1 // SPDX-License-Identifier: GPL-2.0
7 #include <linux/capability.h>
8 #include <linux/kernel.h>
9 #include <linux/mman.h>
10 #include <linux/string.h>
11 #include <linux/time64.h>
12 #include <sys/types.h>
14 #include <sys/param.h>
22 #include "util.h" // lsdir()
28 #include "map_symbol.h"
29 #include "mem-events.h"
33 #include "namespaces.h"
36 #include <linux/ctype.h>
37 #include <linux/zalloc.h>
41 #include <symbol/kallsyms.h>
42 #include <sys/utsname.h>
44 static int dso__load_kernel_sym(struct dso *dso, struct map *map);
45 static int dso__load_guest_kernel_sym(struct dso *dso, struct map *map);
46 static bool symbol__is_idle(const char *name);
48 int vmlinux_path__nr_entries;
51 struct symbol_conf symbol_conf = {
54 .try_vmlinux_path = true,
56 .demangle_kernel = false,
57 .cumulate_callchain = true,
58 .time_quantum = 100 * NSEC_PER_MSEC, /* 100ms */
59 .show_hist_headers = true,
66 static enum dso_binary_type binary_type_symtab[] = {
67 DSO_BINARY_TYPE__KALLSYMS,
68 DSO_BINARY_TYPE__GUEST_KALLSYMS,
69 DSO_BINARY_TYPE__JAVA_JIT,
70 DSO_BINARY_TYPE__DEBUGLINK,
71 DSO_BINARY_TYPE__BUILD_ID_CACHE,
72 DSO_BINARY_TYPE__BUILD_ID_CACHE_DEBUGINFO,
73 DSO_BINARY_TYPE__FEDORA_DEBUGINFO,
74 DSO_BINARY_TYPE__UBUNTU_DEBUGINFO,
75 DSO_BINARY_TYPE__BUILDID_DEBUGINFO,
76 DSO_BINARY_TYPE__SYSTEM_PATH_DSO,
77 DSO_BINARY_TYPE__GUEST_KMODULE,
78 DSO_BINARY_TYPE__GUEST_KMODULE_COMP,
79 DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE,
80 DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP,
81 DSO_BINARY_TYPE__OPENEMBEDDED_DEBUGINFO,
82 DSO_BINARY_TYPE__MIXEDUP_UBUNTU_DEBUGINFO,
83 DSO_BINARY_TYPE__NOT_FOUND,
86 #define DSO_BINARY_TYPE__SYMTAB_CNT ARRAY_SIZE(binary_type_symtab)
88 static bool symbol_type__filter(char symbol_type)
90 symbol_type = toupper(symbol_type);
91 return symbol_type == 'T' || symbol_type == 'W' || symbol_type == 'D' || symbol_type == 'B';
94 static int prefix_underscores_count(const char *str)
96 const char *tail = str;
104 const char * __weak arch__normalize_symbol_name(const char *name)
109 int __weak arch__compare_symbol_names(const char *namea, const char *nameb)
111 return strcmp(namea, nameb);
114 int __weak arch__compare_symbol_names_n(const char *namea, const char *nameb,
117 return strncmp(namea, nameb, n);
120 int __weak arch__choose_best_symbol(struct symbol *syma,
121 struct symbol *symb __maybe_unused)
123 /* Avoid "SyS" kernel syscall aliases */
124 if (strlen(syma->name) >= 3 && !strncmp(syma->name, "SyS", 3))
126 if (strlen(syma->name) >= 10 && !strncmp(syma->name, "compat_SyS", 10))
132 static int choose_best_symbol(struct symbol *syma, struct symbol *symb)
138 /* Prefer a symbol with non zero length */
139 a = syma->end - syma->start;
140 b = symb->end - symb->start;
141 if ((b == 0) && (a > 0))
143 else if ((a == 0) && (b > 0))
146 /* Prefer a non weak symbol over a weak one */
147 a = syma->binding == STB_WEAK;
148 b = symb->binding == STB_WEAK;
154 /* Prefer a global symbol over a non global one */
155 a = syma->binding == STB_GLOBAL;
156 b = symb->binding == STB_GLOBAL;
162 /* Prefer a symbol with less underscores */
163 a = prefix_underscores_count(syma->name);
164 b = prefix_underscores_count(symb->name);
170 /* Choose the symbol with the longest name */
171 na = strlen(syma->name);
172 nb = strlen(symb->name);
178 return arch__choose_best_symbol(syma, symb);
181 void symbols__fixup_duplicate(struct rb_root_cached *symbols)
184 struct symbol *curr, *next;
186 if (symbol_conf.allow_aliases)
189 nd = rb_first_cached(symbols);
192 curr = rb_entry(nd, struct symbol, rb_node);
194 nd = rb_next(&curr->rb_node);
198 next = rb_entry(nd, struct symbol, rb_node);
199 if (curr->start != next->start)
202 if (choose_best_symbol(curr, next) == SYMBOL_A) {
203 if (next->type == STT_GNU_IFUNC)
204 curr->ifunc_alias = true;
205 rb_erase_cached(&next->rb_node, symbols);
206 symbol__delete(next);
209 if (curr->type == STT_GNU_IFUNC)
210 next->ifunc_alias = true;
211 nd = rb_next(&curr->rb_node);
212 rb_erase_cached(&curr->rb_node, symbols);
213 symbol__delete(curr);
218 /* Update zero-sized symbols using the address of the next symbol */
219 void symbols__fixup_end(struct rb_root_cached *symbols, bool is_kallsyms)
221 struct rb_node *nd, *prevnd = rb_first_cached(symbols);
222 struct symbol *curr, *prev;
227 curr = rb_entry(prevnd, struct symbol, rb_node);
229 for (nd = rb_next(prevnd); nd; nd = rb_next(nd)) {
231 curr = rb_entry(nd, struct symbol, rb_node);
234 * On some architecture kernel text segment start is located at
235 * some low memory address, while modules are located at high
236 * memory addresses (or vice versa). The gap between end of
237 * kernel text segment and beginning of first module's text
238 * segment is very big. Therefore do not fill this gap and do
239 * not assign it to the kernel dso map (kallsyms).
241 * In kallsyms, it determines module symbols using '[' character
243 * ffffffffc1937000 T hdmi_driver_init [snd_hda_codec_hdmi]
245 if (prev->end == prev->start) {
246 /* Last kernel/module symbol mapped to end of page */
247 if (is_kallsyms && (!strchr(prev->name, '[') !=
248 !strchr(curr->name, '[')))
249 prev->end = roundup(prev->end + 4096, 4096);
251 prev->end = curr->start;
253 pr_debug4("%s sym:%s end:%#" PRIx64 "\n",
254 __func__, prev->name, prev->end);
259 if (curr->end == curr->start)
260 curr->end = roundup(curr->start, 4096) + 4096;
263 struct symbol *symbol__new(u64 start, u64 len, u8 binding, u8 type, const char *name)
265 size_t namelen = strlen(name) + 1;
266 struct symbol *sym = calloc(1, (symbol_conf.priv_size +
267 sizeof(*sym) + namelen));
271 if (symbol_conf.priv_size) {
272 if (symbol_conf.init_annotation) {
273 struct annotation *notes = (void *)sym;
274 annotation__init(notes);
276 sym = ((void *)sym) + symbol_conf.priv_size;
280 sym->end = len ? start + len : start;
282 sym->binding = binding;
283 sym->namelen = namelen - 1;
285 pr_debug4("%s: %s %#" PRIx64 "-%#" PRIx64 "\n",
286 __func__, name, start, sym->end);
287 memcpy(sym->name, name, namelen);
292 void symbol__delete(struct symbol *sym)
294 if (symbol_conf.priv_size) {
295 if (symbol_conf.init_annotation) {
296 struct annotation *notes = symbol__annotation(sym);
298 annotation__exit(notes);
301 free(((void *)sym) - symbol_conf.priv_size);
304 void symbols__delete(struct rb_root_cached *symbols)
307 struct rb_node *next = rb_first_cached(symbols);
310 pos = rb_entry(next, struct symbol, rb_node);
311 next = rb_next(&pos->rb_node);
312 rb_erase_cached(&pos->rb_node, symbols);
317 void __symbols__insert(struct rb_root_cached *symbols,
318 struct symbol *sym, bool kernel)
320 struct rb_node **p = &symbols->rb_root.rb_node;
321 struct rb_node *parent = NULL;
322 const u64 ip = sym->start;
324 bool leftmost = true;
327 const char *name = sym->name;
329 * ppc64 uses function descriptors and appends a '.' to the
330 * start of every instruction address. Remove it.
334 sym->idle = symbol__is_idle(name);
339 s = rb_entry(parent, struct symbol, rb_node);
347 rb_link_node(&sym->rb_node, parent, p);
348 rb_insert_color_cached(&sym->rb_node, symbols, leftmost);
351 void symbols__insert(struct rb_root_cached *symbols, struct symbol *sym)
353 __symbols__insert(symbols, sym, false);
356 static struct symbol *symbols__find(struct rb_root_cached *symbols, u64 ip)
363 n = symbols->rb_root.rb_node;
366 struct symbol *s = rb_entry(n, struct symbol, rb_node);
370 else if (ip > s->end || (ip == s->end && ip != s->start))
379 static struct symbol *symbols__first(struct rb_root_cached *symbols)
381 struct rb_node *n = rb_first_cached(symbols);
384 return rb_entry(n, struct symbol, rb_node);
389 static struct symbol *symbols__last(struct rb_root_cached *symbols)
391 struct rb_node *n = rb_last(&symbols->rb_root);
394 return rb_entry(n, struct symbol, rb_node);
399 static struct symbol *symbols__next(struct symbol *sym)
401 struct rb_node *n = rb_next(&sym->rb_node);
404 return rb_entry(n, struct symbol, rb_node);
409 static int symbols__sort_name_cmp(const void *vlhs, const void *vrhs)
411 const struct symbol *lhs = *((const struct symbol **)vlhs);
412 const struct symbol *rhs = *((const struct symbol **)vrhs);
414 return strcmp(lhs->name, rhs->name);
417 static struct symbol **symbols__sort_by_name(struct rb_root_cached *source, size_t *len)
420 struct symbol **result;
421 size_t i = 0, size = 0;
423 for (nd = rb_first_cached(source); nd; nd = rb_next(nd))
426 result = malloc(sizeof(*result) * size);
430 for (nd = rb_first_cached(source); nd; nd = rb_next(nd)) {
431 struct symbol *pos = rb_entry(nd, struct symbol, rb_node);
435 qsort(result, size, sizeof(*result), symbols__sort_name_cmp);
440 int symbol__match_symbol_name(const char *name, const char *str,
441 enum symbol_tag_include includes)
443 const char *versioning;
445 if (includes == SYMBOL_TAG_INCLUDE__DEFAULT_ONLY &&
446 (versioning = strstr(name, "@@"))) {
447 int len = strlen(str);
449 if (len < versioning - name)
450 len = versioning - name;
452 return arch__compare_symbol_names_n(name, str, len);
454 return arch__compare_symbol_names(name, str);
457 static struct symbol *symbols__find_by_name(struct symbol *symbols[],
460 enum symbol_tag_include includes,
463 size_t i, lower = 0, upper = symbols_len;
464 struct symbol *s = NULL;
467 *found_idx = SIZE_MAX;
472 while (lower < upper) {
475 i = (lower + upper) / 2;
476 cmp = symbol__match_symbol_name(symbols[i]->name, name, includes);
489 if (s && includes != SYMBOL_TAG_INCLUDE__DEFAULT_ONLY) {
490 /* return first symbol that has same name (if any) */
492 struct symbol *tmp = symbols[i - 1];
494 if (!arch__compare_symbol_names(tmp->name, s->name)) {
502 assert(!found_idx || !s || s == symbols[*found_idx]);
506 void dso__reset_find_symbol_cache(struct dso *dso)
508 dso->last_find_result.addr = 0;
509 dso->last_find_result.symbol = NULL;
512 void dso__insert_symbol(struct dso *dso, struct symbol *sym)
514 __symbols__insert(&dso->symbols, sym, dso->kernel);
516 /* update the symbol cache if necessary */
517 if (dso->last_find_result.addr >= sym->start &&
518 (dso->last_find_result.addr < sym->end ||
519 sym->start == sym->end)) {
520 dso->last_find_result.symbol = sym;
524 void dso__delete_symbol(struct dso *dso, struct symbol *sym)
526 rb_erase_cached(&sym->rb_node, &dso->symbols);
528 dso__reset_find_symbol_cache(dso);
531 struct symbol *dso__find_symbol(struct dso *dso, u64 addr)
533 if (dso->last_find_result.addr != addr || dso->last_find_result.symbol == NULL) {
534 dso->last_find_result.addr = addr;
535 dso->last_find_result.symbol = symbols__find(&dso->symbols, addr);
538 return dso->last_find_result.symbol;
541 struct symbol *dso__find_symbol_nocache(struct dso *dso, u64 addr)
543 return symbols__find(&dso->symbols, addr);
546 struct symbol *dso__first_symbol(struct dso *dso)
548 return symbols__first(&dso->symbols);
551 struct symbol *dso__last_symbol(struct dso *dso)
553 return symbols__last(&dso->symbols);
556 struct symbol *dso__next_symbol(struct symbol *sym)
558 return symbols__next(sym);
561 struct symbol *dso__next_symbol_by_name(struct dso *dso, size_t *idx)
563 if (*idx + 1 >= dso->symbol_names_len)
567 return dso->symbol_names[*idx];
571 * Returns first symbol that matched with @name.
573 struct symbol *dso__find_symbol_by_name(struct dso *dso, const char *name, size_t *idx)
575 struct symbol *s = symbols__find_by_name(dso->symbol_names, dso->symbol_names_len,
576 name, SYMBOL_TAG_INCLUDE__NONE, idx);
578 s = symbols__find_by_name(dso->symbol_names, dso->symbol_names_len,
579 name, SYMBOL_TAG_INCLUDE__DEFAULT_ONLY, idx);
583 void dso__sort_by_name(struct dso *dso)
585 mutex_lock(&dso->lock);
586 if (!dso__sorted_by_name(dso)) {
589 dso->symbol_names = symbols__sort_by_name(&dso->symbols, &len);
590 if (dso->symbol_names) {
591 dso->symbol_names_len = len;
592 dso__set_sorted_by_name(dso);
595 mutex_unlock(&dso->lock);
599 * While we find nice hex chars, build a long_val.
600 * Return number of chars processed.
602 static int hex2u64(const char *ptr, u64 *long_val)
606 *long_val = strtoull(ptr, &p, 16);
612 int modules__parse(const char *filename, void *arg,
613 int (*process_module)(void *arg, const char *name,
614 u64 start, u64 size))
621 file = fopen(filename, "r");
631 line_len = getline(&line, &n, file);
644 line[--line_len] = '\0'; /* \n */
646 sep = strrchr(line, 'x');
650 hex2u64(sep + 1, &start);
652 sep = strchr(line, ' ');
658 scnprintf(name, sizeof(name), "[%s]", line);
660 size = strtoul(sep + 1, &endptr, 0);
661 if (*endptr != ' ' && *endptr != '\t')
664 err = process_module(arg, name, start, size);
675 * These are symbols in the kernel image, so make sure that
676 * sym is from a kernel DSO.
678 static bool symbol__is_idle(const char *name)
680 const char * const idle_symbols[] = {
681 "acpi_idle_do_entry",
682 "acpi_processor_ffh_cstate_enter",
694 "mwait_idle_with_hints",
695 "mwait_idle_with_hints.constprop.0",
697 "ppc64_runlatch_off",
698 "pseries_dedicated_idle_sleep",
704 static struct strlist *idle_symbols_list;
706 if (idle_symbols_list)
707 return strlist__has_entry(idle_symbols_list, name);
709 idle_symbols_list = strlist__new(NULL, NULL);
711 for (i = 0; idle_symbols[i]; i++)
712 strlist__add(idle_symbols_list, idle_symbols[i]);
714 return strlist__has_entry(idle_symbols_list, name);
717 static int map__process_kallsym_symbol(void *arg, const char *name,
718 char type, u64 start)
721 struct dso *dso = arg;
722 struct rb_root_cached *root = &dso->symbols;
724 if (!symbol_type__filter(type))
727 /* Ignore local symbols for ARM modules */
732 * module symbols are not sorted so we add all
733 * symbols, setting length to 0, and rely on
734 * symbols__fixup_end() to fix it up.
736 sym = symbol__new(start, 0, kallsyms2elf_binding(type), kallsyms2elf_type(type), name);
740 * We will pass the symbols to the filter later, in
741 * map__split_kallsyms, when we have split the maps per module
743 __symbols__insert(root, sym, !strchr(name, '['));
749 * Loads the function entries in /proc/kallsyms into kernel_map->dso,
750 * so that we can in the next step set the symbol ->end address and then
751 * call kernel_maps__split_kallsyms.
753 static int dso__load_all_kallsyms(struct dso *dso, const char *filename)
755 return kallsyms__parse(filename, dso, map__process_kallsym_symbol);
758 static int maps__split_kallsyms_for_kcore(struct maps *kmaps, struct dso *dso)
760 struct map *curr_map;
763 struct rb_root_cached old_root = dso->symbols;
764 struct rb_root_cached *root = &dso->symbols;
765 struct rb_node *next = rb_first_cached(root);
770 *root = RB_ROOT_CACHED;
773 struct dso *curr_map_dso;
776 pos = rb_entry(next, struct symbol, rb_node);
777 next = rb_next(&pos->rb_node);
779 rb_erase_cached(&pos->rb_node, &old_root);
780 RB_CLEAR_NODE(&pos->rb_node);
781 module = strchr(pos->name, '\t');
785 curr_map = maps__find(kmaps, pos->start);
791 curr_map_dso = map__dso(curr_map);
792 pos->start -= map__start(curr_map) - map__pgoff(curr_map);
793 if (pos->end > map__end(curr_map))
794 pos->end = map__end(curr_map);
796 pos->end -= map__start(curr_map) - map__pgoff(curr_map);
797 symbols__insert(&curr_map_dso->symbols, pos);
801 /* Symbols have been adjusted */
802 dso->adjust_symbols = 1;
808 * Split the symbols into maps, making sure there are no overlaps, i.e. the
809 * kernel range is broken in several maps, named [kernel].N, as we don't have
810 * the original ELF section names vmlinux have.
812 static int maps__split_kallsyms(struct maps *kmaps, struct dso *dso, u64 delta,
813 struct map *initial_map)
815 struct machine *machine;
816 struct map *curr_map = initial_map;
818 int count = 0, moved = 0;
819 struct rb_root_cached *root = &dso->symbols;
820 struct rb_node *next = rb_first_cached(root);
821 int kernel_range = 0;
827 machine = maps__machine(kmaps);
829 x86_64 = machine__is(machine, "x86_64");
834 pos = rb_entry(next, struct symbol, rb_node);
835 next = rb_next(&pos->rb_node);
837 module = strchr(pos->name, '\t');
839 struct dso *curr_map_dso;
841 if (!symbol_conf.use_modules)
845 curr_map_dso = map__dso(curr_map);
846 if (strcmp(curr_map_dso->short_name, module)) {
847 if (!RC_CHK_EQUAL(curr_map, initial_map) &&
848 dso->kernel == DSO_SPACE__KERNEL_GUEST &&
849 machine__is_default_guest(machine)) {
851 * We assume all symbols of a module are
852 * continuous in * kallsyms, so curr_map
853 * points to a module and all its
854 * symbols are in its kmap. Mark it as
857 dso__set_loaded(curr_map_dso);
860 curr_map = maps__find_by_name(kmaps, module);
861 if (curr_map == NULL) {
862 pr_debug("%s/proc/{kallsyms,modules} "
863 "inconsistency while looking "
864 "for \"%s\" module!\n",
865 machine->root_dir, module);
866 curr_map = initial_map;
869 curr_map_dso = map__dso(curr_map);
870 if (curr_map_dso->loaded &&
871 !machine__is_default_guest(machine))
875 * So that we look just like we get from .ko files,
876 * i.e. not prelinked, relative to initial_map->start.
878 pos->start = map__map_ip(curr_map, pos->start);
879 pos->end = map__map_ip(curr_map, pos->end);
880 } else if (x86_64 && is_entry_trampoline(pos->name)) {
882 * These symbols are not needed anymore since the
883 * trampoline maps refer to the text section and it's
884 * symbols instead. Avoid having to deal with
885 * relocations, and the assumption that the first symbol
886 * is the start of kernel text, by simply removing the
887 * symbols at this point.
890 } else if (curr_map != initial_map) {
891 char dso_name[PATH_MAX];
895 /* Kernel was relocated at boot time */
901 curr_map = initial_map;
905 if (dso->kernel == DSO_SPACE__KERNEL_GUEST)
906 snprintf(dso_name, sizeof(dso_name),
910 snprintf(dso_name, sizeof(dso_name),
914 ndso = dso__new(dso_name);
918 ndso->kernel = dso->kernel;
920 curr_map = map__new2(pos->start, ndso);
921 if (curr_map == NULL) {
926 map__set_mapping_type(curr_map, MAPPING_TYPE__IDENTITY);
927 if (maps__insert(kmaps, curr_map)) {
933 /* Kernel was relocated at boot time */
938 if (curr_map != initial_map) {
939 struct dso *curr_map_dso = map__dso(curr_map);
941 rb_erase_cached(&pos->rb_node, root);
942 symbols__insert(&curr_map_dso->symbols, pos);
949 rb_erase_cached(&pos->rb_node, root);
953 if (curr_map != initial_map &&
954 dso->kernel == DSO_SPACE__KERNEL_GUEST &&
955 machine__is_default_guest(maps__machine(kmaps))) {
956 dso__set_loaded(map__dso(curr_map));
959 return count + moved;
962 bool symbol__restricted_filename(const char *filename,
963 const char *restricted_filename)
965 bool restricted = false;
967 if (symbol_conf.kptr_restrict) {
968 char *r = realpath(filename, NULL);
971 restricted = strcmp(r, restricted_filename) == 0;
981 struct rb_node rb_node;
986 static void add_module(struct module_info *mi, struct rb_root *modules)
988 struct rb_node **p = &modules->rb_node;
989 struct rb_node *parent = NULL;
990 struct module_info *m;
994 m = rb_entry(parent, struct module_info, rb_node);
995 if (strcmp(mi->name, m->name) < 0)
1000 rb_link_node(&mi->rb_node, parent, p);
1001 rb_insert_color(&mi->rb_node, modules);
1004 static void delete_modules(struct rb_root *modules)
1006 struct module_info *mi;
1007 struct rb_node *next = rb_first(modules);
1010 mi = rb_entry(next, struct module_info, rb_node);
1011 next = rb_next(&mi->rb_node);
1012 rb_erase(&mi->rb_node, modules);
1018 static struct module_info *find_module(const char *name,
1019 struct rb_root *modules)
1021 struct rb_node *n = modules->rb_node;
1024 struct module_info *m;
1027 m = rb_entry(n, struct module_info, rb_node);
1028 cmp = strcmp(name, m->name);
1040 static int __read_proc_modules(void *arg, const char *name, u64 start,
1041 u64 size __maybe_unused)
1043 struct rb_root *modules = arg;
1044 struct module_info *mi;
1046 mi = zalloc(sizeof(struct module_info));
1050 mi->name = strdup(name);
1058 add_module(mi, modules);
1063 static int read_proc_modules(const char *filename, struct rb_root *modules)
1065 if (symbol__restricted_filename(filename, "/proc/modules"))
1068 if (modules__parse(filename, modules, __read_proc_modules)) {
1069 delete_modules(modules);
1076 int compare_proc_modules(const char *from, const char *to)
1078 struct rb_root from_modules = RB_ROOT;
1079 struct rb_root to_modules = RB_ROOT;
1080 struct rb_node *from_node, *to_node;
1081 struct module_info *from_m, *to_m;
1084 if (read_proc_modules(from, &from_modules))
1087 if (read_proc_modules(to, &to_modules))
1088 goto out_delete_from;
1090 from_node = rb_first(&from_modules);
1091 to_node = rb_first(&to_modules);
1096 from_m = rb_entry(from_node, struct module_info, rb_node);
1097 to_m = rb_entry(to_node, struct module_info, rb_node);
1099 if (from_m->start != to_m->start ||
1100 strcmp(from_m->name, to_m->name))
1103 from_node = rb_next(from_node);
1104 to_node = rb_next(to_node);
1107 if (!from_node && !to_node)
1110 delete_modules(&to_modules);
1112 delete_modules(&from_modules);
1117 static int do_validate_kcore_modules_cb(struct map *old_map, void *data)
1119 struct rb_root *modules = data;
1120 struct module_info *mi;
1123 if (!__map__is_kmodule(old_map))
1126 dso = map__dso(old_map);
1127 /* Module must be in memory at the same address */
1128 mi = find_module(dso->short_name, modules);
1129 if (!mi || mi->start != map__start(old_map))
1135 static int do_validate_kcore_modules(const char *filename, struct maps *kmaps)
1137 struct rb_root modules = RB_ROOT;
1140 err = read_proc_modules(filename, &modules);
1144 err = maps__for_each_map(kmaps, do_validate_kcore_modules_cb, &modules);
1146 delete_modules(&modules);
1151 * If kallsyms is referenced by name then we look for filename in the same
1154 static bool filename_from_kallsyms_filename(char *filename,
1155 const char *base_name,
1156 const char *kallsyms_filename)
1160 strcpy(filename, kallsyms_filename);
1161 name = strrchr(filename, '/');
1167 if (!strcmp(name, "kallsyms")) {
1168 strcpy(name, base_name);
1175 static int validate_kcore_modules(const char *kallsyms_filename,
1178 struct maps *kmaps = map__kmaps(map);
1179 char modules_filename[PATH_MAX];
1184 if (!filename_from_kallsyms_filename(modules_filename, "modules",
1188 if (do_validate_kcore_modules(modules_filename, kmaps))
1194 static int validate_kcore_addresses(const char *kallsyms_filename,
1197 struct kmap *kmap = map__kmap(map);
1202 if (kmap->ref_reloc_sym && kmap->ref_reloc_sym->name) {
1205 if (kallsyms__get_function_start(kallsyms_filename,
1206 kmap->ref_reloc_sym->name, &start))
1208 if (start != kmap->ref_reloc_sym->addr)
1212 return validate_kcore_modules(kallsyms_filename, map);
1215 struct kcore_mapfn_data {
1217 struct list_head maps;
1220 static int kcore_mapfn(u64 start, u64 len, u64 pgoff, void *data)
1222 struct kcore_mapfn_data *md = data;
1223 struct map_list_node *list_node = map_list_node__new();
1228 list_node->map = map__new2(start, md->dso);
1229 if (!list_node->map) {
1234 map__set_end(list_node->map, map__start(list_node->map) + len);
1235 map__set_pgoff(list_node->map, pgoff);
1237 list_add(&list_node->node, &md->maps);
1242 static bool remove_old_maps(struct map *map, void *data)
1244 const struct map *map_to_save = data;
1247 * We need to preserve eBPF maps even if they are covered by kcore,
1248 * because we need to access eBPF dso for source data.
1250 return !RC_CHK_EQUAL(map, map_to_save) && !__map__is_bpf_prog(map);
1253 static int dso__load_kcore(struct dso *dso, struct map *map,
1254 const char *kallsyms_filename)
1256 struct maps *kmaps = map__kmaps(map);
1257 struct kcore_mapfn_data md;
1258 struct map *replacement_map = NULL;
1259 struct machine *machine;
1262 char kcore_filename[PATH_MAX];
1268 machine = maps__machine(kmaps);
1270 /* This function requires that the map is the kernel map */
1271 if (!__map__is_kernel(map))
1274 if (!filename_from_kallsyms_filename(kcore_filename, "kcore",
1278 /* Modules and kernel must be present at their original addresses */
1279 if (validate_kcore_addresses(kallsyms_filename, map))
1283 INIT_LIST_HEAD(&md.maps);
1285 fd = open(kcore_filename, O_RDONLY);
1287 pr_debug("Failed to open %s. Note /proc/kcore requires CAP_SYS_RAWIO capability to access.\n",
1292 /* Read new maps into temporary lists */
1293 err = file__read_maps(fd, map__prot(map) & PROT_EXEC, kcore_mapfn, &md,
1297 dso->is_64_bit = is_64_bit;
1299 if (list_empty(&md.maps)) {
1304 /* Remove old maps */
1305 maps__remove_maps(kmaps, remove_old_maps, map);
1306 machine->trampolines_mapped = false;
1308 /* Find the kernel map using the '_stext' symbol */
1309 if (!kallsyms__get_function_start(kallsyms_filename, "_stext", &stext)) {
1310 u64 replacement_size = 0;
1311 struct map_list_node *new_node;
1313 list_for_each_entry(new_node, &md.maps, node) {
1314 struct map *new_map = new_node->map;
1315 u64 new_size = map__size(new_map);
1317 if (!(stext >= map__start(new_map) && stext < map__end(new_map)))
1321 * On some architectures, ARM64 for example, the kernel
1322 * text can get allocated inside of the vmalloc segment.
1323 * Select the smallest matching segment, in case stext
1324 * falls within more than one in the list.
1326 if (!replacement_map || new_size < replacement_size) {
1327 replacement_map = new_map;
1328 replacement_size = new_size;
1333 if (!replacement_map)
1334 replacement_map = list_entry(md.maps.next, struct map_list_node, node)->map;
1337 while (!list_empty(&md.maps)) {
1338 struct map_list_node *new_node = list_entry(md.maps.next, struct map_list_node, node);
1339 struct map *new_map = new_node->map;
1341 list_del_init(&new_node->node);
1343 if (RC_CHK_EQUAL(new_map, replacement_map)) {
1344 struct map *map_ref;
1346 map__set_start(map, map__start(new_map));
1347 map__set_end(map, map__end(new_map));
1348 map__set_pgoff(map, map__pgoff(new_map));
1349 map__set_mapping_type(map, map__mapping_type(new_map));
1350 /* Ensure maps are correctly ordered */
1351 map_ref = map__get(map);
1352 maps__remove(kmaps, map_ref);
1353 err = maps__insert(kmaps, map_ref);
1360 * Merge kcore map into existing maps,
1361 * and ensure that current maps (eBPF)
1364 if (maps__merge_in(kmaps, new_map)) {
1372 if (machine__is(machine, "x86_64")) {
1376 * If one of the corresponding symbols is there, assume the
1377 * entry trampoline maps are too.
1379 if (!kallsyms__get_function_start(kallsyms_filename,
1380 ENTRY_TRAMPOLINE_NAME,
1382 machine->trampolines_mapped = true;
1386 * Set the data type and long name so that kcore can be read via
1387 * dso__data_read_addr().
1389 if (dso->kernel == DSO_SPACE__KERNEL_GUEST)
1390 dso->binary_type = DSO_BINARY_TYPE__GUEST_KCORE;
1392 dso->binary_type = DSO_BINARY_TYPE__KCORE;
1393 dso__set_long_name(dso, strdup(kcore_filename), true);
1397 if (map__prot(map) & PROT_EXEC)
1398 pr_debug("Using %s for kernel object code\n", kcore_filename);
1400 pr_debug("Using %s for kernel data\n", kcore_filename);
1405 while (!list_empty(&md.maps)) {
1406 struct map_list_node *list_node;
1408 list_node = list_entry(md.maps.next, struct map_list_node, node);
1409 list_del_init(&list_node->node);
1410 map__zput(list_node->map);
1418 * If the kernel is relocated at boot time, kallsyms won't match. Compute the
1419 * delta based on the relocation reference symbol.
1421 static int kallsyms__delta(struct kmap *kmap, const char *filename, u64 *delta)
1425 if (!kmap->ref_reloc_sym || !kmap->ref_reloc_sym->name)
1428 if (kallsyms__get_function_start(filename, kmap->ref_reloc_sym->name, &addr))
1431 *delta = addr - kmap->ref_reloc_sym->addr;
1435 int __dso__load_kallsyms(struct dso *dso, const char *filename,
1436 struct map *map, bool no_kcore)
1438 struct kmap *kmap = map__kmap(map);
1441 if (symbol__restricted_filename(filename, "/proc/kallsyms"))
1444 if (!kmap || !kmap->kmaps)
1447 if (dso__load_all_kallsyms(dso, filename) < 0)
1450 if (kallsyms__delta(kmap, filename, &delta))
1453 symbols__fixup_end(&dso->symbols, true);
1454 symbols__fixup_duplicate(&dso->symbols);
1456 if (dso->kernel == DSO_SPACE__KERNEL_GUEST)
1457 dso->symtab_type = DSO_BINARY_TYPE__GUEST_KALLSYMS;
1459 dso->symtab_type = DSO_BINARY_TYPE__KALLSYMS;
1461 if (!no_kcore && !dso__load_kcore(dso, map, filename))
1462 return maps__split_kallsyms_for_kcore(kmap->kmaps, dso);
1464 return maps__split_kallsyms(kmap->kmaps, dso, delta, map);
1467 int dso__load_kallsyms(struct dso *dso, const char *filename,
1470 return __dso__load_kallsyms(dso, filename, map, false);
1473 static int dso__load_perf_map(const char *map_path, struct dso *dso)
1480 file = fopen(map_path, "r");
1484 while (!feof(file)) {
1489 line_len = getline(&line, &n, file);
1496 line[--line_len] = '\0'; /* \n */
1498 len = hex2u64(line, &start);
1501 if (len + 2 >= line_len)
1504 len += hex2u64(line + len, &size);
1507 if (len + 2 >= line_len)
1510 sym = symbol__new(start, size, STB_GLOBAL, STT_FUNC, line + len);
1513 goto out_delete_line;
1515 symbols__insert(&dso->symbols, sym);
1530 #ifdef HAVE_LIBBFD_SUPPORT
1531 #define PACKAGE 'perf'
1534 static int bfd_symbols__cmpvalue(const void *a, const void *b)
1536 const asymbol *as = *(const asymbol **)a, *bs = *(const asymbol **)b;
1538 if (bfd_asymbol_value(as) != bfd_asymbol_value(bs))
1539 return bfd_asymbol_value(as) - bfd_asymbol_value(bs);
1541 return bfd_asymbol_name(as)[0] - bfd_asymbol_name(bs)[0];
1544 static int bfd2elf_binding(asymbol *symbol)
1546 if (symbol->flags & BSF_WEAK)
1548 if (symbol->flags & BSF_GLOBAL)
1550 if (symbol->flags & BSF_LOCAL)
1555 int dso__load_bfd_symbols(struct dso *dso, const char *debugfile)
1558 long symbols_size, symbols_count, i;
1560 asymbol **symbols, *sym;
1561 struct symbol *symbol;
1565 abfd = bfd_openr(debugfile, NULL);
1569 if (!bfd_check_format(abfd, bfd_object)) {
1570 pr_debug2("%s: cannot read %s bfd file.\n", __func__,
1575 if (bfd_get_flavour(abfd) == bfd_target_elf_flavour)
1578 symbols_size = bfd_get_symtab_upper_bound(abfd);
1579 if (symbols_size == 0) {
1584 if (symbols_size < 0)
1587 symbols = malloc(symbols_size);
1591 symbols_count = bfd_canonicalize_symtab(abfd, symbols);
1592 if (symbols_count < 0)
1595 section = bfd_get_section_by_name(abfd, ".text");
1597 for (i = 0; i < symbols_count; ++i) {
1598 if (!strcmp(bfd_asymbol_name(symbols[i]), "__ImageBase") ||
1599 !strcmp(bfd_asymbol_name(symbols[i]), "__image_base__"))
1602 if (i < symbols_count) {
1603 /* PE symbols can only have 4 bytes, so use .text high bits */
1604 dso->text_offset = section->vma - (u32)section->vma;
1605 dso->text_offset += (u32)bfd_asymbol_value(symbols[i]);
1606 dso->text_end = (section->vma - dso->text_offset) + section->size;
1608 dso->text_offset = section->vma - section->filepos;
1609 dso->text_end = section->filepos + section->size;
1613 qsort(symbols, symbols_count, sizeof(asymbol *), bfd_symbols__cmpvalue);
1615 #ifdef bfd_get_section
1616 #define bfd_asymbol_section bfd_get_section
1618 for (i = 0; i < symbols_count; ++i) {
1620 section = bfd_asymbol_section(sym);
1621 if (bfd2elf_binding(sym) < 0)
1624 while (i + 1 < symbols_count &&
1625 bfd_asymbol_section(symbols[i + 1]) == section &&
1626 bfd2elf_binding(symbols[i + 1]) < 0)
1629 if (i + 1 < symbols_count &&
1630 bfd_asymbol_section(symbols[i + 1]) == section)
1631 len = symbols[i + 1]->value - sym->value;
1633 len = section->size - sym->value;
1635 start = bfd_asymbol_value(sym) - dso->text_offset;
1636 symbol = symbol__new(start, len, bfd2elf_binding(sym), STT_FUNC,
1637 bfd_asymbol_name(sym));
1641 symbols__insert(&dso->symbols, symbol);
1643 #ifdef bfd_get_section
1644 #undef bfd_asymbol_section
1647 symbols__fixup_end(&dso->symbols, false);
1648 symbols__fixup_duplicate(&dso->symbols);
1649 dso->adjust_symbols = 1;
1660 static bool dso__is_compatible_symtab_type(struct dso *dso, bool kmod,
1661 enum dso_binary_type type)
1664 case DSO_BINARY_TYPE__JAVA_JIT:
1665 case DSO_BINARY_TYPE__DEBUGLINK:
1666 case DSO_BINARY_TYPE__SYSTEM_PATH_DSO:
1667 case DSO_BINARY_TYPE__FEDORA_DEBUGINFO:
1668 case DSO_BINARY_TYPE__UBUNTU_DEBUGINFO:
1669 case DSO_BINARY_TYPE__MIXEDUP_UBUNTU_DEBUGINFO:
1670 case DSO_BINARY_TYPE__BUILDID_DEBUGINFO:
1671 case DSO_BINARY_TYPE__OPENEMBEDDED_DEBUGINFO:
1672 return !kmod && dso->kernel == DSO_SPACE__USER;
1674 case DSO_BINARY_TYPE__KALLSYMS:
1675 case DSO_BINARY_TYPE__VMLINUX:
1676 case DSO_BINARY_TYPE__KCORE:
1677 return dso->kernel == DSO_SPACE__KERNEL;
1679 case DSO_BINARY_TYPE__GUEST_KALLSYMS:
1680 case DSO_BINARY_TYPE__GUEST_VMLINUX:
1681 case DSO_BINARY_TYPE__GUEST_KCORE:
1682 return dso->kernel == DSO_SPACE__KERNEL_GUEST;
1684 case DSO_BINARY_TYPE__GUEST_KMODULE:
1685 case DSO_BINARY_TYPE__GUEST_KMODULE_COMP:
1686 case DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE:
1687 case DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP:
1689 * kernel modules know their symtab type - it's set when
1690 * creating a module dso in machine__addnew_module_map().
1692 return kmod && dso->symtab_type == type;
1694 case DSO_BINARY_TYPE__BUILD_ID_CACHE:
1695 case DSO_BINARY_TYPE__BUILD_ID_CACHE_DEBUGINFO:
1698 case DSO_BINARY_TYPE__BPF_PROG_INFO:
1699 case DSO_BINARY_TYPE__BPF_IMAGE:
1700 case DSO_BINARY_TYPE__OOL:
1701 case DSO_BINARY_TYPE__NOT_FOUND:
1707 /* Checks for the existence of the perf-<pid>.map file in two different
1708 * locations. First, if the process is a separate mount namespace, check in
1709 * that namespace using the pid of the innermost pid namespace. If's not in a
1710 * namespace, or the file can't be found there, try in the mount namespace of
1711 * the tracing process using our view of its pid.
1713 static int dso__find_perf_map(char *filebuf, size_t bufsz,
1714 struct nsinfo **nsip)
1716 struct nscookie nsc;
1718 struct nsinfo *nnsi;
1723 if (nsinfo__need_setns(nsi)) {
1724 snprintf(filebuf, bufsz, "/tmp/perf-%d.map", nsinfo__nstgid(nsi));
1725 nsinfo__mountns_enter(nsi, &nsc);
1726 rc = access(filebuf, R_OK);
1727 nsinfo__mountns_exit(&nsc);
1732 nnsi = nsinfo__copy(nsi);
1736 nsinfo__clear_need_setns(nnsi);
1737 snprintf(filebuf, bufsz, "/tmp/perf-%d.map", nsinfo__tgid(nnsi));
1745 int dso__load(struct dso *dso, struct map *map)
1750 struct machine *machine = NULL;
1751 char *root_dir = (char *) "";
1753 struct symsrc ss_[2];
1754 struct symsrc *syms_ss = NULL, *runtime_ss = NULL;
1757 struct build_id bid;
1758 struct nscookie nsc;
1759 char newmapname[PATH_MAX];
1760 const char *map_path = dso->long_name;
1762 mutex_lock(&dso->lock);
1763 perfmap = strncmp(dso->name, "/tmp/perf-", 10) == 0;
1765 if (dso->nsinfo && (dso__find_perf_map(newmapname,
1766 sizeof(newmapname), &dso->nsinfo) == 0)) {
1767 map_path = newmapname;
1771 nsinfo__mountns_enter(dso->nsinfo, &nsc);
1773 /* check again under the dso->lock */
1774 if (dso__loaded(dso)) {
1779 kmod = dso->symtab_type == DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE ||
1780 dso->symtab_type == DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP ||
1781 dso->symtab_type == DSO_BINARY_TYPE__GUEST_KMODULE ||
1782 dso->symtab_type == DSO_BINARY_TYPE__GUEST_KMODULE_COMP;
1784 if (dso->kernel && !kmod) {
1785 if (dso->kernel == DSO_SPACE__KERNEL)
1786 ret = dso__load_kernel_sym(dso, map);
1787 else if (dso->kernel == DSO_SPACE__KERNEL_GUEST)
1788 ret = dso__load_guest_kernel_sym(dso, map);
1790 machine = maps__machine(map__kmaps(map));
1791 if (machine__is(machine, "x86_64"))
1792 machine__map_x86_64_entry_trampolines(machine, dso);
1796 dso->adjust_symbols = 0;
1799 ret = dso__load_perf_map(map_path, dso);
1800 dso->symtab_type = ret > 0 ? DSO_BINARY_TYPE__JAVA_JIT :
1801 DSO_BINARY_TYPE__NOT_FOUND;
1806 root_dir = machine->root_dir;
1808 name = malloc(PATH_MAX);
1813 * Read the build id if possible. This is required for
1814 * DSO_BINARY_TYPE__BUILDID_DEBUGINFO to work
1816 if (!dso->has_build_id &&
1817 is_regular_file(dso->long_name)) {
1818 __symbol__join_symfs(name, PATH_MAX, dso->long_name);
1819 if (filename__read_build_id(name, &bid) > 0)
1820 dso__set_build_id(dso, &bid);
1824 * Iterate over candidate debug images.
1825 * Keep track of "interesting" ones (those which have a symtab, dynsym,
1826 * and/or opd section) for processing.
1828 for (i = 0; i < DSO_BINARY_TYPE__SYMTAB_CNT; i++) {
1829 struct symsrc *ss = &ss_[ss_pos];
1830 bool next_slot = false;
1836 enum dso_binary_type symtab_type = binary_type_symtab[i];
1838 nsexit = (symtab_type == DSO_BINARY_TYPE__BUILD_ID_CACHE ||
1839 symtab_type == DSO_BINARY_TYPE__BUILD_ID_CACHE_DEBUGINFO);
1841 if (!dso__is_compatible_symtab_type(dso, kmod, symtab_type))
1844 if (dso__read_binary_type_filename(dso, symtab_type,
1845 root_dir, name, PATH_MAX))
1849 nsinfo__mountns_exit(&nsc);
1851 is_reg = is_regular_file(name);
1852 if (!is_reg && errno == ENOENT && dso->nsinfo) {
1853 char *new_name = dso__filename_with_chroot(dso, name);
1855 is_reg = is_regular_file(new_name);
1856 strlcpy(name, new_name, PATH_MAX);
1861 #ifdef HAVE_LIBBFD_SUPPORT
1863 bfdrc = dso__load_bfd_symbols(dso, name);
1865 if (is_reg && bfdrc < 0)
1866 sirc = symsrc__init(ss, dso, name, symtab_type);
1869 nsinfo__mountns_enter(dso->nsinfo, &nsc);
1876 if (!is_reg || sirc < 0)
1879 if (!syms_ss && symsrc__has_symtab(ss)) {
1882 if (!dso->symsrc_filename)
1883 dso->symsrc_filename = strdup(name);
1886 if (!runtime_ss && symsrc__possibly_runtime(ss)) {
1894 if (syms_ss && runtime_ss)
1897 symsrc__destroy(ss);
1902 if (!runtime_ss && !syms_ss)
1905 if (runtime_ss && !syms_ss) {
1906 syms_ss = runtime_ss;
1909 /* We'll have to hope for the best */
1910 if (!runtime_ss && syms_ss)
1911 runtime_ss = syms_ss;
1914 ret = dso__load_sym(dso, map, syms_ss, runtime_ss, kmod);
1921 nr_plt = dso__synthesize_plt_symbols(dso, runtime_ss);
1926 for (; ss_pos > 0; ss_pos--)
1927 symsrc__destroy(&ss_[ss_pos - 1]);
1930 if (ret < 0 && strstr(dso->name, " (deleted)") != NULL)
1933 dso__set_loaded(dso);
1934 mutex_unlock(&dso->lock);
1935 nsinfo__mountns_exit(&nsc);
1940 int dso__load_vmlinux(struct dso *dso, struct map *map,
1941 const char *vmlinux, bool vmlinux_allocated)
1945 char symfs_vmlinux[PATH_MAX];
1946 enum dso_binary_type symtab_type;
1948 if (vmlinux[0] == '/')
1949 snprintf(symfs_vmlinux, sizeof(symfs_vmlinux), "%s", vmlinux);
1951 symbol__join_symfs(symfs_vmlinux, vmlinux);
1953 if (dso->kernel == DSO_SPACE__KERNEL_GUEST)
1954 symtab_type = DSO_BINARY_TYPE__GUEST_VMLINUX;
1956 symtab_type = DSO_BINARY_TYPE__VMLINUX;
1958 if (symsrc__init(&ss, dso, symfs_vmlinux, symtab_type))
1962 * dso__load_sym() may copy 'dso' which will result in the copies having
1963 * an incorrect long name unless we set it here first.
1965 dso__set_long_name(dso, vmlinux, vmlinux_allocated);
1966 if (dso->kernel == DSO_SPACE__KERNEL_GUEST)
1967 dso->binary_type = DSO_BINARY_TYPE__GUEST_VMLINUX;
1969 dso->binary_type = DSO_BINARY_TYPE__VMLINUX;
1971 err = dso__load_sym(dso, map, &ss, &ss, 0);
1972 symsrc__destroy(&ss);
1975 dso__set_loaded(dso);
1976 pr_debug("Using %s for symbols\n", symfs_vmlinux);
1982 int dso__load_vmlinux_path(struct dso *dso, struct map *map)
1985 char *filename = NULL;
1987 pr_debug("Looking at the vmlinux_path (%d entries long)\n",
1988 vmlinux_path__nr_entries + 1);
1990 for (i = 0; i < vmlinux_path__nr_entries; ++i) {
1991 err = dso__load_vmlinux(dso, map, vmlinux_path[i], false);
1996 if (!symbol_conf.ignore_vmlinux_buildid)
1997 filename = dso__build_id_filename(dso, NULL, 0, false);
1998 if (filename != NULL) {
1999 err = dso__load_vmlinux(dso, map, filename, true);
2008 static bool visible_dir_filter(const char *name, struct dirent *d)
2010 if (d->d_type != DT_DIR)
2012 return lsdir_no_dot_filter(name, d);
2015 static int find_matching_kcore(struct map *map, char *dir, size_t dir_sz)
2017 char kallsyms_filename[PATH_MAX];
2019 struct strlist *dirs;
2020 struct str_node *nd;
2022 dirs = lsdir(dir, visible_dir_filter);
2026 strlist__for_each_entry(nd, dirs) {
2027 scnprintf(kallsyms_filename, sizeof(kallsyms_filename),
2028 "%s/%s/kallsyms", dir, nd->s);
2029 if (!validate_kcore_addresses(kallsyms_filename, map)) {
2030 strlcpy(dir, kallsyms_filename, dir_sz);
2036 strlist__delete(dirs);
2042 * Use open(O_RDONLY) to check readability directly instead of access(R_OK)
2043 * since access(R_OK) only checks with real UID/GID but open() use effective
2044 * UID/GID and actual capabilities (e.g. /proc/kcore requires CAP_SYS_RAWIO).
2046 static bool filename__readable(const char *file)
2048 int fd = open(file, O_RDONLY);
2055 static char *dso__find_kallsyms(struct dso *dso, struct map *map)
2057 struct build_id bid;
2058 char sbuild_id[SBUILD_ID_SIZE];
2059 bool is_host = false;
2060 char path[PATH_MAX];
2062 if (!dso->has_build_id) {
2064 * Last resort, if we don't have a build-id and couldn't find
2065 * any vmlinux file, try the running kernel kallsyms table.
2070 if (sysfs__read_build_id("/sys/kernel/notes", &bid) == 0)
2071 is_host = dso__build_id_equal(dso, &bid);
2073 /* Try a fast path for /proc/kallsyms if possible */
2076 * Do not check the build-id cache, unless we know we cannot use
2077 * /proc/kcore or module maps don't match to /proc/kallsyms.
2078 * To check readability of /proc/kcore, do not use access(R_OK)
2079 * since /proc/kcore requires CAP_SYS_RAWIO to read and access
2082 if (filename__readable("/proc/kcore") &&
2083 !validate_kcore_addresses("/proc/kallsyms", map))
2087 build_id__sprintf(&dso->bid, sbuild_id);
2089 /* Find kallsyms in build-id cache with kcore */
2090 scnprintf(path, sizeof(path), "%s/%s/%s",
2091 buildid_dir, DSO__NAME_KCORE, sbuild_id);
2093 if (!find_matching_kcore(map, path, sizeof(path)))
2094 return strdup(path);
2096 /* Use current /proc/kallsyms if possible */
2099 return strdup("/proc/kallsyms");
2102 /* Finally, find a cache of kallsyms */
2103 if (!build_id_cache__kallsyms_path(sbuild_id, path, sizeof(path))) {
2104 pr_err("No kallsyms or vmlinux with build-id %s was found\n",
2109 return strdup(path);
2112 static int dso__load_kernel_sym(struct dso *dso, struct map *map)
2115 const char *kallsyms_filename = NULL;
2116 char *kallsyms_allocated_filename = NULL;
2117 char *filename = NULL;
2120 * Step 1: if the user specified a kallsyms or vmlinux filename, use
2121 * it and only it, reporting errors to the user if it cannot be used.
2123 * For instance, try to analyse an ARM perf.data file _without_ a
2124 * build-id, or if the user specifies the wrong path to the right
2125 * vmlinux file, obviously we can't fallback to another vmlinux (a
2126 * x86_86 one, on the machine where analysis is being performed, say),
2127 * or worse, /proc/kallsyms.
2129 * If the specified file _has_ a build-id and there is a build-id
2130 * section in the perf.data file, we will still do the expected
2131 * validation in dso__load_vmlinux and will bail out if they don't
2134 if (symbol_conf.kallsyms_name != NULL) {
2135 kallsyms_filename = symbol_conf.kallsyms_name;
2139 if (!symbol_conf.ignore_vmlinux && symbol_conf.vmlinux_name != NULL) {
2140 return dso__load_vmlinux(dso, map, symbol_conf.vmlinux_name, false);
2144 * Before checking on common vmlinux locations, check if it's
2145 * stored as standard build id binary (not kallsyms) under
2148 if (!symbol_conf.ignore_vmlinux_buildid)
2149 filename = __dso__build_id_filename(dso, NULL, 0, false, false);
2150 if (filename != NULL) {
2151 err = dso__load_vmlinux(dso, map, filename, true);
2157 if (!symbol_conf.ignore_vmlinux && vmlinux_path != NULL) {
2158 err = dso__load_vmlinux_path(dso, map);
2163 /* do not try local files if a symfs was given */
2164 if (symbol_conf.symfs[0] != 0)
2167 kallsyms_allocated_filename = dso__find_kallsyms(dso, map);
2168 if (!kallsyms_allocated_filename)
2171 kallsyms_filename = kallsyms_allocated_filename;
2174 err = dso__load_kallsyms(dso, kallsyms_filename, map);
2176 pr_debug("Using %s for symbols\n", kallsyms_filename);
2177 free(kallsyms_allocated_filename);
2179 if (err > 0 && !dso__is_kcore(dso)) {
2180 dso->binary_type = DSO_BINARY_TYPE__KALLSYMS;
2181 dso__set_long_name(dso, DSO__NAME_KALLSYMS, false);
2182 map__fixup_start(map);
2183 map__fixup_end(map);
2189 static int dso__load_guest_kernel_sym(struct dso *dso, struct map *map)
2192 const char *kallsyms_filename;
2193 struct machine *machine = maps__machine(map__kmaps(map));
2194 char path[PATH_MAX];
2196 if (machine->kallsyms_filename) {
2197 kallsyms_filename = machine->kallsyms_filename;
2198 } else if (machine__is_default_guest(machine)) {
2200 * if the user specified a vmlinux filename, use it and only
2201 * it, reporting errors to the user if it cannot be used.
2202 * Or use file guest_kallsyms inputted by user on commandline
2204 if (symbol_conf.default_guest_vmlinux_name != NULL) {
2205 err = dso__load_vmlinux(dso, map,
2206 symbol_conf.default_guest_vmlinux_name,
2211 kallsyms_filename = symbol_conf.default_guest_kallsyms;
2212 if (!kallsyms_filename)
2215 sprintf(path, "%s/proc/kallsyms", machine->root_dir);
2216 kallsyms_filename = path;
2219 err = dso__load_kallsyms(dso, kallsyms_filename, map);
2221 pr_debug("Using %s for symbols\n", kallsyms_filename);
2222 if (err > 0 && !dso__is_kcore(dso)) {
2223 dso->binary_type = DSO_BINARY_TYPE__GUEST_KALLSYMS;
2224 dso__set_long_name(dso, machine->mmap_name, false);
2225 map__fixup_start(map);
2226 map__fixup_end(map);
2232 static void vmlinux_path__exit(void)
2234 while (--vmlinux_path__nr_entries >= 0)
2235 zfree(&vmlinux_path[vmlinux_path__nr_entries]);
2236 vmlinux_path__nr_entries = 0;
2238 zfree(&vmlinux_path);
2241 static const char * const vmlinux_paths[] = {
2246 static const char * const vmlinux_paths_upd[] = {
2248 "/usr/lib/debug/boot/vmlinux-%s",
2249 "/lib/modules/%s/build/vmlinux",
2250 "/usr/lib/debug/lib/modules/%s/vmlinux",
2251 "/usr/lib/debug/boot/vmlinux-%s.debug"
2254 static int vmlinux_path__add(const char *new_entry)
2256 vmlinux_path[vmlinux_path__nr_entries] = strdup(new_entry);
2257 if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
2259 ++vmlinux_path__nr_entries;
2264 static int vmlinux_path__init(struct perf_env *env)
2268 char *kernel_version;
2271 vmlinux_path = malloc(sizeof(char *) * (ARRAY_SIZE(vmlinux_paths) +
2272 ARRAY_SIZE(vmlinux_paths_upd)));
2273 if (vmlinux_path == NULL)
2276 for (i = 0; i < ARRAY_SIZE(vmlinux_paths); i++)
2277 if (vmlinux_path__add(vmlinux_paths[i]) < 0)
2280 /* only try kernel version if no symfs was given */
2281 if (symbol_conf.symfs[0] != 0)
2285 kernel_version = env->os_release;
2287 if (uname(&uts) < 0)
2290 kernel_version = uts.release;
2293 for (i = 0; i < ARRAY_SIZE(vmlinux_paths_upd); i++) {
2294 snprintf(bf, sizeof(bf), vmlinux_paths_upd[i], kernel_version);
2295 if (vmlinux_path__add(bf) < 0)
2302 vmlinux_path__exit();
2306 int setup_list(struct strlist **list, const char *list_str,
2307 const char *list_name)
2309 if (list_str == NULL)
2312 *list = strlist__new(list_str, NULL);
2314 pr_err("problems parsing %s list\n", list_name);
2318 symbol_conf.has_filter = true;
2322 int setup_intlist(struct intlist **list, const char *list_str,
2323 const char *list_name)
2325 if (list_str == NULL)
2328 *list = intlist__new(list_str);
2330 pr_err("problems parsing %s list\n", list_name);
2336 static int setup_addrlist(struct intlist **addr_list, struct strlist *sym_list)
2338 struct str_node *pos, *tmp;
2344 *addr_list = intlist__new(NULL);
2348 strlist__for_each_entry_safe(pos, tmp, sym_list) {
2350 val = strtoul(pos->s, &sep, 16);
2351 if (errno || (sep == pos->s))
2355 end = pos->s + strlen(pos->s) - 1;
2356 while (end >= sep && isspace(*end))
2363 err = intlist__add(*addr_list, val);
2367 strlist__remove(sym_list, pos);
2372 intlist__delete(*addr_list);
2379 static bool symbol__read_kptr_restrict(void)
2382 FILE *fp = fopen("/proc/sys/kernel/kptr_restrict", "r");
2387 if (fgets(line, sizeof(line), fp) != NULL)
2388 value = perf_cap__capable(CAP_SYSLOG) ?
2395 /* Per kernel/kallsyms.c:
2396 * we also restrict when perf_event_paranoid > 1 w/o CAP_SYSLOG
2398 if (perf_event_paranoid() > 1 && !perf_cap__capable(CAP_SYSLOG))
2404 int symbol__annotation_init(void)
2406 if (symbol_conf.init_annotation)
2409 if (symbol_conf.initialized) {
2410 pr_err("Annotation needs to be init before symbol__init()\n");
2414 symbol_conf.priv_size += sizeof(struct annotation);
2415 symbol_conf.init_annotation = true;
2419 int symbol__init(struct perf_env *env)
2423 if (symbol_conf.initialized)
2426 symbol_conf.priv_size = PERF_ALIGN(symbol_conf.priv_size, sizeof(u64));
2430 if (symbol_conf.try_vmlinux_path && vmlinux_path__init(env) < 0)
2433 if (symbol_conf.field_sep && *symbol_conf.field_sep == '.') {
2434 pr_err("'.' is the only non valid --field-separator argument\n");
2438 if (setup_list(&symbol_conf.dso_list,
2439 symbol_conf.dso_list_str, "dso") < 0)
2442 if (setup_list(&symbol_conf.comm_list,
2443 symbol_conf.comm_list_str, "comm") < 0)
2444 goto out_free_dso_list;
2446 if (setup_intlist(&symbol_conf.pid_list,
2447 symbol_conf.pid_list_str, "pid") < 0)
2448 goto out_free_comm_list;
2450 if (setup_intlist(&symbol_conf.tid_list,
2451 symbol_conf.tid_list_str, "tid") < 0)
2452 goto out_free_pid_list;
2454 if (setup_list(&symbol_conf.sym_list,
2455 symbol_conf.sym_list_str, "symbol") < 0)
2456 goto out_free_tid_list;
2458 if (symbol_conf.sym_list &&
2459 setup_addrlist(&symbol_conf.addr_list, symbol_conf.sym_list) < 0)
2460 goto out_free_sym_list;
2462 if (setup_list(&symbol_conf.bt_stop_list,
2463 symbol_conf.bt_stop_list_str, "symbol") < 0)
2464 goto out_free_sym_list;
2467 * A path to symbols of "/" is identical to ""
2468 * reset here for simplicity.
2470 symfs = realpath(symbol_conf.symfs, NULL);
2472 symfs = symbol_conf.symfs;
2473 if (strcmp(symfs, "/") == 0)
2474 symbol_conf.symfs = "";
2475 if (symfs != symbol_conf.symfs)
2476 free((void *)symfs);
2478 symbol_conf.kptr_restrict = symbol__read_kptr_restrict();
2480 symbol_conf.initialized = true;
2484 strlist__delete(symbol_conf.sym_list);
2485 intlist__delete(symbol_conf.addr_list);
2487 intlist__delete(symbol_conf.tid_list);
2489 intlist__delete(symbol_conf.pid_list);
2491 strlist__delete(symbol_conf.comm_list);
2493 strlist__delete(symbol_conf.dso_list);
2497 void symbol__exit(void)
2499 if (!symbol_conf.initialized)
2501 strlist__delete(symbol_conf.bt_stop_list);
2502 strlist__delete(symbol_conf.sym_list);
2503 strlist__delete(symbol_conf.dso_list);
2504 strlist__delete(symbol_conf.comm_list);
2505 intlist__delete(symbol_conf.tid_list);
2506 intlist__delete(symbol_conf.pid_list);
2507 intlist__delete(symbol_conf.addr_list);
2508 vmlinux_path__exit();
2509 symbol_conf.sym_list = symbol_conf.dso_list = symbol_conf.comm_list = NULL;
2510 symbol_conf.bt_stop_list = NULL;
2511 symbol_conf.initialized = false;
2514 int symbol__config_symfs(const struct option *opt __maybe_unused,
2515 const char *dir, int unset __maybe_unused)
2520 symbol_conf.symfs = strdup(dir);
2521 if (symbol_conf.symfs == NULL)
2524 /* skip the locally configured cache if a symfs is given, and
2525 * config buildid dir to symfs/.debug
2527 ret = asprintf(&bf, "%s/%s", dir, ".debug");
2531 set_buildid_dir(bf);
2537 struct mem_info *mem_info__get(struct mem_info *mi)
2540 refcount_inc(&mi->refcnt);
2544 void mem_info__put(struct mem_info *mi)
2546 if (mi && refcount_dec_and_test(&mi->refcnt)) {
2547 addr_map_symbol__exit(&mi->iaddr);
2548 addr_map_symbol__exit(&mi->daddr);
2553 struct mem_info *mem_info__new(void)
2555 struct mem_info *mi = zalloc(sizeof(*mi));
2558 refcount_set(&mi->refcnt, 1);
2563 * Checks that user supplied symbol kernel files are accessible because
2564 * the default mechanism for accessing elf files fails silently. i.e. if
2565 * debug syms for a build ID aren't found perf carries on normally. When
2566 * they are user supplied we should assume that the user doesn't want to
2569 int symbol__validate_sym_arguments(void)
2571 if (symbol_conf.vmlinux_name &&
2572 access(symbol_conf.vmlinux_name, R_OK)) {
2573 pr_err("Invalid file: %s\n", symbol_conf.vmlinux_name);
2576 if (symbol_conf.kallsyms_name &&
2577 access(symbol_conf.kallsyms_name, R_OK)) {
2578 pr_err("Invalid file: %s\n", symbol_conf.kallsyms_name);