Revert BPF token-related functionality

This patch includes the following revert (one  conflicting BPF FS
patch and three token patch sets, represented by merge commits):
  - revert 0f5d5454c723 "Merge branch 'bpf-fs-mount-options-parsing-follow-ups'";
  - revert 750e785796bb "bpf: Support uid and gid when mounting bpffs";
  - revert 733763285acf "Merge branch 'bpf-token-support-in-libbpf-s-bpf-object'";
  - revert c35919dcce28 "Merge branch 'bpf-token-and-bpf-fs-based-delegation'".

Link: https://lore.kernel.org/bpf/CAHk-=wg7JuFYwGy=GOMbRCtOL+jwSQsdUaBsRWkDVYbxipbM5A@mail.gmail.com
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>

12 files changed, 478 insertions, 741 deletions

diff --git a/tools/lib/bpf/Build b/tools/lib/bpf/Build
index b6619199a706..2d0c282c8588 100644
--- a/tools/lib/bpf/Build
+++ b/tools/lib/bpf/Build
@@ -1,4 +1,4 @@
 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 hashmap.o \
 	    btf_dump.o ringbuf.o strset.o linker.o gen_loader.o relo_core.o \
-	    usdt.o zip.o elf.o features.o
+	    usdt.o zip.o elf.o
diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c
index 0ad8e532b3cf..9dc9625651dc 100644
--- a/tools/lib/bpf/bpf.c
+++ b/tools/lib/bpf/bpf.c
@@ -103,7 +103,7 @@ int sys_bpf_prog_load(union bpf_attr *attr, unsigned int size, int attempts)
  *   [0] https://lore.kernel.org/bpf/20201201215900.3569844-1-guro@fb.com/
  *   [1] d05512618056 ("bpf: Add bpf_ktime_get_coarse_ns helper")
  */
-int probe_memcg_account(int token_fd)
+int probe_memcg_account(void)
 {
 	const size_t attr_sz = offsetofend(union bpf_attr, attach_btf_obj_fd);
 	struct bpf_insn insns[] = {
@@ -120,7 +120,6 @@ int probe_memcg_account(int token_fd)
 	attr.insns = ptr_to_u64(insns);
 	attr.insn_cnt = insn_cnt;
 	attr.license = ptr_to_u64("GPL");
-	attr.prog_token_fd = token_fd;
 
 	prog_fd = sys_bpf_fd(BPF_PROG_LOAD, &attr, attr_sz);
 	if (prog_fd >= 0) {
@@ -147,7 +146,7 @@ int bump_rlimit_memlock(void)
 	struct rlimit rlim;
 
 	/* if kernel supports memcg-based accounting, skip bumping RLIMIT_MEMLOCK */
-	if (memlock_bumped || feat_supported(NULL, FEAT_MEMCG_ACCOUNT))
+	if (memlock_bumped || kernel_supports(NULL, FEAT_MEMCG_ACCOUNT))
 		return 0;
 
 	memlock_bumped = true;
@@ -170,7 +169,7 @@ int bpf_map_create(enum bpf_map_type map_type,
 		   __u32 max_entries,
 		   const struct bpf_map_create_opts *opts)
 {
-	const size_t attr_sz = offsetofend(union bpf_attr, map_token_fd);
+	const size_t attr_sz = offsetofend(union bpf_attr, map_extra);
 	union bpf_attr attr;
 	int fd;
 
@@ -182,7 +181,7 @@ int bpf_map_create(enum bpf_map_type map_type,
 		return libbpf_err(-EINVAL);
 
 	attr.map_type = map_type;
-	if (map_name && feat_supported(NULL, FEAT_PROG_NAME))
+	if (map_name && kernel_supports(NULL, FEAT_PROG_NAME))
 		libbpf_strlcpy(attr.map_name, map_name, sizeof(attr.map_name));
 	attr.key_size = key_size;
 	attr.value_size = value_size;
@@ -199,8 +198,6 @@ int bpf_map_create(enum bpf_map_type map_type,
 	attr.numa_node = OPTS_GET(opts, numa_node, 0);
 	attr.map_ifindex = OPTS_GET(opts, map_ifindex, 0);
 
-	attr.map_token_fd = OPTS_GET(opts, token_fd, 0);
-
 	fd = sys_bpf_fd(BPF_MAP_CREATE, &attr, attr_sz);
 	return libbpf_err_errno(fd);
 }
@@ -235,7 +232,7 @@ int bpf_prog_load(enum bpf_prog_type prog_type,
 		  const struct bpf_insn *insns, size_t insn_cnt,
 		  struct bpf_prog_load_opts *opts)
 {
-	const size_t attr_sz = offsetofend(union bpf_attr, prog_token_fd);
+	const size_t attr_sz = offsetofend(union bpf_attr, log_true_size);
 	void *finfo = NULL, *linfo = NULL;
 	const char *func_info, *line_info;
 	__u32 log_size, log_level, attach_prog_fd, attach_btf_obj_fd;
@@ -264,9 +261,8 @@ int bpf_prog_load(enum bpf_prog_type prog_type,
 	attr.prog_flags = OPTS_GET(opts, prog_flags, 0);
 	attr.prog_ifindex = OPTS_GET(opts, prog_ifindex, 0);
 	attr.kern_version = OPTS_GET(opts, kern_version, 0);
-	attr.prog_token_fd = OPTS_GET(opts, token_fd, 0);
 
-	if (prog_name && feat_supported(NULL, FEAT_PROG_NAME))
+	if (prog_name && kernel_supports(NULL, FEAT_PROG_NAME))
 		libbpf_strlcpy(attr.prog_name, prog_name, sizeof(attr.prog_name));
 	attr.license = ptr_to_u64(license);
 
@@ -1186,7 +1182,7 @@ int bpf_raw_tracepoint_open(const char *name, int prog_fd)
 
 int bpf_btf_load(const void *btf_data, size_t btf_size, struct bpf_btf_load_opts *opts)
 {
-	const size_t attr_sz = offsetofend(union bpf_attr, btf_token_fd);
+	const size_t attr_sz = offsetofend(union bpf_attr, btf_log_true_size);
 	union bpf_attr attr;
 	char *log_buf;
 	size_t log_size;
@@ -1211,8 +1207,6 @@ int bpf_btf_load(const void *btf_data, size_t btf_size, struct bpf_btf_load_opts
 
 	attr.btf = ptr_to_u64(btf_data);
 	attr.btf_size = btf_size;
-	attr.btf_token_fd = OPTS_GET(opts, token_fd, 0);
-
 	/* log_level == 0 and log_buf != NULL means "try loading without
 	 * log_buf, but retry with log_buf and log_level=1 on error", which is
 	 * consistent across low-level and high-level BTF and program loading
@@ -1293,20 +1287,3 @@ int bpf_prog_bind_map(int prog_fd, int map_fd,
 	ret = sys_bpf(BPF_PROG_BIND_MAP, &attr, attr_sz);
 	return libbpf_err_errno(ret);
 }
-
-int bpf_token_create(int bpffs_fd, struct bpf_token_create_opts *opts)
-{
-	const size_t attr_sz = offsetofend(union bpf_attr, token_create);
-	union bpf_attr attr;
-	int fd;
-
-	if (!OPTS_VALID(opts, bpf_token_create_opts))
-		return libbpf_err(-EINVAL);
-
-	memset(&attr, 0, attr_sz);
-	attr.token_create.bpffs_fd = bpffs_fd;
-	attr.token_create.flags = OPTS_GET(opts, flags, 0);
-
-	fd = sys_bpf_fd(BPF_TOKEN_CREATE, &attr, attr_sz);
-	return libbpf_err_errno(fd);
-}
diff --git a/tools/lib/bpf/bpf.h b/tools/lib/bpf/bpf.h
index 991b86bfe7e4..d0f53772bdc0 100644
--- a/tools/lib/bpf/bpf.h
+++ b/tools/lib/bpf/bpf.h
@@ -51,11 +51,8 @@ struct bpf_map_create_opts {
 
 	__u32 numa_node;
 	__u32 map_ifindex;
-
-	__u32 token_fd;
-	size_t :0;
 };
-#define bpf_map_create_opts__last_field token_fd
+#define bpf_map_create_opts__last_field map_ifindex
 
 LIBBPF_API int bpf_map_create(enum bpf_map_type map_type,
 			      const char *map_name,
@@ -105,10 +102,9 @@ struct bpf_prog_load_opts {
 	 * If kernel doesn't support this feature, log_size is left unchanged.
 	 */
 	__u32 log_true_size;
-	__u32 token_fd;
 	size_t :0;
 };
-#define bpf_prog_load_opts__last_field token_fd
+#define bpf_prog_load_opts__last_field log_true_size
 
 LIBBPF_API int bpf_prog_load(enum bpf_prog_type prog_type,
 			     const char *prog_name, const char *license,
@@ -134,10 +130,9 @@ struct bpf_btf_load_opts {
 	 * If kernel doesn't support this feature, log_size is left unchanged.
 	 */
 	__u32 log_true_size;
-	__u32 token_fd;
 	size_t :0;
 };
-#define bpf_btf_load_opts__last_field token_fd
+#define bpf_btf_load_opts__last_field log_true_size
 
 LIBBPF_API int bpf_btf_load(const void *btf_data, size_t btf_size,
 			    struct bpf_btf_load_opts *opts);
@@ -645,30 +640,6 @@ struct bpf_test_run_opts {
 LIBBPF_API int bpf_prog_test_run_opts(int prog_fd,
 				      struct bpf_test_run_opts *opts);
 
-struct bpf_token_create_opts {
-	size_t sz; /* size of this struct for forward/backward compatibility */
-	__u32 flags;
-	size_t :0;
-};
-#define bpf_token_create_opts__last_field flags
-
-/**
- * @brief **bpf_token_create()** creates a new instance of BPF token derived
- * from specified BPF FS mount point.
- *
- * BPF token created with this API can be passed to bpf() syscall for
- * commands like BPF_PROG_LOAD, BPF_MAP_CREATE, etc.
- *
- * @param bpffs_fd FD for BPF FS instance from which to derive a BPF token
- * instance.
- * @param opts optional BPF token creation options, can be NULL
- *
- * @return BPF token FD > 0, on success; negative error code, otherwise (errno
- * is also set to the error code)
- */
-LIBBPF_API int bpf_token_create(int bpffs_fd,
-				struct bpf_token_create_opts *opts);
-
 #ifdef __cplusplus
 } /* extern "C" */
 #endif
diff --git a/tools/lib/bpf/btf.c b/tools/lib/bpf/btf.c
index 63033c334320..ee95fd379d4d 100644
--- a/tools/lib/bpf/btf.c
+++ b/tools/lib/bpf/btf.c
@@ -1317,9 +1317,7 @@ struct btf *btf__parse_split(const char *path, struct btf *base_btf)
 
 static void *btf_get_raw_data(const struct btf *btf, __u32 *size, bool swap_endian);
 
-int btf_load_into_kernel(struct btf *btf,
-			 char *log_buf, size_t log_sz, __u32 log_level,
-			 int token_fd)
+int btf_load_into_kernel(struct btf *btf, char *log_buf, size_t log_sz, __u32 log_level)
 {
 	LIBBPF_OPTS(bpf_btf_load_opts, opts);
 	__u32 buf_sz = 0, raw_size;
@@ -1369,7 +1367,6 @@ retry_load:
 		opts.log_level = log_level;
 	}
 
-	opts.token_fd = token_fd;
 	btf->fd = bpf_btf_load(raw_data, raw_size, &opts);
 	if (btf->fd < 0) {
 		/* time to turn on verbose mode and try again */
@@ -1397,7 +1394,7 @@ done:
 
 int btf__load_into_kernel(struct btf *btf)
 {
-	return btf_load_into_kernel(btf, NULL, 0, 0, 0);
+	return btf_load_into_kernel(btf, NULL, 0, 0);
 }
 
 int btf__fd(const struct btf *btf)
diff --git a/tools/lib/bpf/elf.c b/tools/lib/bpf/elf.c
index c92e02394159..b02faec748a5 100644
--- a/tools/lib/bpf/elf.c
+++ b/tools/lib/bpf/elf.c
@@ -11,6 +11,8 @@
 #include "libbpf_internal.h"
 #include "str_error.h"
 
+#define STRERR_BUFSIZE  128
+
 /* A SHT_GNU_versym section holds 16-bit words. This bit is set if
  * the symbol is hidden and can only be seen when referenced using an
  * explicit version number. This is a GNU extension.
diff --git a/tools/lib/bpf/features.c b/tools/lib/bpf/features.c
deleted file mode 100644
index ce98a334be21..000000000000
--- a/tools/lib/bpf/features.c
+++ /dev/null
@@ -1,478 +0,0 @@
-// SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
-/* Copyright (c) 2023 Meta Platforms, Inc. and affiliates. */
-#include <linux/kernel.h>
-#include <linux/filter.h>
-#include "bpf.h"
-#include "libbpf.h"
-#include "libbpf_common.h"
-#include "libbpf_internal.h"
-#include "str_error.h"
-
-static inline __u64 ptr_to_u64(const void *ptr)
-{
-	return (__u64)(unsigned long)ptr;
-}
-
-static int probe_fd(int fd)
-{
-	if (fd >= 0)
-		close(fd);
-	return fd >= 0;
-}
-
-static int probe_kern_prog_name(int token_fd)
-{
-	const size_t attr_sz = offsetofend(union bpf_attr, prog_name);
-	struct bpf_insn insns[] = {
-		BPF_MOV64_IMM(BPF_REG_0, 0),
-		BPF_EXIT_INSN(),
-	};
-	union bpf_attr attr;
-	int ret;
-
-	memset(&attr, 0, attr_sz);
-	attr.prog_type = BPF_PROG_TYPE_SOCKET_FILTER;
-	attr.license = ptr_to_u64("GPL");
-	attr.insns = ptr_to_u64(insns);
-	attr.insn_cnt = (__u32)ARRAY_SIZE(insns);
-	attr.prog_token_fd = token_fd;
-	libbpf_strlcpy(attr.prog_name, "libbpf_nametest", sizeof(attr.prog_name));
-
-	/* make sure loading with name works */
-	ret = sys_bpf_prog_load(&attr, attr_sz, PROG_LOAD_ATTEMPTS);
-	return probe_fd(ret);
-}
-
-static int probe_kern_global_data(int token_fd)
-{
-	char *cp, errmsg[STRERR_BUFSIZE];
-	struct bpf_insn insns[] = {
-		BPF_LD_MAP_VALUE(BPF_REG_1, 0, 16),
-		BPF_ST_MEM(BPF_DW, BPF_REG_1, 0, 42),
-		BPF_MOV64_IMM(BPF_REG_0, 0),
-		BPF_EXIT_INSN(),
-	};
-	LIBBPF_OPTS(bpf_map_create_opts, map_opts, .token_fd = token_fd);
-	LIBBPF_OPTS(bpf_prog_load_opts, prog_opts, .token_fd = token_fd);
-	int ret, map, insn_cnt = ARRAY_SIZE(insns);
-
-	map = bpf_map_create(BPF_MAP_TYPE_ARRAY, "libbpf_global", sizeof(int), 32, 1, &map_opts);
-	if (map < 0) {
-		ret = -errno;
-		cp = libbpf_strerror_r(ret, errmsg, sizeof(errmsg));
-		pr_warn("Error in %s():%s(%d). Couldn't create simple array map.\n",
-			__func__, cp, -ret);
-		return ret;
-	}
-
-	insns[0].imm = map;
-
-	ret = bpf_prog_load(BPF_PROG_TYPE_SOCKET_FILTER, NULL, "GPL", insns, insn_cnt, &prog_opts);
-	close(map);
-	return probe_fd(ret);
-}
-
-static int probe_kern_btf(int token_fd)
-{
-	static const char strs[] = "\0int";
-	__u32 types[] = {
-		/* int */
-		BTF_TYPE_INT_ENC(1, BTF_INT_SIGNED, 0, 32, 4),
-	};
-
-	return probe_fd(libbpf__load_raw_btf((char *)types, sizeof(types),
-					     strs, sizeof(strs), token_fd));
-}
-
-static int probe_kern_btf_func(int token_fd)
-{
-	static const char strs[] = "\0int\0x\0a";
-	/* void x(int a) {} */
-	__u32 types[] = {
-		/* int */
-		BTF_TYPE_INT_ENC(1, BTF_INT_SIGNED, 0, 32, 4),  /* [1] */
-		/* FUNC_PROTO */                                /* [2] */
-		BTF_TYPE_ENC(0, BTF_INFO_ENC(BTF_KIND_FUNC_PROTO, 0, 1), 0),
-		BTF_PARAM_ENC(7, 1),
-		/* FUNC x */                                    /* [3] */
-		BTF_TYPE_ENC(5, BTF_INFO_ENC(BTF_KIND_FUNC, 0, 0), 2),
-	};
-
-	return probe_fd(libbpf__load_raw_btf((char *)types, sizeof(types),
-					     strs, sizeof(strs), token_fd));
-}
-
-static int probe_kern_btf_func_global(int token_fd)
-{
-	static const char strs[] = "\0int\0x\0a";
-	/* static void x(int a) {} */
-	__u32 types[] = {
-		/* int */
-		BTF_TYPE_INT_ENC(1, BTF_INT_SIGNED, 0, 32, 4),  /* [1] */
-		/* FUNC_PROTO */                                /* [2] */
-		BTF_TYPE_ENC(0, BTF_INFO_ENC(BTF_KIND_FUNC_PROTO, 0, 1), 0),
-		BTF_PARAM_ENC(7, 1),
-		/* FUNC x BTF_FUNC_GLOBAL */                    /* [3] */
-		BTF_TYPE_ENC(5, BTF_INFO_ENC(BTF_KIND_FUNC, 0, BTF_FUNC_GLOBAL), 2),
-	};
-
-	return probe_fd(libbpf__load_raw_btf((char *)types, sizeof(types),
-					     strs, sizeof(strs), token_fd));
-}
-
-static int probe_kern_btf_datasec(int token_fd)
-{
-	static const char strs[] = "\0x\0.data";
-	/* static int a; */
-	__u32 types[] = {
-		/* int */
-		BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4),  /* [1] */
-		/* VAR x */                                     /* [2] */
-		BTF_TYPE_ENC(1, BTF_INFO_ENC(BTF_KIND_VAR, 0, 0), 1),
-		BTF_VAR_STATIC,
-		/* DATASEC val */                               /* [3] */
-		BTF_TYPE_ENC(3, BTF_INFO_ENC(BTF_KIND_DATASEC, 0, 1), 4),
-		BTF_VAR_SECINFO_ENC(2, 0, 4),
-	};
-
-	return probe_fd(libbpf__load_raw_btf((char *)types, sizeof(types),
-					     strs, sizeof(strs), token_fd));
-}
-
-static int probe_kern_btf_float(int token_fd)
-{
-	static const char strs[] = "\0float";
-	__u32 types[] = {
-		/* float */
-		BTF_TYPE_FLOAT_ENC(1, 4),
-	};
-
-	return probe_fd(libbpf__load_raw_btf((char *)types, sizeof(types),
-					     strs, sizeof(strs), token_fd));
-}
-
-static int probe_kern_btf_decl_tag(int token_fd)
-{
-	static const char strs[] = "\0tag";
-	__u32 types[] = {
-		/* int */
-		BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4),  /* [1] */
-		/* VAR x */                                     /* [2] */
-		BTF_TYPE_ENC(1, BTF_INFO_ENC(BTF_KIND_VAR, 0, 0), 1),
-		BTF_VAR_STATIC,
-		/* attr */
-		BTF_TYPE_DECL_TAG_ENC(1, 2, -1),
-	};
-
-	return probe_fd(libbpf__load_raw_btf((char *)types, sizeof(types),
-					     strs, sizeof(strs), token_fd));
-}
-
-static int probe_kern_btf_type_tag(int token_fd)
-{
-	static const char strs[] = "\0tag";
-	__u32 types[] = {
-		/* int */
-		BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4),		/* [1] */
-		/* attr */
-		BTF_TYPE_TYPE_TAG_ENC(1, 1),				/* [2] */
-		/* ptr */
-		BTF_TYPE_ENC(0, BTF_INFO_ENC(BTF_KIND_PTR, 0, 0), 2),	/* [3] */
-	};
-
-	return probe_fd(libbpf__load_raw_btf((char *)types, sizeof(types),
-					     strs, sizeof(strs), token_fd));
-}
-
-static int probe_kern_array_mmap(int token_fd)
-{
-	LIBBPF_OPTS(bpf_map_create_opts, opts,
-		.map_flags = BPF_F_MMAPABLE,
-		.token_fd = token_fd,
-	);
-	int fd;
-
-	fd = bpf_map_create(BPF_MAP_TYPE_ARRAY, "libbpf_mmap", sizeof(int), sizeof(int), 1, &opts);
-	return probe_fd(fd);
-}
-
-static int probe_kern_exp_attach_type(int token_fd)
-{
-	LIBBPF_OPTS(bpf_prog_load_opts, opts,
-		.expected_attach_type = BPF_CGROUP_INET_SOCK_CREATE,
-		.token_fd = token_fd,
-	);
-	struct bpf_insn insns[] = {
-		BPF_MOV64_IMM(BPF_REG_0, 0),
-		BPF_EXIT_INSN(),
-	};
-	int fd, insn_cnt = ARRAY_SIZE(insns);
-
-	/* use any valid combination of program type and (optional)
-	 * non-zero expected attach type (i.e., not a BPF_CGROUP_INET_INGRESS)
-	 * to see if kernel supports expected_attach_type field for
-	 * BPF_PROG_LOAD command
-	 */
-	fd = bpf_prog_load(BPF_PROG_TYPE_CGROUP_SOCK, NULL, "GPL", insns, insn_cnt, &opts);
-	return probe_fd(fd);
-}
-
-static int probe_kern_probe_read_kernel(int token_fd)
-{
-	LIBBPF_OPTS(bpf_prog_load_opts, opts, .token_fd = token_fd);
-	struct bpf_insn insns[] = {
-		BPF_MOV64_REG(BPF_REG_1, BPF_REG_10),	/* r1 = r10 (fp) */
-		BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, -8),	/* r1 += -8 */
-		BPF_MOV64_IMM(BPF_REG_2, 8),		/* r2 = 8 */
-		BPF_MOV64_IMM(BPF_REG_3, 0),		/* r3 = 0 */
-		BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_probe_read_kernel),
-		BPF_EXIT_INSN(),
-	};
-	int fd, insn_cnt = ARRAY_SIZE(insns);
-
-	fd = bpf_prog_load(BPF_PROG_TYPE_TRACEPOINT, NULL, "GPL", insns, insn_cnt, &opts);
-	return probe_fd(fd);
-}
-
-static int probe_prog_bind_map(int token_fd)
-{
-	char *cp, errmsg[STRERR_BUFSIZE];
-	struct bpf_insn insns[] = {
-		BPF_MOV64_IMM(BPF_REG_0, 0),
-		BPF_EXIT_INSN(),
-	};
-	LIBBPF_OPTS(bpf_map_create_opts, map_opts, .token_fd = token_fd);
-	LIBBPF_OPTS(bpf_prog_load_opts, prog_opts, .token_fd = token_fd);
-	int ret, map, prog, insn_cnt = ARRAY_SIZE(insns);
-
-	map = bpf_map_create(BPF_MAP_TYPE_ARRAY, "libbpf_det_bind", sizeof(int), 32, 1, &map_opts);
-	if (map < 0) {
-		ret = -errno;
-		cp = libbpf_strerror_r(ret, errmsg, sizeof(errmsg));
-		pr_warn("Error in %s():%s(%d). Couldn't create simple array map.\n",
-			__func__, cp, -ret);
-		return ret;
-	}
-
-	prog = bpf_prog_load(BPF_PROG_TYPE_SOCKET_FILTER, NULL, "GPL", insns, insn_cnt, &prog_opts);
-	if (prog < 0) {
-		close(map);
-		return 0;
-	}
-
-	ret = bpf_prog_bind_map(prog, map, NULL);
-
-	close(map);
-	close(prog);
-
-	return ret >= 0;
-}
-
-static int probe_module_btf(int token_fd)
-{
-	static const char strs[] = "\0int";
-	__u32 types[] = {
-		/* int */
-		BTF_TYPE_INT_ENC(1, BTF_INT_SIGNED, 0, 32, 4),
-	};
-	struct bpf_btf_info info;
-	__u32 len = sizeof(info);
-	char name[16];
-	int fd, err;
-
-	fd = libbpf__load_raw_btf((char *)types, sizeof(types), strs, sizeof(strs), token_fd);
-	if (fd < 0)
-		return 0; /* BTF not supported at all */
-
-	memset(&info, 0, sizeof(info));
-	info.name = ptr_to_u64(name);
-	info.name_len = sizeof(name);
-
-	/* check that BPF_OBJ_GET_INFO_BY_FD supports specifying name pointer;
-	 * kernel's module BTF support coincides with support for
-	 * name/name_len fields in struct bpf_btf_info.
-	 */
-	err = bpf_btf_get_info_by_fd(fd, &info, &len);
-	close(fd);
-	return !err;
-}
-
-static int probe_perf_link(int token_fd)
-{
-	struct bpf_insn insns[] = {
-		BPF_MOV64_IMM(BPF_REG_0, 0),
-		BPF_EXIT_INSN(),
-	};
-	LIBBPF_OPTS(bpf_prog_load_opts, opts, .token_fd = token_fd);
-	int prog_fd, link_fd, err;
-
-	prog_fd = bpf_prog_load(BPF_PROG_TYPE_TRACEPOINT, NULL, "GPL",
-				insns, ARRAY_SIZE(insns), &opts);
-	if (prog_fd < 0)
-		return -errno;
-
-	/* use invalid perf_event FD to get EBADF, if link is supported;
-	 * otherwise EINVAL should be returned
-	 */
-	link_fd = bpf_link_create(prog_fd, -1, BPF_PERF_EVENT, NULL);
-	err = -errno; /* close() can clobber errno */
-
-	if (link_fd >= 0)
-		close(link_fd);
-	close(prog_fd);
-
-	return link_fd < 0 && err == -EBADF;
-}
-
-static int probe_uprobe_multi_link(int token_fd)
-{
-	LIBBPF_OPTS(bpf_prog_load_opts, load_opts,
-		.expected_attach_type = BPF_TRACE_UPROBE_MULTI,
-		.token_fd = token_fd,
-	);
-	LIBBPF_OPTS(bpf_link_create_opts, link_opts);
-	struct bpf_insn insns[] = {
-		BPF_MOV64_IMM(BPF_REG_0, 0),
-		BPF_EXIT_INSN(),
-	};
-	int prog_fd, link_fd, err;
-	unsigned long offset = 0;
-
-	prog_fd = bpf_prog_load(BPF_PROG_TYPE_KPROBE, NULL, "GPL",
-				insns, ARRAY_SIZE(insns), &load_opts);
-	if (prog_fd < 0)
-		return -errno;
-
-	/* Creating uprobe in '/' binary should fail with -EBADF. */
-	link_opts.uprobe_multi.path = "/";
-	link_opts.uprobe_multi.offsets = &offset;
-	link_opts.uprobe_multi.cnt = 1;
-
-	link_fd = bpf_link_create(prog_fd, -1, BPF_TRACE_UPROBE_MULTI, &link_opts);
-	err = -errno; /* close() can clobber errno */
-
-	if (link_fd >= 0)
-		close(link_fd);
-	close(prog_fd);
-
-	return link_fd < 0 && err == -EBADF;
-}
-
-static int probe_kern_bpf_cookie(int token_fd)
-{
-	struct bpf_insn insns[] = {
-		BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_get_attach_cookie),
-		BPF_EXIT_INSN(),
-	};
-	LIBBPF_OPTS(bpf_prog_load_opts, opts, .token_fd = token_fd);
-	int ret, insn_cnt = ARRAY_SIZE(insns);
-
-	ret = bpf_prog_load(BPF_PROG_TYPE_TRACEPOINT, NULL, "GPL", insns, insn_cnt, &opts);
-	return probe_fd(ret);
-}
-
-static int probe_kern_btf_enum64(int token_fd)
-{
-	static const char strs[] = "\0enum64";
-	__u32 types[] = {
-		BTF_TYPE_ENC(1, BTF_INFO_ENC(BTF_KIND_ENUM64, 0, 0), 8),
-	};
-
-	return probe_fd(libbpf__load_raw_btf((char *)types, sizeof(types),
-					     strs, sizeof(strs), token_fd));
-}
-
-typedef int (*feature_probe_fn)(int /* token_fd */);
-
-static struct kern_feature_cache feature_cache;
-
-static struct kern_feature_desc {
-	const char *desc;
-	feature_probe_fn probe;
-} feature_probes[__FEAT_CNT] = {
-	[FEAT_PROG_NAME] = {
-		"BPF program name", probe_kern_prog_name,
-	},
-	[FEAT_GLOBAL_DATA] = {
-		"global variables", probe_kern_global_data,
-	},
-	[FEAT_BTF] = {
-		"minimal BTF", probe_kern_btf,
-	},
-	[FEAT_BTF_FUNC] = {
-		"BTF functions", probe_kern_btf_func,
-	},
-	[FEAT_BTF_GLOBAL_FUNC] = {
-		"BTF global function", probe_kern_btf_func_global,
-	},
-	[FEAT_BTF_DATASEC] = {
-		"BTF data section and variable", probe_kern_btf_datasec,
-	},
-	[FEAT_ARRAY_MMAP] = {
-		"ARRAY map mmap()", probe_kern_array_mmap,
-	},
-	[FEAT_EXP_ATTACH_TYPE] = {
-		"BPF_PROG_LOAD expected_attach_type attribute",
-		probe_kern_exp_attach_type,
-	},
-	[FEAT_PROBE_READ_KERN] = {
-		"bpf_probe_read_kernel() helper", probe_kern_probe_read_kernel,
-	},
-	[FEAT_PROG_BIND_MAP] = {
-		"BPF_PROG_BIND_MAP support", probe_prog_bind_map,
-	},
-	[FEAT_MODULE_BTF] = {
-		"module BTF support", probe_module_btf,
-	},
-	[FEAT_BTF_FLOAT] = {
-		"BTF_KIND_FLOAT support", probe_kern_btf_float,
-	},
-	[FEAT_PERF_LINK] = {
-		"BPF perf link support", probe_perf_link,
-	},
-	[FEAT_BTF_DECL_TAG] = {
-		"BTF_KIND_DECL_TAG support", probe_kern_btf_decl_tag,
-	},
-	[FEAT_BTF_TYPE_TAG] = {
-		"BTF_KIND_TYPE_TAG support", probe_kern_btf_type_tag,
-	},
-	[FEAT_MEMCG_ACCOUNT] = {
-		"memcg-based memory accounting", probe_memcg_account,
-	},
-	[FEAT_BPF_COOKIE] = {
-		"BPF cookie support", probe_kern_bpf_cookie,
-	},
-	[FEAT_BTF_ENUM64] = {
-		"BTF_KIND_ENUM64 support", probe_kern_btf_enum64,
-	},
-	[FEAT_SYSCALL_WRAPPER] = {
-		"Kernel using syscall wrapper", probe_kern_syscall_wrapper,
-	},
-	[FEAT_UPROBE_MULTI_LINK] = {
-		"BPF multi-uprobe link support", probe_uprobe_multi_link,
-	},
-};
-
-bool feat_supported(struct kern_feature_cache *cache, enum kern_feature_id feat_id)
-{
-	struct kern_feature_desc *feat = &feature_probes[feat_id];
-	int ret;
-
-	/* assume global feature cache, unless custom one is provided */
-	if (!cache)
-		cache = &feature_cache;
-
-	if (READ_ONCE(cache->res[feat_id]) == FEAT_UNKNOWN) {
-		ret = feat->probe(cache->token_fd);
-		if (ret > 0) {
-			WRITE_ONCE(cache->res[feat_id], FEAT_SUPPORTED);
-		} else if (ret == 0) {
-			WRITE_ONCE(cache->res[feat_id], FEAT_MISSING);
-		} else {
-			pr_warn("Detection of kernel %s support failed: %d\n", feat->desc, ret);
-			WRITE_ONCE(cache->res[feat_id], FEAT_MISSING);
-		}
-	}
-
-	return READ_ONCE(cache->res[feat_id]) == FEAT_SUPPORTED;
-}
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 4b5ff9508e18..ac54ebc0629f 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -59,8 +59,6 @@
 #define BPF_FS_MAGIC		0xcafe4a11
 #endif
 
-#define BPF_FS_DEFAULT_PATH "/sys/fs/bpf"
-
 #define BPF_INSN_SZ (sizeof(struct bpf_insn))
 
 /* vsprintf() in __base_pr() uses nonliteral format string. It may break
@@ -695,10 +693,6 @@ struct bpf_object {
 
 	struct usdt_manager *usdt_man;
 
-	struct kern_feature_cache *feat_cache;
-	char *token_path;
-	int token_fd;
-
 	char path[];
 };
 
@@ -2198,7 +2192,7 @@ static int build_map_pin_path(struct bpf_map *map, const char *path)
 	int err;
 
 	if (!path)
-		path = BPF_FS_DEFAULT_PATH;
+		path = "/sys/fs/bpf";
 
 	err = pathname_concat(buf, sizeof(buf), path, bpf_map__name(map));
 	if (err)
@@ -3285,7 +3279,7 @@ skip_exception_cb:
 	} else {
 		/* currently BPF_BTF_LOAD only supports log_level 1 */
 		err = btf_load_into_kernel(kern_btf, obj->log_buf, obj->log_size,
-					   obj->log_level ? 1 : 0, obj->token_fd);
+					   obj->log_level ? 1 : 0);
 	}
 	if (sanitize) {
 		if (!err) {
@@ -4608,63 +4602,6 @@ int bpf_map__set_max_entries(struct bpf_map *map, __u32 max_entries)
 	return 0;
 }
 
-static int bpf_object_prepare_token(struct bpf_object *obj)
-{
-	const char *bpffs_path;
-	int bpffs_fd = -1, token_fd, err;
-	bool mandatory;
-	enum libbpf_print_level level;
-
-	/* token is already set up */
-	if (obj->token_fd > 0)
-		return 0;
-	/* token is explicitly prevented */
-	if (obj->token_fd < 0) {
-		pr_debug("object '%s': token is prevented, skipping...\n", obj->name);
-		/* reset to zero to avoid extra checks during map_create and prog_load steps */
-		obj->token_fd = 0;
-		return 0;
-	}
-
-	mandatory = obj->token_path != NULL;
-	level = mandatory ? LIBBPF_WARN : LIBBPF_DEBUG;
-
-	bpffs_path = obj->token_path ?: BPF_FS_DEFAULT_PATH;
-	bpffs_fd = open(bpffs_path, O_DIRECTORY, O_RDWR);
-	if (bpffs_fd < 0) {
-		err = -errno;
-		__pr(level, "object '%s': failed (%d) to open BPF FS mount at '%s'%s\n",
-		     obj->name, err, bpffs_path,
-		     mandatory ? "" : ", skipping optional step...");
-		return mandatory ? err : 0;
-	}
-
-	token_fd = bpf_token_create(bpffs_fd, 0);
-	close(bpffs_fd);
-	if (token_fd < 0) {
-		if (!mandatory && token_fd == -ENOENT) {
-			pr_debug("object '%s': BPF FS at '%s' doesn't have BPF token delegation set up, skipping...\n",
-				 obj->name, bpffs_path);
-			return 0;
-		}
-		__pr(level, "object '%s': failed (%d) to create BPF token from '%s'%s\n",
-		     obj->name, token_fd, bpffs_path,
-		     mandatory ? "" : ", skipping optional step...");
-		return mandatory ? token_fd : 0;
-	}
-
-	obj->feat_cache = calloc(1, sizeof(*obj->feat_cache));
-	if (!obj->feat_cache) {
-		close(token_fd);
-		return -ENOMEM;
-	}
-
-	obj->token_fd = token_fd;
-	obj->feat_cache->token_fd = token_fd;
-
-	return 0;
-}
-
 static int
 bpf_object__probe_loading(struct bpf_object *obj)
 {
@@ -4674,7 +4611,6 @@ bpf_object__probe_loading(struct bpf_object *obj)
 		BPF_EXIT_INSN(),
 	};
 	int ret, insn_cnt = ARRAY_SIZE(insns);
-	LIBBPF_OPTS(bpf_prog_load_opts, opts, .token_fd = obj->token_fd);
 
 	if (obj->gen_loader)
 		return 0;
@@ -4684,9 +4620,9 @@ bpf_object__probe_loading(struct bpf_object *obj)
 		pr_warn("Failed to bump RLIMIT_MEMLOCK (err = %d), you might need to do it explicitly!\n", ret);
 
 	/* make sure basic loading works */
-	ret = bpf_prog_load(BPF_PROG_TYPE_SOCKET_FILTER, NULL, "GPL", insns, insn_cnt, &opts);
+	ret = bpf_prog_load(BPF_PROG_TYPE_SOCKET_FILTER, NULL, "GPL", insns, insn_cnt, NULL);
 	if (ret < 0)
-		ret = bpf_prog_load(BPF_PROG_TYPE_TRACEPOINT, NULL, "GPL", insns, insn_cnt, &opts);
+		ret = bpf_prog_load(BPF_PROG_TYPE_TRACEPOINT, NULL, "GPL", insns, insn_cnt, NULL);
 	if (ret < 0) {
 		ret = errno;
 		cp = libbpf_strerror_r(ret, errmsg, sizeof(errmsg));
@@ -4701,18 +4637,462 @@ bpf_object__probe_loading(struct bpf_object *obj)
 	return 0;
 }
 
+static int probe_fd(int fd)
+{
+	if (fd >= 0)
+		close(fd);
+	return fd >= 0;
+}
+
+static int probe_kern_prog_name(void)
+{
+	const size_t attr_sz = offsetofend(union bpf_attr, prog_name);
+	struct bpf_insn insns[] = {
+		BPF_MOV64_IMM(BPF_REG_0, 0),
+		BPF_EXIT_INSN(),
+	};
+	union bpf_attr attr;
+	int ret;
+
+	memset(&attr, 0, attr_sz);
+	attr.prog_type = BPF_PROG_TYPE_SOCKET_FILTER;
+	attr.license = ptr_to_u64("GPL");
+	attr.insns = ptr_to_u64(insns);
+	attr.insn_cnt = (__u32)ARRAY_SIZE(insns);
+	libbpf_strlcpy(attr.prog_name, "libbpf_nametest", sizeof(attr.prog_name));
+
+	/* make sure loading with name works */
+	ret = sys_bpf_prog_load(&attr, attr_sz, PROG_LOAD_ATTEMPTS);
+	return probe_fd(ret);
+}
+
+static int probe_kern_global_data(void)
+{
+	char *cp, errmsg[STRERR_BUFSIZE];
+	struct bpf_insn insns[] = {
+		BPF_LD_MAP_VALUE(BPF_REG_1, 0, 16),
+		BPF_ST_MEM(BPF_DW, BPF_REG_1, 0, 42),
+		BPF_MOV64_IMM(BPF_REG_0, 0),
+		BPF_EXIT_INSN(),
+	};
+	int ret, map, insn_cnt = ARRAY_SIZE(insns);
+
+	map = bpf_map_create(BPF_MAP_TYPE_ARRAY, "libbpf_global", sizeof(int), 32, 1, NULL);
+	if (map < 0) {
+		ret = -errno;
+		cp = libbpf_strerror_r(ret, errmsg, sizeof(errmsg));
+		pr_warn("Error in %s():%s(%d). Couldn't create simple array map.\n",
+			__func__, cp, -ret);
+		return ret;
+	}
+
+	insns[0].imm = map;
+
+	ret = bpf_prog_load(BPF_PROG_TYPE_SOCKET_FILTER, NULL, "GPL", insns, insn_cnt, NULL);
+	close(map);
+	return probe_fd(ret);
+}
+
+static int probe_kern_btf(void)
+{
+	static const char strs[] = "\0int";
+	__u32 types[] = {
+		/* int */
+		BTF_TYPE_INT_ENC(1, BTF_INT_SIGNED, 0, 32, 4),
+	};
+
+	return probe_fd(libbpf__load_raw_btf((char *)types, sizeof(types),
+					     strs, sizeof(strs)));
+}
+
+static int probe_kern_btf_func(void)
+{
+	static const char strs[] = "\0int\0x\0a";
+	/* void x(int a) {} */
+	__u32 types[] = {
+		/* int */
+		BTF_TYPE_INT_ENC(1, BTF_INT_SIGNED, 0, 32, 4),  /* [1] */
+		/* FUNC_PROTO */                                /* [2] */
+		BTF_TYPE_ENC(0, BTF_INFO_ENC(BTF_KIND_FUNC_PROTO, 0, 1), 0),
+		BTF_PARAM_ENC(7, 1),
+		/* FUNC x */                                    /* [3] */
+		BTF_TYPE_ENC(5, BTF_INFO_ENC(BTF_KIND_FUNC, 0, 0), 2),
+	};
+
+	return probe_fd(libbpf__load_raw_btf((char *)types, sizeof(types),
+					     strs, sizeof(strs)));
+}
+
+static int probe_kern_btf_func_global(void)
+{
+	static const char strs[] = "\0int\0x\0a";
+	/* static void x(int a) {} */
+	__u32 types[] = {
+		/* int */
+		BTF_TYPE_INT_ENC(1, BTF_INT_SIGNED, 0, 32, 4),  /* [1] */
+		/* FUNC_PROTO */                                /* [2] */
+		BTF_TYPE_ENC(0, BTF_INFO_ENC(BTF_KIND_FUNC_PROTO, 0, 1), 0),
+		BTF_PARAM_ENC(7, 1),
+		/* FUNC x BTF_FUNC_GLOBAL */                    /* [3] */
+		BTF_TYPE_ENC(5, BTF_INFO_ENC(BTF_KIND_FUNC, 0, BTF_FUNC_GLOBAL), 2),
+	};
+
+	return probe_fd(libbpf__load_raw_btf((char *)types, sizeof(types),
+					     strs, sizeof(strs)));
+}
+
+static int probe_kern_btf_datasec(void)
+{
+	static const char strs[] = "\0x\0.data";
+	/* static int a; */
+	__u32 types[] = {
+		/* int */
+		BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4),  /* [1] */
+		/* VAR x */                                     /* [2] */
+		BTF_TYPE_ENC(1, BTF_INFO_ENC(BTF_KIND_VAR, 0, 0), 1),
+		BTF_VAR_STATIC,
+		/* DATASEC val */                               /* [3] */
+		BTF_TYPE_ENC(3, BTF_INFO_ENC(BTF_KIND_DATASEC, 0, 1), 4),
+		BTF_VAR_SECINFO_ENC(2, 0, 4),
+	};
+
+	return probe_fd(libbpf__load_raw_btf((char *)types, sizeof(types),
+					     strs, sizeof(strs)));
+}
+
+static int probe_kern_btf_float(void)
+{
+	static const char strs[] = "\0float";
+	__u32 types[] = {
+		/* float */
+		BTF_TYPE_FLOAT_ENC(1, 4),
+	};
+
+	return probe_fd(libbpf__load_raw_btf((char *)types, sizeof(types),
+					     strs, sizeof(strs)));
+}
+
+static int probe_kern_btf_decl_tag(void)
+{
+	static const char strs[] = "\0tag";
+	__u32 types[] = {
+		/* int */
+		BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4),  /* [1] */
+		/* VAR x */                                     /* [2] */
+		BTF_TYPE_ENC(1, BTF_INFO_ENC(BTF_KIND_VAR, 0, 0), 1),
+		BTF_VAR_STATIC,
+		/* attr */
+		BTF_TYPE_DECL_TAG_ENC(1, 2, -1),
+	};
+
+	return probe_fd(libbpf__load_raw_btf((char *)types, sizeof(types),
+					     strs, sizeof(strs)));
+}
+
+static int probe_kern_btf_type_tag(void)
+{
+	static const char strs[] = "\0tag";
+	__u32 types[] = {
+		/* int */
+		BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4),		/* [1] */
+		/* attr */
+		BTF_TYPE_TYPE_TAG_ENC(1, 1),				/* [2] */
+		/* ptr */
+		BTF_TYPE_ENC(0, BTF_INFO_ENC(BTF_KIND_PTR, 0, 0), 2),	/* [3] */
+	};
+
+	return probe_fd(libbpf__load_raw_btf((char *)types, sizeof(types),
+					     strs, sizeof(strs)));
+}
+
+static int probe_kern_array_mmap(void)
+{
+	LIBBPF_OPTS(bpf_map_create_opts, opts, .map_flags = BPF_F_MMAPABLE);
+	int fd;
+
+	fd = bpf_map_create(BPF_MAP_TYPE_ARRAY, "libbpf_mmap", sizeof(int), sizeof(int), 1, &opts);
+	return probe_fd(fd);
+}
+
+static int probe_kern_exp_attach_type(void)
+{
+	LIBBPF_OPTS(bpf_prog_load_opts, opts, .expected_attach_type = BPF_CGROUP_INET_SOCK_CREATE);
+	struct bpf_insn insns[] = {
+		BPF_MOV64_IMM(BPF_REG_0, 0),
+		BPF_EXIT_INSN(),
+	};
+	int fd, insn_cnt = ARRAY_SIZE(insns);
+
+	/* use any valid combination of program type and (optional)
+	 * non-zero expected attach type (i.e., not a BPF_CGROUP_INET_INGRESS)
+	 * to see if kernel supports expected_attach_type field for
+	 * BPF_PROG_LOAD command
+	 */
+	fd = bpf_prog_load(BPF_PROG_TYPE_CGROUP_SOCK, NULL, "GPL", insns, insn_cnt, &opts);
+	return probe_fd(fd);
+}
+
+static int probe_kern_probe_read_kernel(void)
+{
+	struct bpf_insn insns[] = {
+		BPF_MOV64_REG(BPF_REG_1, BPF_REG_10),	/* r1 = r10 (fp) */
+		BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, -8),	/* r1 += -8 */
+		BPF_MOV64_IMM(BPF_REG_2, 8),		/* r2 = 8 */
+		BPF_MOV64_IMM(BPF_REG_3, 0),		/* r3 = 0 */
+		BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_probe_read_kernel),
+		BPF_EXIT_INSN(),
+	};
+	int fd, insn_cnt = ARRAY_SIZE(insns);
+
+	fd = bpf_prog_load(BPF_PROG_TYPE_TRACEPOINT, NULL, "GPL", insns, insn_cnt, NULL);
+	return probe_fd(fd);
+}
+
+static int probe_prog_bind_map(void)
+{
+	char *cp, errmsg[STRERR_BUFSIZE];
+	struct bpf_insn insns[] = {
+		BPF_MOV64_IMM(BPF_REG_0, 0),
+		BPF_EXIT_INSN(),
+	};
+	int ret, map, prog, insn_cnt = ARRAY_SIZE(insns);
+
+	map = bpf_map_create(BPF_MAP_TYPE_ARRAY, "libbpf_det_bind", sizeof(int), 32, 1, NULL);
+	if (map < 0) {
+		ret = -errno;
+		cp = libbpf_strerror_r(ret, errmsg, sizeof(errmsg));
+		pr_warn("Error in %s():%s(%d). Couldn't create simple array map.\n",
+			__func__, cp, -ret);
+		return ret;
+	}
+
+	prog = bpf_prog_load(BPF_PROG_TYPE_SOCKET_FILTER, NULL, "GPL", insns, insn_cnt, NULL);
+	if (prog < 0) {
+		close(map);
+		return 0;
+	}
+
+	ret = bpf_prog_bind_map(prog, map, NULL);
+
+	close(map);
+	close(prog);
+
+	return ret >= 0;
+}
+
+static int probe_module_btf(void)
+{
+	static const char strs[] = "\0int";
+	__u32 types[] = {
+		/* int */
+		BTF_TYPE_INT_ENC(1, BTF_INT_SIGNED, 0, 32, 4),
+	};
+	struct bpf_btf_info info;
+	__u32 len = sizeof(info);
+	char name[16];
+	int fd, err;
+
+	fd = libbpf__load_raw_btf((char *)types, sizeof(types), strs, sizeof(strs));
+	if (fd < 0)
+		return 0; /* BTF not supported at all */
+
+	memset(&info, 0, sizeof(info));
+	info.name = ptr_to_u64(name);
+	info.name_len = sizeof(name);
+
+	/* check that BPF_OBJ_GET_INFO_BY_FD supports specifying name pointer;
+	 * kernel's module BTF support coincides with support for
+	 * name/name_len fields in struct bpf_btf_info.
+	 */
+	err = bpf_btf_get_info_by_fd(fd, &info, &len);
+	close(fd);
+	return !err;
+}
+
+static int probe_perf_link(void)
+{
+	struct bpf_insn insns[] = {
+		BPF_MOV64_IMM(BPF_REG_0, 0),
+		BPF_EXIT_INSN(),
+	};
+	int prog_fd, link_fd, err;
+
+	prog_fd = bpf_prog_load(BPF_PROG_TYPE_TRACEPOINT, NULL, "GPL",
+				insns, ARRAY_SIZE(insns), NULL);
+	if (prog_fd < 0)
+		return -errno;
+
+	/* use invalid perf_event FD to get EBADF, if link is supported;
+	 * otherwise EINVAL should be returned
+	 */
+	link_fd = bpf_link_create(prog_fd, -1, BPF_PERF_EVENT, NULL);
+	err = -errno; /* close() can clobber errno */
+
+	if (link_fd >= 0)
+		close(link_fd);
+	close(prog_fd);
+
+	return link_fd < 0 && err == -EBADF;
+}
+
+static int probe_uprobe_multi_link(void)
+{
+	LIBBPF_OPTS(bpf_prog_load_opts, load_opts,
+		.expected_attach_type = BPF_TRACE_UPROBE_MULTI,
+	);
+	LIBBPF_OPTS(bpf_link_create_opts, link_opts);
+	struct bpf_insn insns[] = {
+		BPF_MOV64_IMM(BPF_REG_0, 0),
+		BPF_EXIT_INSN(),
+	};
+	int prog_fd, link_fd, err;
+	unsigned long offset = 0;
+
+	prog_fd = bpf_prog_load(BPF_PROG_TYPE_KPROBE, NULL, "GPL",
+				insns, ARRAY_SIZE(insns), &load_opts);
+	if (prog_fd < 0)
+		return -errno;
+
+	/* Creating uprobe in '/' binary should fail with -EBADF. */
+	link_opts.uprobe_multi.path = "/";
+	link_opts.uprobe_multi.offsets = &offset;
+	link_opts.uprobe_multi.cnt = 1;
+
+	link_fd = bpf_link_create(prog_fd, -1, BPF_TRACE_UPROBE_MULTI, &link_opts);
+	err = -errno; /* close() can clobber errno */
+
+	if (link_fd >= 0)
+		close(link_fd);
+	close(prog_fd);
+
+	return link_fd < 0 && err == -EBADF;
+}
+
+static int probe_kern_bpf_cookie(void)
+{
+	struct bpf_insn insns[] = {
+		BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_get_attach_cookie),
+		BPF_EXIT_INSN(),
+	};
+	int ret, insn_cnt = ARRAY_SIZE(insns);
+
+	ret = bpf_prog_load(BPF_PROG_TYPE_KPROBE, NULL, "GPL", insns, insn_cnt, NULL);
+	return probe_fd(ret);
+}
+
+static int probe_kern_btf_enum64(void)
+{
+	static const char strs[] = "\0enum64";
+	__u32 types[] = {
+		BTF_TYPE_ENC(1, BTF_INFO_ENC(BTF_KIND_ENUM64, 0, 0), 8),
+	};
+
+	return probe_fd(libbpf__load_raw_btf((char *)types, sizeof(types),
+					     strs, sizeof(strs)));
+}
+
+static int probe_kern_syscall_wrapper(void);
+
+enum kern_feature_result {
+	FEAT_UNKNOWN = 0,
+	FEAT_SUPPORTED = 1,
+	FEAT_MISSING = 2,
+};
+
+typedef int (*feature_probe_fn)(void);
+
+static struct kern_feature_desc {
+	const char *desc;
+	feature_probe_fn probe;
+	enum kern_feature_result res;
+} feature_probes[__FEAT_CNT] = {
+	[FEAT_PROG_NAME] = {
+		"BPF program name", probe_kern_prog_name,
+	},
+	[FEAT_GLOBAL_DATA] = {
+		"global variables", probe_kern_global_data,
+	},
+	[FEAT_BTF] = {
+		"minimal BTF", probe_kern_btf,
+	},
+	[FEAT_BTF_FUNC] = {
+		"BTF functions", probe_kern_btf_func,
+	},
+	[FEAT_BTF_GLOBAL_FUNC] = {
+		"BTF global function", probe_kern_btf_func_global,
+	},
+	[FEAT_BTF_DATASEC] = {
+		"BTF data section and variable", probe_kern_btf_datasec,
+	},
+	[FEAT_ARRAY_MMAP] = {
+		"ARRAY map mmap()", probe_kern_array_mmap,
+	},
+	[FEAT_EXP_ATTACH_TYPE] = {
+		"BPF_PROG_LOAD expected_attach_type attribute",
+		probe_kern_exp_attach_type,
+	},
+	[FEAT_PROBE_READ_KERN] = {
+		"bpf_probe_read_kernel() helper", probe_kern_probe_read_kernel,
+	},
+	[FEAT_PROG_BIND_MAP] = {
+		"BPF_PROG_BIND_MAP support", probe_prog_bind_map,
+	},
+	[FEAT_MODULE_BTF] = {
+		"module BTF support", probe_module_btf,
+	},
+	[FEAT_BTF_FLOAT] = {
+		"BTF_KIND_FLOAT support", probe_kern_btf_float,
+	},
+	[FEAT_PERF_LINK] = {
+		"BPF perf link support", probe_perf_link,
+	},
+	[FEAT_BTF_DECL_TAG] = {
+		"BTF_KIND_DECL_TAG support", probe_kern_btf_decl_tag,
+	},
+	[FEAT_BTF_TYPE_TAG] = {
+		"BTF_KIND_TYPE_TAG support", probe_kern_btf_type_tag,
+	},
+	[FEAT_MEMCG_ACCOUNT] = {
+		"memcg-based memory accounting", probe_memcg_account,
+	},
+	[FEAT_BPF_COOKIE] = {
+		"BPF cookie support", probe_kern_bpf_cookie,
+	},
+	[FEAT_BTF_ENUM64] = {
+		"BTF_KIND_ENUM64 support", probe_kern_btf_enum64,
+	},
+	[FEAT_SYSCALL_WRAPPER] = {
+		"Kernel using syscall wrapper", probe_kern_syscall_wrapper,
+	},
+	[FEAT_UPROBE_MULTI_LINK] = {
+		"BPF multi-uprobe link support", probe_uprobe_multi_link,
+	},
+};
+
 bool kernel_supports(const struct bpf_object *obj, enum kern_feature_id feat_id)
 {
+	struct kern_feature_desc *feat = &feature_probes[feat_id];
+	int ret;
+
 	if (obj && obj->gen_loader)
 		/* To generate loader program assume the latest kernel
 		 * to avoid doing extra prog_load, map_create syscalls.
 		 */
 		return true;
 
-	if (obj->token_fd)
-		return feat_supported(obj->feat_cache, feat_id);
+	if (READ_ONCE(feat->res) == FEAT_UNKNOWN) {
+		ret = feat->probe();
+		if (ret > 0) {
+			WRITE_ONCE(feat->res, FEAT_SUPPORTED);
+		} else if (ret == 0) {
+			WRITE_ONCE(feat->res, FEAT_MISSING);
+		} else {
+			pr_warn("Detection of kernel %s support failed: %d\n", feat->desc, ret);
+			WRITE_ONCE(feat->res, FEAT_MISSING);
+		}
+	}
 
-	return feat_supported(NULL, feat_id);
+	return READ_ONCE(feat->res) == FEAT_SUPPORTED;
 }
 
 static bool map_is_reuse_compat(const struct bpf_map *map, int map_fd)
@@ -4831,7 +5211,6 @@ static int bpf_object__create_map(struct bpf_object *obj, struct bpf_map *map, b
 	create_attr.map_flags = def->map_flags;
 	create_attr.numa_node = map->numa_node;
 	create_attr.map_extra = map->map_extra;
-	create_attr.token_fd = obj->token_fd;
 
 	if (bpf_map__is_struct_ops(map))
 		create_attr.btf_vmlinux_value_type_id = map->btf_vmlinux_value_type_id;
@@ -6667,7 +7046,6 @@ static int bpf_object_load_prog(struct bpf_object *obj, struct bpf_program *prog
 	load_attr.attach_btf_id = prog->attach_btf_id;
 	load_attr.kern_version = kern_version;
 	load_attr.prog_ifindex = prog->prog_ifindex;
-	load_attr.token_fd = obj->token_fd;
 
 	/* specify func_info/line_info only if kernel supports them */
 	btf_fd = bpf_object__btf_fd(obj);
@@ -7129,10 +7507,10 @@ static int bpf_object_init_progs(struct bpf_object *obj, const struct bpf_object
 static struct bpf_object *bpf_object_open(const char *path, const void *obj_buf, size_t obj_buf_sz,
 					  const struct bpf_object_open_opts *opts)
 {
-	const char *obj_name, *kconfig, *btf_tmp_path, *token_path;
+	const char *obj_name, *kconfig, *btf_tmp_path;
 	struct bpf_object *obj;
 	char tmp_name[64];
-	int err, token_fd;
+	int err;
 	char *log_buf;
 	size_t log_size;
 	__u32 log_level;
@@ -7166,28 +7544,6 @@ static struct bpf_object *bpf_object_open(const char *path, const void *obj_buf,
 	if (log_size && !log_buf)
 		return ERR_PTR(-EINVAL);
 
-	token_path = OPTS_GET(opts, bpf_token_path, NULL);
-	token_fd = OPTS_GET(opts, bpf_token_fd, -1);
-	/* non-empty token path can't be combined with invalid token FD */
-	if (token_path && token_path[0] != '\0' && token_fd < 0)
-		return ERR_PTR(-EINVAL);
-	/* empty token path can't be combined with valid token FD */
-	if (token_path && token_path[0] == '\0' && token_fd > 0)
-		return ERR_PTR(-EINVAL);
-	/* if user didn't specify bpf_token_path/bpf_token_fd explicitly,
-	 * check if LIBBPF_BPF_TOKEN_PATH envvar was set and treat it as
-	 * bpf_token_path option
-	 */
-	if (token_fd == 0 && !token_path)
-		token_path = getenv("LIBBPF_BPF_TOKEN_PATH");
-	/* empty token_path is equivalent to invalid token_fd */
-	if (token_path && token_path[0] == '\0') {
-		token_path = NULL;
-		token_fd = -1;
-	}
-	if (token_path && strlen(token_path) >= PATH_MAX)
-		return ERR_PTR(-ENAMETOOLONG);
-
 	obj = bpf_object__new(path, obj_buf, obj_buf_sz, obj_name);
 	if (IS_ERR(obj))
 		return obj;
@@ -7196,19 +7552,6 @@ static struct bpf_object *bpf_object_open(const char *path, const void *obj_buf,
 	obj->log_size = log_size;
 	obj->log_level = log_level;
 
-	obj->token_fd = token_fd <= 0 ? token_fd : dup_good_fd(token_fd);
-	if (token_fd > 0 && obj->token_fd < 0) {
-		err = -errno;
-		goto out;
-	}
-	if (token_path) {
-		obj->token_path = strdup(token_path);
-		if (!obj->token_path) {
-			err = -ENOMEM;
-			goto out;
-		}
-	}
-
 	btf_tmp_path = OPTS_GET(opts, btf_custom_path, NULL);
 	if (btf_tmp_path) {
 		if (strlen(btf_tmp_path) >= PATH_MAX) {
@@ -7719,8 +8062,7 @@ static int bpf_object_load(struct bpf_object *obj, int extra_log_level, const ch
 	if (obj->gen_loader)
 		bpf_gen__init(obj->gen_loader, extra_log_level, obj->nr_programs, obj->nr_maps);
 
-	err = bpf_object_prepare_token(obj);
-	err = err ? : bpf_object__probe_loading(obj);
+	err = bpf_object__probe_loading(obj);
 	err = err ? : bpf_object__load_vmlinux_btf(obj, false);
 	err = err ? : bpf_object__resolve_externs(obj, obj->kconfig);
 	err = err ? : bpf_object__sanitize_and_load_btf(obj);
@@ -8257,11 +8599,6 @@ void bpf_object__close(struct bpf_object *obj)
 	}
 	zfree(&obj->programs);
 
-	zfree(&obj->feat_cache);
-	zfree(&obj->token_path);
-	if (obj->token_fd > 0)
-		close(obj->token_fd);
-
 	free(obj);
 }
 
@@ -10275,7 +10612,7 @@ static const char *arch_specific_syscall_pfx(void)
 #endif
 }
 
-int probe_kern_syscall_wrapper(int token_fd)
+static int probe_kern_syscall_wrapper(void)
 {
 	char syscall_name[64];
 	const char *ksys_pfx;
diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h
index 916904bd2a7a..6cd9c501624f 100644
--- a/tools/lib/bpf/libbpf.h
+++ b/tools/lib/bpf/libbpf.h
@@ -177,45 +177,10 @@ struct bpf_object_open_opts {
 	 * logs through its print callback.
 	 */
 	__u32 kernel_log_level;
-	/* FD of a BPF token instantiated by user through bpf_token_create()
-	 * API. BPF object will keep dup()'ed FD internally, so passed token
-	 * FD can be closed after BPF object/skeleton open step.
-	 *
-	 * Setting bpf_token_fd to negative value disables libbpf's automatic
-	 * attempt to create BPF token from default BPF FS mount point
-	 * (/sys/fs/bpf), in case this default behavior is undesirable.
-	 *
-	 * If bpf_token_path and bpf_token_fd are not specified, libbpf will
-	 * consult LIBBPF_BPF_TOKEN_PATH environment variable. If set, it will
-	 * be taken as a value of bpf_token_path option and will force libbpf
-	 * to either create BPF token from provided custom BPF FS path, or
-	 * will disable implicit BPF token creation, if envvar value is an
-	 * empty string.
-	 *
-	 * bpf_token_path and bpf_token_fd are mutually exclusive and only one
-	 * of those options should be set. Either of them overrides
-	 * LIBBPF_BPF_TOKEN_PATH envvar.
-	 */
-	int bpf_token_fd;
-	/* Path to BPF FS mount point to derive BPF token from.
-	 *
-	 * Created BPF token will be used for all bpf() syscall operations
-	 * that accept BPF token (e.g., map creation, BTF and program loads,
-	 * etc) automatically within instantiated BPF object.
-	 *
-	 * Setting bpf_token_path option to empty string disables libbpf's
-	 * automatic attempt to create BPF token from default BPF FS mount
-	 * point (/sys/fs/bpf), in case this default behavior is undesirable.
-	 *
-	 * bpf_token_path and bpf_token_fd are mutually exclusive and only one
-	 * of those options should be set. Either of them overrides
-	 * LIBBPF_BPF_TOKEN_PATH envvar.
-	 */
-	const char *bpf_token_path;
 
 	size_t :0;
 };
-#define bpf_object_open_opts__last_field bpf_token_path
+#define bpf_object_open_opts__last_field kernel_log_level
 
 /**
  * @brief **bpf_object__open()** creates a bpf_object by opening
diff --git a/tools/lib/bpf/libbpf.map b/tools/lib/bpf/libbpf.map
index df7657b65c47..91c5aef7dae7 100644
--- a/tools/lib/bpf/libbpf.map
+++ b/tools/lib/bpf/libbpf.map
@@ -401,7 +401,6 @@ LIBBPF_1.3.0 {
 		bpf_program__attach_netkit;
 		bpf_program__attach_tcx;
 		bpf_program__attach_uprobe_multi;
-		bpf_token_create;
 		ring__avail_data_size;
 		ring__consume;
 		ring__consumer_pos;
diff --git a/tools/lib/bpf/libbpf_internal.h b/tools/lib/bpf/libbpf_internal.h
index 4cda32298c49..b5d334754e5d 100644
--- a/tools/lib/bpf/libbpf_internal.h
+++ b/tools/lib/bpf/libbpf_internal.h
@@ -360,32 +360,15 @@ enum kern_feature_id {
 	__FEAT_CNT,
 };
 
-enum kern_feature_result {
-	FEAT_UNKNOWN = 0,
-	FEAT_SUPPORTED = 1,
-	FEAT_MISSING = 2,
-};
-
-struct kern_feature_cache {
-	enum kern_feature_result res[__FEAT_CNT];
-	int token_fd;
-};
-
-bool feat_supported(struct kern_feature_cache *cache, enum kern_feature_id feat_id);
+int probe_memcg_account(void);
 bool kernel_supports(const struct bpf_object *obj, enum kern_feature_id feat_id);
-
-int probe_kern_syscall_wrapper(int token_fd);
-int probe_memcg_account(int token_fd);
 int bump_rlimit_memlock(void);
 
 int parse_cpu_mask_str(const char *s, bool **mask, int *mask_sz);
 int parse_cpu_mask_file(const char *fcpu, bool **mask, int *mask_sz);
 int libbpf__load_raw_btf(const char *raw_types, size_t types_len,
-			 const char *str_sec, size_t str_len,
-			 int token_fd);
-int btf_load_into_kernel(struct btf *btf,
-			 char *log_buf, size_t log_sz, __u32 log_level,
-			 int token_fd);
+			 const char *str_sec, size_t str_len);
+int btf_load_into_kernel(struct btf *btf, char *log_buf, size_t log_sz, __u32 log_level);
 
 struct btf *btf_get_from_fd(int btf_fd, struct btf *base_btf);
 void btf_get_kernel_prefix_kind(enum bpf_attach_type attach_type,
@@ -549,17 +532,6 @@ static inline bool is_ldimm64_insn(struct bpf_insn *insn)
 	return insn->code == (BPF_LD | BPF_IMM | BPF_DW);
 }
 
-/* Unconditionally dup FD, ensuring it doesn't use [0, 2] range.
- * Original FD is not closed or altered in any other way.
- * Preserves original FD value, if it's invalid (negative).
- */
-static inline int dup_good_fd(int fd)
-{
-	if (fd < 0)
-		return fd;
-	return fcntl(fd, F_DUPFD_CLOEXEC, 3);
-}
-
 /* if fd is stdin, stdout, or stderr, dup to a fd greater than 2
  * Takes ownership of the fd passed in, and closes it if calling
  * fcntl(fd, F_DUPFD_CLOEXEC, 3).
@@ -571,7 +543,7 @@ static inline int ensure_good_fd(int fd)
 	if (fd < 0)
 		return fd;
 	if (fd < 3) {
-		fd = dup_good_fd(fd);
+		fd = fcntl(fd, F_DUPFD_CLOEXEC, 3);
 		saved_errno = errno;
 		close(old_fd);
 		errno = saved_errno;
diff --git a/tools/lib/bpf/libbpf_probes.c b/tools/lib/bpf/libbpf_probes.c
index 8e7437006639..9c4db90b92b6 100644
--- a/tools/lib/bpf/libbpf_probes.c
+++ b/tools/lib/bpf/libbpf_probes.c
@@ -219,8 +219,7 @@ int libbpf_probe_bpf_prog_type(enum bpf_prog_type prog_type, const void *opts)
 }
 
 int libbpf__load_raw_btf(const char *raw_types, size_t types_len,
-			 const char *str_sec, size_t str_len,
-			 int token_fd)
+			 const char *str_sec, size_t str_len)
 {
 	struct btf_header hdr = {
 		.magic = BTF_MAGIC,
@@ -230,7 +229,6 @@ int libbpf__load_raw_btf(const char *raw_types, size_t types_len,
 		.str_off = types_len,
 		.str_len = str_len,
 	};
-	LIBBPF_OPTS(bpf_btf_load_opts, opts, .token_fd = token_fd);
 	int btf_fd, btf_len;
 	__u8 *raw_btf;
 
@@ -243,7 +241,7 @@ int libbpf__load_raw_btf(const char *raw_types, size_t types_len,
 	memcpy(raw_btf + hdr.hdr_len, raw_types, hdr.type_len);
 	memcpy(raw_btf + hdr.hdr_len + hdr.type_len, str_sec, hdr.str_len);
 
-	btf_fd = bpf_btf_load(raw_btf, btf_len, &opts);
+	btf_fd = bpf_btf_load(raw_btf, btf_len, NULL);
 
 	free(raw_btf);
 	return btf_fd;
@@ -273,7 +271,7 @@ static int load_local_storage_btf(void)
 	};
 
 	return libbpf__load_raw_btf((char *)types, sizeof(types),
-				     strs, sizeof(strs), 0);
+				     strs, sizeof(strs));
 }
 
 static int probe_map_create(enum bpf_map_type map_type)
diff --git a/tools/lib/bpf/str_error.h b/tools/lib/bpf/str_error.h
index 626d7ffb03d6..a139334d57b6 100644
--- a/tools/lib/bpf/str_error.h
+++ b/tools/lib/bpf/str_error.h
@@ -2,8 +2,5 @@
 #ifndef __LIBBPF_STR_ERROR_H
 #define __LIBBPF_STR_ERROR_H
 
-#define STRERR_BUFSIZE  128
-
 char *libbpf_strerror_r(int err, char *dst, int len);
-
 #endif /* __LIBBPF_STR_ERROR_H */