diff options
Diffstat (limited to 'tools')
| -rw-r--r-- | tools/lib/bpf/libbpf.c | 103 |
1 files changed, 58 insertions, 45 deletions
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index efd857ebd5ee..460e5790a95f 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -2338,18 +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); @@ -2402,17 +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 || @@ -2530,30 +2524,50 @@ static int bpf_object__load_vmlinux_btf(struct bpf_object *obj) 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 *orig_data; + void *san_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 */ + orig_data = btf__get_raw_data(obj->btf, &sz); + san_data = malloc(sz); + if (!san_data) + return -ENOMEM; + memcpy(san_data, orig_data, sz); + kern_btf = btf__new(san_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) @@ -3777,7 +3791,7 @@ 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; @@ -5361,18 +5375,17 @@ 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; |