Mgerge remote-tracking branch 'torvalds/master' into perf/core

To sync headers, for instance, in this case tools/perf was ahead of
upstream till Linus merged tip/perf/core to get the
PERF_RECORD_TEXT_POKE changes:

  Warning: Kernel ABI header at 'tools/include/uapi/linux/perf_event.h' differs from latest version at 'include/uapi/linux/perf_event.h'
  diff -u tools/include/uapi/linux/perf_event.h include/uapi/linux/perf_event.h

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

13 files changed, 843 insertions, 310 deletions

diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c
index a7329b671c41..eab14c97c15d 100644
--- a/tools/lib/bpf/bpf.c
+++ b/tools/lib/bpf/bpf.c
@@ -598,10 +598,21 @@ int bpf_link_create(int prog_fd, int target_fd,
 	attr.link_create.prog_fd = prog_fd;
 	attr.link_create.target_fd = target_fd;
 	attr.link_create.attach_type = attach_type;
+	attr.link_create.flags = OPTS_GET(opts, flags, 0);
 
 	return sys_bpf(BPF_LINK_CREATE, &attr, sizeof(attr));
 }
 
+int bpf_link_detach(int link_fd)
+{
+	union bpf_attr attr;
+
+	memset(&attr, 0, sizeof(attr));
+	attr.link_detach.link_fd = link_fd;
+
+	return sys_bpf(BPF_LINK_DETACH, &attr, sizeof(attr));
+}
+
 int bpf_link_update(int link_fd, int new_prog_fd,
 		    const struct bpf_link_update_opts *opts)
 {
diff --git a/tools/lib/bpf/bpf.h b/tools/lib/bpf/bpf.h
index dbef24ebcfcb..28855fd5b5f4 100644
--- a/tools/lib/bpf/bpf.h
+++ b/tools/lib/bpf/bpf.h
@@ -170,13 +170,16 @@ LIBBPF_API int bpf_prog_detach2(int prog_fd, int attachable_fd,
 
 struct bpf_link_create_opts {
 	size_t sz; /* size of this struct for forward/backward compatibility */
+	__u32 flags;
 };
-#define bpf_link_create_opts__last_field sz
+#define bpf_link_create_opts__last_field flags
 
 LIBBPF_API int bpf_link_create(int prog_fd, int target_fd,
 			       enum bpf_attach_type attach_type,
 			       const struct bpf_link_create_opts *opts);
 
+LIBBPF_API int bpf_link_detach(int link_fd);
+
 struct bpf_link_update_opts {
 	size_t sz; /* size of this struct for forward/backward compatibility */
 	__u32 flags;	   /* extra flags */
diff --git a/tools/lib/bpf/bpf_core_read.h b/tools/lib/bpf/bpf_core_read.h
index 7009dc90e012..eae5cccff761 100644
--- a/tools/lib/bpf/bpf_core_read.h
+++ b/tools/lib/bpf/bpf_core_read.h
@@ -217,7 +217,7 @@ enum bpf_field_info_kind {
  */
 #define BPF_CORE_READ_INTO(dst, src, a, ...)				    \
 	({								    \
-		___core_read(bpf_core_read, dst, src, a, ##__VA_ARGS__)	    \
+		___core_read(bpf_core_read, dst, (src), a, ##__VA_ARGS__)   \
 	})
 
 /*
@@ -227,7 +227,7 @@ enum bpf_field_info_kind {
  */
 #define BPF_CORE_READ_STR_INTO(dst, src, a, ...)			    \
 	({								    \
-		___core_read(bpf_core_read_str, dst, src, a, ##__VA_ARGS__) \
+		___core_read(bpf_core_read_str, dst, (src), a, ##__VA_ARGS__)\
 	})
 
 /*
@@ -254,8 +254,8 @@ enum bpf_field_info_kind {
  */
 #define BPF_CORE_READ(src, a, ...)					    \
 	({								    \
-		___type(src, a, ##__VA_ARGS__) __r;			    \
-		BPF_CORE_READ_INTO(&__r, src, a, ##__VA_ARGS__);	    \
+		___type((src), a, ##__VA_ARGS__) __r;			    \
+		BPF_CORE_READ_INTO(&__r, (src), a, ##__VA_ARGS__);	    \
 		__r;							    \
 	})
 
diff --git a/tools/lib/bpf/bpf_endian.h b/tools/lib/bpf/bpf_endian.h
index fbe28008450f..ec9db4feca9f 100644
--- a/tools/lib/bpf/bpf_endian.h
+++ b/tools/lib/bpf/bpf_endian.h
@@ -2,8 +2,35 @@
 #ifndef __BPF_ENDIAN__
 #define __BPF_ENDIAN__
 
-#include <linux/stddef.h>
-#include <linux/swab.h>
+/*
+ * Isolate byte #n and put it into byte #m, for __u##b type.
+ * E.g., moving byte #6 (nnnnnnnn) into byte #1 (mmmmmmmm) for __u64:
+ * 1) xxxxxxxx nnnnnnnn xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx mmmmmmmm xxxxxxxx
+ * 2) nnnnnnnn xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx mmmmmmmm xxxxxxxx 00000000
+ * 3) 00000000 00000000 00000000 00000000 00000000 00000000 00000000 nnnnnnnn
+ * 4) 00000000 00000000 00000000 00000000 00000000 00000000 nnnnnnnn 00000000
+ */
+#define ___bpf_mvb(x, b, n, m) ((__u##b)(x) << (b-(n+1)*8) >> (b-8) << (m*8))
+
+#define ___bpf_swab16(x) ((__u16)(			\
+			  ___bpf_mvb(x, 16, 0, 1) |	\
+			  ___bpf_mvb(x, 16, 1, 0)))
+
+#define ___bpf_swab32(x) ((__u32)(			\
+			  ___bpf_mvb(x, 32, 0, 3) |	\
+			  ___bpf_mvb(x, 32, 1, 2) |	\
+			  ___bpf_mvb(x, 32, 2, 1) |	\
+			  ___bpf_mvb(x, 32, 3, 0)))
+
+#define ___bpf_swab64(x) ((__u64)(			\
+			  ___bpf_mvb(x, 64, 0, 7) |	\
+			  ___bpf_mvb(x, 64, 1, 6) |	\
+			  ___bpf_mvb(x, 64, 2, 5) |	\
+			  ___bpf_mvb(x, 64, 3, 4) |	\
+			  ___bpf_mvb(x, 64, 4, 3) |	\
+			  ___bpf_mvb(x, 64, 5, 2) |	\
+			  ___bpf_mvb(x, 64, 6, 1) |	\
+			  ___bpf_mvb(x, 64, 7, 0)))
 
 /* LLVM's BPF target selects the endianness of the CPU
  * it compiles on, or the user specifies (bpfel/bpfeb),
@@ -23,16 +50,16 @@
 #if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
 # define __bpf_ntohs(x)			__builtin_bswap16(x)
 # define __bpf_htons(x)			__builtin_bswap16(x)
-# define __bpf_constant_ntohs(x)	___constant_swab16(x)
-# define __bpf_constant_htons(x)	___constant_swab16(x)
+# define __bpf_constant_ntohs(x)	___bpf_swab16(x)
+# define __bpf_constant_htons(x)	___bpf_swab16(x)
 # define __bpf_ntohl(x)			__builtin_bswap32(x)
 # define __bpf_htonl(x)			__builtin_bswap32(x)
-# define __bpf_constant_ntohl(x)	___constant_swab32(x)
-# define __bpf_constant_htonl(x)	___constant_swab32(x)
+# define __bpf_constant_ntohl(x)	___bpf_swab32(x)
+# define __bpf_constant_htonl(x)	___bpf_swab32(x)
 # define __bpf_be64_to_cpu(x)		__builtin_bswap64(x)
 # define __bpf_cpu_to_be64(x)		__builtin_bswap64(x)
-# define __bpf_constant_be64_to_cpu(x)	___constant_swab64(x)
-# define __bpf_constant_cpu_to_be64(x)	___constant_swab64(x)
+# define __bpf_constant_be64_to_cpu(x)	___bpf_swab64(x)
+# define __bpf_constant_cpu_to_be64(x)	___bpf_swab64(x)
 #elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
 # define __bpf_ntohs(x)			(x)
 # define __bpf_htons(x)			(x)
diff --git a/tools/lib/bpf/bpf_helpers.h b/tools/lib/bpf/bpf_helpers.h
index f67dce2af802..bc14db706b88 100644
--- a/tools/lib/bpf/bpf_helpers.h
+++ b/tools/lib/bpf/bpf_helpers.h
@@ -40,7 +40,7 @@
  * Helper macro to manipulate data structures
  */
 #ifndef offsetof
-#define offsetof(TYPE, MEMBER)  ((size_t)&((TYPE *)0)->MEMBER)
+#define offsetof(TYPE, MEMBER)  __builtin_offsetof(TYPE, MEMBER)
 #endif
 #ifndef container_of
 #define container_of(ptr, type, member)				\
@@ -75,5 +75,6 @@ enum libbpf_tristate {
 };
 
 #define __kconfig __attribute__((section(".kconfig")))
+#define __ksym __attribute__((section(".ksyms")))
 
 #endif
diff --git a/tools/lib/bpf/bpf_tracing.h b/tools/lib/bpf/bpf_tracing.h
index 58eceb884df3..eebf020cbe3e 100644
--- a/tools/lib/bpf/bpf_tracing.h
+++ b/tools/lib/bpf/bpf_tracing.h
@@ -215,7 +215,7 @@ struct pt_regs;
 #define PT_REGS_PARM5(x) ((x)->regs[8])
 #define PT_REGS_RET(x) ((x)->regs[31])
 #define PT_REGS_FP(x) ((x)->regs[30]) /* Works only with CONFIG_FRAME_POINTER */
-#define PT_REGS_RC(x) ((x)->regs[1])
+#define PT_REGS_RC(x) ((x)->regs[2])
 #define PT_REGS_SP(x) ((x)->regs[29])
 #define PT_REGS_IP(x) ((x)->cp0_epc)
 
@@ -226,7 +226,7 @@ struct pt_regs;
 #define PT_REGS_PARM5_CORE(x) BPF_CORE_READ((x), regs[8])
 #define PT_REGS_RET_CORE(x) BPF_CORE_READ((x), regs[31])
 #define PT_REGS_FP_CORE(x) BPF_CORE_READ((x), regs[30])
-#define PT_REGS_RC_CORE(x) BPF_CORE_READ((x), regs[1])
+#define PT_REGS_RC_CORE(x) BPF_CORE_READ((x), regs[2])
 #define PT_REGS_SP_CORE(x) BPF_CORE_READ((x), regs[29])
 #define PT_REGS_IP_CORE(x) BPF_CORE_READ((x), cp0_epc)
 
diff --git a/tools/lib/bpf/btf.c b/tools/lib/bpf/btf.c
index bfef3d606b54..856b09a04563 100644
--- a/tools/lib/bpf/btf.c
+++ b/tools/lib/bpf/btf.c
@@ -386,10 +386,10 @@ __s32 btf__find_by_name_kind(const struct btf *btf, const char *type_name,
 
 void btf__free(struct btf *btf)
 {
-	if (!btf)
+	if (IS_ERR_OR_NULL(btf))
 		return;
 
-	if (btf->fd != -1)
+	if (btf->fd >= 0)
 		close(btf->fd);
 
 	free(btf->data);
@@ -397,7 +397,7 @@ void btf__free(struct btf *btf)
 	free(btf);
 }
 
-struct btf *btf__new(__u8 *data, __u32 size)
+struct btf *btf__new(const void *data, __u32 size)
 {
 	struct btf *btf;
 	int err;
@@ -562,6 +562,83 @@ done:
 	return btf;
 }
 
+struct btf *btf__parse_raw(const char *path)
+{
+	void *data = NULL;
+	struct btf *btf;
+	FILE *f = NULL;
+	__u16 magic;
+	int err = 0;
+	long sz;
+
+	f = fopen(path, "rb");
+	if (!f) {
+		err = -errno;
+		goto err_out;
+	}
+
+	/* check BTF magic */
+	if (fread(&magic, 1, sizeof(magic), f) < sizeof(magic)) {
+		err = -EIO;
+		goto err_out;
+	}
+	if (magic != BTF_MAGIC) {
+		/* definitely not a raw BTF */
+		err = -EPROTO;
+		goto err_out;
+	}
+
+	/* get file size */
+	if (fseek(f, 0, SEEK_END)) {
+		err = -errno;
+		goto err_out;
+	}
+	sz = ftell(f);
+	if (sz < 0) {
+		err = -errno;
+		goto err_out;
+	}
+	/* rewind to the start */
+	if (fseek(f, 0, SEEK_SET)) {
+		err = -errno;
+		goto err_out;
+	}
+
+	/* pre-alloc memory and read all of BTF data */
+	data = malloc(sz);
+	if (!data) {
+		err = -ENOMEM;
+		goto err_out;
+	}
+	if (fread(data, 1, sz, f) < sz) {
+		err = -EIO;
+		goto err_out;
+	}
+
+	/* finally parse BTF data */
+	btf = btf__new(data, sz);
+
+err_out:
+	free(data);
+	if (f)
+		fclose(f);
+	return err ? ERR_PTR(err) : btf;
+}
+
+struct btf *btf__parse(const char *path, struct btf_ext **btf_ext)
+{
+	struct btf *btf;
+
+	if (btf_ext)
+		*btf_ext = NULL;
+
+	btf = btf__parse_raw(path);
+	if (!IS_ERR(btf) || PTR_ERR(btf) != -EPROTO)
+		return btf;
+
+	return btf__parse_elf(path, btf_ext);
+}
+
 static int compare_vsi_off(const void *_a, const void *_b)
 {
 	const struct btf_var_secinfo *a = _a;
@@ -700,6 +777,11 @@ int btf__fd(const struct btf *btf)
 	return btf->fd;
 }
 
+void btf__set_fd(struct btf *btf, int fd)
+{
+	btf->fd = fd;
+}
+
 const void *btf__get_raw_data(const struct btf *btf, __u32 *size)
 {
 	*size = btf->data_size;
@@ -1020,7 +1102,7 @@ static int btf_ext_parse_hdr(__u8 *data, __u32 data_size)
 
 void btf_ext__free(struct btf_ext *btf_ext)
 {
-	if (!btf_ext)
+	if (IS_ERR_OR_NULL(btf_ext))
 		return;
 	free(btf_ext->data);
 	free(btf_ext);
@@ -2946,41 +3028,6 @@ static int btf_dedup_remap_types(struct btf_dedup *d)
 	return 0;
 }
 
-static struct btf *btf_load_raw(const char *path)
-{
-	struct btf *btf;
-	size_t read_cnt;
-	struct stat st;
-	void *data;
-	FILE *f;
-
-	if (stat(path, &st))
-		return ERR_PTR(-errno);
-
-	data = malloc(st.st_size);
-	if (!data)
-		return ERR_PTR(-ENOMEM);
-
-	f = fopen(path, "rb");
-	if (!f) {
-		btf = ERR_PTR(-errno);
-		goto cleanup;
-	}
-
-	read_cnt = fread(data, 1, st.st_size, f);
-	fclose(f);
-	if (read_cnt < st.st_size) {
-		btf = ERR_PTR(-EBADF);
-		goto cleanup;
-	}
-
-	btf = btf__new(data, read_cnt);
-
-cleanup:
-	free(data);
-	return btf;
-}
-
 /*
  * Probe few well-known locations for vmlinux kernel image and try to load BTF
  * data out of it to use for target BTF.
@@ -3016,7 +3063,7 @@ struct btf *libbpf_find_kernel_btf(void)
 			continue;
 
 		if (locations[i].raw_btf)
-			btf = btf_load_raw(path);
+			btf = btf__parse_raw(path);
 		else
 			btf = btf__parse_elf(path, NULL);
 
diff --git a/tools/lib/bpf/btf.h b/tools/lib/bpf/btf.h
index 70c1b7ec2bd0..f4a1a1d2b9a3 100644
--- a/tools/lib/bpf/btf.h
+++ b/tools/lib/bpf/btf.h
@@ -63,9 +63,10 @@ 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 struct btf *btf__new(const void *data, __u32 size);
+LIBBPF_API struct btf *btf__parse(const char *path, struct btf_ext **btf_ext);
+LIBBPF_API struct btf *btf__parse_elf(const char *path, struct btf_ext **btf_ext);
+LIBBPF_API struct btf *btf__parse_raw(const char *path);
 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,
@@ -79,6 +80,7 @@ LIBBPF_API __s64 btf__resolve_size(const struct btf *btf, __u32 type_id);
 LIBBPF_API int btf__resolve_type(const struct btf *btf, __u32 type_id);
 LIBBPF_API int btf__align_of(const struct btf *btf, __u32 id);
 LIBBPF_API int btf__fd(const struct btf *btf);
+LIBBPF_API void btf__set_fd(struct btf *btf, int fd);
 LIBBPF_API const void *btf__get_raw_data(const struct btf *btf, __u32 *size);
 LIBBPF_API const char *btf__name_by_offset(const struct btf *btf, __u32 offset);
 LIBBPF_API int btf__get_from_id(__u32 id, struct btf **btf);
@@ -143,8 +145,10 @@ struct btf_dump_emit_type_decl_opts {
 	 * necessary indentation already
 	 */
 	int indent_level;
+	/* strip all the const/volatile/restrict mods */
+	bool strip_mods;
 };
-#define btf_dump_emit_type_decl_opts__last_field indent_level
+#define btf_dump_emit_type_decl_opts__last_field strip_mods
 
 LIBBPF_API int
 btf_dump__emit_type_decl(struct btf_dump *d, __u32 id,
@@ -168,6 +172,11 @@ static inline bool btf_kflag(const struct btf_type *t)
 	return BTF_INFO_KFLAG(t->info);
 }
 
+static inline bool btf_is_void(const struct btf_type *t)
+{
+	return btf_kind(t) == BTF_KIND_UNKN;
+}
+
 static inline bool btf_is_int(const struct btf_type *t)
 {
 	return btf_kind(t) == BTF_KIND_INT;
diff --git a/tools/lib/bpf/btf_dump.c b/tools/lib/bpf/btf_dump.c
index bbb430317260..cf711168d34a 100644
--- a/tools/lib/bpf/btf_dump.c
+++ b/tools/lib/bpf/btf_dump.c
@@ -60,6 +60,7 @@ struct btf_dump {
 	const struct btf_ext *btf_ext;
 	btf_dump_printf_fn_t printf_fn;
 	struct btf_dump_opts opts;
+	bool strip_mods;
 
 	/* per-type auxiliary state */
 	struct btf_dump_type_aux_state *type_states;
@@ -182,7 +183,7 @@ void btf_dump__free(struct btf_dump *d)
 {
 	int i, cnt;
 
-	if (!d)
+	if (IS_ERR_OR_NULL(d))
 		return;
 
 	free(d->type_states);
@@ -1032,7 +1033,9 @@ int btf_dump__emit_type_decl(struct btf_dump *d, __u32 id,
 
 	fname = OPTS_GET(opts, field_name, "");
 	lvl = OPTS_GET(opts, indent_level, 0);
+	d->strip_mods = OPTS_GET(opts, strip_mods, false);
 	btf_dump_emit_type_decl(d, id, fname, lvl);
+	d->strip_mods = false;
 	return 0;
 }
 
@@ -1045,6 +1048,10 @@ static void btf_dump_emit_type_decl(struct btf_dump *d, __u32 id,
 
 	stack_start = d->decl_stack_cnt;
 	for (;;) {
+		t = btf__type_by_id(d->btf, id);
+		if (d->strip_mods && btf_is_mod(t))
+			goto skip_mod;
+
 		err = btf_dump_push_decl_stack_id(d, id);
 		if (err < 0) {
 			/*
@@ -1056,12 +1063,11 @@ static void btf_dump_emit_type_decl(struct btf_dump *d, __u32 id,
 			d->decl_stack_cnt = stack_start;
 			return;
 		}
-
+skip_mod:
 		/* VOID */
 		if (id == 0)
 			break;
 
-		t = btf__type_by_id(d->btf, id);
 		switch (btf_kind(t)) {
 		case BTF_KIND_PTR:
 		case BTF_KIND_VOLATILE:
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 11e4725b8b1c..7be04e45d29c 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -230,6 +230,7 @@ struct bpf_program {
 	struct bpf_insn *insns;
 	size_t insns_cnt, main_prog_cnt;
 	enum bpf_prog_type type;
+	bool load;
 
 	struct reloc_desc *reloc_desc;
 	int nr_reloc;
@@ -285,6 +286,7 @@ struct bpf_struct_ops {
 #define BSS_SEC ".bss"
 #define RODATA_SEC ".rodata"
 #define KCONFIG_SEC ".kconfig"
+#define KSYMS_SEC ".ksyms"
 #define STRUCT_OPS_SEC ".struct_ops"
 
 enum libbpf_map_type {
@@ -310,6 +312,7 @@ struct bpf_map {
 	int map_ifindex;
 	int inner_map_fd;
 	struct bpf_map_def def;
+	__u32 numa_node;
 	__u32 btf_var_idx;
 	__u32 btf_key_type_id;
 	__u32 btf_value_type_id;
@@ -329,24 +332,39 @@ struct bpf_map {
 
 enum extern_type {
 	EXT_UNKNOWN,
-	EXT_CHAR,
-	EXT_BOOL,
-	EXT_INT,
-	EXT_TRISTATE,
-	EXT_CHAR_ARR,
+	EXT_KCFG,
+	EXT_KSYM,
+};
+
+enum kcfg_type {
+	KCFG_UNKNOWN,
+	KCFG_CHAR,
+	KCFG_BOOL,
+	KCFG_INT,
+	KCFG_TRISTATE,
+	KCFG_CHAR_ARR,
 };
 
 struct extern_desc {
-	const char *name;
+	enum extern_type type;
 	int sym_idx;
 	int btf_id;
-	enum extern_type type;
-	int sz;
-	int align;
-	int data_off;
-	bool is_signed;
-	bool is_weak;
+	int sec_btf_id;
+	const char *name;
 	bool is_set;
+	bool is_weak;
+	union {
+		struct {
+			enum kcfg_type type;
+			int sz;
+			int align;
+			int data_off;
+			bool is_signed;
+		} kcfg;
+		struct {
+			unsigned long long addr;
+		} ksym;
+	};
 };
 
 static LIST_HEAD(bpf_objects_list);
@@ -524,6 +542,7 @@ bpf_program__init(void *data, size_t size, char *section_name, int idx,
 	prog->instances.fds = NULL;
 	prog->instances.nr = -1;
 	prog->type = BPF_PROG_TYPE_UNSPEC;
+	prog->load = true;
 
 	return 0;
 errout:
@@ -1423,19 +1442,19 @@ static struct extern_desc *find_extern_by_name(const struct bpf_object *obj,
 	return NULL;
 }
 
-static int set_ext_value_tri(struct extern_desc *ext, void *ext_val,
-			     char value)
+static int set_kcfg_value_tri(struct extern_desc *ext, void *ext_val,
+			      char value)
 {
-	switch (ext->type) {
-	case EXT_BOOL:
+	switch (ext->kcfg.type) {
+	case KCFG_BOOL:
 		if (value == 'm') {
-			pr_warn("extern %s=%c should be tristate or char\n",
+			pr_warn("extern (kcfg) %s=%c should be tristate or char\n",
 				ext->name, value);
 			return -EINVAL;
 		}
 		*(bool *)ext_val = value == 'y' ? true : false;
 		break;
-	case EXT_TRISTATE:
+	case KCFG_TRISTATE:
 		if (value == 'y')
 			*(enum libbpf_tristate *)ext_val = TRI_YES;
 		else if (value == 'm')
@@ -1443,14 +1462,14 @@ static int set_ext_value_tri(struct extern_desc *ext, void *ext_val,
 		else /* value == 'n' */
 			*(enum libbpf_tristate *)ext_val = TRI_NO;
 		break;
-	case EXT_CHAR:
+	case KCFG_CHAR:
 		*(char *)ext_val = value;
 		break;
-	case EXT_UNKNOWN:
-	case EXT_INT:
-	case EXT_CHAR_ARR:
+	case KCFG_UNKNOWN:
+	case KCFG_INT:
+	case KCFG_CHAR_ARR:
 	default:
-		pr_warn("extern %s=%c should be bool, tristate, or char\n",
+		pr_warn("extern (kcfg) %s=%c should be bool, tristate, or char\n",
 			ext->name, value);
 		return -EINVAL;
 	}
@@ -1458,29 +1477,29 @@ static int set_ext_value_tri(struct extern_desc *ext, void *ext_val,
 	return 0;
 }
 
-static int set_ext_value_str(struct extern_desc *ext, char *ext_val,
-			     const char *value)
+static int set_kcfg_value_str(struct extern_desc *ext, char *ext_val,
+			      const char *value)
 {
 	size_t len;
 
-	if (ext->type != EXT_CHAR_ARR) {
-		pr_warn("extern %s=%s should char array\n", ext->name, value);
+	if (ext->kcfg.type != KCFG_CHAR_ARR) {
+		pr_warn("extern (kcfg) %s=%s should be char array\n", ext->name, value);
 		return -EINVAL;
 	}
 
 	len = strlen(value);
 	if (value[len - 1] != '"') {
-		pr_warn("extern '%s': invalid string config '%s'\n",
+		pr_warn("extern (kcfg) '%s': invalid string config '%s'\n",
 			ext->name, value);
 		return -EINVAL;
 	}
 
 	/* strip quotes */
 	len -= 2;
-	if (len >= ext->sz) {
-		pr_warn("extern '%s': long string config %s of (%zu bytes) truncated to %d bytes\n",
-			ext->name, value, len, ext->sz - 1);
-		len = ext->sz - 1;
+	if (len >= ext->kcfg.sz) {
+		pr_warn("extern (kcfg) '%s': long string config %s of (%zu bytes) truncated to %d bytes\n",
+			ext->name, value, len, ext->kcfg.sz - 1);
+		len = ext->kcfg.sz - 1;
 	}
 	memcpy(ext_val, value + 1, len);
 	ext_val[len] = '\0';
@@ -1507,11 +1526,11 @@ static int parse_u64(const char *value, __u64 *res)
 	return 0;
 }
 
-static bool is_ext_value_in_range(const struct extern_desc *ext, __u64 v)
+static bool is_kcfg_value_in_range(const struct extern_desc *ext, __u64 v)
 {
-	int bit_sz = ext->sz * 8;
+	int bit_sz = ext->kcfg.sz * 8;
 
-	if (ext->sz == 8)
+	if (ext->kcfg.sz == 8)
 		return true;
 
 	/* Validate that value stored in u64 fits in integer of `ext->sz`
@@ -1526,26 +1545,26 @@ static bool is_ext_value_in_range(const struct extern_desc *ext, __u64 v)
 	 *  For unsigned target integer, check that all the (64 - Y) bits are
 	 *  zero.
 	 */
-	if (ext->is_signed)
+	if (ext->kcfg.is_signed)
 		return v + (1ULL << (bit_sz - 1)) < (1ULL << bit_sz);
 	else
 		return (v >> bit_sz) == 0;
 }
 
-static int set_ext_value_num(struct extern_desc *ext, void *ext_val,
-			     __u64 value)
+static int set_kcfg_value_num(struct extern_desc *ext, void *ext_val,
+			      __u64 value)
 {
-	if (ext->type != EXT_INT && ext->type != EXT_CHAR) {
-		pr_warn("extern %s=%llu should be integer\n",
+	if (ext->kcfg.type != KCFG_INT && ext->kcfg.type != KCFG_CHAR) {
+		pr_warn("extern (kcfg) %s=%llu should be integer\n",
 			ext->name, (unsigned long long)value);
 		return -EINVAL;
 	}
-	if (!is_ext_value_in_range(ext, value)) {
-		pr_warn("extern %s=%llu value doesn't fit in %d bytes\n",
-			ext->name, (unsigned long long)value, ext->sz);
+	if (!is_kcfg_value_in_range(ext, value)) {
+		pr_warn("extern (kcfg) %s=%llu value doesn't fit in %d bytes\n",
+			ext->name, (unsigned long long)value, ext->kcfg.sz);
 		return -ERANGE;
 	}
-	switch (ext->sz) {
+	switch (ext->kcfg.sz) {
 		case 1: *(__u8 *)ext_val = value; break;
 		case 2: *(__u16 *)ext_val = value; break;
 		case 4: *(__u32 *)ext_val = value; break;
@@ -1591,30 +1610,30 @@ static int bpf_object__process_kconfig_line(struct bpf_object *obj,
 	if (!ext || ext->is_set)
 		return 0;
 
-	ext_val = data + ext->data_off;
+	ext_val = data + ext->kcfg.data_off;
 	value = sep + 1;
 
 	switch (*value) {
 	case 'y': case 'n': case 'm':
-		err = set_ext_value_tri(ext, ext_val, *value);
+		err = set_kcfg_value_tri(ext, ext_val, *value);
 		break;
 	case '"':
-		err = set_ext_value_str(ext, ext_val, value);
+		err = set_kcfg_value_str(ext, ext_val, value);
 		break;
 	default:
 		/* assume integer */
 		err = parse_u64(value, &num);
 		if (err) {
-			pr_warn("extern %s=%s should be integer\n",
+			pr_warn("extern (kcfg) %s=%s should be integer\n",
 				ext->name, value);
 			return err;
 		}
-		err = set_ext_value_num(ext, ext_val, num);
+		err = set_kcfg_value_num(ext, ext_val, num);
 		break;
 	}
 	if (err)
 		return err;
-	pr_debug("extern %s=%s\n", ext->name, value);
+	pr_debug("extern (kcfg) %s=%s\n", ext->name, value);
 	return 0;
 }
 
@@ -1685,16 +1704,20 @@ static int bpf_object__read_kconfig_mem(struct bpf_object *obj,
 
 static int bpf_object__init_kconfig_map(struct bpf_object *obj)
 {
-	struct extern_desc *last_ext;
+	struct extern_desc *last_ext = NULL, *ext;
 	size_t map_sz;
-	int err;
+	int i, err;
 
-	if (obj->nr_extern == 0)
-		return 0;
+	for (i = 0; i < obj->nr_extern; i++) {
+		ext = &obj->externs[i];
+		if (ext->type == EXT_KCFG)
+			last_ext = ext;
+	}
 
-	last_ext = &obj->externs[obj->nr_extern - 1];
-	map_sz = last_ext->data_off + last_ext->sz;
+	if (!last_ext)
+		return 0;
 
+	map_sz = last_ext->kcfg.data_off + last_ext->kcfg.sz;
 	err = bpf_object__init_internal_map(obj, LIBBPF_MAP_KCONFIG,
 					    obj->efile.symbols_shndx,
 					    NULL, map_sz);
@@ -1957,6 +1980,10 @@ static int parse_btf_map_def(struct bpf_object *obj,
 				return -EINVAL;
 			pr_debug("map '%s': found map_flags = %u.\n",
 				 map->name, map->def.map_flags);
+		} else if (strcmp(name, "numa_node") == 0) {
+			if (!get_map_field_int(map->name, obj->btf, m, &map->numa_node))
+				return -EINVAL;
+			pr_debug("map '%s': found numa_node = %u.\n", map->name, map->numa_node);
 		} else if (strcmp(name, "key_size") == 0) {
 			__u32 sz;
 
@@ -2311,18 +2338,23 @@ static bool section_have_execinstr(struct bpf_object *obj, int idx)
 	return false;
 }
 
-static void bpf_object__sanitize_btf(struct bpf_object *obj)
+static bool btf_needs_sanitization(struct bpf_object *obj)
+{
+	bool has_func_global = obj->caps.btf_func_global;
+	bool has_datasec = obj->caps.btf_datasec;
+	bool has_func = obj->caps.btf_func;
+
+	return !has_func || !has_datasec || !has_func_global;
+}
+
+static void bpf_object__sanitize_btf(struct bpf_object *obj, struct btf *btf)
 {
 	bool has_func_global = obj->caps.btf_func_global;
 	bool has_datasec = obj->caps.btf_datasec;
 	bool has_func = obj->caps.btf_func;
-	struct btf *btf = obj->btf;
 	struct btf_type *t;
 	int i, j, vlen;
 
-	if (!obj->btf || (has_func && has_datasec && has_func_global))
-		return;
-
 	for (i = 1; i <= btf__get_nr_types(btf); i++) {
 		t = (struct btf_type *)btf__type_by_id(btf, i);
 
@@ -2375,17 +2407,6 @@ static void bpf_object__sanitize_btf(struct bpf_object *obj)
 	}
 }
 
-static void bpf_object__sanitize_btf_ext(struct bpf_object *obj)
-{
-	if (!obj->btf_ext)
-		return;
-
-	if (!obj->caps.btf_func) {
-		btf_ext__free(obj->btf_ext);
-		obj->btf_ext = NULL;
-	}
-}
-
 static bool libbpf_needs_btf(const struct bpf_object *obj)
 {
 	return obj->efile.btf_maps_shndx >= 0 ||
@@ -2446,19 +2467,11 @@ static int bpf_object__finalize_btf(struct bpf_object *obj)
 		return 0;
 
 	err = btf__finalize_data(obj, obj->btf);
-	if (!err)
-		return 0;
-
-	pr_warn("Error finalizing %s: %d.\n", BTF_ELF_SEC, err);
-	btf__free(obj->btf);
-	obj->btf = NULL;
-	btf_ext__free(obj->btf_ext);
-	obj->btf_ext = NULL;
-
-	if (libbpf_needs_btf(obj)) {
-		pr_warn("BTF is required, but is missing or corrupted.\n");
-		return -ENOENT;
+	if (err) {
+		pr_warn("Error finalizing %s: %d.\n", BTF_ELF_SEC, err);
+		return err;
 	}
+
 	return 0;
 }
 
@@ -2479,51 +2492,77 @@ static inline bool libbpf_prog_needs_vmlinux_btf(struct bpf_program *prog)
 
 static int bpf_object__load_vmlinux_btf(struct bpf_object *obj)
 {
+	bool need_vmlinux_btf = false;
 	struct bpf_program *prog;
 	int err;
 
+	/* CO-RE relocations need kernel BTF */
+	if (obj->btf_ext && obj->btf_ext->field_reloc_info.len)
+		need_vmlinux_btf = true;
+
 	bpf_object__for_each_program(prog, obj) {
+		if (!prog->load)
+			continue;
 		if (libbpf_prog_needs_vmlinux_btf(prog)) {
-			obj->btf_vmlinux = libbpf_find_kernel_btf();
-			if (IS_ERR(obj->btf_vmlinux)) {
-				err = PTR_ERR(obj->btf_vmlinux);
-				pr_warn("Error loading vmlinux BTF: %d\n", err);
-				obj->btf_vmlinux = NULL;
-				return err;
-			}
-			return 0;
+			need_vmlinux_btf = true;
+			break;
 		}
 	}
 
+	if (!need_vmlinux_btf)
+		return 0;
+
+	obj->btf_vmlinux = libbpf_find_kernel_btf();
+	if (IS_ERR(obj->btf_vmlinux)) {
+		err = PTR_ERR(obj->btf_vmlinux);
+		pr_warn("Error loading vmlinux BTF: %d\n", err);
+		obj->btf_vmlinux = NULL;
+		return err;
+	}
 	return 0;
 }
 
 static int bpf_object__sanitize_and_load_btf(struct bpf_object *obj)
 {
+	struct btf *kern_btf = obj->btf;
+	bool btf_mandatory, sanitize;
 	int err = 0;
 
 	if (!obj->btf)
 		return 0;
 
-	bpf_object__sanitize_btf(obj);
-	bpf_object__sanitize_btf_ext(obj);
+	sanitize = btf_needs_sanitization(obj);
+	if (sanitize) {
+		const void *raw_data;
+		__u32 sz;
 
-	err = btf__load(obj->btf);
-	if (err) {
-		pr_warn("Error loading %s into kernel: %d.\n",
-			BTF_ELF_SEC, err);
-		btf__free(obj->btf);
-		obj->btf = NULL;
-		/* btf_ext can't exist without btf, so free it as well */
-		if (obj->btf_ext) {
-			btf_ext__free(obj->btf_ext);
-			obj->btf_ext = NULL;
-		}
+		/* clone BTF to sanitize a copy and leave the original intact */
+		raw_data = btf__get_raw_data(obj->btf, &sz);
+		kern_btf = btf__new(raw_data, sz);
+		if (IS_ERR(kern_btf))
+			return PTR_ERR(kern_btf);
 
-		if (kernel_needs_btf(obj))
-			return err;
+		bpf_object__sanitize_btf(obj, kern_btf);
 	}
-	return 0;
+
+	err = btf__load(kern_btf);
+	if (sanitize) {
+		if (!err) {
+			/* move fd to libbpf's BTF */
+			btf__set_fd(obj->btf, btf__fd(kern_btf));
+			btf__set_fd(kern_btf, -1);
+		}
+		btf__free(kern_btf);
+	}
+	if (err) {
+		btf_mandatory = kernel_needs_btf(obj);
+		pr_warn("Error loading .BTF into kernel: %d. %s\n", err,
+			btf_mandatory ? "BTF is mandatory, can't proceed."
+				      : "BTF is optional, ignoring.");
+		if (!btf_mandatory)
+			err = 0;
+	}
+	return err;
 }
 
 static int bpf_object__elf_collect(struct bpf_object *obj)
@@ -2709,8 +2748,33 @@ static int find_extern_btf_id(const struct btf *btf, const char *ext_name)
 	return -ENOENT;
 }
 
-static enum extern_type find_extern_type(const struct btf *btf, int id,
-					 bool *is_signed)
+static int find_extern_sec_btf_id(struct btf *btf, int ext_btf_id) {
+	const struct btf_var_secinfo *vs;
+	const struct btf_type *t;
+	int i, j, n;
+
+	if (!btf)
+		return -ESRCH;
+
+	n = btf__get_nr_types(btf);
+	for (i = 1; i <= n; i++) {
+		t = btf__type_by_id(btf, i);
+
+		if (!btf_is_datasec(t))
+			continue;
+
+		vs = btf_var_secinfos(t);
+		for (j = 0; j < btf_vlen(t); j++, vs++) {
+			if (vs->type == ext_btf_id)
+				return i;
+		}
+	}
+
+	return -ENOENT;
+}
+
+static enum kcfg_type find_kcfg_type(const struct btf *btf, int id,
+				     bool *is_signed)
 {
 	const struct btf_type *t;
 	const char *name;
@@ -2725,29 +2789,29 @@ static enum extern_type find_extern_type(const struct btf *btf, int id,
 		int enc = btf_int_encoding(t);
 
 		if (enc & BTF_INT_BOOL)
-			return t->size == 1 ? EXT_BOOL : EXT_UNKNOWN;
+			return t->size == 1 ? KCFG_BOOL : KCFG_UNKNOWN;
 		if (is_signed)
 			*is_signed = enc & BTF_INT_SIGNED;
 		if (t->size == 1)
-			return EXT_CHAR;
+			return KCFG_CHAR;
 		if (t->size < 1 || t->size > 8 || (t->size & (t->size - 1)))
-			return EXT_UNKNOWN;
-		return EXT_INT;
+			return KCFG_UNKNOWN;
+		return KCFG_INT;
 	}
 	case BTF_KIND_ENUM:
 		if (t->size != 4)
-			return EXT_UNKNOWN;
+			return KCFG_UNKNOWN;
 		if (strcmp(name, "libbpf_tristate"))
-			return EXT_UNKNOWN;
-		return EXT_TRISTATE;
+			return KCFG_UNKNOWN;
+		return KCFG_TRISTATE;
 	case BTF_KIND_ARRAY:
 		if (btf_array(t)->nelems == 0)
-			return EXT_UNKNOWN;
-		if (find_extern_type(btf, btf_array(t)->type, NULL) != EXT_CHAR)
-			return EXT_UNKNOWN;
-		return EXT_CHAR_ARR;
+			return KCFG_UNKNOWN;
+		if (find_kcfg_type(btf, btf_array(t)->type, NULL) != KCFG_CHAR)
+			return KCFG_UNKNOWN;
+		return KCFG_CHAR_ARR;
 	default:
-		return EXT_UNKNOWN;
+		return KCFG_UNKNOWN;
 	}
 }
 
@@ -2756,23 +2820,45 @@ static int cmp_externs(const void *_a, const void *_b)
 	const struct extern_desc *a = _a;
 	const struct extern_desc *b = _b;
 
-	/* descending order by alignment requirements */
-	if (a->align != b->align)
-		return a->align > b->align ? -1 : 1;
-	/* ascending order by size, within same alignment class */
-	if (a->sz != b->sz)
-		return a->sz < b->sz ? -1 : 1;
+	if (a->type != b->type)
+		return a->type < b->type ? -1 : 1;
+
+	if (a->type == EXT_KCFG) {
+		/* descending order by alignment requirements */
+		if (a->kcfg.align != b->kcfg.align)
+			return a->kcfg.align > b->kcfg.align ? -1 : 1;
+		/* ascending order by size, within same alignment class */
+		if (a->kcfg.sz != b->kcfg.sz)
+			return a->kcfg.sz < b->kcfg.sz ? -1 : 1;
+	}
+
 	/* resolve ties by name */
 	return strcmp(a->name, b->name);
 }
 
+static int find_int_btf_id(const struct btf *btf)
+{
+	const struct btf_type *t;
+	int i, n;
+
+	n = btf__get_nr_types(btf);
+	for (i = 1; i <= n; i++) {
+		t = btf__type_by_id(btf, i);
+
+		if (btf_is_int(t) && btf_int_bits(t) == 32)
+			return i;
+	}
+
+	return 0;
+}
+
 static int bpf_object__collect_externs(struct bpf_object *obj)
 {
+	struct btf_type *sec, *kcfg_sec = NULL, *ksym_sec = NULL;
 	const struct btf_type *t;
 	struct extern_desc *ext;
-	int i, n, off, btf_id;
-	struct btf_type *sec;
-	const char *ext_name;
+	int i, n, off;
+	const char *ext_name, *sec_name;
 	Elf_Scn *scn;
 	GElf_Shdr sh;
 
@@ -2818,22 +2904,50 @@ static int bpf_object__collect_externs(struct bpf_object *obj)
 		ext->name = btf__name_by_offset(obj->btf, t->name_off);
 		ext->sym_idx = i;
 		ext->is_weak = GELF_ST_BIND(sym.st_info) == STB_WEAK;
-		ext->sz = btf__resolve_size(obj->btf, t->type);
-		if (ext->sz <= 0) {
-			pr_warn("failed to resolve size of extern '%s': %d\n",
-				ext_name, ext->sz);
-			return ext->sz;
-		}
-		ext->align = btf__align_of(obj->btf, t->type);
-		if (ext->align <= 0) {
-			pr_warn("failed to determine alignment of extern '%s': %d\n",
-				ext_name, ext->align);
-			return -EINVAL;
-		}
-		ext->type = find_extern_type(obj->btf, t->type,
-					     &ext->is_signed);
-		if (ext->type == EXT_UNKNOWN) {
-			pr_warn("extern '%s' type is unsupported\n", ext_name);
+
+		ext->sec_btf_id = find_extern_sec_btf_id(obj->btf, ext->btf_id);
+		if (ext->sec_btf_id <= 0) {
+			pr_warn("failed to find BTF for extern '%s' [%d] section: %d\n",
+				ext_name, ext->btf_id, ext->sec_btf_id);
+			return ext->sec_btf_id;
+		}
+		sec = (void *)btf__type_by_id(obj->btf, ext->sec_btf_id);
+		sec_name = btf__name_by_offset(obj->btf, sec->name_off);
+
+		if (strcmp(sec_name, KCONFIG_SEC) == 0) {
+			kcfg_sec = sec;
+			ext->type = EXT_KCFG;
+			ext->kcfg.sz = btf__resolve_size(obj->btf, t->type);
+			if (ext->kcfg.sz <= 0) {
+				pr_warn("failed to resolve size of extern (kcfg) '%s': %d\n",
+					ext_name, ext->kcfg.sz);
+				return ext->kcfg.sz;
+			}
+			ext->kcfg.align = btf__align_of(obj->btf, t->type);
+			if (ext->kcfg.align <= 0) {
+				pr_warn("failed to determine alignment of extern (kcfg) '%s': %d\n",
+					ext_name, ext->kcfg.align);
+				return -EINVAL;
+			}
+			ext->kcfg.type = find_kcfg_type(obj->btf, t->type,
+						        &ext->kcfg.is_signed);
+			if (ext->kcfg.type == KCFG_UNKNOWN) {
+				pr_warn("extern (kcfg) '%s' type is unsupported\n", ext_name);
+				return -ENOTSUP;
+			}
+		} else if (strcmp(sec_name, KSYMS_SEC) == 0) {
+			const struct btf_type *vt;
+
+			ksym_sec = sec;
+			ext->type = EXT_KSYM;
+
+			vt = skip_mods_and_typedefs(obj->btf, t->type, NULL);
+			if (!btf_is_void(vt)) {
+				pr_warn("extern (ksym) '%s' is not typeless (void)\n", ext_name);
+				return -ENOTSUP;
+			}
+		} else {
+			pr_warn("unrecognized extern section '%s'\n", sec_name);
 			return -ENOTSUP;
 		}
 	}
@@ -2842,42 +2956,80 @@ static int bpf_object__collect_externs(struct bpf_object *obj)
 	if (!obj->nr_extern)
 		return 0;
 
-	/* sort externs by (alignment, size, name) and calculate their offsets
-	 * within a map */
+	/* sort externs by type, for kcfg ones also by (align, size, name) */
 	qsort(obj->externs, obj->nr_extern, sizeof(*ext), cmp_externs);
-	off = 0;
-	for (i = 0; i < obj->nr_extern; i++) {
-		ext = &obj->externs[i];
-		ext->data_off = roundup(off, ext->align);
-		off = ext->data_off + ext->sz;
-		pr_debug("extern #%d: symbol %d, off %u, name %s\n",
-			 i, ext->sym_idx, ext->data_off, ext->name);
-	}
 
-	btf_id = btf__find_by_name(obj->btf, KCONFIG_SEC);
-	if (btf_id <= 0) {
-		pr_warn("no BTF info found for '%s' datasec\n", KCONFIG_SEC);
-		return -ESRCH;
-	}
+	/* for .ksyms section, we need to turn all externs into allocated
+	 * variables in BTF to pass kernel verification; we do this by
+	 * pretending that each extern is a 8-byte variable
+	 */
+	if (ksym_sec) {
+		/* find existing 4-byte integer type in BTF to use for fake
+		 * extern variables in DATASEC
+		 */
+		int int_btf_id = find_int_btf_id(obj->btf);
 
-	sec = (struct btf_type *)btf__type_by_id(obj->btf, btf_id);
-	sec->size = off;
-	n = btf_vlen(sec);
-	for (i = 0; i < n; i++) {
-		struct btf_var_secinfo *vs = btf_var_secinfos(sec) + i;
-
-		t = btf__type_by_id(obj->btf, vs->type);
-		ext_name = btf__name_by_offset(obj->btf, t->name_off);
-		ext = find_extern_by_name(obj, ext_name);
-		if (!ext) {
-			pr_warn("failed to find extern definition for BTF var '%s'\n",
-				ext_name);
-			return -ESRCH;
+		for (i = 0; i < obj->nr_extern; i++) {
+			ext = &obj->externs[i];
+			if (ext->type != EXT_KSYM)
+				continue;
+			pr_debug("extern (ksym) #%d: symbol %d, name %s\n",
+				 i, ext->sym_idx, ext->name);
 		}
-		vs->offset = ext->data_off;
-		btf_var(t)->linkage = BTF_VAR_GLOBAL_ALLOCATED;
+
+		sec = ksym_sec;
+		n = btf_vlen(sec);
+		for (i = 0, off = 0; i < n; i++, off += sizeof(int)) {
+			struct btf_var_secinfo *vs = btf_var_secinfos(sec) + i;
+			struct btf_type *vt;
+
+			vt = (void *)btf__type_by_id(obj->btf, vs->type);
+			ext_name = btf__name_by_offset(obj->btf, vt->name_off);
+			ext = find_extern_by_name(obj, ext_name);
+			if (!ext) {
+				pr_warn("failed to find extern definition for BTF var '%s'\n",
+					ext_name);
+				return -ESRCH;
+			}
+			btf_var(vt)->linkage = BTF_VAR_GLOBAL_ALLOCATED;
+			vt->type = int_btf_id;
+			vs->offset = off;
+			vs->size = sizeof(int);
+		}
+		sec->size = off;
 	}
 
+	if (kcfg_sec) {
+		sec = kcfg_sec;
+		/* for kcfg externs calculate their offsets within a .kconfig map */
+		off = 0;
+		for (i = 0; i < obj->nr_extern; i++) {
+			ext = &obj->externs[i];
+			if (ext->type != EXT_KCFG)
+				continue;
+
+			ext->kcfg.data_off = roundup(off, ext->kcfg.align);
+			off = ext->kcfg.data_off + ext->kcfg.sz;
+			pr_debug("extern (kcfg) #%d: symbol %d, off %u, name %s\n",
+				 i, ext->sym_idx, ext->kcfg.data_off, ext->name);
+		}
+		sec->size = off;
+		n = btf_vlen(sec);
+		for (i = 0; i < n; i++) {
+			struct btf_var_secinfo *vs = btf_var_secinfos(sec) + i;
+
+			t = btf__type_by_id(obj->btf, vs->type);
+			ext_name = btf__name_by_offset(obj->btf, t->name_off);
+			ext = find_extern_by_name(obj, ext_name);
+			if (!ext) {
+				pr_warn("failed to find extern definition for BTF var '%s'\n",
+					ext_name);
+				return -ESRCH;
+			}
+			btf_var(t)->linkage = BTF_VAR_GLOBAL_ALLOCATED;
+			vs->offset = ext->kcfg.data_off;
+		}
+	}
 	return 0;
 }
 
@@ -3007,11 +3159,11 @@ static int bpf_program__record_reloc(struct bpf_program *prog,
 				sym_idx);
 			return -LIBBPF_ERRNO__RELOC;
 		}
-		pr_debug("found extern #%d '%s' (sym %d, off %u) for insn %u\n",
-			 i, ext->name, ext->sym_idx, ext->data_off, insn_idx);
+		pr_debug("found extern #%d '%s' (sym %d) for insn %u\n",
+			 i, ext->name, ext->sym_idx, insn_idx);
 		reloc_desc->type = RELO_EXTERN;
 		reloc_desc->insn_idx = insn_idx;
-		reloc_desc->sym_off = ext->data_off;
+		reloc_desc->sym_off = i; /* sym_off stores extern index */
 		return 0;
 	}
 
@@ -3222,20 +3374,27 @@ err_free_new_name:
 	return err;
 }
 
-int bpf_map__resize(struct bpf_map *map, __u32 max_entries)
+__u32 bpf_map__max_entries(const struct bpf_map *map)
 {
-	if (!map || !max_entries)
-		return -EINVAL;
+	return map->def.max_entries;
+}
 
-	/* If map already created, its attributes can't be changed. */
+int bpf_map__set_max_entries(struct bpf_map *map, __u32 max_entries)
+{
 	if (map->fd >= 0)
 		return -EBUSY;
-
 	map->def.max_entries = max_entries;
-
 	return 0;
 }
 
+int bpf_map__resize(struct bpf_map *map, __u32 max_entries)
+{
+	if (!map || !max_entries)
+		return -EINVAL;
+
+	return bpf_map__set_max_entries(map, max_entries);
+}
+
 static int
 bpf_object__probe_loading(struct bpf_object *obj)
 {
@@ -3603,6 +3762,7 @@ static int bpf_object__create_map(struct bpf_object *obj, struct bpf_map *map)
 	create_attr.map_flags = def->map_flags;
 	create_attr.key_size = def->key_size;
 	create_attr.value_size = def->value_size;
+	create_attr.numa_node = map->numa_node;
 
 	if (def->type == BPF_MAP_TYPE_PERF_EVENT_ARRAY && !def->max_entries) {
 		int nr_cpus;
@@ -3626,7 +3786,7 @@ static int bpf_object__create_map(struct bpf_object *obj, struct bpf_map *map)
 	create_attr.btf_fd = 0;
 	create_attr.btf_key_type_id = 0;
 	create_attr.btf_value_type_id = 0;
-	if (obj->btf && !bpf_map_find_btf_info(obj, map)) {
+	if (obj->btf && btf__fd(obj->btf) >= 0 && !bpf_map_find_btf_info(obj, map)) {
 		create_attr.btf_fd = btf__fd(obj->btf);
 		create_attr.btf_key_type_id = map->btf_key_type_id;
 		create_attr.btf_value_type_id = map->btf_value_type_id;
@@ -4799,8 +4959,8 @@ bpf_core_reloc_fields(struct bpf_object *obj, const char *targ_btf_path)
 	if (targ_btf_path)
 		targ_btf = btf__parse_elf(targ_btf_path, NULL);
 	else
-		targ_btf = libbpf_find_kernel_btf();
-	if (IS_ERR(targ_btf)) {
+		targ_btf = obj->btf_vmlinux;
+	if (IS_ERR_OR_NULL(targ_btf)) {
 		pr_warn("failed to get target BTF: %ld\n", PTR_ERR(targ_btf));
 		return PTR_ERR(targ_btf);
 	}
@@ -4847,7 +5007,9 @@ bpf_core_reloc_fields(struct bpf_object *obj, const char *targ_btf_path)
 	}
 
 out:
-	btf__free(targ_btf);
+	/* obj->btf_vmlinux is freed at the end of object load phase */
+	if (targ_btf != obj->btf_vmlinux)
+		btf__free(targ_btf);
 	if (!IS_ERR_OR_NULL(cand_cache)) {
 		hashmap__for_each_entry(cand_cache, entry, i) {
 			bpf_core_free_cands(entry->value);
@@ -4934,6 +5096,7 @@ bpf_program__relocate(struct bpf_program *prog, struct bpf_object *obj)
 	for (i = 0; i < prog->nr_reloc; i++) {
 		struct reloc_desc *relo = &prog->reloc_desc[i];
 		struct bpf_insn *insn = &prog->insns[relo->insn_idx];
+		struct extern_desc *ext;
 
 		if (relo->insn_idx + 1 >= (int)prog->insns_cnt) {
 			pr_warn("relocation out of range: '%s'\n",
@@ -4952,9 +5115,15 @@ bpf_program__relocate(struct bpf_program *prog, struct bpf_object *obj)
 			insn[0].imm = obj->maps[relo->map_idx].fd;
 			break;
 		case RELO_EXTERN:
-			insn[0].src_reg = BPF_PSEUDO_MAP_VALUE;
-			insn[0].imm = obj->maps[obj->kconfig_map_idx].fd;
-			insn[1].imm = relo->sym_off;
+			ext = &obj->externs[relo->sym_off];
+			if (ext->type == EXT_KCFG) {
+				insn[0].src_reg = BPF_PSEUDO_MAP_VALUE;
+				insn[0].imm = obj->maps[obj->kconfig_map_idx].fd;
+				insn[1].imm = ext->kcfg.data_off;
+			} else /* EXT_KSYM */ {
+				insn[0].imm = (__u32)ext->ksym.addr;
+				insn[1].imm = ext->ksym.addr >> 32;
+			}
 			break;
 		case RELO_CALL:
 			err = bpf_program__reloc_text(prog, obj, relo);
@@ -5207,18 +5376,17 @@ load_program(struct bpf_program *prog, struct bpf_insn *insns, int insns_cnt,
 		load_attr.kern_version = kern_version;
 		load_attr.prog_ifindex = prog->prog_ifindex;
 	}
-	/* if .BTF.ext was loaded, kernel supports associated BTF for prog */
-	if (prog->obj->btf_ext)
-		btf_fd = bpf_object__btf_fd(prog->obj);
-	else
-		btf_fd = -1;
-	load_attr.prog_btf_fd = btf_fd >= 0 ? btf_fd : 0;
-	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;
-	load_attr.line_info = prog->line_info;
-	load_attr.line_info_rec_size = prog->line_info_rec_size;
-	load_attr.line_info_cnt = prog->line_info_cnt;
+	/* specify func_info/line_info only if kernel supports them */
+	btf_fd = bpf_object__btf_fd(prog->obj);
+	if (btf_fd >= 0 && prog->obj->caps.btf_func) {
+		load_attr.prog_btf_fd = 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;
+		load_attr.line_info = prog->line_info;
+		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;
 	load_attr.prog_flags = prog->prog_flags;
 
@@ -5287,6 +5455,12 @@ int bpf_program__load(struct bpf_program *prog, char *license, __u32 kern_ver)
 {
 	int err = 0, fd, i, btf_id;
 
+	if (prog->obj->loaded) {
+		pr_warn("prog '%s'('%s'): can't load after object was loaded\n",
+			prog->name, prog->section_name);
+		return -EINVAL;
+	}
+
 	if ((prog->type == BPF_PROG_TYPE_TRACING ||
 	     prog->type == BPF_PROG_TYPE_LSM ||
 	     prog->type == BPF_PROG_TYPE_EXT) && !prog->attach_btf_id) {
@@ -5375,16 +5549,21 @@ static bool bpf_program__is_function_storage(const struct bpf_program *prog,
 static int
 bpf_object__load_progs(struct bpf_object *obj, int log_level)
 {
+	struct bpf_program *prog;
 	size_t i;
 	int err;
 
 	for (i = 0; i < obj->nr_programs; i++) {
-		if (bpf_program__is_function_storage(&obj->programs[i], obj))
+		prog = &obj->programs[i];
+		if (bpf_program__is_function_storage(prog, obj))
+			continue;
+		if (!prog->load) {
+			pr_debug("prog '%s'('%s'): skipped loading\n",
+				 prog->name, prog->section_name);
 			continue;
-		obj->programs[i].log_level |= log_level;
-		err = bpf_program__load(&obj->programs[i],
-					obj->license,
-					obj->kern_version);
+		}
+		prog->log_level |= log_level;
+		err = bpf_program__load(prog, obj->license, obj->kern_version);
 		if (err)
 			return err;
 	}
@@ -5573,56 +5752,114 @@ static int bpf_object__sanitize_maps(struct bpf_object *obj)
 	return 0;
 }
 
+static int bpf_object__read_kallsyms_file(struct bpf_object *obj)
+{
+	char sym_type, sym_name[500];
+	unsigned long long sym_addr;
+	struct extern_desc *ext;
+	int ret, err = 0;
+	FILE *f;
+
+	f = fopen("/proc/kallsyms", "r");
+	if (!f) {
+		err = -errno;
+		pr_warn("failed to open /proc/kallsyms: %d\n", err);
+		return err;
+	}
+
+	while (true) {
+		ret = fscanf(f, "%llx %c %499s%*[^\n]\n",
+			     &sym_addr, &sym_type, sym_name);
+		if (ret == EOF && feof(f))
+			break;
+		if (ret != 3) {
+			pr_warn("failed to read kallsyms entry: %d\n", ret);
+			err = -EINVAL;
+			goto out;
+		}
+
+		ext = find_extern_by_name(obj, sym_name);
+		if (!ext || ext->type != EXT_KSYM)
+			continue;
+
+		if (ext->is_set && ext->ksym.addr != sym_addr) {
+			pr_warn("extern (ksym) '%s' resolution is ambiguous: 0x%llx or 0x%llx\n",
+				sym_name, ext->ksym.addr, sym_addr);
+			err = -EINVAL;
+			goto out;
+		}
+		if (!ext->is_set) {
+			ext->is_set = true;
+			ext->ksym.addr = sym_addr;
+			pr_debug("extern (ksym) %s=0x%llx\n", sym_name, sym_addr);
+		}
+	}
+
+out:
+	fclose(f);
+	return err;
+}
+
 static int bpf_object__resolve_externs(struct bpf_object *obj,
 				       const char *extra_kconfig)
 {
-	bool need_config = false;
+	bool need_config = false, need_kallsyms = false;
 	struct extern_desc *ext;
+	void *kcfg_data = NULL;
 	int err, i;
-	void *data;
 
 	if (obj->nr_extern == 0)
 		return 0;
 
-	data = obj->maps[obj->kconfig_map_idx].mmaped;
+	if (obj->kconfig_map_idx >= 0)
+		kcfg_data = obj->maps[obj->kconfig_map_idx].mmaped;
 
 	for (i = 0; i < obj->nr_extern; i++) {
 		ext = &obj->externs[i];
 
-		if (strcmp(ext->name, "LINUX_KERNEL_VERSION") == 0) {
-			void *ext_val = data + ext->data_off;
+		if (ext->type == EXT_KCFG &&
+		    strcmp(ext->name, "LINUX_KERNEL_VERSION") == 0) {
+			void *ext_val = kcfg_data + ext->kcfg.data_off;
 			__u32 kver = get_kernel_version();
 
 			if (!kver) {
 				pr_warn("failed to get kernel version\n");
 				return -EINVAL;
 			}
-			err = set_ext_value_num(ext, ext_val, kver);
+			err = set_kcfg_value_num(ext, ext_val, kver);
 			if (err)
 				return err;
-			pr_debug("extern %s=0x%x\n", ext->name, kver);
-		} else if (strncmp(ext->name, "CONFIG_", 7) == 0) {
+			pr_debug("extern (kcfg) %s=0x%x\n", ext->name, kver);
+		} else if (ext->type == EXT_KCFG &&
+			   strncmp(ext->name, "CONFIG_", 7) == 0) {
 			need_config = true;
+		} else if (ext->type == EXT_KSYM) {
+			need_kallsyms = true;
 		} else {
 			pr_warn("unrecognized extern '%s'\n", ext->name);
 			return -EINVAL;
 		}
 	}
 	if (need_config && extra_kconfig) {
-		err = bpf_object__read_kconfig_mem(obj, extra_kconfig, data);
+		err = bpf_object__read_kconfig_mem(obj, extra_kconfig, kcfg_data);
 		if (err)
 			return -EINVAL;
 		need_config = false;
 		for (i = 0; i < obj->nr_extern; i++) {
 			ext = &obj->externs[i];
-			if (!ext->is_set) {
+			if (ext->type == EXT_KCFG && !ext->is_set) {
 				need_config = true;
 				break;
 			}
 		}
 	}
 	if (need_config) {
-		err = bpf_object__read_kconfig_file(obj, data);
+		err = bpf_object__read_kconfig_file(obj, kcfg_data);
+		if (err)
+			return -EINVAL;
+	}
+	if (need_kallsyms) {
+		err = bpf_object__read_kallsyms_file(obj);
 		if (err)
 			return -EINVAL;
 	}
@@ -5653,12 +5890,10 @@ int bpf_object__load_xattr(struct bpf_object_load_attr *attr)
 		return -EINVAL;
 
 	if (obj->loaded) {
-		pr_warn("object should not be loaded twice\n");
+		pr_warn("object '%s': load can't be attempted twice\n", obj->name);
 		return -EINVAL;
 	}
 
-	obj->loaded = true;
-
 	err = bpf_object__probe_loading(obj);
 	err = err ? : bpf_object__probe_caps(obj);
 	err = err ? : bpf_object__resolve_externs(obj, obj->kconfig);
@@ -5673,6 +5908,8 @@ int bpf_object__load_xattr(struct bpf_object_load_attr *attr)
 	btf__free(obj->btf_vmlinux);
 	obj->btf_vmlinux = NULL;
 
+	obj->loaded = true; /* doesn't matter if successfully or not */
+
 	if (err)
 		goto out;
 
@@ -6267,7 +6504,7 @@ void bpf_object__close(struct bpf_object *obj)
 {
 	size_t i;
 
-	if (!obj)
+	if (IS_ERR_OR_NULL(obj))
 		return;
 
 	if (obj->clear_priv)
@@ -6445,6 +6682,20 @@ const char *bpf_program__title(const struct bpf_program *prog, bool needs_copy)
 	return title;
 }
 
+bool bpf_program__autoload(const struct bpf_program *prog)
+{
+	return prog->load;
+}
+
+int bpf_program__set_autoload(struct bpf_program *prog, bool autoload)
+{
+	if (prog->obj->loaded)
+		return -EINVAL;
+
+	prog->load = autoload;
+	return 0;
+}
+
 int bpf_program__fd(const struct bpf_program *prog)
 {
 	return bpf_program__nth_fd(prog, 0);
@@ -6548,6 +6799,7 @@ BPF_PROG_TYPE_FNS(perf_event, BPF_PROG_TYPE_PERF_EVENT);
 BPF_PROG_TYPE_FNS(tracing, BPF_PROG_TYPE_TRACING);
 BPF_PROG_TYPE_FNS(struct_ops, BPF_PROG_TYPE_STRUCT_OPS);
 BPF_PROG_TYPE_FNS(extension, BPF_PROG_TYPE_EXT);
+BPF_PROG_TYPE_FNS(sk_lookup, BPF_PROG_TYPE_SK_LOOKUP);
 
 enum bpf_attach_type
 bpf_program__get_expected_attach_type(struct bpf_program *prog)
@@ -6661,7 +6913,10 @@ static const struct bpf_sec_def section_defs[] = {
 		.attach_fn = attach_iter),
 	BPF_EAPROG_SEC("xdp_devmap/",		BPF_PROG_TYPE_XDP,
 						BPF_XDP_DEVMAP),
-	BPF_PROG_SEC("xdp",			BPF_PROG_TYPE_XDP),
+	BPF_EAPROG_SEC("xdp_cpumap/",		BPF_PROG_TYPE_XDP,
+						BPF_XDP_CPUMAP),
+	BPF_EAPROG_SEC("xdp",			BPF_PROG_TYPE_XDP,
+						BPF_XDP),
 	BPF_PROG_SEC("perf_event",		BPF_PROG_TYPE_PERF_EVENT),
 	BPF_PROG_SEC("lwt_in",			BPF_PROG_TYPE_LWT_IN),
 	BPF_PROG_SEC("lwt_out",			BPF_PROG_TYPE_LWT_OUT),
@@ -6672,6 +6927,10 @@ static const struct bpf_sec_def section_defs[] = {
 	BPF_APROG_SEC("cgroup_skb/egress",	BPF_PROG_TYPE_CGROUP_SKB,
 						BPF_CGROUP_INET_EGRESS),
 	BPF_APROG_COMPAT("cgroup/skb",		BPF_PROG_TYPE_CGROUP_SKB),
+	BPF_EAPROG_SEC("cgroup/sock_create",	BPF_PROG_TYPE_CGROUP_SOCK,
+						BPF_CGROUP_INET_SOCK_CREATE),
+	BPF_EAPROG_SEC("cgroup/sock_release",	BPF_PROG_TYPE_CGROUP_SOCK,
+						BPF_CGROUP_INET_SOCK_RELEASE),
 	BPF_APROG_SEC("cgroup/sock",		BPF_PROG_TYPE_CGROUP_SOCK,
 						BPF_CGROUP_INET_SOCK_CREATE),
 	BPF_EAPROG_SEC("cgroup/post_bind4",	BPF_PROG_TYPE_CGROUP_SOCK,
@@ -6724,6 +6983,8 @@ static const struct bpf_sec_def section_defs[] = {
 	BPF_EAPROG_SEC("cgroup/setsockopt",	BPF_PROG_TYPE_CGROUP_SOCKOPT,
 						BPF_CGROUP_SETSOCKOPT),
 	BPF_PROG_SEC("struct_ops",		BPF_PROG_TYPE_STRUCT_OPS),
+	BPF_EAPROG_SEC("sk_lookup/",		BPF_PROG_TYPE_SK_LOOKUP,
+						BPF_SK_LOOKUP),
 };
 
 #undef BPF_PROG_SEC_IMPL
@@ -7094,6 +7355,71 @@ const char *bpf_map__name(const struct bpf_map *map)
 	return map ? map->name : NULL;
 }
 
+enum bpf_map_type bpf_map__type(const struct bpf_map *map)
+{
+	return map->def.type;
+}
+
+int bpf_map__set_type(struct bpf_map *map, enum bpf_map_type type)
+{
+	if (map->fd >= 0)
+		return -EBUSY;
+	map->def.type = type;
+	return 0;
+}
+
+__u32 bpf_map__map_flags(const struct bpf_map *map)
+{
+	return map->def.map_flags;
+}
+
+int bpf_map__set_map_flags(struct bpf_map *map, __u32 flags)
+{
+	if (map->fd >= 0)
+		return -EBUSY;
+	map->def.map_flags = flags;
+	return 0;
+}
+
+__u32 bpf_map__numa_node(const struct bpf_map *map)
+{
+	return map->numa_node;
+}
+
+int bpf_map__set_numa_node(struct bpf_map *map, __u32 numa_node)
+{
+	if (map->fd >= 0)
+		return -EBUSY;
+	map->numa_node = numa_node;
+	return 0;
+}
+
+__u32 bpf_map__key_size(const struct bpf_map *map)
+{
+	return map->def.key_size;
+}
+
+int bpf_map__set_key_size(struct bpf_map *map, __u32 size)
+{
+	if (map->fd >= 0)
+		return -EBUSY;
+	map->def.key_size = size;
+	return 0;
+}
+
+__u32 bpf_map__value_size(const struct bpf_map *map)
+{
+	return map->def.value_size;
+}
+
+int bpf_map__set_value_size(struct bpf_map *map, __u32 size)
+{
+	if (map->fd >= 0)
+		return -EBUSY;
+	map->def.value_size = size;
+	return 0;
+}
+
 __u32 bpf_map__btf_key_type_id(const struct bpf_map *map)
 {
 	return map ? map->btf_key_type_id : 0;
@@ -7146,9 +7472,17 @@ bool bpf_map__is_internal(const struct bpf_map *map)
 	return map->libbpf_type != LIBBPF_MAP_UNSPEC;
 }
 
-void bpf_map__set_ifindex(struct bpf_map *map, __u32 ifindex)
+__u32 bpf_map__ifindex(const struct bpf_map *map)
+{
+	return map->map_ifindex;
+}
+
+int bpf_map__set_ifindex(struct bpf_map *map, __u32 ifindex)
 {
+	if (map->fd >= 0)
+		return -EBUSY;
 	map->map_ifindex = ifindex;
+	return 0;
 }
 
 int bpf_map__set_inner_map_fd(struct bpf_map *map, int fd)
@@ -7356,7 +7690,7 @@ int bpf_link__destroy(struct bpf_link *link)
 {
 	int err = 0;
 
-	if (!link)
+	if (IS_ERR_OR_NULL(link))
 		return 0;
 
 	if (!link->disconnected && link->detach)
@@ -7414,6 +7748,11 @@ struct bpf_link *bpf_link__open(const char *path)
 	return link;
 }
 
+int bpf_link__detach(struct bpf_link *link)
+{
+	return bpf_link_detach(link->fd) ? -errno : 0;
+}
+
 int bpf_link__pin(struct bpf_link *link, const char *path)
 {
 	int err;
@@ -7500,6 +7839,9 @@ struct bpf_link *bpf_program__attach_perf_event(struct bpf_program *prog,
 		pr_warn("program '%s': failed to attach to pfd %d: %s\n",
 			bpf_program__title(prog, false), pfd,
 			   libbpf_strerror_r(err, errmsg, sizeof(errmsg)));
+		if (err == -EPROTO)
+			pr_warn("program '%s': try add PERF_SAMPLE_CALLCHAIN to or remove exclude_callchain_[kernel|user] from pfd %d\n",
+				bpf_program__title(prog, false), pfd);
 		return ERR_PTR(err);
 	}
 	if (ioctl(pfd, PERF_EVENT_IOC_ENABLE, 0) < 0) {
@@ -7945,17 +8287,30 @@ bpf_program__attach_netns(struct bpf_program *prog, int netns_fd)
 	return bpf_program__attach_fd(prog, netns_fd, "netns");
 }
 
+struct bpf_link *bpf_program__attach_xdp(struct bpf_program *prog, int ifindex)
+{
+	/* target_fd/target_ifindex use the same field in LINK_CREATE */
+	return bpf_program__attach_fd(prog, ifindex, "xdp");
+}
+
 struct bpf_link *
 bpf_program__attach_iter(struct bpf_program *prog,
 			 const struct bpf_iter_attach_opts *opts)
 {
+	DECLARE_LIBBPF_OPTS(bpf_link_create_opts, link_create_opts);
 	char errmsg[STRERR_BUFSIZE];
 	struct bpf_link *link;
 	int prog_fd, link_fd;
+	__u32 target_fd = 0;
 
 	if (!OPTS_VALID(opts, bpf_iter_attach_opts))
 		return ERR_PTR(-EINVAL);
 
+	if (OPTS_HAS(opts, map_fd)) {
+		target_fd = opts->map_fd;
+		link_create_opts.flags = BPF_ITER_LINK_MAP_FD;
+	}
+
 	prog_fd = bpf_program__fd(prog);
 	if (prog_fd < 0) {
 		pr_warn("program '%s': can't attach before loaded\n",
@@ -7968,7 +8323,8 @@ bpf_program__attach_iter(struct bpf_program *prog,
 		return ERR_PTR(-ENOMEM);
 	link->detach = &bpf_link__detach_fd;
 
-	link_fd = bpf_link_create(prog_fd, 0, BPF_TRACE_ITER, NULL);
+	link_fd = bpf_link_create(prog_fd, target_fd, BPF_TRACE_ITER,
+				  &link_create_opts);
 	if (link_fd < 0) {
 		link_fd = -errno;
 		free(link);
@@ -8151,7 +8507,7 @@ void perf_buffer__free(struct perf_buffer *pb)
 {
 	int i;
 
-	if (!pb)
+	if (IS_ERR_OR_NULL(pb))
 		return;
 	if (pb->cpu_bufs) {
 		for (i = 0; i < pb->cpu_cnt; i++) {
@@ -8264,7 +8620,7 @@ static struct perf_buffer *__perf_buffer__new(int map_fd, size_t page_cnt,
 					      struct perf_buffer_params *p)
 {
 	const char *online_cpus_file = "/sys/devices/system/cpu/online";
-	struct bpf_map_info map = {};
+	struct bpf_map_info map;
 	char msg[STRERR_BUFSIZE];
 	struct perf_buffer *pb;
 	bool *online = NULL;
@@ -8277,19 +8633,28 @@ static struct perf_buffer *__perf_buffer__new(int map_fd, size_t page_cnt,
 		return ERR_PTR(-EINVAL);
 	}
 
+	/* best-effort sanity checks */
+	memset(&map, 0, sizeof(map));
 	map_info_len = sizeof(map);
 	err = bpf_obj_get_info_by_fd(map_fd, &map, &map_info_len);
 	if (err) {
 		err = -errno;
-		pr_warn("failed to get map info for map FD %d: %s\n",
-			map_fd, libbpf_strerror_r(err, msg, sizeof(msg)));
-		return ERR_PTR(err);
-	}
-
-	if (map.type != BPF_MAP_TYPE_PERF_EVENT_ARRAY) {
-		pr_warn("map '%s' should be BPF_MAP_TYPE_PERF_EVENT_ARRAY\n",
-			map.name);
-		return ERR_PTR(-EINVAL);
+		/* if BPF_OBJ_GET_INFO_BY_FD is supported, will return
+		 * -EBADFD, -EFAULT, or -E2BIG on real error
+		 */
+		if (err != -EINVAL) {
+			pr_warn("failed to get map info for map FD %d: %s\n",
+				map_fd, libbpf_strerror_r(err, msg, sizeof(msg)));
+			return ERR_PTR(err);
+		}
+		pr_debug("failed to get map info for FD %d; API not supported? Ignoring...\n",
+			 map_fd);
+	} else {
+		if (map.type != BPF_MAP_TYPE_PERF_EVENT_ARRAY) {
+			pr_warn("map '%s' should be BPF_MAP_TYPE_PERF_EVENT_ARRAY\n",
+				map.name);
+			return ERR_PTR(-EINVAL);
+		}
 	}
 
 	pb = calloc(1, sizeof(*pb));
@@ -8321,7 +8686,7 @@ static struct perf_buffer *__perf_buffer__new(int map_fd, size_t page_cnt,
 			err = pb->cpu_cnt;
 			goto error;
 		}
-		if (map.max_entries < pb->cpu_cnt)
+		if (map.max_entries && map.max_entries < pb->cpu_cnt)
 			pb->cpu_cnt = map.max_entries;
 	}
 
@@ -8994,6 +9359,9 @@ int bpf_object__attach_skeleton(struct bpf_object_skeleton *s)
 		const struct bpf_sec_def *sec_def;
 		const char *sec_name = bpf_program__title(prog, false);
 
+		if (!prog->load)
+			continue;
+
 		sec_def = find_sec_def(sec_name);
 		if (!sec_def || !sec_def->attach_fn)
 			continue;
@@ -9016,8 +9384,7 @@ void bpf_object__detach_skeleton(struct bpf_object_skeleton *s)
 	for (i = 0; i < s->prog_cnt; i++) {
 		struct bpf_link **link = s->progs[i].link;
 
-		if (!IS_ERR_OR_NULL(*link))
-			bpf_link__destroy(*link);
+		bpf_link__destroy(*link);
 		*link = NULL;
 	}
 }
diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h
index 334437af3014..3ed1399bfbbc 100644
--- a/tools/lib/bpf/libbpf.h
+++ b/tools/lib/bpf/libbpf.h
@@ -200,6 +200,8 @@ LIBBPF_API void bpf_program__set_ifindex(struct bpf_program *prog,
 LIBBPF_API const char *bpf_program__name(const struct bpf_program *prog);
 LIBBPF_API const char *bpf_program__title(const struct bpf_program *prog,
 					  bool needs_copy);
+LIBBPF_API bool bpf_program__autoload(const struct bpf_program *prog);
+LIBBPF_API int bpf_program__set_autoload(struct bpf_program *prog, bool autoload);
 
 /* returns program size in bytes */
 LIBBPF_API size_t bpf_program__size(const struct bpf_program *prog);
@@ -227,6 +229,7 @@ LIBBPF_API int bpf_link__unpin(struct bpf_link *link);
 LIBBPF_API int bpf_link__update_program(struct bpf_link *link,
 					struct bpf_program *prog);
 LIBBPF_API void bpf_link__disconnect(struct bpf_link *link);
+LIBBPF_API int bpf_link__detach(struct bpf_link *link);
 LIBBPF_API int bpf_link__destroy(struct bpf_link *link);
 
 LIBBPF_API struct bpf_link *
@@ -255,6 +258,8 @@ LIBBPF_API struct bpf_link *
 bpf_program__attach_cgroup(struct bpf_program *prog, int cgroup_fd);
 LIBBPF_API struct bpf_link *
 bpf_program__attach_netns(struct bpf_program *prog, int netns_fd);
+LIBBPF_API struct bpf_link *
+bpf_program__attach_xdp(struct bpf_program *prog, int ifindex);
 
 struct bpf_map;
 
@@ -262,8 +267,9 @@ LIBBPF_API struct bpf_link *bpf_map__attach_struct_ops(struct bpf_map *map);
 
 struct bpf_iter_attach_opts {
 	size_t sz; /* size of this struct for forward/backward compatibility */
+	__u32 map_fd;
 };
-#define bpf_iter_attach_opts__last_field sz
+#define bpf_iter_attach_opts__last_field map_fd
 
 LIBBPF_API struct bpf_link *
 bpf_program__attach_iter(struct bpf_program *prog,
@@ -348,6 +354,7 @@ LIBBPF_API int bpf_program__set_perf_event(struct bpf_program *prog);
 LIBBPF_API int bpf_program__set_tracing(struct bpf_program *prog);
 LIBBPF_API int bpf_program__set_struct_ops(struct bpf_program *prog);
 LIBBPF_API int bpf_program__set_extension(struct bpf_program *prog);
+LIBBPF_API int bpf_program__set_sk_lookup(struct bpf_program *prog);
 
 LIBBPF_API enum bpf_prog_type bpf_program__get_type(struct bpf_program *prog);
 LIBBPF_API void bpf_program__set_type(struct bpf_program *prog,
@@ -375,6 +382,7 @@ LIBBPF_API bool bpf_program__is_perf_event(const struct bpf_program *prog);
 LIBBPF_API bool bpf_program__is_tracing(const struct bpf_program *prog);
 LIBBPF_API bool bpf_program__is_struct_ops(const struct bpf_program *prog);
 LIBBPF_API bool bpf_program__is_extension(const struct bpf_program *prog);
+LIBBPF_API bool bpf_program__is_sk_lookup(const struct bpf_program *prog);
 
 /*
  * No need for __attribute__((packed)), all members of 'bpf_map_def'
@@ -418,11 +426,38 @@ bpf_map__next(const struct bpf_map *map, const struct bpf_object *obj);
 LIBBPF_API struct bpf_map *
 bpf_map__prev(const struct bpf_map *map, const struct bpf_object *obj);
 
+/* get/set map FD */
 LIBBPF_API int bpf_map__fd(const struct bpf_map *map);
+LIBBPF_API int bpf_map__reuse_fd(struct bpf_map *map, int fd);
+/* get map definition */
 LIBBPF_API const struct bpf_map_def *bpf_map__def(const struct bpf_map *map);
+/* get map name */
 LIBBPF_API const char *bpf_map__name(const struct bpf_map *map);
+/* get/set map type */
+LIBBPF_API enum bpf_map_type bpf_map__type(const struct bpf_map *map);
+LIBBPF_API int bpf_map__set_type(struct bpf_map *map, enum bpf_map_type type);
+/* get/set map size (max_entries) */
+LIBBPF_API __u32 bpf_map__max_entries(const struct bpf_map *map);
+LIBBPF_API int bpf_map__set_max_entries(struct bpf_map *map, __u32 max_entries);
+LIBBPF_API int bpf_map__resize(struct bpf_map *map, __u32 max_entries);
+/* get/set map flags */
+LIBBPF_API __u32 bpf_map__map_flags(const struct bpf_map *map);
+LIBBPF_API int bpf_map__set_map_flags(struct bpf_map *map, __u32 flags);
+/* get/set map NUMA node */
+LIBBPF_API __u32 bpf_map__numa_node(const struct bpf_map *map);
+LIBBPF_API int bpf_map__set_numa_node(struct bpf_map *map, __u32 numa_node);
+/* get/set map key size */
+LIBBPF_API __u32 bpf_map__key_size(const struct bpf_map *map);
+LIBBPF_API int bpf_map__set_key_size(struct bpf_map *map, __u32 size);
+/* get/set map value size */
+LIBBPF_API __u32 bpf_map__value_size(const struct bpf_map *map);
+LIBBPF_API int bpf_map__set_value_size(struct bpf_map *map, __u32 size);
+/* get map key/value BTF type IDs */
 LIBBPF_API __u32 bpf_map__btf_key_type_id(const struct bpf_map *map);
 LIBBPF_API __u32 bpf_map__btf_value_type_id(const struct bpf_map *map);
+/* get/set map if_index */
+LIBBPF_API __u32 bpf_map__ifindex(const struct bpf_map *map);
+LIBBPF_API int bpf_map__set_ifindex(struct bpf_map *map, __u32 ifindex);
 
 typedef void (*bpf_map_clear_priv_t)(struct bpf_map *, void *);
 LIBBPF_API int bpf_map__set_priv(struct bpf_map *map, void *priv,
@@ -430,11 +465,8 @@ LIBBPF_API int bpf_map__set_priv(struct bpf_map *map, void *priv,
 LIBBPF_API void *bpf_map__priv(const struct bpf_map *map);
 LIBBPF_API int bpf_map__set_initial_value(struct bpf_map *map,
 					  const void *data, size_t size);
-LIBBPF_API int bpf_map__reuse_fd(struct bpf_map *map, int fd);
-LIBBPF_API int bpf_map__resize(struct bpf_map *map, __u32 max_entries);
 LIBBPF_API bool bpf_map__is_offload_neutral(const struct bpf_map *map);
 LIBBPF_API bool bpf_map__is_internal(const struct bpf_map *map);
-LIBBPF_API void bpf_map__set_ifindex(struct bpf_map *map, __u32 ifindex);
 LIBBPF_API int bpf_map__set_pin_path(struct bpf_map *map, const char *path);
 LIBBPF_API const char *bpf_map__get_pin_path(const struct bpf_map *map);
 LIBBPF_API bool bpf_map__is_pinned(const struct bpf_map *map);
diff --git a/tools/lib/bpf/libbpf.map b/tools/lib/bpf/libbpf.map
index f732c77b7ed0..0c4722bfdd0a 100644
--- a/tools/lib/bpf/libbpf.map
+++ b/tools/lib/bpf/libbpf.map
@@ -270,3 +270,30 @@ LIBBPF_0.0.9 {
 		ring_buffer__new;
 		ring_buffer__poll;
 } LIBBPF_0.0.8;
+
+LIBBPF_0.1.0 {
+	global:
+		bpf_link__detach;
+		bpf_link_detach;
+		bpf_map__ifindex;
+		bpf_map__key_size;
+		bpf_map__map_flags;
+		bpf_map__max_entries;
+		bpf_map__numa_node;
+		bpf_map__set_key_size;
+		bpf_map__set_map_flags;
+		bpf_map__set_max_entries;
+		bpf_map__set_numa_node;
+		bpf_map__set_type;
+		bpf_map__set_value_size;
+		bpf_map__type;
+		bpf_map__value_size;
+		bpf_program__attach_xdp;
+		bpf_program__autoload;
+		bpf_program__is_sk_lookup;
+		bpf_program__set_autoload;
+		bpf_program__set_sk_lookup;
+		btf__parse;
+		btf__parse_raw;
+		btf__set_fd;
+} LIBBPF_0.0.9;
diff --git a/tools/lib/bpf/libbpf_probes.c b/tools/lib/bpf/libbpf_probes.c
index 10cd8d1891f5..5a3d3f078408 100644
--- a/tools/lib/bpf/libbpf_probes.c
+++ b/tools/lib/bpf/libbpf_probes.c
@@ -78,6 +78,9 @@ probe_load(enum bpf_prog_type prog_type, const struct bpf_insn *insns,
 	case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
 		xattr.expected_attach_type = BPF_CGROUP_INET4_CONNECT;
 		break;
+	case BPF_PROG_TYPE_SK_LOOKUP:
+		xattr.expected_attach_type = BPF_SK_LOOKUP;
+		break;
 	case BPF_PROG_TYPE_KPROBE:
 		xattr.kern_version = get_kernel_version();
 		break;