CHECK(hashmap__delete(map, k, &oldk, &oldv),
+			  "unexpectedly deleted k/v %ld = %ld\n",
+			  (long)oldk, (long)oldv))
+			return 1;
+	}
+
+	if (CHECK(!found_cnt || !found_msk,
+		  "didn't delete any key entries\n"))
+		return 1;
+	if (CHECK(hashmap__size(map) != ELEM_CNT - found_cnt,
+		  "invalid updated map size (already deleted: %d): %zu\n",
+		  found_cnt, hashmap__size(map)))
+		return 1;
+	if (CHECK(hashmap__capacity(map) != exp_cap(hashmap__size(map)),
+		  "unexpected map capacity: %zu\n", hashmap__capacity(map)))
+		return 1;
+
+	hashmap__for_each_entry_safe(map, entry, tmp, bkt) {
+		const void *oldk, *k;
+		void *oldv, *v;
+
+		k = entry->key;
+		v = entry->value;
+
+		found_cnt++;
+		found_msk |= 1ULL << (long)k;
+
+		if (CHECK(!hashmap__delete(map, k, &oldk, &oldv),
+			  "failed to delete k/v %ld = %ld\n",
+			  (long)k, (long)v))
+			return 1;
+		if (CHECK(oldk != k || oldv != v,
+			  "invalid old k/v: expect %ld = %ld, got %ld = %ld\n",
+			  (long)k, (long)v, (long)oldk, (long)oldv))
+			return 1;
+		if (CHECK(hashmap__delete(map, k, &oldk, &oldv),
+			  "unexpectedly deleted k/v %ld = %ld\n",
+			  (long)k, (long)v))
+			return 1;
+	}
+
+	if (CHECK(found_cnt != ELEM_CNT || found_msk != (1ULL << ELEM_CNT) - 1,
+		  "not all keys were deleted: found_cnt:%d, found_msk:%llx\n",
+		  found_cnt, found_msk))
+		return 1;
+	if (CHECK(hashmap__size(map) != 0,
+		  "invalid updated map size (already deleted: %d): %zu\n",
+		  found_cnt, hashmap__size(map)))
+		return 1;
+
+	found_cnt = 0;
+	hashmap__for_each_entry(map, entry, bkt) {
+		CHECK(false, "unexpected map entries left: %ld = %ld\n",
+			     (long)entry->key, (long)entry->value);
+		return 1;
+	}
+
+	hashmap__free(map);
+	hashmap__for_each_entry(map, entry, bkt) {
+		CHECK(false, "unexpected map entries left: %ld = %ld\n",
+			     (long)entry->key, (long)entry->value);
+		return 1;
+	}
+
+	fprintf(stderr, "OK\n");
+	return 0;
+}
+
+size_t collision_hash_fn(const void *k, void *ctx)
+{
+	return 0;
+}
+
+int test_hashmap_multimap(void)
+{
+	void *k1 = (void *)0, *k2 = (void *)1;
+	struct hashmap_entry *entry;
+	struct hashmap *map;
+	long found_msk;
+	int err, bkt;
+
+	fprintf(stderr, "%s: ", __func__);
+
+	/* force collisions */
+	map = hashmap__new(collision_hash_fn, equal_fn, NULL);
+	if (CHECK(IS_ERR(map), "failed to create map: %ld\n", PTR_ERR(map)))
+		return 1;
+
+
+	/* set up multimap:
+	 * [0] -> 1, 2, 4;
+	 * [1] -> 8, 16, 32;
+	 */
+	err = hashmap__append(map, k1, (void *)1);
+	if (CHECK(err, "failed to add k/v: %d\n", err))
+		return 1;
+	err = hashmap__append(map, k1, (void *)2);
+	if (CHECK(err, "failed to add k/v: %d\n", err))
+		return 1;
+	err = hashmap__append(map, k1, (void *)4);
+	if (CHECK(err, "failed to add k/v: %d\n", err))
+		return 1;
+
+	err = hashmap__append(map, k2, (void *)8);
+	if (CHECK(err, "failed to add k/v: %d\n", err))
+		return 1;
+	err = hashmap__append(map, k2, (void *)16);
+	if (CHECK(err, "failed to add k/v: %d\n", err))
+		return 1;
+	err = hashmap__append(map, k2, (void *)32);
+	if (CHECK(err, "failed to add k/v: %d\n", err))
+		return 1;
+
+	if (CHECK(hashmap__size(map) != 6,
+		  "invalid map size: %zu\n", hashmap__size(map)))
+		return 1;
+
+	/* verify global iteration still works and sees all values */
+	found_msk = 0;
+	hashmap__for_each_entry(map, entry, bkt) {
+		found_msk |= (long)entry->value;
+	}
+	if (CHECK(found_msk != (1 << 6) - 1,
+		  "not all keys iterated: %lx\n", found_msk))
+		return 1;
+
+	/* iterate values for key 1 */
+	found_msk = 0;
+	hashmap__for_each_key_entry(map, entry, k1) {
+		found_msk |= (long)entry->value;
+	}
+	if (CHECK(found_msk != (1 | 2 | 4),
+		  "invalid k1 values: %lx\n", found_msk))
+		return 1;
+
+	/* iterate values for key 2 */
+	found_msk = 0;
+	hashmap__for_each_key_entry(map, entry, k2) {
+		found_msk |= (long)entry->value;
+	}
+	if (CHECK(found_msk != (8 | 16 | 32),
+		  "invalid k2 values: %lx\n", found_msk))
+		return 1;
+
+	fprintf(stderr, "OK\n");
+	return 0;
+}
+
+int test_hashmap_empty()
+{
+	struct hashmap_entry *entry;
+	int bkt;
+	struct hashmap *map;
+	void *k = (void *)0;
+
+	fprintf(stderr, "%s: ", __func__);
+
+	/* force collisions */
+	map = hashmap__new(hash_fn, equal_fn, NULL);
+	if (CHECK(IS_ERR(map), "failed to create map: %ld\n", PTR_ERR(map)))
+		return 1;
+
+	if (CHECK(hashmap__size(map) != 0,
+		  "invalid map size: %zu\n", hashmap__size(map)))
+		return 1;
+	if (CHECK(hashmap__capacity(map) != 0,
+		  "invalid map capacity: %zu\n", hashmap__capacity(map)))
+		return 1;
+	if (CHECK(hashmap__find(map, k, NULL), "unexpected find\n"))
+		return 1;
+	if (CHECK(hashmap__delete(map, k, NULL, NULL), "unexpected delete\n"))
+		return 1;
+
+	hashmap__for_each_entry(map, entry, bkt) {
+		CHECK(false, "unexpected iterated entry\n");
+		return 1;
+	}
+	hashmap__for_each_key_entry(map, entry, k) {
+		CHECK(false, "unexpected key entry\n");
+		return 1;
+	}
+
+	fprintf(stderr, "OK\n");
+	return 0;
+}
+
+int main(int argc, char **argv)
+{
+	bool failed = false;
+
+	if (test_hashmap_generic())
+		failed = true;
+	if (test_hashmap_multimap())
+		failed = true;
+	if (test_hashmap_empty())
+		failed = true;
+
+	return failed;
+}
diff --git a/tools/testing/selftests/bpf/test_sock_addr.c b/tools/testing/selftests/bpf/test_sock_addr.c
index 3f110eaaf29c..5d0c4f0baeff 100644
--- a/tools/testing/selftests/bpf/test_sock_addr.c
+++ b/tools/testing/selftests/bpf/test_sock_addr.c
@@ -745,6 +745,7 @@ static int load_path(const struct sock_addr_test *test, const char *path)
 	attr.file = path;
 	attr.prog_type = BPF_PROG_TYPE_CGROUP_SOCK_ADDR;
 	attr.expected_attach_type = test->expected_attach_type;
+	attr.prog_flags = BPF_F_TEST_RND_HI32;
 
 	if (bpf_prog_load_xattr(&attr, &obj, &prog_fd)) {
 		if (test->expected_result != LOAD_REJECT)
diff --git a/tools/testing/selftests/bpf/test_sock_fields.c b/tools/testing/selftests/bpf/test_sock_fields.c
index e089477fa0a3..f0fc103261a4 100644
--- a/tools/testing/selftests/bpf/test_sock_fields.c
+++ b/tools/testing/selftests/bpf/test_sock_fields.c
@@ -414,6 +414,7 @@ int main(int argc, char **argv)
 	struct bpf_prog_load_attr attr = {
 		.file = "test_sock_fields_kern.o",
 		.prog_type = BPF_PROG_TYPE_CGROUP_SKB,
+		.prog_flags = BPF_F_TEST_RND_HI32,
 	};
 	int cgroup_fd, egress_fd, ingress_fd, err;
 	struct bpf_program *ingress_prog;
diff --git a/tools/testing/selftests/bpf/test_socket_cookie.c b/tools/testing/selftests/bpf/test_socket_cookie.c
index e51d63786ff8..cac8ee57a013 100644
--- a/tools/testing/selftests/bpf/test_socket_cookie.c
+++ b/tools/testing/selftests/bpf/test_socket_cookie.c
@@ -148,6 +148,7 @@ static int run_test(int cgfd)
 	memset(&attr, 0, sizeof(attr));
 	attr.file = SOCKET_COOKIE_PROG;
 	attr.prog_type = BPF_PROG_TYPE_UNSPEC;
+	attr.prog_flags = BPF_F_TEST_RND_HI32;
 
 	err = bpf_prog_load_xattr(&attr, &pobj, &prog_fd);
 	if (err) {
diff --git a/tools/testing/selftests/bpf/test_sockmap_kern.h b/tools/testing/selftests/bpf/test_sockmap_kern.h
index e7639f66a941..4e7d3da21357 100644
--- a/tools/testing/selftests/bpf/test_sockmap_kern.h
+++ b/tools/testing/selftests/bpf/test_sockmap_kern.h
@@ -28,13 +28,6 @@
  * are established and verdicts are decided.
  */
 
-#define bpf_printk(fmt, ...)					\
-({								\
-	       char ____fmt[] = fmt;				\
-	       bpf_trace_printk(____fmt, sizeof(____fmt),	\
-				##__VA_ARGS__);			\
-})
-
 struct bpf_map_def SEC("maps") sock_map = {
 	.type = TEST_MAP_TYPE,
 	.key_size = sizeof(int),
diff --git a/tools/testing/selftests/bpf/test_stub.c b/tools/testing/selftests/bpf/test_stub.c
new file mode 100644
index 000000000000..84e81a89e2f9
--- /dev/null
+++ b/tools/testing/selftests/bpf/test_stub.c
@@ -0,0 +1,40 @@
+// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+/* Copyright (C) 2019 Netronome Systems, Inc. */
+
+#include <bpf/bpf.h>
+#include <bpf/libbpf.h>
+#include <string.h>
+
+int bpf_prog_test_load(const char *file, enum bpf_prog_type type,
+		       struct bpf_object **pobj, int *prog_fd)
+{
+	struct bpf_prog_load_attr attr;
+
+	memset(&attr, 0, sizeof(struct bpf_prog_load_attr));
+	attr.file = file;
+	attr.prog_type = type;
+	attr.expected_attach_type = 0;
+	attr.prog_flags = BPF_F_TEST_RND_HI32;
+
+	return bpf_prog_load_xattr(&attr, pobj, prog_fd);
+}
+
+int bpf_test_load_program(enum bpf_prog_type type, const struct bpf_insn *insns,
+			  size_t insns_cnt, const char *license,
+			  __u32 kern_version, char *log_buf,
+		     size_t log_buf_sz)
+{
+	struct bpf_load_program_attr load_attr;
+
+	memset(&load_attr, 0, sizeof(struct bpf_load_program_attr));
+	load_attr.prog_type = type;
+	load_attr.expected_attach_type = 0;
+	load_attr.name = NULL;
+	load_attr.insns = insns;
+	load_attr.insns_cnt = insns_cnt;
+	load_attr.license = license;
+	load_attr.kern_version = kern_version;
+	load_attr.prog_flags = BPF_F_TEST_RND_HI32;
+
+	return bpf_load_program_xattr(&load_attr, log_buf, log_buf_sz);
+}
diff --git a/tools/testing/selftests/bpf/test_tunnel.sh b/tools/testing/selftests/bpf/test_tunnel.sh
index 546aee3e9fb4..bd12ec97a44d 100755
--- a/tools/testing/selftests/bpf/test_tunnel.sh
+++ b/tools/testing/selftests/bpf/test_tunnel.sh
@@ -696,30 +696,57 @@ check_err()
 
 bpf_tunnel_test()
 {
+	local errors=0
+
 	echo "Testing GRE tunnel..."
 	test_gre
+	errors=$(( $errors + $? ))
+
 	echo "Testing IP6GRE tunnel..."
 	test_ip6gre
+	errors=$(( $errors + $? ))
+
 	echo "Testing IP6GRETAP tunnel..."
 	test_ip6gretap
+	errors=$(( $errors + $? ))
+
 	echo "Testing ERSPAN tunnel..."
 	test_erspan v2
+	errors=$(( $errors + $? ))
+
 	echo "Testing IP6ERSPAN tunnel..."
 	test_ip6erspan v2
+	errors=$(( $errors + $? ))
+
 	echo "Testing VXLAN tunnel..."
 	test_vxlan
+	errors=$(( $errors + $? ))
+
 	echo "Testing IP6VXLAN tunnel..."
 	test_ip6vxlan
+	errors=$(( $errors + $? ))
+
 	echo "Testing GENEVE tunnel..."
 	test_geneve
+	errors=$(( $errors + $? ))
+
 	echo "Testing IP6GENEVE tunnel..."
 	test_ip6geneve
+	errors=$(( $errors + $? ))
+
 	echo "Testing IPIP tunnel..."
 	test_ipip
+	errors=$(( $errors + $? ))
+
 	echo "Testing IPIP6 tunnel..."
 	test_ipip6
+	errors=$(( $errors + $? ))
+
 	echo "Testing IPSec tunnel..."
 	test_xfrm_tunnel
+	errors=$(( $errors + $? ))
+
+	return $errors
 }
 
 trap cleanup 0 3 6
@@ -728,4 +755,9 @@ trap cleanup_exit 2 9
 cleanup
 bpf_tunnel_test
 
+if [ $? -ne 0 ]; then
+	echo -e "$(basename $0): ${RED}FAIL${NC}"
+	exit 1
+fi
+echo -e "$(basename $0): ${GREEN}PASS${NC}"
 exit 0
diff --git a/tools/testing/selftests/bpf/test_verifier.c b/tools/testing/selftests/bpf/test_verifier.c
index ccd896b98cac..cd0248c54e25 100644
--- a/tools/testing/selftests/bpf/test_verifier.c
+++ b/tools/testing/selftests/bpf/test_verifier.c
@@ -138,32 +138,36 @@ static void bpf_fill_ld_abs_vlan_push_pop(struct bpf_test *self)
 loop:
 	for (j = 0; j < PUSH_CNT; j++) {
 		insn[i++] = BPF_LD_ABS(BPF_B, 0);
-		insn[i] = BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0x34, len - i - 2);
+		/* jump to error label */
+		insn[i] = BPF_JMP32_IMM(BPF_JNE, BPF_REG_0, 0x34, len - i - 3);
 		i++;
 		insn[i++] = BPF_MOV64_REG(BPF_REG_1, BPF_REG_6);
 		insn[i++] = BPF_MOV64_IMM(BPF_REG_2, 1);
 		insn[i++] = BPF_MOV64_IMM(BPF_REG_3, 2);
 		insn[i++] = BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
 					 BPF_FUNC_skb_vlan_push),
-		insn[i] = BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, len - i - 2);
+		insn[i] = BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, len - i - 3);
 		i++;
 	}
 
 	for (j = 0; j < PUSH_CNT; j++) {
 		insn[i++] = BPF_LD_ABS(BPF_B, 0);
-		insn[i] = BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0x34, len - i - 2);
+		insn[i] = BPF_JMP32_IMM(BPF_JNE, BPF_REG_0, 0x34, len - i - 3);
 		i++;
 		insn[i++] = BPF_MOV64_REG(BPF_REG_1, BPF_REG_6);
 		insn[i++] = BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
 					 BPF_FUNC_skb_vlan_pop),
-		insn[i] = BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, len - i - 2);
+		insn[i] = BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, len - i - 3);
 		i++;
 	}
 	if (++k < 5)
 		goto loop;
 
-	for (; i < len - 1; i++)
-		insn[i] = BPF_ALU32_IMM(BPF_MOV, BPF_REG_0, 0xbef);
+	for (; i < len - 3; i++)
+		insn[i] = BPF_ALU64_IMM(BPF_MOV, BPF_REG_0, 0xbef);
+	insn[len - 3] = BPF_JMP_A(1);
+	/* error label */
+	insn[len - 2] = BPF_MOV32_IMM(BPF_REG_0, 0);
 	insn[len - 1] = BPF_EXIT_INSN();
 	self->prog_len = len;
 }
@@ -171,8 +175,13 @@ loop:
 static void bpf_fill_jump_around_ld_abs(struct bpf_test *self)
 {
 	struct bpf_insn *insn = self->fill_insns;
-	/* jump range is limited to 16 bit. every ld_abs is replaced by 6 insns */
-	unsigned int len = (1 << 15) / 6;
+	/* jump range is limited to 16 bit. every ld_abs is replaced by 6 insns,
+	 * but on arches like arm, ppc etc, there will be one BPF_ZEXT inserted
+	 * to extend the error value of the inlined ld_abs sequence which then
+	 * contains 7 insns. so, set the dividend to 7 so the testcase could
+	 * work on all arches.
+	 */
+	unsigned int len = (1 << 15) / 7;
 	int i = 0;
 
 	insn[i++] = BPF_MOV64_REG(BPF_REG_6, BPF_REG_1);
@@ -210,33 +219,35 @@ static void bpf_fill_rand_ld_dw(struct bpf_test *self)
 	self->retval = (uint32_t)res;
 }
 
-/* test the sequence of 1k jumps */
+#define MAX_JMP_SEQ 8192
+
+/* test the sequence of 8k jumps */
 static void bpf_fill_scale1(struct bpf_test *self)
 {
 	struct bpf_insn *insn = self->fill_insns;
 	int i = 0, k = 0;
 
 	insn[i++] = BPF_MOV64_REG(BPF_REG_6, BPF_REG_1);
-	/* test to check that the sequence of 1024 jumps is acceptable */
-	while (k++ < 1024) {
+	/* test to check that the long sequence of jumps is acceptable */
+	while (k++ < MAX_JMP_SEQ) {
 		insn[i++] = BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
 					 BPF_FUNC_get_prandom_u32);
-		insn[i++] = BPF_JMP_IMM(BPF_JGT, BPF_REG_0, bpf_semi_rand_get(), 2);
+		insn[i++] = BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, bpf_semi_rand_get(), 2);
 		insn[i++] = BPF_MOV64_REG(BPF_REG_1, BPF_REG_10);
 		insn[i++] = BPF_STX_MEM(BPF_DW, BPF_REG_1, BPF_REG_6,
 					-8 * (k % 64 + 1));
 	}
-	/* every jump adds 1024 steps to insn_processed, so to stay exactly
-	 * within 1m limit add MAX_TEST_INSNS - 1025 MOVs and 1 EXIT
+	/* every jump adds 1 step to insn_processed, so to stay exactly
+	 * within 1m limit add MAX_TEST_INSNS - MAX_JMP_SEQ - 1 MOVs and 1 EXIT
 	 */
-	while (i < MAX_TEST_INSNS - 1025)
-		insn[i++] = BPF_ALU32_IMM(BPF_MOV, BPF_REG_0, 42);
+	while (i < MAX_TEST_INSNS - MAX_JMP_SEQ - 1)
+		insn[i++] = BPF_ALU64_IMM(BPF_MOV, BPF_REG_0, 42);
 	insn[i] = BPF_EXIT_INSN();
 	self->prog_len = i + 1;
 	self->retval = 42;
 }
 
-/* test the sequence of 1k jumps in inner most function (function depth 8)*/
+/* test the sequence of 8k jumps in inner most function (function depth 8)*/
 static void bpf_fill_scale2(struct bpf_test *self)
 {
 	struct bpf_insn *insn = self->fill_insns;
@@ -248,20 +259,21 @@ static void bpf_fill_scale2(struct bpf_test *self)
 		insn[i++] = BPF_EXIT_INSN();
 	}
 	insn[i++] = BPF_MOV64_REG(BPF_REG_6, BPF_REG_1);
-	/* test to check that the sequence of 1024 jumps is acceptable */
-	while (k++ < 1024) {
+	/* test to check that the long sequence of jumps is acceptable */
+	k = 0;
+	while (k++ < MAX_JMP_SEQ) {
 		insn[i++] = BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
 					 BPF_FUNC_get_prandom_u32);
-		insn[i++] = BPF_JMP_IMM(BPF_JGT, BPF_REG_0, bpf_semi_rand_get(), 2);
+		insn[i++] = BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, bpf_semi_rand_get(), 2);
 		insn[i++] = BPF_MOV64_REG(BPF_REG_1, BPF_REG_10);
 		insn[i++] = BPF_STX_MEM(BPF_DW, BPF_REG_1, BPF_REG_6,
 					-8 * (k % (64 - 4 * FUNC_NEST) + 1));
 	}
-	/* every jump adds 1024 steps to insn_processed, so to stay exactly
-	 * within 1m limit add MAX_TEST_INSNS - 1025 MOVs and 1 EXIT
+	/* every jump adds 1 step to insn_processed, so to stay exactly
+	 * within 1m limit add MAX_TEST_INSNS - MAX_JMP_SEQ - 1 MOVs and 1 EXIT
 	 */
-	while (i < MAX_TEST_INSNS - 1025)
-		insn[i++] = BPF_ALU32_IMM(BPF_MOV, BPF_REG_0, 42);
+	while (i < MAX_TEST_INSNS - MAX_JMP_SEQ - 1)
+		insn[i++] = BPF_ALU64_IMM(BPF_MOV, BPF_REG_0, 42);
 	insn[i] = BPF_EXIT_INSN();
 	self->prog_len = i + 1;
 	self->retval = 42;
@@ -870,7 +882,7 @@ static void do_test_single(struct bpf_test *test, bool unpriv,
 	if (fixup_skips != skips)
 		return;
 
-	pflags = 0;
+	pflags = BPF_F_TEST_RND_HI32;
 	if (test->flags & F_LOAD_WITH_STRICT_ALIGNMENT)
 		pflags |= BPF_F_STRICT_ALIGNMENT;
 	if (test->flags & F_NEEDS_EFFICIENT_UNALIGNED_ACCESS)
diff --git a/tools/testing/selftests/bpf/test_xdping.sh b/tools/testing/selftests/bpf/test_xdping.sh
new file mode 100755
index 000000000000..c2f0ddb45531
--- /dev/null
+++ b/tools/testing/selftests/bpf/test_xdping.sh
@@ -0,0 +1,99 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+
+# xdping tests
+#   Here we setup and teardown configuration required to run
+#   xdping, exercising its options.
+#
+#   Setup is similar to test_tunnel tests but without the tunnel.
+#
+# Topology:
+# ---------
+#     root namespace   |     tc_ns0 namespace
+#                      |
+#      ----------      |     ----------
+#      |  veth1  | --------- |  veth0  |
+#      ----------    peer    ----------
+#
+# Device Configuration
+# --------------------
+# Root namespace with BPF
+# Device names and addresses:
+#	veth1 IP: 10.1.1.200
+#	xdp added to veth1, xdpings originate from here.
+#
+# Namespace tc_ns0 with BPF
+# Device names and addresses:
+#       veth0 IPv4: 10.1.1.100
+#	For some tests xdping run in server mode here.
+#
+
+readonly TARGET_IP="10.1.1.100"
+readonly TARGET_NS="xdp_ns0"
+
+readonly LOCAL_IP="10.1.1.200"
+
+setup()
+{
+	ip netns add $TARGET_NS
+	ip link add veth0 type veth peer name veth1
+	ip link set veth0 netns $TARGET_NS
+	ip netns exec $TARGET_NS ip addr add ${TARGET_IP}/24 dev veth0
+	ip addr add ${LOCAL_IP}/24 dev veth1
+	ip netns exec $TARGET_NS ip link set veth0 up
+	ip link set veth1 up
+}
+
+cleanup()
+{
+	set +e
+	ip netns delete $TARGET_NS 2>/dev/null
+	ip link del veth1 2>/dev/null
+	if [[ $server_pid -ne 0 ]]; then
+		kill -TERM $server_pid
+	fi
+}
+
+test()
+{
+	client_args="$1"
+	server_args="$2"
+
+	echo "Test client args '$client_args'; server args '$server_args'"
+
+	server_pid=0
+	if [[ -n "$server_args" ]]; then
+		ip netns exec $TARGET_NS ./xdping $server_args &
+		server_pid=$!
+		sleep 10
+	fi
+	./xdping $client_args $TARGET_IP
+
+	if [[ $server_pid -ne 0 ]]; then
+		kill -TERM $server_pid
+		server_pid=0
+	fi
+
+	echo "Test client args '$client_args'; server args '$server_args': PASS"
+}
+
+set -e
+
+server_pid=0
+
+trap cleanup EXIT
+
+setup
+
+for server_args in "" "-I veth0 -s -S" ; do
+	# client in skb mode
+	client_args="-I veth1 -S"
+	test "$client_args" "$server_args"
+
+	# client with count of 10 RTT measurements.
+	client_args="-I veth1 -S -c 10"
+	test "$client_args" "$server_args"
+done
+
+echo "OK. All tests passed"
+exit 0
diff --git a/tools/testing/selftests/bpf/trace_helpers.c b/tools/testing/selftests/bpf/trace_helpers.c
index 9a9fc6c9b70b..b47f205f0310 100644
--- a/tools/testing/selftests/bpf/trace_helpers.c
+++ b/tools/testing/selftests/bpf/trace_helpers.c
@@ -30,9 +30,7 @@ int load_kallsyms(void)
 	if (!f)
 		return -ENOENT;
 
-	while (!feof(f)) {
-		if (!fgets(buf, sizeof(buf), f))
-			break;
+	while (fgets(buf, sizeof(buf), f)) {
 		if (sscanf(buf, "%p %c %s", &addr, &symbol, func) != 3)
 			break;
 		if (!addr)
diff --git a/tools/testing/selftests/bpf/xdping.c b/tools/testing/selftests/bpf/xdping.c
new file mode 100644
index 000000000000..d60a343b1371
--- /dev/null
+++ b/tools/testing/selftests/bpf/xdping.c
@@ -0,0 +1,258 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2019, Oracle and/or its affiliates. All rights reserved. */
+
+#include <linux/bpf.h>
+#include <linux/if_link.h>
+#include <arpa/inet.h>
+#include <assert.h>
+#include <errno.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <libgen.h>
+#include <sys/resource.h>
+#include <net/if.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <netdb.h>
+
+#include "bpf/bpf.h"
+#include "bpf/libbpf.h"
+
+#include "xdping.h"
+
+static int ifindex;
+static __u32 xdp_flags = XDP_FLAGS_UPDATE_IF_NOEXIST;
+
+static void cleanup(int sig)
+{
+	bpf_set_link_xdp_fd(ifindex, -1, xdp_flags);
+	if (sig)
+		exit(1);
+}
+
+static int get_stats(int fd, __u16 count, __u32 raddr)
+{
+	struct pinginfo pinginfo = { 0 };
+	char inaddrbuf[INET_ADDRSTRLEN];
+	struct in_addr inaddr;
+	__u16 i;
+
+	inaddr.s_addr = raddr;
+
+	printf("\nXDP RTT data:\n");
+
+	if (bpf_map_lookup_elem(fd, &raddr, &pinginfo)) {
+		perror("bpf_map_lookup elem: ");
+		return 1;
+	}
+
+	for (i = 0; i < count; i++) {
+		if (pinginfo.times[i] == 0)
+			break;
+
+		printf("64 bytes from %s: icmp_seq=%d ttl=64 time=%#.5f ms\n",
+		       inet_ntop(AF_INET, &inaddr, inaddrbuf,
+				 sizeof(inaddrbuf)),
+		       count + i + 1,
+		       (double)pinginfo.times[i]/1000000);
+	}
+
+	if (i < count) {
+		fprintf(stderr, "Expected %d samples, got %d.\n", count, i);
+		return 1;
+	}
+
+	bpf_map_delete_elem(fd, &raddr);
+
+	return 0;
+}
+
+static void show_usage(const char *prog)
+{
+	fprintf(stderr,
+		"usage: %s [OPTS] -I interface destination\n\n"
+		"OPTS:\n"
+		"    -c count		Stop after sending count requests\n"
+		"			(default %d, max %d)\n"
+		"    -I interface	interface name\n"
+		"    -N			Run in driver mode\n"
+		"    -s			Server mode\n"
+		"    -S			Run in skb mode\n",
+		prog, XDPING_DEFAULT_COUNT, XDPING_MAX_COUNT);
+}
+
+int main(int argc, char **argv)
+{
+	__u32 mode_flags = XDP_FLAGS_DRV_MODE | XDP_FLAGS_SKB_MODE;
+	struct addrinfo *a, hints = { .ai_family = AF_INET };
+	struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
+	__u16 count = XDPING_DEFAULT_COUNT;
+	struct pinginfo pinginfo = { 0 };
+	const char *optstr = "c:I:NsS";
+	struct bpf_program *main_prog;
+	int prog_fd = -1, map_fd = -1;
+	struct sockaddr_in rin;
+	struct bpf_object *obj;
+	struct bpf_map *map;
+	char *ifname = NULL;
+	char filename[256];
+	int opt, ret = 1;
+	__u32 raddr = 0;
+	int server = 0;
+	char cmd[256];
+
+	while ((opt = getopt(argc, argv, optstr)) != -1) {
+		switch (opt) {
+		case 'c':
+			count = atoi(optarg);
+			if (count < 1 || count > XDPING_MAX_COUNT) {
+				fprintf(stderr,
+					"min count is 1, max count is %d\n",
+					XDPING_MAX_COUNT);
+				return 1;
+			}
+			break;
+		case 'I':
+			ifname = optarg;
+			ifindex = if_nametoindex(ifname);
+			if (!ifindex) {
+				fprintf(stderr, "Could not get interface %s\n",
+					ifname);
+				return 1;
+			}
+			break;
+		case 'N':
+			xdp_flags |= XDP_FLAGS_DRV_MODE;
+			break;
+		case 's':
+			/* use server program */
+			server = 1;
+			break;
+		case 'S':
+			xdp_flags |= XDP_FLAGS_SKB_MODE;
+			break;
+		default:
+			show_usage(basename(argv[0]));
+			return 1;
+		}
+	}
+
+	if (!ifname) {
+		show_usage(basename(argv[0]));
+		return 1;
+	}
+	if (!server && optind == argc) {
+		show_usage(basename(argv[0]));
+		return 1;
+	}
+
+	if ((xdp_flags & mode_flags) == mode_flags) {
+		fprintf(stderr, "-N or -S can be specified, not both.\n");
+		show_usage(basename(argv[0]));
+		return 1;
+	}
+
+	if (!server) {
+		/* Only supports IPv4; see hints initiailization above. */
+		if (getaddrinfo(argv[optind], NULL, &hints, &a) || !a) {
+			fprintf(stderr, "Could not resolve %s\n", argv[optind]);
+			return 1;
+		}
+		memcpy(&rin, a->ai_addr, sizeof(rin));
+		raddr = rin.sin_addr.s_addr;
+		freeaddrinfo(a);
+	}
+
+	if (setrlimit(RLIMIT_MEMLOCK, &r)) {
+		perror("setrlimit(RLIMIT_MEMLOCK)");
+		return 1;
+	}
+
+	snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
+
+	if (bpf_prog_load(filename, BPF_PROG_TYPE_XDP, &obj, &prog_fd)) {
+		fprintf(stderr, "load of %s failed\n", filename);
+		return 1;
+	}
+
+	main_prog = bpf_object__find_program_by_title(obj,
+						      server ? "xdpserver" :
+							       "xdpclient");
+	if (main_prog)
+		prog_fd = bpf_program__fd(main_prog);
+	if (!main_prog || prog_fd < 0) {
+		fprintf(stderr, "could not find xdping program");
+		return 1;
+	}
+
+	map = bpf_map__next(NULL, obj);
+	if (map)
+		map_fd = bpf_map__fd(map);
+	if (!map || map_fd < 0) {
+		fprintf(stderr, "Could not find ping map");
+		goto done;
+	}
+
+	signal(SIGINT, cleanup);
+	signal(SIGTERM, cleanup);
+
+	printf("Setting up XDP for %s, please wait...\n", ifname);
+
+	printf("XDP setup disrupts network connectivity, hit Ctrl+C to quit\n");
+
+	if (bpf_set_link_xdp_fd(ifindex, prog_fd, xdp_flags) < 0) {
+		fprintf(stderr, "Link set xdp fd failed for %s\n", ifname);
+		goto done;
+	}
+
+	if (server) {
+		close(prog_fd);
+		close(map_fd);
+		printf("Running server on %s; press Ctrl+C to exit...\n",
+		       ifname);
+		do { } while (1);
+	}
+
+	/* Start xdping-ing from last regular ping reply, e.g. for a count
+	 * of 10 ICMP requests, we start xdping-ing using reply with seq number
+	 * 10.  The reason the last "real" ping RTT is much higher is that
+	 * the ping program sees the ICMP reply associated with the last
+	 * XDP-generated packet, so ping doesn't get a reply until XDP is done.
+	 */
+	pinginfo.seq = htons(count);
+	pinginfo.count = count;
+
+	if (bpf_map_update_elem(map_fd, &raddr, &pinginfo, BPF_ANY)) {
+		fprintf(stderr, "could not communicate with BPF map: %s\n",
+			strerror(errno));
+		cleanup(0);
+		goto done;
+	}
+
+	/* We need to wait for XDP setup to complete. */
+	sleep(10);
+
+	snprintf(cmd, sizeof(cmd), "ping -c %d -I %s %s",
+		 count, ifname, argv[optind]);
+
+	printf("\nNormal ping RTT data\n");
+	printf("[Ignore final RTT; it is distorted by XDP using the reply]\n");
+
+	ret = system(cmd);
+
+	if (!ret)
+		ret = get_stats(map_fd, count, raddr);
+
+	cleanup(0);
+
+done:
+	if (prog_fd > 0)
+		close(prog_fd);
+	if (map_fd > 0)
+		close(map_fd);
+
+	return ret;
+}
diff --git a/tools/testing/selftests/bpf/xdping.h b/tools/testing/selftests/bpf/xdping.h
new file mode 100644
index 000000000000..afc578df77be
--- /dev/null
+++ b/tools/testing/selftests/bpf/xdping.h
@@ -0,0 +1,13 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/* Copyright (c) 2019, Oracle and/or its affiliates. All rights reserved. */
+
+#define	XDPING_MAX_COUNT	10
+#define	XDPING_DEFAULT_COUNT	4
+
+struct pinginfo {
+	__u64	start;
+	__be16	seq;
+	__u16	count;
+	__u32	pad;
+	__u64	times[XDPING_MAX_COUNT];
+};