#include #include #include #include #include #include #include #include #include #include #include #include "build-id.h" #include "util.h" #include "debug.h" #include "machine.h" #include "symbol.h" #include "strlist.h" #include "intlist.h" #include "header.h" #include #include #include #include static int dso__load_kernel_sym(struct dso *dso, struct map *map, symbol_filter_t filter); static int dso__load_guest_kernel_sym(struct dso *dso, struct map *map, symbol_filter_t filter); int vmlinux_path__nr_entries; char **vmlinux_path; struct symbol_conf symbol_conf = { .use_modules = true, .try_vmlinux_path = true, .annotate_src = true, .demangle = true, .demangle_kernel = false, .cumulate_callchain = true, .show_hist_headers = true, .symfs = "", .event_group = true, }; static enum dso_binary_type binary_type_symtab[] = { DSO_BINARY_TYPE__KALLSYMS, DSO_BINARY_TYPE__GUEST_KALLSYMS, DSO_BINARY_TYPE__JAVA_JIT, DSO_BINARY_TYPE__DEBUGLINK, DSO_BINARY_TYPE__BUILD_ID_CACHE, DSO_BINARY_TYPE__FEDORA_DEBUGINFO, DSO_BINARY_TYPE__UBUNTU_DEBUGINFO, DSO_BINARY_TYPE__BUILDID_DEBUGINFO, DSO_BINARY_TYPE__SYSTEM_PATH_DSO, DSO_BINARY_TYPE__GUEST_KMODULE, DSO_BINARY_TYPE__GUEST_KMODULE_COMP, DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE, DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP, DSO_BINARY_TYPE__OPENEMBEDDED_DEBUGINFO, DSO_BINARY_TYPE__NOT_FOUND, }; #define DSO_BINARY_TYPE__SYMTAB_CNT ARRAY_SIZE(binary_type_symtab) bool symbol_type__is_a(char symbol_type, enum map_type map_type) { symbol_type = toupper(symbol_type); switch (map_type) { case MAP__FUNCTION: return symbol_type == 'T' || symbol_type == 'W'; case MAP__VARIABLE: return symbol_type == 'D'; default: return false; } } static int prefix_underscores_count(const char *str) { const char *tail = str; while (*tail == '_') tail++; return tail - str; } int __weak arch__choose_best_symbol(struct symbol *syma, struct symbol *symb __maybe_unused) { /* Avoid "SyS" kernel syscall aliases */ if (strlen(syma->name) >= 3 && !strncmp(syma->name, "SyS", 3)) return SYMBOL_B; if (strlen(syma->name) >= 10 && !strncmp(syma->name, "compat_SyS", 10)) return SYMBOL_B; return SYMBOL_A; } static int choose_best_symbol(struct symbol *syma, struct symbol *symb) { s64 a; s64 b; size_t na, nb; /* Prefer a symbol with non zero length */ a = syma->end - syma->start; b = symb->end - symb->start; if ((b == 0) && (a > 0)) return SYMBOL_A; else if ((a == 0) && (b > 0)) return SYMBOL_B; /* Prefer a non weak symbol over a weak one */ a = syma->binding == STB_WEAK; b = symb->binding == STB_WEAK; if (b && !a) return SYMBOL_A; if (a && !b) return SYMBOL_B; /* Prefer a global symbol over a non global one */ a = syma->binding == STB_GLOBAL; b = symb->binding == STB_GLOBAL; if (a && !b) return SYMBOL_A; if (b && !a) return SYMBOL_B; /* Prefer a symbol with less underscores */ a = prefix_underscores_count(syma->name); b = prefix_underscores_count(symb->name); if (b > a) return SYMBOL_A; else if (a > b) return SYMBOL_B; /* Choose the symbol with the longest name */ na = strlen(syma->name); nb = strlen(symb->name); if (na > nb) return SYMBOL_A; else if (na < nb) return SYMBOL_B; return arch__choose_best_symbol(syma, symb); } void symbols__fixup_duplicate(struct rb_root *symbols) { struct rb_node *nd; struct symbol *curr, *next; nd = rb_first(symbols); while (nd) { curr = rb_entry(nd, struct symbol, rb_node); again: nd = rb_next(&curr->rb_node); next = rb_entry(nd, struct symbol, rb_node); if (!nd) break; if (curr->start != next->start) continue; if (choose_best_symbol(curr, next) == SYMBOL_A) { rb_erase(&next->rb_node, symbols); symbol__delete(next); goto again; } else { nd = rb_next(&curr->rb_node); rb_erase(&curr->rb_node, symbols); symbol__delete(curr); } } } void symbols__fixup_end(struct rb_root *symbols) { struct rb_node *nd, *prevnd = rb_first(symbols); struct symbol *curr, *prev; if (prevnd == NULL) return; curr = rb_entry(prevnd, struct symbol, rb_node); for (nd = rb_next(prevnd); nd; nd = rb_next(nd)) { prev = curr; curr = rb_entry(nd, struct symbol, rb_node); if (prev->end == prev->start && prev->end != curr->start) prev->end = curr->start; } /* Last entry */ if (curr->end == curr->start) curr->end = roundup(curr->start, 4096); } void __map_groups__fixup_end(struct map_groups *mg, enum map_type type) { struct maps *maps = &mg->maps[type]; struct map *next, *curr; pthread_rwlock_wrlock(&maps->lock); curr = maps__first(maps); if (curr == NULL) goto out_unlock; for (next = map__next(curr); next; next = map__next(curr)) { curr->end = next->start; curr = next; } /* * We still haven't the actual symbols, so guess the * last map final address. */ curr->end = ~0ULL; out_unlock: pthread_rwlock_unlock(&maps->lock); } struct symbol *symbol__new(u64 start, u64 len, u8 binding, const char *name) { size_t namelen = strlen(name) + 1; struct symbol *sym = calloc(1, (symbol_conf.priv_size + sizeof(*sym) + namelen)); if (sym == NULL) return NULL; if (symbol_conf.priv_size) sym = ((void *)sym) + symbol_conf.priv_size; sym->start = start; sym->end = len ? start + len : start; sym->binding = binding; sym->namelen = namelen - 1; pr_debug4("%s: %s %#" PRIx64 "-%#" PRIx64 "\n", __func__, name, start, sym->end); memcpy(sym->name, name, namelen); return sym; } void symbol__delete(struct symbol *sym) { free(((void *)sym) - symbol_conf.priv_size); } void symbols__delete(struct rb_root *symbols) { struct symbol *pos; struct rb_node *next = rb_first(symbols); while (next) { pos = rb_entry(next, struct symbol, rb_node); next = rb_next(&pos->rb_node); rb_erase(&pos->rb_node, symbols); symbol__delete(pos); } } void symbols__insert(struct rb_root *symbols, struct symbol *sym) { struct rb_node **p = &symbols->rb_node; struct rb_node *parent = NULL; const u64 ip = sym->start; struct symbol *s; while (*p != NULL) { parent = *p; s = rb_entry(parent, struct symbol, rb_node); if (ip < s->start) p = &(*p)->rb_left; else p = &(*p)->rb_right; } rb_link_node(&sym->rb_node, parent, p); rb_insert_color(&sym->rb_node, symbols); } static struct symbol *symbols__find(struct rb_root *symbols, u64 ip) { struct rb_node *n; if (symbols == NULL) return NULL; n = symbols->rb_node; while (n) { struct symbol *s = rb_entry(n, struct symbol, rb_node); if (ip < s->start) n = n->rb_left; else if (ip >= s->end) n = n->rb_right; else return s; } return NULL; } static struct symbol *symbols__first(struct rb_root *symbols) { struct rb_node *n = rb_first(symbols); if (n) return rb_entry(n, struct symbol, rb_node); return NULL; } static struct symbol *symbols__next(struct symbol *sym) { struct rb_node *n = rb_next(&sym->rb_node); if (n) return rb_entry(n, struct symbol, rb_node); return NULL; } static void symbols__insert_by_name(struct rb_root *symbols, struct symbol *sym) { struct rb_node **p = &symbols->rb_node; struct rb_node *parent = NULL; struct symbol_name_rb_node *symn, *s; symn = container_of(sym, struct symbol_name_rb_node, sym); while (*p != NULL) { parent = *p; s = rb_entry(parent, struct symbol_name_rb_node, rb_node); if (strcmp(sym->name, s->sym.name) < 0) p = &(*p)->rb_left; else p = &(*p)->rb_right; } rb_link_node(&symn->rb_node, parent, p); rb_insert_color(&symn->rb_node, symbols); } static void symbols__sort_by_name(struct rb_root *symbols, struct rb_root *source) { struct rb_node *nd; for (nd = rb_first(source); nd; nd = rb_next(nd)) { struct symbol *pos = rb_entry(nd, struct symbol, rb_node); symbols__insert_by_name(symbols, pos); } } static struct symbol *symbols__find_by_name(struct rb_root *symbols, const char *name) { struct rb_node *n; struct symbol_name_rb_node *s = NULL; if (symbols == NULL) return NULL; n = symbols->rb_node; while (n) { int cmp; s = rb_entry(n, struct symbol_name_rb_node, rb_node); cmp = arch__compare_symbol_names(name, s->sym.name); if (cmp < 0) n = n->rb_left; else if (cmp > 0) n = n->rb_right; else break; } if (n == NULL) return NULL; /* return first symbol that has same name (if any) */ for (n = rb_prev(n); n; n = rb_prev(n)) { struct symbol_name_rb_node *tmp; tmp = rb_entry(n, struct symbol_name_rb_node, rb_node); if (arch__compare_symbol_names(tmp->sym.name, s->sym.name)) break; s = tmp; } return &s->sym; } void dso__reset_find_symbol_cache(struct dso *dso) { enum map_type type; for (type = MAP__FUNCTION; type <= MAP__VARIABLE; ++type) { dso->last_find_result[type].addr = 0; dso->last_find_result[type].symbol = NULL; } } struct symbol *dso__find_symbol(struct dso *dso, enum map_type type, u64 addr) { if (dso->last_find_result[type].addr != addr) { dso->last_find_result[type].addr = addr; dso->last_find_result[type].symbol = symbols__find(&dso->symbols[type], addr); } return dso->last_find_result[type].symbol; } struct symbol *dso__first_symbol(struct dso *dso, enum map_type type) { return symbols__first(&dso->symbols[type]); } struct symbol *dso__next_symbol(struct symbol *sym) { return symbols__next(sym); } struct symbol *symbol__next_by_name(struct symbol *sym) { struct symbol_name_rb_node *s = container_of(sym, struct symbol_name_rb_node, sym); struct rb_node *n = rb_next(&s->rb_node); return n ? &rb_entry(n, struct symbol_name_rb_node, rb_node)->sym : NULL; } /* * Teturns first symbol that matched with @name. */ struct symbol *dso__find_symbol_by_name(struct dso *dso, enum map_type type, const char *name) { return symbols__find_by_name(&dso->symbol_names[type], name); } void dso__sort_by_name(struct dso *dso, enum map_type type) { dso__set_sorted_by_name(dso, type); return symbols__sort_by_name(&dso->symbol_names[type], &dso->symbols[type]); } int modules__parse(const char *filename, void *arg, int (*process_module)(void *arg, const char *name, u64 start)) { char *line = NULL; size_t n; FILE *file; int err = 0; file = fopen(filename, "r"); if (file == NULL) return -1; while (1) { char name[PATH_MAX]; u64 start; char *sep; ssize_t line_len; line_len = getline(&line, &n, file); if (line_len < 0) { if (feof(file)) break; err = -1; goto out; } if (!line) { err = -1; goto out; } line[--line_len] = '\0'; /* \n */ sep = strrchr(line, 'x'); if (sep == NULL) continue; hex2u64(sep + 1, &start); sep = strchr(line, ' '); if (sep == NULL) continue; *sep = '\0'; scnprintf(name, sizeof(name), "[%s]", line); err = process_module(arg, name, start); if (err) break; } out: free(line); fclose(file); return err; } struct process_kallsyms_args { struct map *map; struct dso *dso; }; /* * These are symbols in the kernel image, so make sure that * sym is from a kernel DSO. */ bool symbol__is_idle(struct symbol *sym) { const char * const idle_symbols[] = { "cpu_idle", "cpu_startup_entry", "intel_idle", "default_idle", "native_safe_halt", "enter_idle", "exit_idle", "mwait_idle", "mwait_idle_with_hints", "poll_idle", "ppc64_runlatch_off", "pseries_dedicated_idle_sleep", NULL }; int i; if (!sym) return false; for (i = 0; idle_symbols[i]; i++) { if (!strcmp(idle_symbols[i], sym->name)) return true; } return false; } static int map__process_kallsym_symbol(void *arg, const char *name, char type, u64 start) { struct symbol *sym; struct process_kallsyms_args *a = arg; struct rb_root *root = &a->dso->symbols[a->map->type]; if (!symbol_type__is_a(type, a->map->type)) return 0; /* * module symbols are not sorted so we add all * symbols, setting length to 0, and rely on * symbols__fixup_end() to fix it up. */ sym = symbol__new(start, 0, kallsyms2elf_binding(type), name); if (sym == NULL) return -ENOMEM; /* * We will pass the symbols to the filter later, in * map__split_kallsyms, when we have split the maps per module */ symbols__insert(root, sym); return 0; } /* * Loads the function entries in /proc/kallsyms into kernel_map->dso, * so that we can in the next step set the symbol ->end address and then * call kernel_maps__split_kallsyms. */ static int dso__load_all_kallsyms(struct dso *dso, const char *filename, struct map *map) { struct process_kallsyms_args args = { .map = map, .dso = dso, }; return kallsyms__parse(filename, &args, map__process_kallsym_symbol); } static int dso__split_kallsyms_for_kcore(struct dso *dso, struct map *map, symbol_filter_t filter) { struct map_groups *kmaps = map__kmaps(map); struct map *curr_map; struct symbol *pos; int count = 0; struct rb_root old_root = dso->symbols[map->type]; struct rb_root *root = &dso->symbols[map->type]; struct rb_node *next = rb_first(root); if (!kmaps) return -1; *root = RB_ROOT; while (next) { char *module; pos = rb_entry(next, struct symbol, rb_node); next = rb_next(&pos->rb_node); rb_erase_init(&pos->rb_node, &old_root); module = strchr(pos->name, '\t'); if (module) *module = '\0'; curr_map = map_groups__find(kmaps, map->type, pos->start); if (!curr_map || (filter && filter(curr_map, pos))) { symbol__delete(pos); continue; } pos->start -= curr_map->start - curr_map->pgoff; if (pos->end) pos->end -= curr_map->start - curr_map->pgoff; symbols__insert(&curr_map->dso->symbols[curr_map->type], pos); ++count; } /* Symbols have been adjusted */ dso->adjust_symbols = 1; return count; } /* * Split the symbols into maps, making sure there are no overlaps, i.e. the * kernel range is broken in several maps, named [kernel].N, as we don't have * the original ELF section names vmlinux have. */ static int dso__split_kallsyms(struct dso *dso, struct map *map, u64 delta, symbol_filter_t filter) { struct map_groups *kmaps = map__kmaps(map); struct machine *machine; struct map *curr_map = map; struct symbol *pos; int count = 0, moved = 0; struct rb_root *root = &dso->symbols[map->type]; struct rb_node *next = rb_first(root); int kernel_range = 0; if (!kmaps) return -1; machine = kmaps->machine; while (next) { char *module; pos = rb_entry(next, struct symbol, rb_node); next = rb_next(&pos->rb_node); module = strchr(pos->name, '\t'); if (module) { if (!symbol_conf.use_modules) goto discard_symbol; *module++ = '\0'; if (strcmp(curr_map->dso->short_name, module)) { if (curr_map != map && dso->kernel == DSO_TYPE_GUEST_KERNEL && machine__is_default_guest(machine)) { /* * We assume all symbols of a module are * continuous in * kallsyms, so curr_map * points to a module and all its * symbols are in its kmap. Mark it as * loaded. */ dso__set_loaded(curr_map->dso, curr_map->type); } curr_map = map_groups__find_by_name(kmaps, map->type, module); if (curr_map == NULL) { pr_debug("%s/proc/{kallsyms,modules} " "inconsistency while looking " "for \"%s\" module!\n", machine->root_dir, module); curr_map = map; goto discard_symbol; } if (curr_map->dso->loaded && !machine__is_default_guest(machine)) goto discard_symbol; } /* * So that we look just like we get from .ko files, * i.e. not prelinked, relative to map->start. */ pos->start = curr_map->map_ip(curr_map, pos->start); pos->end = curr_map->map_ip(curr_map, pos->end); } else if (curr_map != map) { char dso_name[PATH_MAX]; struct dso *ndso; if (delta) { /* Kernel was relocated at boot time */ pos->start -= delta; pos->end -= delta; } if (count == 0) { curr_map = map; goto filter_symbol; } if (dso->kernel == DSO_TYPE_GUEST_KERNEL) snprintf(dso_name, sizeof(dso_name), "[guest.kernel].%d", kernel_range++); else snprintf(dso_name, sizeof(dso_name), "[kernel].%d", kernel_range++); ndso = dso__new(dso_name); if (ndso == NULL) return -1; ndso->kernel = dso->kernel; curr_map = map__new2(pos->start, ndso, map->type); if (curr_map == NULL) { dso__put(ndso); return -1; } curr_map->map_ip = curr_map->unmap_ip = identity__map_ip; map_groups__insert(kmaps, curr_map); ++kernel_range; } else if (delta) { /* Kernel was relocated at boot time */ pos->start -= delta; pos->end -= delta; } filter_symbol: if (filter && filter(curr_map, pos)) { discard_symbol: rb_erase(&pos->rb_node, root); symbol__delete(pos); } else { if (curr_map != map) { rb_erase(&pos->rb_node, root); symbols__insert(&curr_map->dso->symbols[curr_map->type], pos); ++moved; } else ++count; } } if (curr_map != map && dso->kernel == DSO_TYPE_GUEST_KERNEL && machine__is_default_guest(kmaps->machine)) { dso__set_loaded(curr_map->dso, curr_map->type); } return count + moved; } bool symbol__restricted_filename(const char *filename, const char *restricted_filename) { bool restricted = false; if (symbol_conf.kptr_restrict) { char *r = realpath(filename, NULL); if (r != NULL) { restricted = strcmp(r, restricted_filename) == 0; free(r); return restricted; } } return restricted; } struct module_info { struct rb_node rb_node; char *name; u64 start; }; static void add_module(struct module_info *mi, struct rb_root *modules) { struct rb_node **p = &modules->rb_node; struct rb_node *parent = NULL; struct module_info *m; while (*p != NULL) { parent = *p; m = rb_entry(parent, struct module_info, rb_node); if (strcmp(mi->name, m->name) < 0) p = &(*p)->rb_left; else p = &(*p)->rb_right; } rb_link_node(&mi->rb_node, parent, p); rb_insert_color(&mi->rb_node, modules); } static void delete_modules(struct rb_root *modules) { struct module_info *mi; struct rb_node *next = rb_first(modules); while (next) { mi = rb_entry(next, struct module_info, rb_node); next = rb_next(&mi->rb_node); rb_erase(&mi->rb_node, modules); zfree(&mi->name); free(mi); } } static struct module_info *find_module(const char *name, struct rb_root *modules) { struct rb_node *n = modules->rb_node; while (n) { struct module_info *m; int cmp; m = rb_entry(n, struct module_info, rb_node); cmp = strcmp(name, m->name); if (cmp < 0) n = n->rb_left; else if (cmp > 0) n = n->rb_right; else return m; } return NULL; } static int __read_proc_modules(void *arg, const char *name, u64 start) { struct rb_root *modules = arg; struct module_info *mi; mi = zalloc(sizeof(struct module_info)); if (!mi) return -ENOMEM; mi->name = strdup(name); mi->start = start; if (!mi->name) { free(mi); return -ENOMEM; } add_module(mi, modules); return 0; } static int read_proc_modules(const char *filename, struct rb_root *modules) { if (symbol__restricted_filename(filename, "/proc/modules")) return -1; if (modules__parse(filename, modules, __read_proc_modules)) { delete_modules(modules); return -1; } return 0; } int compare_proc_modules(const char *from, const char *to) { struct rb_root from_modules = RB_ROOT; struct rb_root to_modules = RB_ROOT; struct rb_node *from_node, *to_node; struct module_info *from_m, *to_m; int ret = -1; if (read_proc_modules(from, &from_modules)) return -1; if (read_proc_modules(to, &to_modules)) goto out_delete_from; from_node = rb_first(&from_modules); to_node = rb_first(&to_modules); while (from_node) { if (!to_node) break; from_m = rb_entry(from_node, struct module_info, rb_node); to_m = rb_entry(to_node, struct module_info, rb_node); if (from_m->start != to_m->start || strcmp(from_m->name, to_m->name)) break; from_node = rb_next(from_node); to_node = rb_next(to_node); } if (!from_node && !to_node) ret = 0; delete_modules(&to_modules); out_delete_from: delete_modules(&from_modules); return ret; } static int do_validate_kcore_modules(const char *filename, struct map *map, struct map_groups *kmaps) { struct rb_root modules = RB_ROOT; struct map *old_map; int err; err = read_proc_modules(filename, &modules); if (err) return err; old_map = map_groups__first(kmaps, map->type); while (old_map) { struct map *next = map_groups__next(old_map); struct module_info *mi; if (old_map == map || old_map->start == map->start) { /* The kernel map */ old_map = next; continue; } /* Module must be in memory at the same address */ mi = find_module(old_map->dso->short_name, &modules); if (!mi || mi->start != old_map->start) { err = -EINVAL; goto out; } old_map = next; } out: delete_modules(&modules); return err; } /* * If kallsyms is referenced by name then we look for filename in the same * directory. */ static bool filename_from_kallsyms_filename(char *filename, const char *base_name, const char *kallsyms_filename) { char *name; strcpy(filename, kallsyms_filename); name = strrchr(filename, '/'); if (!name) return false; name += 1; if (!strcmp(name, "kallsyms")) { strcpy(name, base_name); return true; } return false; } static int validate_kcore_modules(const char *kallsyms_filename, struct map *map) { struct map_groups *kmaps = map__kmaps(map); char modules_filename[PATH_MAX]; if (!kmaps) return -EINVAL; if (!filename_from_kallsyms_filename(modules_filename, "modules", kallsyms_filename)) return -EINVAL; if (do_validate_kcore_modules(modules_filename, map, kmaps)) return -EINVAL; return 0; } static int validate_kcore_addresses(const char *kallsyms_filename, struct map *map) { struct kmap *kmap = map__kmap(map); if (!kmap) return -EINVAL; if (kmap->ref_reloc_sym && kmap->ref_reloc_sym->name) { u64 start; start = kallsyms__get_function_start(kallsyms_filename, kmap->ref_reloc_sym->name); if (start != kmap->ref_reloc_sym->addr) return -EINVAL; } return validate_kcore_modules(kallsyms_filename, map); } struct kcore_mapfn_data { struct dso *dso; enum map_type type; struct list_head maps; }; static int kcore_mapfn(u64 start, u64 len, u64 pgoff, void *data) { struct kcore_mapfn_data *md = data; struct map *map; map = map__new2(start, md->dso, md->type); if (map == NULL) return -ENOMEM; map->end = map->start + len; map->pgoff = pgoff; list_add(&map->node, &md->maps); return 0; } static int dso__load_kcore(struct dso *dso, struct map *map, const char *kallsyms_filename) { struct map_groups *kmaps = map__kmaps(map); struct machine *machine; struct kcore_mapfn_data md; struct map *old_map, *new_map, *replacement_map = NULL; bool is_64_bit; int err, fd; char kcore_filename[PATH_MAX]; struct symbol *sym; if (!kmaps) return -EINVAL; machine = kmaps->machine; /* This function requires that the map is the kernel map */ if (map != machine->vmlinux_maps[map->type]) return -EINVAL; if (!filename_from_kallsyms_filename(kcore_filename, "kcore", kallsyms_filename)) return -EINVAL; /* Modules and kernel must be present at their original addresses */ if (validate_kcore_addresses(kallsyms_filename, map)) return -EINVAL; md.dso = dso; md.type = map->type; INIT_LIST_HEAD(&md.maps); fd = open(kcore_filename, O_RDONLY); if (fd < 0) { pr_debug("Failed to open %s. Note /proc/kcore requires CAP_SYS_RAWIO capability to access.\n", kcore_filename); return -EINVAL; } /* Read new maps into temporary lists */ err = file__read_maps(fd, md.type == MAP__FUNCTION, kcore_mapfn, &md, &is_64_bit); if (err) goto out_err; dso->is_64_bit = is_64_bit; if (list_empty(&md.maps)) { err = -EINVAL; goto out_err; } /* Remove old maps */ old_map = map_groups__first(kmaps, map->type); while (old_map) { struct map *next = map_groups__next(old_map); if (old_map != map) map_groups__remove(kmaps, old_map); old_map = next; } /* Find the kernel map using the first symbol */ sym = dso__first_symbol(dso, map->type); list_for_each_entry(new_map, &md.maps, node) { if (sym && sym->start >= new_map->start && sym->start < new_map->end) { replacement_map = new_map; break; } } if (!replacement_map) replacement_map = list_entry(md.maps.next, struct map, node); /* Add new maps */ while (!list_empty(&md.maps)) { new_map = list_entry(md.maps.next, struct map, node); list_del_init(&new_map->node); if (new_map == replacement_map) { map->start = new_map->start; map->end = new_map->end; map->pgoff = new_map->pgoff; map->map_ip = new_map->map_ip; map->unmap_ip = new_map->unmap_ip; /* Ensure maps are correctly ordered */ map__get(map); map_groups__remove(kmaps, map); map_groups__insert(kmaps, map); map__put(map); } else { map_groups__insert(kmaps, new_map); } map__put(new_map); } /* * Set the data type and long name so that kcore can be read via * dso__data_read_addr(). */ if (dso->kernel == DSO_TYPE_GUEST_KERNEL) dso->binary_type = DSO_BINARY_TYPE__GUEST_KCORE; else dso->binary_type = DSO_BINARY_TYPE__KCORE; dso__set_long_name(dso, strdup(kcore_filename), true); close(fd); if (map->type == MAP__FUNCTION) pr_debug("Using %s for kernel object code\n", kcore_filename); else pr_debug("Using %s for kernel data\n", kcore_filename); return 0; out_err: while (!list_empty(&md.maps)) { map = list_entry(md.maps.next, struct map, node); list_del_init(&map->node); map__put(map); } close(fd); return -EINVAL; } /* * If the kernel is relocated at boot time, kallsyms won't match. Compute the * delta based on the relocation reference symbol. */ static int kallsyms__delta(struct map *map, const char *filename, u64 *delta) { struct kmap *kmap = map__kmap(map); u64 addr; if (!kmap) return -1; if (!kmap->ref_reloc_sym || !kmap->ref_reloc_sym->name) return 0; addr = kallsyms__get_function_start(filename, kmap->ref_reloc_sym->name); if (!addr) return -1; *delta = addr - kmap->ref_reloc_sym->addr; return 0; } int dso__load_kallsyms(struct dso *dso, const char *filename, struct map *map, symbol_filter_t filter) { u64 delta = 0; if (symbol__restricted_filename(filename, "/proc/kallsyms")) return -1; if (dso__load_all_kallsyms(dso, filename, map) < 0) return -1; if (kallsyms__delta(map, filename, &delta)) return -1; symbols__fixup_duplicate(&dso->symbols[map->type]); symbols__fixup_end(&dso->symbols[map->type]); if (dso->kernel == DSO_TYPE_GUEST_KERNEL) dso->symtab_type = DSO_BINARY_TYPE__GUEST_KALLSYMS; else dso->symtab_type = DSO_BINARY_TYPE__KALLSYMS; if (!dso__load_kcore(dso, map, filename)) return dso__split_kallsyms_for_kcore(dso, map, filter); else return dso__split_kallsyms(dso, map, delta, filter); } static int dso__load_perf_map(struct dso *dso, struct map *map, symbol_filter_t filter) { char *line = NULL; size_t n; FILE *file; int nr_syms = 0; file = fopen(dso->long_name, "r"); if (file == NULL) goto out_failure; while (!feof(file)) { u64 start, size; struct symbol *sym; int line_len, len; line_len = getline(&line, &n, file); if (line_len < 0) break; if (!line) goto out_failure; line[--line_len] = '\0'; /* \n */ len = hex2u64(line, &start); len++; if (len + 2 >= line_len) continue; len += hex2u64(line + len, &size); len++; if (len + 2 >= line_len) continue; sym = symbol__new(start, size, STB_GLOBAL, line + len); if (sym == NULL) goto out_delete_line; if (filter && filter(map, sym)) symbol__delete(sym); else { symbols__insert(&dso->symbols[map->type], sym); nr_syms++; } } free(line); fclose(file); return nr_syms; out_delete_line: free(line); out_failure: return -1; } static bool dso__is_compatible_symtab_type(struct dso *dso, bool kmod, enum dso_binary_type type) { switch (type) { case DSO_BINARY_TYPE__JAVA_JIT: case DSO_BINARY_TYPE__DEBUGLINK: case DSO_BINARY_TYPE__SYSTEM_PATH_DSO: case DSO_BINARY_TYPE__FEDORA_DEBUGINFO: case DSO_BINARY_TYPE__UBUNTU_DEBUGINFO: case DSO_BINARY_TYPE__BUILDID_DEBUGINFO: case DSO_BINARY_TYPE__OPENEMBEDDED_DEBUGINFO: return !kmod && dso->kernel == DSO_TYPE_USER; case DSO_BINARY_TYPE__KALLSYMS: case DSO_BINARY_TYPE__VMLINUX: case DSO_BINARY_TYPE__KCORE: return dso->kernel == DSO_TYPE_KERNEL; case DSO_BINARY_TYPE__GUEST_KALLSYMS: case DSO_BINARY_TYPE__GUEST_VMLINUX: case DSO_BINARY_TYPE__GUEST_KCORE: return dso->kernel == DSO_TYPE_GUEST_KERNEL; case DSO_BINARY_TYPE__GUEST_KMODULE: case DSO_BINARY_TYPE__GUEST_KMODULE_COMP: case DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE: case DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP: /* * kernel modules know their symtab type - it's set when * creating a module dso in machine__findnew_module_map(). */ return kmod && dso->symtab_type == type; case DSO_BINARY_TYPE__BUILD_ID_CACHE: return true; case DSO_BINARY_TYPE__NOT_FOUND: default: return false; } } int dso__load(struct dso *dso, struct map *map, symbol_filter_t filter) { char *name; int ret = -1; u_int i; struct machine *machine; char *root_dir = (char *) ""; int ss_pos = 0; struct symsrc ss_[2]; struct symsrc *syms_ss = NULL, *runtime_ss = NULL; bool kmod; unsigned char build_id[BUILD_ID_SIZE]; pthread_mutex_lock(&dso->lock); /* check again under the dso->lock */ if (dso__loaded(dso, map->type)) { ret = 1; goto out; } if (dso->kernel) { if (dso->kernel == DSO_TYPE_KERNEL) ret = dso__load_kernel_sym(dso, map, filter); else if (dso->kernel == DSO_TYPE_GUEST_KERNEL) ret = dso__load_guest_kernel_sym(dso, map, filter); goto out; } if (map->groups && map->groups->machine) machine = map->groups->machine; else machine = NULL; dso->adjust_symbols = 0; if (strncmp(dso->name, "/tmp/perf-", 10) == 0) { struct stat st; if (lstat(dso->name, &st) < 0) goto out; if (!symbol_conf.force && st.st_uid && (st.st_uid != geteuid())) { pr_warning("File %s not owned by current user or root, " "ignoring it (use -f to override).\n", dso->name); goto out; } ret = dso__load_perf_map(dso, map, filter); dso->symtab_type = ret > 0 ? DSO_BINARY_TYPE__JAVA_JIT : DSO_BINARY_TYPE__NOT_FOUND; goto out; } if (machine) root_dir = machine->root_dir; name = malloc(PATH_MAX); if (!name) goto out; kmod = dso->symtab_type == DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE || dso->symtab_type == DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP || dso->symtab_type == DSO_BINARY_TYPE__GUEST_KMODULE || dso->symtab_type == DSO_BINARY_TYPE__GUEST_KMODULE_COMP; /* * Read the build id if possible. This is required for * DSO_BINARY_TYPE__BUILDID_DEBUGINFO to work */ if (is_regular_file(name) && filename__read_build_id(dso->long_name, build_id, BUILD_ID_SIZE) > 0) dso__set_build_id(dso, build_id); /* * Iterate over candidate debug images. * Keep track of "interesting" ones (those which have a symtab, dynsym, * and/or opd section) for processing. */ for (i = 0; i < DSO_BINARY_TYPE__SYMTAB_CNT; i++) { struct symsrc *ss = &ss_[ss_pos]; bool next_slot = false; enum dso_binary_type symtab_type = binary_type_symtab[i]; if (!dso__is_compatible_symtab_type(dso, kmod, symtab_type)) continue; if (dso__read_binary_type_filename(dso, symtab_type, root_dir, name, PATH_MAX)) continue; if (!is_regular_file(name)) continue; /* Name is now the name of the next image to try */ if (symsrc__init(ss, dso, name, symtab_type) < 0) continue; if (!syms_ss && symsrc__has_symtab(ss)) { syms_ss = ss; next_slot = true; if (!dso->symsrc_filename) dso->symsrc_filename = strdup(name); } if (!runtime_ss && symsrc__possibly_runtime(ss)) { runtime_ss = ss; next_slot = true; } if (next_slot) { ss_pos++; if (syms_ss && runtime_ss) break; } else { symsrc__destroy(ss); } } if (!runtime_ss && !syms_ss) goto out_free; if (runtime_ss && !syms_ss) { syms_ss = runtime_ss; } /* We'll have to hope for the best */ if (!runtime_ss && syms_ss) runtime_ss = syms_ss; if (syms_ss && syms_ss->type == DSO_BINARY_TYPE__BUILD_ID_CACHE) if (dso__build_id_is_kmod(dso, name, PATH_MAX)) kmod = true; if (syms_ss) ret = dso__load_sym(dso, map, syms_ss, runtime_ss, filter, kmod); else ret = -1; if (ret > 0) { int nr_plt; nr_plt = dso__synthesize_plt_symbols(dso, runtime_ss, map, filter); if (nr_plt > 0) ret += nr_plt; } for (; ss_pos > 0; ss_pos--) symsrc__destroy(&ss_[ss_pos - 1]); out_free: free(name); if (ret < 0 && strstr(dso->name, " (deleted)") != NULL) ret = 0; out: dso__set_loaded(dso, map->type); pthread_mutex_unlock(&dso->lock); return ret; } struct map *map_groups__find_by_name(struct map_groups *mg, enum map_type type, const char *name) { struct maps *maps = &mg->maps[type]; struct map *map; pthread_rwlock_rdlock(&maps->lock); for (map = maps__first(maps); map; map = map__next(map)) { if (map->dso && strcmp(map->dso->short_name, name) == 0) goto out_unlock; } map = NULL; out_unlock: pthread_rwlock_unlock(&maps->lock); return map; } int dso__load_vmlinux(struct dso *dso, struct map *map, const char *vmlinux, bool vmlinux_allocated, symbol_filter_t filter) { int err = -1; struct symsrc ss; char symfs_vmlinux[PATH_MAX]; enum dso_binary_type symtab_type; if (vmlinux[0] == '/') snprintf(symfs_vmlinux, sizeof(symfs_vmlinux), "%s", vmlinux); else symbol__join_symfs(symfs_vmlinux, vmlinux); if (dso->kernel == DSO_TYPE_GUEST_KERNEL) symtab_type = DSO_BINARY_TYPE__GUEST_VMLINUX; else symtab_type = DSO_BINARY_TYPE__VMLINUX; if (symsrc__init(&ss, dso, symfs_vmlinux, symtab_type)) return -1; err = dso__load_sym(dso, map, &ss, &ss, filter, 0); symsrc__destroy(&ss); if (err > 0) { if (dso->kernel == DSO_TYPE_GUEST_KERNEL) dso->binary_type = DSO_BINARY_TYPE__GUEST_VMLINUX; else dso->binary_type = DSO_BINARY_TYPE__VMLINUX; dso__set_long_name(dso, vmlinux, vmlinux_allocated); dso__set_loaded(dso, map->type); pr_debug("Using %s for symbols\n", symfs_vmlinux); } return err; } int dso__load_vmlinux_path(struct dso *dso, struct map *map, symbol_filter_t filter) { int i, err = 0; char *filename = NULL; pr_debug("Looking at the vmlinux_path (%d entries long)\n", vmlinux_path__nr_entries + 1); for (i = 0; i < vmlinux_path__nr_entries; ++i) { err = dso__load_vmlinux(dso, map, vmlinux_path[i], false, filter); if (err > 0) goto out; } if (!symbol_conf.ignore_vmlinux_buildid) filename = dso__build_id_filename(dso, NULL, 0); if (filename != NULL) { err = dso__load_vmlinux(dso, map, filename, true, filter); if (err > 0) goto out; free(filename); } out: return err; } static int find_matching_kcore(struct map *map, char *dir, size_t dir_sz) { char kallsyms_filename[PATH_MAX]; struct dirent *dent; int ret = -1; DIR *d; d = opendir(dir); if (!d) return -1; while (1) { dent = readdir(d); if (!dent) break; if (dent->d_type != DT_DIR) continue; scnprintf(kallsyms_filename, sizeof(kallsyms_filename), "%s/%s/kallsyms", dir, dent->d_name); if (!validate_kcore_addresses(kallsyms_filename, map)) { strlcpy(dir, kallsyms_filename, dir_sz); ret = 0; break; } } closedir(d); return ret; } static char *dso__find_kallsyms(struct dso *dso, struct map *map) { u8 host_build_id[BUILD_ID_SIZE]; char sbuild_id[BUILD_ID_SIZE * 2 + 1]; bool is_host = false; char path[PATH_MAX]; if (!dso->has_build_id) { /* * Last resort, if we don't have a build-id and couldn't find * any vmlinux file, try the running kernel kallsyms table. */ goto proc_kallsyms; } if (sysfs__read_build_id("/sys/kernel/notes", host_build_id, sizeof(host_build_id)) == 0) is_host = dso__build_id_equal(dso, host_build_id); build_id__sprintf(dso->build_id, sizeof(dso->build_id), sbuild_id); scnprintf(path, sizeof(path), "%s/[kernel.kcore]/%s", buildid_dir, sbuild_id); /* Use /proc/kallsyms if possible */ if (is_host) { DIR *d; int fd; /* If no cached kcore go with /proc/kallsyms */ d = opendir(path); if (!d) goto proc_kallsyms; closedir(d); /* * Do not check the build-id cache, until we know we cannot use * /proc/kcore. */ fd = open("/proc/kcore", O_RDONLY); if (fd != -1) { close(fd); /* If module maps match go with /proc/kallsyms */ if (!validate_kcore_addresses("/proc/kallsyms", map)) goto proc_kallsyms; } /* Find kallsyms in build-id cache with kcore */ if (!find_matching_kcore(map, path, sizeof(path))) return strdup(path); goto proc_kallsyms; } /* Find kallsyms in build-id cache with kcore */ if (!find_matching_kcore(map, path, sizeof(path))) return strdup(path); scnprintf(path, sizeof(path), "%s/[kernel.kallsyms]/%s", buildid_dir, sbuild_id); if (access(path, F_OK)) { pr_err("No kallsyms or vmlinux with build-id %s was found\n", sbuild_id); return NULL; } return strdup(path); proc_kallsyms: return strdup("/proc/kallsyms"); } static int dso__load_kernel_sym(struct dso *dso, struct map *map, symbol_filter_t filter) { int err; const char *kallsyms_filename = NULL; char *kallsyms_allocated_filename = NULL; /* * Step 1: if the user specified a kallsyms or vmlinux filename, use * it and only it, reporting errors to the user if it cannot be used. * * For instance, try to analyse an ARM perf.data file _without_ a * build-id, or if the user specifies the wrong path to the right * vmlinux file, obviously we can't fallback to another vmlinux (a * x86_86 one, on the machine where analysis is being performed, say), * or worse, /proc/kallsyms. * * If the specified file _has_ a build-id and there is a build-id * section in the perf.data file, we will still do the expected * validation in dso__load_vmlinux and will bail out if they don't * match. */ if (symbol_conf.kallsyms_name != NULL) { kallsyms_filename = symbol_conf.kallsyms_name; goto do_kallsyms; } if (!symbol_conf.ignore_vmlinux && symbol_conf.vmlinux_name != NULL) { return dso__load_vmlinux(dso, map, symbol_conf.vmlinux_name, false, filter); } if (!symbol_conf.ignore_vmlinux && vmlinux_path != NULL) { err = dso__load_vmlinux_path(dso, map, filter); if (err > 0) return err; } /* do not try local files if a symfs was given */ if (symbol_conf.symfs[0] != 0) return -1; kallsyms_allocated_filename = dso__find_kallsyms(dso, map); if (!kallsyms_allocated_filename) return -1; kallsyms_filename = kallsyms_allocated_filename; do_kallsyms: err = dso__load_kallsyms(dso, kallsyms_filename, map, filter); if (err > 0) pr_debug("Using %s for symbols\n", kallsyms_filename); free(kallsyms_allocated_filename); if (err > 0 && !dso__is_kcore(dso)) { dso->binary_type = DSO_BINARY_TYPE__KALLSYMS; dso__set_long_name(dso, "[kernel.kallsyms]", false); map__fixup_start(map); map__fixup_end(map); } return err; } static int dso__load_guest_kernel_sym(struct dso *dso, struct map *map, symbol_filter_t filter) { int err; const char *kallsyms_filename = NULL; struct machine *machine; char path[PATH_MAX]; if (!map->groups) { pr_debug("Guest kernel map hasn't the point to groups\n"); return -1; } machine = map->groups->machine; if (machine__is_default_guest(machine)) { /* * if the user specified a vmlinux filename, use it and only * it, reporting errors to the user if it cannot be used. * Or use file guest_kallsyms inputted by user on commandline */ if (symbol_conf.default_guest_vmlinux_name != NULL) { err = dso__load_vmlinux(dso, map, symbol_conf.default_guest_vmlinux_name, false, filter); return err; } kallsyms_filename = symbol_conf.default_guest_kallsyms; if (!kallsyms_filename) return -1; } else { sprintf(path, "%s/proc/kallsyms", machine->root_dir); kallsyms_filename = path; } err = dso__load_kallsyms(dso, kallsyms_filename, map, filter); if (err > 0) pr_debug("Using %s for symbols\n", kallsyms_filename); if (err > 0 && !dso__is_kcore(dso)) { dso->binary_type = DSO_BINARY_TYPE__GUEST_KALLSYMS; machine__mmap_name(machine, path, sizeof(path)); dso__set_long_name(dso, strdup(path), true); map__fixup_start(map); map__fixup_end(map); } return err; } static void vmlinux_path__exit(void) { while (--vmlinux_path__nr_entries >= 0) zfree(&vmlinux_path[vmlinux_path__nr_entries]); vmlinux_path__nr_entries = 0; zfree(&vmlinux_path); } static const char * const vmlinux_paths[] = { "vmlinux", "/boot/vmlinux" }; static const char * const vmlinux_paths_upd[] = { "/boot/vmlinux-%s", "/usr/lib/debug/boot/vmlinux-%s", "/lib/modules/%s/build/vmlinux", "/usr/lib/debug/lib/modules/%s/vmlinux", "/usr/lib/debug/boot/vmlinux-%s.debug" }; static int vmlinux_path__add(const char *new_entry) { vmlinux_path[vmlinux_path__nr_entries] = strdup(new_entry); if (vmlinux_path[vmlinux_path__nr_entries] == NULL) return -1; ++vmlinux_path__nr_entries; return 0; } static int vmlinux_path__init(struct perf_env *env) { struct utsname uts; char bf[PATH_MAX]; char *kernel_version; unsigned int i; vmlinux_path = malloc(sizeof(char *) * (ARRAY_SIZE(vmlinux_paths) + ARRAY_SIZE(vmlinux_paths_upd))); if (vmlinux_path == NULL) return -1; for (i = 0; i < ARRAY_SIZE(vmlinux_paths); i++) if (vmlinux_path__add(vmlinux_paths[i]) < 0) goto out_fail; /* only try kernel version if no symfs was given */ if (symbol_conf.symfs[0] != 0) return 0; if (env) { kernel_version = env->os_release; } else { if (uname(&uts) < 0) goto out_fail; kernel_version = uts.release; } for (i = 0; i < ARRAY_SIZE(vmlinux_paths_upd); i++) { snprintf(bf, sizeof(bf), vmlinux_paths_upd[i], kernel_version); if (vmlinux_path__add(bf) < 0) goto out_fail; } return 0; out_fail: vmlinux_path__exit(); return -1; } int setup_list(struct strlist **list, const char *list_str, const char *list_name) { if (list_str == NULL) return 0; *list = strlist__new(list_str, NULL); if (!*list) { pr_err("problems parsing %s list\n", list_name); return -1; } symbol_conf.has_filter = true; return 0; } int setup_intlist(struct intlist **list, const char *list_str, const char *list_name) { if (list_str == NULL) return 0; *list = intlist__new(list_str); if (!*list) { pr_err("problems parsing %s list\n", list_name); return -1; } return 0; } static bool symbol__read_kptr_restrict(void) { bool value = false; if (geteuid() != 0) { FILE *fp = fopen("/proc/sys/kernel/kptr_restrict", "r"); if (fp != NULL) { char line[8]; if (fgets(line, sizeof(line), fp) != NULL) value = atoi(line) != 0; fclose(fp); } } return value; } int symbol__init(struct perf_env *env) { const char *symfs; if (symbol_conf.initialized) return 0; symbol_conf.priv_size = PERF_ALIGN(symbol_conf.priv_size, sizeof(u64)); symbol__elf_init(); if (symbol_conf.sort_by_name) symbol_conf.priv_size += (sizeof(struct symbol_name_rb_node) - sizeof(struct symbol)); if (symbol_conf.try_vmlinux_path && vmlinux_path__init(env) < 0) return -1; if (symbol_conf.field_sep && *symbol_conf.field_sep == '.') { pr_err("'.' is the only non valid --field-separator argument\n"); return -1; } if (setup_list(&symbol_conf.dso_list, symbol_conf.dso_list_str, "dso") < 0) return -1; if (setup_list(&symbol_conf.comm_list, symbol_conf.comm_list_str, "comm") < 0) goto out_free_dso_list; if (setup_intlist(&symbol_conf.pid_list, symbol_conf.pid_list_str, "pid") < 0) goto out_free_comm_list; if (setup_intlist(&symbol_conf.tid_list, symbol_conf.tid_list_str, "tid") < 0) goto out_free_pid_list; if (setup_list(&symbol_conf.sym_list, symbol_conf.sym_list_str, "symbol") < 0) goto out_free_tid_list; /* * A path to symbols of "/" is identical to "" * reset here for simplicity. */ symfs = realpath(symbol_conf.symfs, NULL); if (symfs == NULL) symfs = symbol_conf.symfs; if (strcmp(symfs, "/") == 0) symbol_conf.symfs = ""; if (symfs != symbol_conf.symfs) free((void *)symfs); symbol_conf.kptr_restrict = symbol__read_kptr_restrict(); symbol_conf.initialized = true; return 0; out_free_tid_list: intlist__delete(symbol_conf.tid_list); out_free_pid_list: intlist__delete(symbol_conf.pid_list); out_free_comm_list: strlist__delete(symbol_conf.comm_list); out_free_dso_list: strlist__delete(symbol_conf.dso_list); return -1; } void symbol__exit(void) { if (!symbol_conf.initialized) return; strlist__delete(symbol_conf.sym_list); strlist__delete(symbol_conf.dso_list); strlist__delete(symbol_conf.comm_list); intlist__delete(symbol_conf.tid_list); intlist__delete(symbol_conf.pid_list); vmlinux_path__exit(); symbol_conf.sym_list = symbol_conf.dso_list = symbol_conf.comm_list = NULL; symbol_conf.initialized = false; }