1 // SPDX-License-Identifier: GPL-2.0 2 #include <dirent.h> 3 #include <errno.h> 4 #include <stdlib.h> 5 #include <stdio.h> 6 #include <string.h> 7 #include <linux/kernel.h> 8 #include <linux/mman.h> 9 #include <sys/types.h> 10 #include <sys/stat.h> 11 #include <sys/param.h> 12 #include <fcntl.h> 13 #include <unistd.h> 14 #include <inttypes.h> 15 #include "annotate.h" 16 #include "build-id.h" 17 #include "util.h" 18 #include "debug.h" 19 #include "machine.h" 20 #include "symbol.h" 21 #include "strlist.h" 22 #include "intlist.h" 23 #include "namespaces.h" 24 #include "header.h" 25 #include "path.h" 26 #include "sane_ctype.h" 27 28 #include <elf.h> 29 #include <limits.h> 30 #include <symbol/kallsyms.h> 31 #include <sys/utsname.h> 32 33 static int dso__load_kernel_sym(struct dso *dso, struct map *map); 34 static int dso__load_guest_kernel_sym(struct dso *dso, struct map *map); 35 static bool symbol__is_idle(const char *name); 36 37 int vmlinux_path__nr_entries; 38 char **vmlinux_path; 39 40 struct symbol_conf symbol_conf = { 41 .use_modules = true, 42 .try_vmlinux_path = true, 43 .annotate_src = true, 44 .demangle = true, 45 .demangle_kernel = false, 46 .cumulate_callchain = true, 47 .show_hist_headers = true, 48 .symfs = "", 49 .event_group = true, 50 .inline_name = true, 51 }; 52 53 static enum dso_binary_type binary_type_symtab[] = { 54 DSO_BINARY_TYPE__KALLSYMS, 55 DSO_BINARY_TYPE__GUEST_KALLSYMS, 56 DSO_BINARY_TYPE__JAVA_JIT, 57 DSO_BINARY_TYPE__DEBUGLINK, 58 DSO_BINARY_TYPE__BUILD_ID_CACHE, 59 DSO_BINARY_TYPE__BUILD_ID_CACHE_DEBUGINFO, 60 DSO_BINARY_TYPE__FEDORA_DEBUGINFO, 61 DSO_BINARY_TYPE__UBUNTU_DEBUGINFO, 62 DSO_BINARY_TYPE__BUILDID_DEBUGINFO, 63 DSO_BINARY_TYPE__SYSTEM_PATH_DSO, 64 DSO_BINARY_TYPE__GUEST_KMODULE, 65 DSO_BINARY_TYPE__GUEST_KMODULE_COMP, 66 DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE, 67 DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP, 68 DSO_BINARY_TYPE__OPENEMBEDDED_DEBUGINFO, 69 DSO_BINARY_TYPE__NOT_FOUND, 70 }; 71 72 #define DSO_BINARY_TYPE__SYMTAB_CNT ARRAY_SIZE(binary_type_symtab) 73 74 static bool symbol_type__filter(char symbol_type) 75 { 76 symbol_type = toupper(symbol_type); 77 return symbol_type == 'T' || symbol_type == 'W' || symbol_type == 'D'; 78 } 79 80 static int prefix_underscores_count(const char *str) 81 { 82 const char *tail = str; 83 84 while (*tail == '_') 85 tail++; 86 87 return tail - str; 88 } 89 90 const char * __weak arch__normalize_symbol_name(const char *name) 91 { 92 return name; 93 } 94 95 int __weak arch__compare_symbol_names(const char *namea, const char *nameb) 96 { 97 return strcmp(namea, nameb); 98 } 99 100 int __weak arch__compare_symbol_names_n(const char *namea, const char *nameb, 101 unsigned int n) 102 { 103 return strncmp(namea, nameb, n); 104 } 105 106 int __weak arch__choose_best_symbol(struct symbol *syma, 107 struct symbol *symb __maybe_unused) 108 { 109 /* Avoid "SyS" kernel syscall aliases */ 110 if (strlen(syma->name) >= 3 && !strncmp(syma->name, "SyS", 3)) 111 return SYMBOL_B; 112 if (strlen(syma->name) >= 10 && !strncmp(syma->name, "compat_SyS", 10)) 113 return SYMBOL_B; 114 115 return SYMBOL_A; 116 } 117 118 static int choose_best_symbol(struct symbol *syma, struct symbol *symb) 119 { 120 s64 a; 121 s64 b; 122 size_t na, nb; 123 124 /* Prefer a symbol with non zero length */ 125 a = syma->end - syma->start; 126 b = symb->end - symb->start; 127 if ((b == 0) && (a > 0)) 128 return SYMBOL_A; 129 else if ((a == 0) && (b > 0)) 130 return SYMBOL_B; 131 132 /* Prefer a non weak symbol over a weak one */ 133 a = syma->binding == STB_WEAK; 134 b = symb->binding == STB_WEAK; 135 if (b && !a) 136 return SYMBOL_A; 137 if (a && !b) 138 return SYMBOL_B; 139 140 /* Prefer a global symbol over a non global one */ 141 a = syma->binding == STB_GLOBAL; 142 b = symb->binding == STB_GLOBAL; 143 if (a && !b) 144 return SYMBOL_A; 145 if (b && !a) 146 return SYMBOL_B; 147 148 /* Prefer a symbol with less underscores */ 149 a = prefix_underscores_count(syma->name); 150 b = prefix_underscores_count(symb->name); 151 if (b > a) 152 return SYMBOL_A; 153 else if (a > b) 154 return SYMBOL_B; 155 156 /* Choose the symbol with the longest name */ 157 na = strlen(syma->name); 158 nb = strlen(symb->name); 159 if (na > nb) 160 return SYMBOL_A; 161 else if (na < nb) 162 return SYMBOL_B; 163 164 return arch__choose_best_symbol(syma, symb); 165 } 166 167 void symbols__fixup_duplicate(struct rb_root *symbols) 168 { 169 struct rb_node *nd; 170 struct symbol *curr, *next; 171 172 if (symbol_conf.allow_aliases) 173 return; 174 175 nd = rb_first(symbols); 176 177 while (nd) { 178 curr = rb_entry(nd, struct symbol, rb_node); 179 again: 180 nd = rb_next(&curr->rb_node); 181 next = rb_entry(nd, struct symbol, rb_node); 182 183 if (!nd) 184 break; 185 186 if (curr->start != next->start) 187 continue; 188 189 if (choose_best_symbol(curr, next) == SYMBOL_A) { 190 rb_erase(&next->rb_node, symbols); 191 symbol__delete(next); 192 goto again; 193 } else { 194 nd = rb_next(&curr->rb_node); 195 rb_erase(&curr->rb_node, symbols); 196 symbol__delete(curr); 197 } 198 } 199 } 200 201 void symbols__fixup_end(struct rb_root *symbols) 202 { 203 struct rb_node *nd, *prevnd = rb_first(symbols); 204 struct symbol *curr, *prev; 205 206 if (prevnd == NULL) 207 return; 208 209 curr = rb_entry(prevnd, struct symbol, rb_node); 210 211 for (nd = rb_next(prevnd); nd; nd = rb_next(nd)) { 212 prev = curr; 213 curr = rb_entry(nd, struct symbol, rb_node); 214 215 if (prev->end == prev->start && prev->end != curr->start) 216 prev->end = curr->start; 217 } 218 219 /* Last entry */ 220 if (curr->end == curr->start) 221 curr->end = roundup(curr->start, 4096) + 4096; 222 } 223 224 void map_groups__fixup_end(struct map_groups *mg) 225 { 226 struct maps *maps = &mg->maps; 227 struct map *next, *curr; 228 229 down_write(&maps->lock); 230 231 curr = maps__first(maps); 232 if (curr == NULL) 233 goto out_unlock; 234 235 for (next = map__next(curr); next; next = map__next(curr)) { 236 if (!curr->end) 237 curr->end = next->start; 238 curr = next; 239 } 240 241 /* 242 * We still haven't the actual symbols, so guess the 243 * last map final address. 244 */ 245 if (!curr->end) 246 curr->end = ~0ULL; 247 248 out_unlock: 249 up_write(&maps->lock); 250 } 251 252 struct symbol *symbol__new(u64 start, u64 len, u8 binding, u8 type, const char *name) 253 { 254 size_t namelen = strlen(name) + 1; 255 struct symbol *sym = calloc(1, (symbol_conf.priv_size + 256 sizeof(*sym) + namelen)); 257 if (sym == NULL) 258 return NULL; 259 260 if (symbol_conf.priv_size) { 261 if (symbol_conf.init_annotation) { 262 struct annotation *notes = (void *)sym; 263 pthread_mutex_init(¬es->lock, NULL); 264 } 265 sym = ((void *)sym) + symbol_conf.priv_size; 266 } 267 268 sym->start = start; 269 sym->end = len ? start + len : start; 270 sym->type = type; 271 sym->binding = binding; 272 sym->namelen = namelen - 1; 273 274 pr_debug4("%s: %s %#" PRIx64 "-%#" PRIx64 "\n", 275 __func__, name, start, sym->end); 276 memcpy(sym->name, name, namelen); 277 278 return sym; 279 } 280 281 void symbol__delete(struct symbol *sym) 282 { 283 free(((void *)sym) - symbol_conf.priv_size); 284 } 285 286 void symbols__delete(struct rb_root *symbols) 287 { 288 struct symbol *pos; 289 struct rb_node *next = rb_first(symbols); 290 291 while (next) { 292 pos = rb_entry(next, struct symbol, rb_node); 293 next = rb_next(&pos->rb_node); 294 rb_erase(&pos->rb_node, symbols); 295 symbol__delete(pos); 296 } 297 } 298 299 void __symbols__insert(struct rb_root *symbols, struct symbol *sym, bool kernel) 300 { 301 struct rb_node **p = &symbols->rb_node; 302 struct rb_node *parent = NULL; 303 const u64 ip = sym->start; 304 struct symbol *s; 305 306 if (kernel) { 307 const char *name = sym->name; 308 /* 309 * ppc64 uses function descriptors and appends a '.' to the 310 * start of every instruction address. Remove it. 311 */ 312 if (name[0] == '.') 313 name++; 314 sym->idle = symbol__is_idle(name); 315 } 316 317 while (*p != NULL) { 318 parent = *p; 319 s = rb_entry(parent, struct symbol, rb_node); 320 if (ip < s->start) 321 p = &(*p)->rb_left; 322 else 323 p = &(*p)->rb_right; 324 } 325 rb_link_node(&sym->rb_node, parent, p); 326 rb_insert_color(&sym->rb_node, symbols); 327 } 328 329 void symbols__insert(struct rb_root *symbols, struct symbol *sym) 330 { 331 __symbols__insert(symbols, sym, false); 332 } 333 334 static struct symbol *symbols__find(struct rb_root *symbols, u64 ip) 335 { 336 struct rb_node *n; 337 338 if (symbols == NULL) 339 return NULL; 340 341 n = symbols->rb_node; 342 343 while (n) { 344 struct symbol *s = rb_entry(n, struct symbol, rb_node); 345 346 if (ip < s->start) 347 n = n->rb_left; 348 else if (ip > s->end || (ip == s->end && ip != s->start)) 349 n = n->rb_right; 350 else 351 return s; 352 } 353 354 return NULL; 355 } 356 357 static struct symbol *symbols__first(struct rb_root *symbols) 358 { 359 struct rb_node *n = rb_first(symbols); 360 361 if (n) 362 return rb_entry(n, struct symbol, rb_node); 363 364 return NULL; 365 } 366 367 static struct symbol *symbols__last(struct rb_root *symbols) 368 { 369 struct rb_node *n = rb_last(symbols); 370 371 if (n) 372 return rb_entry(n, struct symbol, rb_node); 373 374 return NULL; 375 } 376 377 static struct symbol *symbols__next(struct symbol *sym) 378 { 379 struct rb_node *n = rb_next(&sym->rb_node); 380 381 if (n) 382 return rb_entry(n, struct symbol, rb_node); 383 384 return NULL; 385 } 386 387 static void symbols__insert_by_name(struct rb_root *symbols, struct symbol *sym) 388 { 389 struct rb_node **p = &symbols->rb_node; 390 struct rb_node *parent = NULL; 391 struct symbol_name_rb_node *symn, *s; 392 393 symn = container_of(sym, struct symbol_name_rb_node, sym); 394 395 while (*p != NULL) { 396 parent = *p; 397 s = rb_entry(parent, struct symbol_name_rb_node, rb_node); 398 if (strcmp(sym->name, s->sym.name) < 0) 399 p = &(*p)->rb_left; 400 else 401 p = &(*p)->rb_right; 402 } 403 rb_link_node(&symn->rb_node, parent, p); 404 rb_insert_color(&symn->rb_node, symbols); 405 } 406 407 static void symbols__sort_by_name(struct rb_root *symbols, 408 struct rb_root *source) 409 { 410 struct rb_node *nd; 411 412 for (nd = rb_first(source); nd; nd = rb_next(nd)) { 413 struct symbol *pos = rb_entry(nd, struct symbol, rb_node); 414 symbols__insert_by_name(symbols, pos); 415 } 416 } 417 418 int symbol__match_symbol_name(const char *name, const char *str, 419 enum symbol_tag_include includes) 420 { 421 const char *versioning; 422 423 if (includes == SYMBOL_TAG_INCLUDE__DEFAULT_ONLY && 424 (versioning = strstr(name, "@@"))) { 425 int len = strlen(str); 426 427 if (len < versioning - name) 428 len = versioning - name; 429 430 return arch__compare_symbol_names_n(name, str, len); 431 } else 432 return arch__compare_symbol_names(name, str); 433 } 434 435 static struct symbol *symbols__find_by_name(struct rb_root *symbols, 436 const char *name, 437 enum symbol_tag_include includes) 438 { 439 struct rb_node *n; 440 struct symbol_name_rb_node *s = NULL; 441 442 if (symbols == NULL) 443 return NULL; 444 445 n = symbols->rb_node; 446 447 while (n) { 448 int cmp; 449 450 s = rb_entry(n, struct symbol_name_rb_node, rb_node); 451 cmp = symbol__match_symbol_name(s->sym.name, name, includes); 452 453 if (cmp > 0) 454 n = n->rb_left; 455 else if (cmp < 0) 456 n = n->rb_right; 457 else 458 break; 459 } 460 461 if (n == NULL) 462 return NULL; 463 464 if (includes != SYMBOL_TAG_INCLUDE__DEFAULT_ONLY) 465 /* return first symbol that has same name (if any) */ 466 for (n = rb_prev(n); n; n = rb_prev(n)) { 467 struct symbol_name_rb_node *tmp; 468 469 tmp = rb_entry(n, struct symbol_name_rb_node, rb_node); 470 if (arch__compare_symbol_names(tmp->sym.name, s->sym.name)) 471 break; 472 473 s = tmp; 474 } 475 476 return &s->sym; 477 } 478 479 void dso__reset_find_symbol_cache(struct dso *dso) 480 { 481 dso->last_find_result.addr = 0; 482 dso->last_find_result.symbol = NULL; 483 } 484 485 void dso__insert_symbol(struct dso *dso, struct symbol *sym) 486 { 487 __symbols__insert(&dso->symbols, sym, dso->kernel); 488 489 /* update the symbol cache if necessary */ 490 if (dso->last_find_result.addr >= sym->start && 491 (dso->last_find_result.addr < sym->end || 492 sym->start == sym->end)) { 493 dso->last_find_result.symbol = sym; 494 } 495 } 496 497 struct symbol *dso__find_symbol(struct dso *dso, u64 addr) 498 { 499 if (dso->last_find_result.addr != addr || dso->last_find_result.symbol == NULL) { 500 dso->last_find_result.addr = addr; 501 dso->last_find_result.symbol = symbols__find(&dso->symbols, addr); 502 } 503 504 return dso->last_find_result.symbol; 505 } 506 507 struct symbol *dso__first_symbol(struct dso *dso) 508 { 509 return symbols__first(&dso->symbols); 510 } 511 512 struct symbol *dso__last_symbol(struct dso *dso) 513 { 514 return symbols__last(&dso->symbols); 515 } 516 517 struct symbol *dso__next_symbol(struct symbol *sym) 518 { 519 return symbols__next(sym); 520 } 521 522 struct symbol *symbol__next_by_name(struct symbol *sym) 523 { 524 struct symbol_name_rb_node *s = container_of(sym, struct symbol_name_rb_node, sym); 525 struct rb_node *n = rb_next(&s->rb_node); 526 527 return n ? &rb_entry(n, struct symbol_name_rb_node, rb_node)->sym : NULL; 528 } 529 530 /* 531 * Returns first symbol that matched with @name. 532 */ 533 struct symbol *dso__find_symbol_by_name(struct dso *dso, const char *name) 534 { 535 struct symbol *s = symbols__find_by_name(&dso->symbol_names, name, 536 SYMBOL_TAG_INCLUDE__NONE); 537 if (!s) 538 s = symbols__find_by_name(&dso->symbol_names, name, 539 SYMBOL_TAG_INCLUDE__DEFAULT_ONLY); 540 return s; 541 } 542 543 void dso__sort_by_name(struct dso *dso) 544 { 545 dso__set_sorted_by_name(dso); 546 return symbols__sort_by_name(&dso->symbol_names, &dso->symbols); 547 } 548 549 int modules__parse(const char *filename, void *arg, 550 int (*process_module)(void *arg, const char *name, 551 u64 start, u64 size)) 552 { 553 char *line = NULL; 554 size_t n; 555 FILE *file; 556 int err = 0; 557 558 file = fopen(filename, "r"); 559 if (file == NULL) 560 return -1; 561 562 while (1) { 563 char name[PATH_MAX]; 564 u64 start, size; 565 char *sep, *endptr; 566 ssize_t line_len; 567 568 line_len = getline(&line, &n, file); 569 if (line_len < 0) { 570 if (feof(file)) 571 break; 572 err = -1; 573 goto out; 574 } 575 576 if (!line) { 577 err = -1; 578 goto out; 579 } 580 581 line[--line_len] = '\0'; /* \n */ 582 583 sep = strrchr(line, 'x'); 584 if (sep == NULL) 585 continue; 586 587 hex2u64(sep + 1, &start); 588 589 sep = strchr(line, ' '); 590 if (sep == NULL) 591 continue; 592 593 *sep = '\0'; 594 595 scnprintf(name, sizeof(name), "[%s]", line); 596 597 size = strtoul(sep + 1, &endptr, 0); 598 if (*endptr != ' ' && *endptr != '\t') 599 continue; 600 601 err = process_module(arg, name, start, size); 602 if (err) 603 break; 604 } 605 out: 606 free(line); 607 fclose(file); 608 return err; 609 } 610 611 /* 612 * These are symbols in the kernel image, so make sure that 613 * sym is from a kernel DSO. 614 */ 615 static bool symbol__is_idle(const char *name) 616 { 617 const char * const idle_symbols[] = { 618 "cpu_idle", 619 "cpu_startup_entry", 620 "intel_idle", 621 "default_idle", 622 "native_safe_halt", 623 "enter_idle", 624 "exit_idle", 625 "mwait_idle", 626 "mwait_idle_with_hints", 627 "poll_idle", 628 "ppc64_runlatch_off", 629 "pseries_dedicated_idle_sleep", 630 NULL 631 }; 632 int i; 633 634 for (i = 0; idle_symbols[i]; i++) { 635 if (!strcmp(idle_symbols[i], name)) 636 return true; 637 } 638 639 return false; 640 } 641 642 static int map__process_kallsym_symbol(void *arg, const char *name, 643 char type, u64 start) 644 { 645 struct symbol *sym; 646 struct dso *dso = arg; 647 struct rb_root *root = &dso->symbols; 648 649 if (!symbol_type__filter(type)) 650 return 0; 651 652 /* 653 * module symbols are not sorted so we add all 654 * symbols, setting length to 0, and rely on 655 * symbols__fixup_end() to fix it up. 656 */ 657 sym = symbol__new(start, 0, kallsyms2elf_binding(type), kallsyms2elf_type(type), name); 658 if (sym == NULL) 659 return -ENOMEM; 660 /* 661 * We will pass the symbols to the filter later, in 662 * map__split_kallsyms, when we have split the maps per module 663 */ 664 __symbols__insert(root, sym, !strchr(name, '[')); 665 666 return 0; 667 } 668 669 /* 670 * Loads the function entries in /proc/kallsyms into kernel_map->dso, 671 * so that we can in the next step set the symbol ->end address and then 672 * call kernel_maps__split_kallsyms. 673 */ 674 static int dso__load_all_kallsyms(struct dso *dso, const char *filename) 675 { 676 return kallsyms__parse(filename, dso, map__process_kallsym_symbol); 677 } 678 679 static int map_groups__split_kallsyms_for_kcore(struct map_groups *kmaps, struct dso *dso) 680 { 681 struct map *curr_map; 682 struct symbol *pos; 683 int count = 0; 684 struct rb_root old_root = dso->symbols; 685 struct rb_root *root = &dso->symbols; 686 struct rb_node *next = rb_first(root); 687 688 if (!kmaps) 689 return -1; 690 691 *root = RB_ROOT; 692 693 while (next) { 694 char *module; 695 696 pos = rb_entry(next, struct symbol, rb_node); 697 next = rb_next(&pos->rb_node); 698 699 rb_erase_init(&pos->rb_node, &old_root); 700 701 module = strchr(pos->name, '\t'); 702 if (module) 703 *module = '\0'; 704 705 curr_map = map_groups__find(kmaps, pos->start); 706 707 if (!curr_map) { 708 symbol__delete(pos); 709 continue; 710 } 711 712 pos->start -= curr_map->start - curr_map->pgoff; 713 if (pos->end) 714 pos->end -= curr_map->start - curr_map->pgoff; 715 symbols__insert(&curr_map->dso->symbols, pos); 716 ++count; 717 } 718 719 /* Symbols have been adjusted */ 720 dso->adjust_symbols = 1; 721 722 return count; 723 } 724 725 /* 726 * Split the symbols into maps, making sure there are no overlaps, i.e. the 727 * kernel range is broken in several maps, named [kernel].N, as we don't have 728 * the original ELF section names vmlinux have. 729 */ 730 static int map_groups__split_kallsyms(struct map_groups *kmaps, struct dso *dso, u64 delta, 731 struct map *initial_map) 732 { 733 struct machine *machine; 734 struct map *curr_map = initial_map; 735 struct symbol *pos; 736 int count = 0, moved = 0; 737 struct rb_root *root = &dso->symbols; 738 struct rb_node *next = rb_first(root); 739 int kernel_range = 0; 740 bool x86_64; 741 742 if (!kmaps) 743 return -1; 744 745 machine = kmaps->machine; 746 747 x86_64 = machine__is(machine, "x86_64"); 748 749 while (next) { 750 char *module; 751 752 pos = rb_entry(next, struct symbol, rb_node); 753 next = rb_next(&pos->rb_node); 754 755 module = strchr(pos->name, '\t'); 756 if (module) { 757 if (!symbol_conf.use_modules) 758 goto discard_symbol; 759 760 *module++ = '\0'; 761 762 if (strcmp(curr_map->dso->short_name, module)) { 763 if (curr_map != initial_map && 764 dso->kernel == DSO_TYPE_GUEST_KERNEL && 765 machine__is_default_guest(machine)) { 766 /* 767 * We assume all symbols of a module are 768 * continuous in * kallsyms, so curr_map 769 * points to a module and all its 770 * symbols are in its kmap. Mark it as 771 * loaded. 772 */ 773 dso__set_loaded(curr_map->dso); 774 } 775 776 curr_map = map_groups__find_by_name(kmaps, module); 777 if (curr_map == NULL) { 778 pr_debug("%s/proc/{kallsyms,modules} " 779 "inconsistency while looking " 780 "for \"%s\" module!\n", 781 machine->root_dir, module); 782 curr_map = initial_map; 783 goto discard_symbol; 784 } 785 786 if (curr_map->dso->loaded && 787 !machine__is_default_guest(machine)) 788 goto discard_symbol; 789 } 790 /* 791 * So that we look just like we get from .ko files, 792 * i.e. not prelinked, relative to initial_map->start. 793 */ 794 pos->start = curr_map->map_ip(curr_map, pos->start); 795 pos->end = curr_map->map_ip(curr_map, pos->end); 796 } else if (x86_64 && is_entry_trampoline(pos->name)) { 797 /* 798 * These symbols are not needed anymore since the 799 * trampoline maps refer to the text section and it's 800 * symbols instead. Avoid having to deal with 801 * relocations, and the assumption that the first symbol 802 * is the start of kernel text, by simply removing the 803 * symbols at this point. 804 */ 805 goto discard_symbol; 806 } else if (curr_map != initial_map) { 807 char dso_name[PATH_MAX]; 808 struct dso *ndso; 809 810 if (delta) { 811 /* Kernel was relocated at boot time */ 812 pos->start -= delta; 813 pos->end -= delta; 814 } 815 816 if (count == 0) { 817 curr_map = initial_map; 818 goto add_symbol; 819 } 820 821 if (dso->kernel == DSO_TYPE_GUEST_KERNEL) 822 snprintf(dso_name, sizeof(dso_name), 823 "[guest.kernel].%d", 824 kernel_range++); 825 else 826 snprintf(dso_name, sizeof(dso_name), 827 "[kernel].%d", 828 kernel_range++); 829 830 ndso = dso__new(dso_name); 831 if (ndso == NULL) 832 return -1; 833 834 ndso->kernel = dso->kernel; 835 836 curr_map = map__new2(pos->start, ndso); 837 if (curr_map == NULL) { 838 dso__put(ndso); 839 return -1; 840 } 841 842 curr_map->map_ip = curr_map->unmap_ip = identity__map_ip; 843 map_groups__insert(kmaps, curr_map); 844 ++kernel_range; 845 } else if (delta) { 846 /* Kernel was relocated at boot time */ 847 pos->start -= delta; 848 pos->end -= delta; 849 } 850 add_symbol: 851 if (curr_map != initial_map) { 852 rb_erase(&pos->rb_node, root); 853 symbols__insert(&curr_map->dso->symbols, pos); 854 ++moved; 855 } else 856 ++count; 857 858 continue; 859 discard_symbol: 860 rb_erase(&pos->rb_node, root); 861 symbol__delete(pos); 862 } 863 864 if (curr_map != initial_map && 865 dso->kernel == DSO_TYPE_GUEST_KERNEL && 866 machine__is_default_guest(kmaps->machine)) { 867 dso__set_loaded(curr_map->dso); 868 } 869 870 return count + moved; 871 } 872 873 bool symbol__restricted_filename(const char *filename, 874 const char *restricted_filename) 875 { 876 bool restricted = false; 877 878 if (symbol_conf.kptr_restrict) { 879 char *r = realpath(filename, NULL); 880 881 if (r != NULL) { 882 restricted = strcmp(r, restricted_filename) == 0; 883 free(r); 884 return restricted; 885 } 886 } 887 888 return restricted; 889 } 890 891 struct module_info { 892 struct rb_node rb_node; 893 char *name; 894 u64 start; 895 }; 896 897 static void add_module(struct module_info *mi, struct rb_root *modules) 898 { 899 struct rb_node **p = &modules->rb_node; 900 struct rb_node *parent = NULL; 901 struct module_info *m; 902 903 while (*p != NULL) { 904 parent = *p; 905 m = rb_entry(parent, struct module_info, rb_node); 906 if (strcmp(mi->name, m->name) < 0) 907 p = &(*p)->rb_left; 908 else 909 p = &(*p)->rb_right; 910 } 911 rb_link_node(&mi->rb_node, parent, p); 912 rb_insert_color(&mi->rb_node, modules); 913 } 914 915 static void delete_modules(struct rb_root *modules) 916 { 917 struct module_info *mi; 918 struct rb_node *next = rb_first(modules); 919 920 while (next) { 921 mi = rb_entry(next, struct module_info, rb_node); 922 next = rb_next(&mi->rb_node); 923 rb_erase(&mi->rb_node, modules); 924 zfree(&mi->name); 925 free(mi); 926 } 927 } 928 929 static struct module_info *find_module(const char *name, 930 struct rb_root *modules) 931 { 932 struct rb_node *n = modules->rb_node; 933 934 while (n) { 935 struct module_info *m; 936 int cmp; 937 938 m = rb_entry(n, struct module_info, rb_node); 939 cmp = strcmp(name, m->name); 940 if (cmp < 0) 941 n = n->rb_left; 942 else if (cmp > 0) 943 n = n->rb_right; 944 else 945 return m; 946 } 947 948 return NULL; 949 } 950 951 static int __read_proc_modules(void *arg, const char *name, u64 start, 952 u64 size __maybe_unused) 953 { 954 struct rb_root *modules = arg; 955 struct module_info *mi; 956 957 mi = zalloc(sizeof(struct module_info)); 958 if (!mi) 959 return -ENOMEM; 960 961 mi->name = strdup(name); 962 mi->start = start; 963 964 if (!mi->name) { 965 free(mi); 966 return -ENOMEM; 967 } 968 969 add_module(mi, modules); 970 971 return 0; 972 } 973 974 static int read_proc_modules(const char *filename, struct rb_root *modules) 975 { 976 if (symbol__restricted_filename(filename, "/proc/modules")) 977 return -1; 978 979 if (modules__parse(filename, modules, __read_proc_modules)) { 980 delete_modules(modules); 981 return -1; 982 } 983 984 return 0; 985 } 986 987 int compare_proc_modules(const char *from, const char *to) 988 { 989 struct rb_root from_modules = RB_ROOT; 990 struct rb_root to_modules = RB_ROOT; 991 struct rb_node *from_node, *to_node; 992 struct module_info *from_m, *to_m; 993 int ret = -1; 994 995 if (read_proc_modules(from, &from_modules)) 996 return -1; 997 998 if (read_proc_modules(to, &to_modules)) 999 goto out_delete_from; 1000 1001 from_node = rb_first(&from_modules); 1002 to_node = rb_first(&to_modules); 1003 while (from_node) { 1004 if (!to_node) 1005 break; 1006 1007 from_m = rb_entry(from_node, struct module_info, rb_node); 1008 to_m = rb_entry(to_node, struct module_info, rb_node); 1009 1010 if (from_m->start != to_m->start || 1011 strcmp(from_m->name, to_m->name)) 1012 break; 1013 1014 from_node = rb_next(from_node); 1015 to_node = rb_next(to_node); 1016 } 1017 1018 if (!from_node && !to_node) 1019 ret = 0; 1020 1021 delete_modules(&to_modules); 1022 out_delete_from: 1023 delete_modules(&from_modules); 1024 1025 return ret; 1026 } 1027 1028 struct map *map_groups__first(struct map_groups *mg) 1029 { 1030 return maps__first(&mg->maps); 1031 } 1032 1033 static int do_validate_kcore_modules(const char *filename, 1034 struct map_groups *kmaps) 1035 { 1036 struct rb_root modules = RB_ROOT; 1037 struct map *old_map; 1038 int err; 1039 1040 err = read_proc_modules(filename, &modules); 1041 if (err) 1042 return err; 1043 1044 old_map = map_groups__first(kmaps); 1045 while (old_map) { 1046 struct map *next = map_groups__next(old_map); 1047 struct module_info *mi; 1048 1049 if (!__map__is_kmodule(old_map)) { 1050 old_map = next; 1051 continue; 1052 } 1053 1054 /* Module must be in memory at the same address */ 1055 mi = find_module(old_map->dso->short_name, &modules); 1056 if (!mi || mi->start != old_map->start) { 1057 err = -EINVAL; 1058 goto out; 1059 } 1060 1061 old_map = next; 1062 } 1063 out: 1064 delete_modules(&modules); 1065 return err; 1066 } 1067 1068 /* 1069 * If kallsyms is referenced by name then we look for filename in the same 1070 * directory. 1071 */ 1072 static bool filename_from_kallsyms_filename(char *filename, 1073 const char *base_name, 1074 const char *kallsyms_filename) 1075 { 1076 char *name; 1077 1078 strcpy(filename, kallsyms_filename); 1079 name = strrchr(filename, '/'); 1080 if (!name) 1081 return false; 1082 1083 name += 1; 1084 1085 if (!strcmp(name, "kallsyms")) { 1086 strcpy(name, base_name); 1087 return true; 1088 } 1089 1090 return false; 1091 } 1092 1093 static int validate_kcore_modules(const char *kallsyms_filename, 1094 struct map *map) 1095 { 1096 struct map_groups *kmaps = map__kmaps(map); 1097 char modules_filename[PATH_MAX]; 1098 1099 if (!kmaps) 1100 return -EINVAL; 1101 1102 if (!filename_from_kallsyms_filename(modules_filename, "modules", 1103 kallsyms_filename)) 1104 return -EINVAL; 1105 1106 if (do_validate_kcore_modules(modules_filename, kmaps)) 1107 return -EINVAL; 1108 1109 return 0; 1110 } 1111 1112 static int validate_kcore_addresses(const char *kallsyms_filename, 1113 struct map *map) 1114 { 1115 struct kmap *kmap = map__kmap(map); 1116 1117 if (!kmap) 1118 return -EINVAL; 1119 1120 if (kmap->ref_reloc_sym && kmap->ref_reloc_sym->name) { 1121 u64 start; 1122 1123 if (kallsyms__get_function_start(kallsyms_filename, 1124 kmap->ref_reloc_sym->name, &start)) 1125 return -ENOENT; 1126 if (start != kmap->ref_reloc_sym->addr) 1127 return -EINVAL; 1128 } 1129 1130 return validate_kcore_modules(kallsyms_filename, map); 1131 } 1132 1133 struct kcore_mapfn_data { 1134 struct dso *dso; 1135 struct list_head maps; 1136 }; 1137 1138 static int kcore_mapfn(u64 start, u64 len, u64 pgoff, void *data) 1139 { 1140 struct kcore_mapfn_data *md = data; 1141 struct map *map; 1142 1143 map = map__new2(start, md->dso); 1144 if (map == NULL) 1145 return -ENOMEM; 1146 1147 map->end = map->start + len; 1148 map->pgoff = pgoff; 1149 1150 list_add(&map->node, &md->maps); 1151 1152 return 0; 1153 } 1154 1155 static int dso__load_kcore(struct dso *dso, struct map *map, 1156 const char *kallsyms_filename) 1157 { 1158 struct map_groups *kmaps = map__kmaps(map); 1159 struct kcore_mapfn_data md; 1160 struct map *old_map, *new_map, *replacement_map = NULL; 1161 struct machine *machine; 1162 bool is_64_bit; 1163 int err, fd; 1164 char kcore_filename[PATH_MAX]; 1165 u64 stext; 1166 1167 if (!kmaps) 1168 return -EINVAL; 1169 1170 machine = kmaps->machine; 1171 1172 /* This function requires that the map is the kernel map */ 1173 if (!__map__is_kernel(map)) 1174 return -EINVAL; 1175 1176 if (!filename_from_kallsyms_filename(kcore_filename, "kcore", 1177 kallsyms_filename)) 1178 return -EINVAL; 1179 1180 /* Modules and kernel must be present at their original addresses */ 1181 if (validate_kcore_addresses(kallsyms_filename, map)) 1182 return -EINVAL; 1183 1184 md.dso = dso; 1185 INIT_LIST_HEAD(&md.maps); 1186 1187 fd = open(kcore_filename, O_RDONLY); 1188 if (fd < 0) { 1189 pr_debug("Failed to open %s. Note /proc/kcore requires CAP_SYS_RAWIO capability to access.\n", 1190 kcore_filename); 1191 return -EINVAL; 1192 } 1193 1194 /* Read new maps into temporary lists */ 1195 err = file__read_maps(fd, map->prot & PROT_EXEC, kcore_mapfn, &md, 1196 &is_64_bit); 1197 if (err) 1198 goto out_err; 1199 dso->is_64_bit = is_64_bit; 1200 1201 if (list_empty(&md.maps)) { 1202 err = -EINVAL; 1203 goto out_err; 1204 } 1205 1206 /* Remove old maps */ 1207 old_map = map_groups__first(kmaps); 1208 while (old_map) { 1209 struct map *next = map_groups__next(old_map); 1210 1211 if (old_map != map) 1212 map_groups__remove(kmaps, old_map); 1213 old_map = next; 1214 } 1215 machine->trampolines_mapped = false; 1216 1217 /* Find the kernel map using the '_stext' symbol */ 1218 if (!kallsyms__get_function_start(kallsyms_filename, "_stext", &stext)) { 1219 list_for_each_entry(new_map, &md.maps, node) { 1220 if (stext >= new_map->start && stext < new_map->end) { 1221 replacement_map = new_map; 1222 break; 1223 } 1224 } 1225 } 1226 1227 if (!replacement_map) 1228 replacement_map = list_entry(md.maps.next, struct map, node); 1229 1230 /* Add new maps */ 1231 while (!list_empty(&md.maps)) { 1232 new_map = list_entry(md.maps.next, struct map, node); 1233 list_del_init(&new_map->node); 1234 if (new_map == replacement_map) { 1235 map->start = new_map->start; 1236 map->end = new_map->end; 1237 map->pgoff = new_map->pgoff; 1238 map->map_ip = new_map->map_ip; 1239 map->unmap_ip = new_map->unmap_ip; 1240 /* Ensure maps are correctly ordered */ 1241 map__get(map); 1242 map_groups__remove(kmaps, map); 1243 map_groups__insert(kmaps, map); 1244 map__put(map); 1245 } else { 1246 map_groups__insert(kmaps, new_map); 1247 } 1248 1249 map__put(new_map); 1250 } 1251 1252 if (machine__is(machine, "x86_64")) { 1253 u64 addr; 1254 1255 /* 1256 * If one of the corresponding symbols is there, assume the 1257 * entry trampoline maps are too. 1258 */ 1259 if (!kallsyms__get_function_start(kallsyms_filename, 1260 ENTRY_TRAMPOLINE_NAME, 1261 &addr)) 1262 machine->trampolines_mapped = true; 1263 } 1264 1265 /* 1266 * Set the data type and long name so that kcore can be read via 1267 * dso__data_read_addr(). 1268 */ 1269 if (dso->kernel == DSO_TYPE_GUEST_KERNEL) 1270 dso->binary_type = DSO_BINARY_TYPE__GUEST_KCORE; 1271 else 1272 dso->binary_type = DSO_BINARY_TYPE__KCORE; 1273 dso__set_long_name(dso, strdup(kcore_filename), true); 1274 1275 close(fd); 1276 1277 if (map->prot & PROT_EXEC) 1278 pr_debug("Using %s for kernel object code\n", kcore_filename); 1279 else 1280 pr_debug("Using %s for kernel data\n", kcore_filename); 1281 1282 return 0; 1283 1284 out_err: 1285 while (!list_empty(&md.maps)) { 1286 map = list_entry(md.maps.next, struct map, node); 1287 list_del_init(&map->node); 1288 map__put(map); 1289 } 1290 close(fd); 1291 return -EINVAL; 1292 } 1293 1294 /* 1295 * If the kernel is relocated at boot time, kallsyms won't match. Compute the 1296 * delta based on the relocation reference symbol. 1297 */ 1298 static int kallsyms__delta(struct kmap *kmap, const char *filename, u64 *delta) 1299 { 1300 u64 addr; 1301 1302 if (!kmap->ref_reloc_sym || !kmap->ref_reloc_sym->name) 1303 return 0; 1304 1305 if (kallsyms__get_function_start(filename, kmap->ref_reloc_sym->name, &addr)) 1306 return -1; 1307 1308 *delta = addr - kmap->ref_reloc_sym->addr; 1309 return 0; 1310 } 1311 1312 int __dso__load_kallsyms(struct dso *dso, const char *filename, 1313 struct map *map, bool no_kcore) 1314 { 1315 struct kmap *kmap = map__kmap(map); 1316 u64 delta = 0; 1317 1318 if (symbol__restricted_filename(filename, "/proc/kallsyms")) 1319 return -1; 1320 1321 if (!kmap || !kmap->kmaps) 1322 return -1; 1323 1324 if (dso__load_all_kallsyms(dso, filename) < 0) 1325 return -1; 1326 1327 if (kallsyms__delta(kmap, filename, &delta)) 1328 return -1; 1329 1330 symbols__fixup_end(&dso->symbols); 1331 symbols__fixup_duplicate(&dso->symbols); 1332 1333 if (dso->kernel == DSO_TYPE_GUEST_KERNEL) 1334 dso->symtab_type = DSO_BINARY_TYPE__GUEST_KALLSYMS; 1335 else 1336 dso->symtab_type = DSO_BINARY_TYPE__KALLSYMS; 1337 1338 if (!no_kcore && !dso__load_kcore(dso, map, filename)) 1339 return map_groups__split_kallsyms_for_kcore(kmap->kmaps, dso); 1340 else 1341 return map_groups__split_kallsyms(kmap->kmaps, dso, delta, map); 1342 } 1343 1344 int dso__load_kallsyms(struct dso *dso, const char *filename, 1345 struct map *map) 1346 { 1347 return __dso__load_kallsyms(dso, filename, map, false); 1348 } 1349 1350 static int dso__load_perf_map(const char *map_path, struct dso *dso) 1351 { 1352 char *line = NULL; 1353 size_t n; 1354 FILE *file; 1355 int nr_syms = 0; 1356 1357 file = fopen(map_path, "r"); 1358 if (file == NULL) 1359 goto out_failure; 1360 1361 while (!feof(file)) { 1362 u64 start, size; 1363 struct symbol *sym; 1364 int line_len, len; 1365 1366 line_len = getline(&line, &n, file); 1367 if (line_len < 0) 1368 break; 1369 1370 if (!line) 1371 goto out_failure; 1372 1373 line[--line_len] = '\0'; /* \n */ 1374 1375 len = hex2u64(line, &start); 1376 1377 len++; 1378 if (len + 2 >= line_len) 1379 continue; 1380 1381 len += hex2u64(line + len, &size); 1382 1383 len++; 1384 if (len + 2 >= line_len) 1385 continue; 1386 1387 sym = symbol__new(start, size, STB_GLOBAL, STT_FUNC, line + len); 1388 1389 if (sym == NULL) 1390 goto out_delete_line; 1391 1392 symbols__insert(&dso->symbols, sym); 1393 nr_syms++; 1394 } 1395 1396 free(line); 1397 fclose(file); 1398 1399 return nr_syms; 1400 1401 out_delete_line: 1402 free(line); 1403 out_failure: 1404 return -1; 1405 } 1406 1407 static bool dso__is_compatible_symtab_type(struct dso *dso, bool kmod, 1408 enum dso_binary_type type) 1409 { 1410 switch (type) { 1411 case DSO_BINARY_TYPE__JAVA_JIT: 1412 case DSO_BINARY_TYPE__DEBUGLINK: 1413 case DSO_BINARY_TYPE__SYSTEM_PATH_DSO: 1414 case DSO_BINARY_TYPE__FEDORA_DEBUGINFO: 1415 case DSO_BINARY_TYPE__UBUNTU_DEBUGINFO: 1416 case DSO_BINARY_TYPE__BUILDID_DEBUGINFO: 1417 case DSO_BINARY_TYPE__OPENEMBEDDED_DEBUGINFO: 1418 return !kmod && dso->kernel == DSO_TYPE_USER; 1419 1420 case DSO_BINARY_TYPE__KALLSYMS: 1421 case DSO_BINARY_TYPE__VMLINUX: 1422 case DSO_BINARY_TYPE__KCORE: 1423 return dso->kernel == DSO_TYPE_KERNEL; 1424 1425 case DSO_BINARY_TYPE__GUEST_KALLSYMS: 1426 case DSO_BINARY_TYPE__GUEST_VMLINUX: 1427 case DSO_BINARY_TYPE__GUEST_KCORE: 1428 return dso->kernel == DSO_TYPE_GUEST_KERNEL; 1429 1430 case DSO_BINARY_TYPE__GUEST_KMODULE: 1431 case DSO_BINARY_TYPE__GUEST_KMODULE_COMP: 1432 case DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE: 1433 case DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP: 1434 /* 1435 * kernel modules know their symtab type - it's set when 1436 * creating a module dso in machine__findnew_module_map(). 1437 */ 1438 return kmod && dso->symtab_type == type; 1439 1440 case DSO_BINARY_TYPE__BUILD_ID_CACHE: 1441 case DSO_BINARY_TYPE__BUILD_ID_CACHE_DEBUGINFO: 1442 return true; 1443 1444 case DSO_BINARY_TYPE__NOT_FOUND: 1445 default: 1446 return false; 1447 } 1448 } 1449 1450 /* Checks for the existence of the perf-<pid>.map file in two different 1451 * locations. First, if the process is a separate mount namespace, check in 1452 * that namespace using the pid of the innermost pid namespace. If's not in a 1453 * namespace, or the file can't be found there, try in the mount namespace of 1454 * the tracing process using our view of its pid. 1455 */ 1456 static int dso__find_perf_map(char *filebuf, size_t bufsz, 1457 struct nsinfo **nsip) 1458 { 1459 struct nscookie nsc; 1460 struct nsinfo *nsi; 1461 struct nsinfo *nnsi; 1462 int rc = -1; 1463 1464 nsi = *nsip; 1465 1466 if (nsi->need_setns) { 1467 snprintf(filebuf, bufsz, "/tmp/perf-%d.map", nsi->nstgid); 1468 nsinfo__mountns_enter(nsi, &nsc); 1469 rc = access(filebuf, R_OK); 1470 nsinfo__mountns_exit(&nsc); 1471 if (rc == 0) 1472 return rc; 1473 } 1474 1475 nnsi = nsinfo__copy(nsi); 1476 if (nnsi) { 1477 nsinfo__put(nsi); 1478 1479 nnsi->need_setns = false; 1480 snprintf(filebuf, bufsz, "/tmp/perf-%d.map", nnsi->tgid); 1481 *nsip = nnsi; 1482 rc = 0; 1483 } 1484 1485 return rc; 1486 } 1487 1488 int dso__load(struct dso *dso, struct map *map) 1489 { 1490 char *name; 1491 int ret = -1; 1492 u_int i; 1493 struct machine *machine; 1494 char *root_dir = (char *) ""; 1495 int ss_pos = 0; 1496 struct symsrc ss_[2]; 1497 struct symsrc *syms_ss = NULL, *runtime_ss = NULL; 1498 bool kmod; 1499 bool perfmap; 1500 unsigned char build_id[BUILD_ID_SIZE]; 1501 struct nscookie nsc; 1502 char newmapname[PATH_MAX]; 1503 const char *map_path = dso->long_name; 1504 1505 perfmap = strncmp(dso->name, "/tmp/perf-", 10) == 0; 1506 if (perfmap) { 1507 if (dso->nsinfo && (dso__find_perf_map(newmapname, 1508 sizeof(newmapname), &dso->nsinfo) == 0)) { 1509 map_path = newmapname; 1510 } 1511 } 1512 1513 nsinfo__mountns_enter(dso->nsinfo, &nsc); 1514 pthread_mutex_lock(&dso->lock); 1515 1516 /* check again under the dso->lock */ 1517 if (dso__loaded(dso)) { 1518 ret = 1; 1519 goto out; 1520 } 1521 1522 if (map->groups && map->groups->machine) 1523 machine = map->groups->machine; 1524 else 1525 machine = NULL; 1526 1527 if (dso->kernel) { 1528 if (dso->kernel == DSO_TYPE_KERNEL) 1529 ret = dso__load_kernel_sym(dso, map); 1530 else if (dso->kernel == DSO_TYPE_GUEST_KERNEL) 1531 ret = dso__load_guest_kernel_sym(dso, map); 1532 1533 if (machine__is(machine, "x86_64")) 1534 machine__map_x86_64_entry_trampolines(machine, dso); 1535 goto out; 1536 } 1537 1538 dso->adjust_symbols = 0; 1539 1540 if (perfmap) { 1541 struct stat st; 1542 1543 if (lstat(map_path, &st) < 0) 1544 goto out; 1545 1546 if (!symbol_conf.force && st.st_uid && (st.st_uid != geteuid())) { 1547 pr_warning("File %s not owned by current user or root, " 1548 "ignoring it (use -f to override).\n", map_path); 1549 goto out; 1550 } 1551 1552 ret = dso__load_perf_map(map_path, dso); 1553 dso->symtab_type = ret > 0 ? DSO_BINARY_TYPE__JAVA_JIT : 1554 DSO_BINARY_TYPE__NOT_FOUND; 1555 goto out; 1556 } 1557 1558 if (machine) 1559 root_dir = machine->root_dir; 1560 1561 name = malloc(PATH_MAX); 1562 if (!name) 1563 goto out; 1564 1565 kmod = dso->symtab_type == DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE || 1566 dso->symtab_type == DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP || 1567 dso->symtab_type == DSO_BINARY_TYPE__GUEST_KMODULE || 1568 dso->symtab_type == DSO_BINARY_TYPE__GUEST_KMODULE_COMP; 1569 1570 1571 /* 1572 * Read the build id if possible. This is required for 1573 * DSO_BINARY_TYPE__BUILDID_DEBUGINFO to work 1574 */ 1575 if (!dso->has_build_id && 1576 is_regular_file(dso->long_name)) { 1577 __symbol__join_symfs(name, PATH_MAX, dso->long_name); 1578 if (filename__read_build_id(name, build_id, BUILD_ID_SIZE) > 0) 1579 dso__set_build_id(dso, build_id); 1580 } 1581 1582 /* 1583 * Iterate over candidate debug images. 1584 * Keep track of "interesting" ones (those which have a symtab, dynsym, 1585 * and/or opd section) for processing. 1586 */ 1587 for (i = 0; i < DSO_BINARY_TYPE__SYMTAB_CNT; i++) { 1588 struct symsrc *ss = &ss_[ss_pos]; 1589 bool next_slot = false; 1590 bool is_reg; 1591 bool nsexit; 1592 int sirc = -1; 1593 1594 enum dso_binary_type symtab_type = binary_type_symtab[i]; 1595 1596 nsexit = (symtab_type == DSO_BINARY_TYPE__BUILD_ID_CACHE || 1597 symtab_type == DSO_BINARY_TYPE__BUILD_ID_CACHE_DEBUGINFO); 1598 1599 if (!dso__is_compatible_symtab_type(dso, kmod, symtab_type)) 1600 continue; 1601 1602 if (dso__read_binary_type_filename(dso, symtab_type, 1603 root_dir, name, PATH_MAX)) 1604 continue; 1605 1606 if (nsexit) 1607 nsinfo__mountns_exit(&nsc); 1608 1609 is_reg = is_regular_file(name); 1610 if (is_reg) 1611 sirc = symsrc__init(ss, dso, name, symtab_type); 1612 1613 if (nsexit) 1614 nsinfo__mountns_enter(dso->nsinfo, &nsc); 1615 1616 if (!is_reg || sirc < 0) 1617 continue; 1618 1619 if (!syms_ss && symsrc__has_symtab(ss)) { 1620 syms_ss = ss; 1621 next_slot = true; 1622 if (!dso->symsrc_filename) 1623 dso->symsrc_filename = strdup(name); 1624 } 1625 1626 if (!runtime_ss && symsrc__possibly_runtime(ss)) { 1627 runtime_ss = ss; 1628 next_slot = true; 1629 } 1630 1631 if (next_slot) { 1632 ss_pos++; 1633 1634 if (syms_ss && runtime_ss) 1635 break; 1636 } else { 1637 symsrc__destroy(ss); 1638 } 1639 1640 } 1641 1642 if (!runtime_ss && !syms_ss) 1643 goto out_free; 1644 1645 if (runtime_ss && !syms_ss) { 1646 syms_ss = runtime_ss; 1647 } 1648 1649 /* We'll have to hope for the best */ 1650 if (!runtime_ss && syms_ss) 1651 runtime_ss = syms_ss; 1652 1653 if (syms_ss) 1654 ret = dso__load_sym(dso, map, syms_ss, runtime_ss, kmod); 1655 else 1656 ret = -1; 1657 1658 if (ret > 0) { 1659 int nr_plt; 1660 1661 nr_plt = dso__synthesize_plt_symbols(dso, runtime_ss); 1662 if (nr_plt > 0) 1663 ret += nr_plt; 1664 } 1665 1666 for (; ss_pos > 0; ss_pos--) 1667 symsrc__destroy(&ss_[ss_pos - 1]); 1668 out_free: 1669 free(name); 1670 if (ret < 0 && strstr(dso->name, " (deleted)") != NULL) 1671 ret = 0; 1672 out: 1673 dso__set_loaded(dso); 1674 pthread_mutex_unlock(&dso->lock); 1675 nsinfo__mountns_exit(&nsc); 1676 1677 return ret; 1678 } 1679 1680 struct map *map_groups__find_by_name(struct map_groups *mg, const char *name) 1681 { 1682 struct maps *maps = &mg->maps; 1683 struct map *map; 1684 1685 down_read(&maps->lock); 1686 1687 for (map = maps__first(maps); map; map = map__next(map)) { 1688 if (map->dso && strcmp(map->dso->short_name, name) == 0) 1689 goto out_unlock; 1690 } 1691 1692 map = NULL; 1693 1694 out_unlock: 1695 up_read(&maps->lock); 1696 return map; 1697 } 1698 1699 int dso__load_vmlinux(struct dso *dso, struct map *map, 1700 const char *vmlinux, bool vmlinux_allocated) 1701 { 1702 int err = -1; 1703 struct symsrc ss; 1704 char symfs_vmlinux[PATH_MAX]; 1705 enum dso_binary_type symtab_type; 1706 1707 if (vmlinux[0] == '/') 1708 snprintf(symfs_vmlinux, sizeof(symfs_vmlinux), "%s", vmlinux); 1709 else 1710 symbol__join_symfs(symfs_vmlinux, vmlinux); 1711 1712 if (dso->kernel == DSO_TYPE_GUEST_KERNEL) 1713 symtab_type = DSO_BINARY_TYPE__GUEST_VMLINUX; 1714 else 1715 symtab_type = DSO_BINARY_TYPE__VMLINUX; 1716 1717 if (symsrc__init(&ss, dso, symfs_vmlinux, symtab_type)) 1718 return -1; 1719 1720 err = dso__load_sym(dso, map, &ss, &ss, 0); 1721 symsrc__destroy(&ss); 1722 1723 if (err > 0) { 1724 if (dso->kernel == DSO_TYPE_GUEST_KERNEL) 1725 dso->binary_type = DSO_BINARY_TYPE__GUEST_VMLINUX; 1726 else 1727 dso->binary_type = DSO_BINARY_TYPE__VMLINUX; 1728 dso__set_long_name(dso, vmlinux, vmlinux_allocated); 1729 dso__set_loaded(dso); 1730 pr_debug("Using %s for symbols\n", symfs_vmlinux); 1731 } 1732 1733 return err; 1734 } 1735 1736 int dso__load_vmlinux_path(struct dso *dso, struct map *map) 1737 { 1738 int i, err = 0; 1739 char *filename = NULL; 1740 1741 pr_debug("Looking at the vmlinux_path (%d entries long)\n", 1742 vmlinux_path__nr_entries + 1); 1743 1744 for (i = 0; i < vmlinux_path__nr_entries; ++i) { 1745 err = dso__load_vmlinux(dso, map, vmlinux_path[i], false); 1746 if (err > 0) 1747 goto out; 1748 } 1749 1750 if (!symbol_conf.ignore_vmlinux_buildid) 1751 filename = dso__build_id_filename(dso, NULL, 0, false); 1752 if (filename != NULL) { 1753 err = dso__load_vmlinux(dso, map, filename, true); 1754 if (err > 0) 1755 goto out; 1756 free(filename); 1757 } 1758 out: 1759 return err; 1760 } 1761 1762 static bool visible_dir_filter(const char *name, struct dirent *d) 1763 { 1764 if (d->d_type != DT_DIR) 1765 return false; 1766 return lsdir_no_dot_filter(name, d); 1767 } 1768 1769 static int find_matching_kcore(struct map *map, char *dir, size_t dir_sz) 1770 { 1771 char kallsyms_filename[PATH_MAX]; 1772 int ret = -1; 1773 struct strlist *dirs; 1774 struct str_node *nd; 1775 1776 dirs = lsdir(dir, visible_dir_filter); 1777 if (!dirs) 1778 return -1; 1779 1780 strlist__for_each_entry(nd, dirs) { 1781 scnprintf(kallsyms_filename, sizeof(kallsyms_filename), 1782 "%s/%s/kallsyms", dir, nd->s); 1783 if (!validate_kcore_addresses(kallsyms_filename, map)) { 1784 strlcpy(dir, kallsyms_filename, dir_sz); 1785 ret = 0; 1786 break; 1787 } 1788 } 1789 1790 strlist__delete(dirs); 1791 1792 return ret; 1793 } 1794 1795 /* 1796 * Use open(O_RDONLY) to check readability directly instead of access(R_OK) 1797 * since access(R_OK) only checks with real UID/GID but open() use effective 1798 * UID/GID and actual capabilities (e.g. /proc/kcore requires CAP_SYS_RAWIO). 1799 */ 1800 static bool filename__readable(const char *file) 1801 { 1802 int fd = open(file, O_RDONLY); 1803 if (fd < 0) 1804 return false; 1805 close(fd); 1806 return true; 1807 } 1808 1809 static char *dso__find_kallsyms(struct dso *dso, struct map *map) 1810 { 1811 u8 host_build_id[BUILD_ID_SIZE]; 1812 char sbuild_id[SBUILD_ID_SIZE]; 1813 bool is_host = false; 1814 char path[PATH_MAX]; 1815 1816 if (!dso->has_build_id) { 1817 /* 1818 * Last resort, if we don't have a build-id and couldn't find 1819 * any vmlinux file, try the running kernel kallsyms table. 1820 */ 1821 goto proc_kallsyms; 1822 } 1823 1824 if (sysfs__read_build_id("/sys/kernel/notes", host_build_id, 1825 sizeof(host_build_id)) == 0) 1826 is_host = dso__build_id_equal(dso, host_build_id); 1827 1828 /* Try a fast path for /proc/kallsyms if possible */ 1829 if (is_host) { 1830 /* 1831 * Do not check the build-id cache, unless we know we cannot use 1832 * /proc/kcore or module maps don't match to /proc/kallsyms. 1833 * To check readability of /proc/kcore, do not use access(R_OK) 1834 * since /proc/kcore requires CAP_SYS_RAWIO to read and access 1835 * can't check it. 1836 */ 1837 if (filename__readable("/proc/kcore") && 1838 !validate_kcore_addresses("/proc/kallsyms", map)) 1839 goto proc_kallsyms; 1840 } 1841 1842 build_id__sprintf(dso->build_id, sizeof(dso->build_id), sbuild_id); 1843 1844 /* Find kallsyms in build-id cache with kcore */ 1845 scnprintf(path, sizeof(path), "%s/%s/%s", 1846 buildid_dir, DSO__NAME_KCORE, sbuild_id); 1847 1848 if (!find_matching_kcore(map, path, sizeof(path))) 1849 return strdup(path); 1850 1851 /* Use current /proc/kallsyms if possible */ 1852 if (is_host) { 1853 proc_kallsyms: 1854 return strdup("/proc/kallsyms"); 1855 } 1856 1857 /* Finally, find a cache of kallsyms */ 1858 if (!build_id_cache__kallsyms_path(sbuild_id, path, sizeof(path))) { 1859 pr_err("No kallsyms or vmlinux with build-id %s was found\n", 1860 sbuild_id); 1861 return NULL; 1862 } 1863 1864 return strdup(path); 1865 } 1866 1867 static int dso__load_kernel_sym(struct dso *dso, struct map *map) 1868 { 1869 int err; 1870 const char *kallsyms_filename = NULL; 1871 char *kallsyms_allocated_filename = NULL; 1872 /* 1873 * Step 1: if the user specified a kallsyms or vmlinux filename, use 1874 * it and only it, reporting errors to the user if it cannot be used. 1875 * 1876 * For instance, try to analyse an ARM perf.data file _without_ a 1877 * build-id, or if the user specifies the wrong path to the right 1878 * vmlinux file, obviously we can't fallback to another vmlinux (a 1879 * x86_86 one, on the machine where analysis is being performed, say), 1880 * or worse, /proc/kallsyms. 1881 * 1882 * If the specified file _has_ a build-id and there is a build-id 1883 * section in the perf.data file, we will still do the expected 1884 * validation in dso__load_vmlinux and will bail out if they don't 1885 * match. 1886 */ 1887 if (symbol_conf.kallsyms_name != NULL) { 1888 kallsyms_filename = symbol_conf.kallsyms_name; 1889 goto do_kallsyms; 1890 } 1891 1892 if (!symbol_conf.ignore_vmlinux && symbol_conf.vmlinux_name != NULL) { 1893 return dso__load_vmlinux(dso, map, symbol_conf.vmlinux_name, false); 1894 } 1895 1896 if (!symbol_conf.ignore_vmlinux && vmlinux_path != NULL) { 1897 err = dso__load_vmlinux_path(dso, map); 1898 if (err > 0) 1899 return err; 1900 } 1901 1902 /* do not try local files if a symfs was given */ 1903 if (symbol_conf.symfs[0] != 0) 1904 return -1; 1905 1906 kallsyms_allocated_filename = dso__find_kallsyms(dso, map); 1907 if (!kallsyms_allocated_filename) 1908 return -1; 1909 1910 kallsyms_filename = kallsyms_allocated_filename; 1911 1912 do_kallsyms: 1913 err = dso__load_kallsyms(dso, kallsyms_filename, map); 1914 if (err > 0) 1915 pr_debug("Using %s for symbols\n", kallsyms_filename); 1916 free(kallsyms_allocated_filename); 1917 1918 if (err > 0 && !dso__is_kcore(dso)) { 1919 dso->binary_type = DSO_BINARY_TYPE__KALLSYMS; 1920 dso__set_long_name(dso, DSO__NAME_KALLSYMS, false); 1921 map__fixup_start(map); 1922 map__fixup_end(map); 1923 } 1924 1925 return err; 1926 } 1927 1928 static int dso__load_guest_kernel_sym(struct dso *dso, struct map *map) 1929 { 1930 int err; 1931 const char *kallsyms_filename = NULL; 1932 struct machine *machine; 1933 char path[PATH_MAX]; 1934 1935 if (!map->groups) { 1936 pr_debug("Guest kernel map hasn't the point to groups\n"); 1937 return -1; 1938 } 1939 machine = map->groups->machine; 1940 1941 if (machine__is_default_guest(machine)) { 1942 /* 1943 * if the user specified a vmlinux filename, use it and only 1944 * it, reporting errors to the user if it cannot be used. 1945 * Or use file guest_kallsyms inputted by user on commandline 1946 */ 1947 if (symbol_conf.default_guest_vmlinux_name != NULL) { 1948 err = dso__load_vmlinux(dso, map, 1949 symbol_conf.default_guest_vmlinux_name, 1950 false); 1951 return err; 1952 } 1953 1954 kallsyms_filename = symbol_conf.default_guest_kallsyms; 1955 if (!kallsyms_filename) 1956 return -1; 1957 } else { 1958 sprintf(path, "%s/proc/kallsyms", machine->root_dir); 1959 kallsyms_filename = path; 1960 } 1961 1962 err = dso__load_kallsyms(dso, kallsyms_filename, map); 1963 if (err > 0) 1964 pr_debug("Using %s for symbols\n", kallsyms_filename); 1965 if (err > 0 && !dso__is_kcore(dso)) { 1966 dso->binary_type = DSO_BINARY_TYPE__GUEST_KALLSYMS; 1967 dso__set_long_name(dso, machine->mmap_name, false); 1968 map__fixup_start(map); 1969 map__fixup_end(map); 1970 } 1971 1972 return err; 1973 } 1974 1975 static void vmlinux_path__exit(void) 1976 { 1977 while (--vmlinux_path__nr_entries >= 0) 1978 zfree(&vmlinux_path[vmlinux_path__nr_entries]); 1979 vmlinux_path__nr_entries = 0; 1980 1981 zfree(&vmlinux_path); 1982 } 1983 1984 static const char * const vmlinux_paths[] = { 1985 "vmlinux", 1986 "/boot/vmlinux" 1987 }; 1988 1989 static const char * const vmlinux_paths_upd[] = { 1990 "/boot/vmlinux-%s", 1991 "/usr/lib/debug/boot/vmlinux-%s", 1992 "/lib/modules/%s/build/vmlinux", 1993 "/usr/lib/debug/lib/modules/%s/vmlinux", 1994 "/usr/lib/debug/boot/vmlinux-%s.debug" 1995 }; 1996 1997 static int vmlinux_path__add(const char *new_entry) 1998 { 1999 vmlinux_path[vmlinux_path__nr_entries] = strdup(new_entry); 2000 if (vmlinux_path[vmlinux_path__nr_entries] == NULL) 2001 return -1; 2002 ++vmlinux_path__nr_entries; 2003 2004 return 0; 2005 } 2006 2007 static int vmlinux_path__init(struct perf_env *env) 2008 { 2009 struct utsname uts; 2010 char bf[PATH_MAX]; 2011 char *kernel_version; 2012 unsigned int i; 2013 2014 vmlinux_path = malloc(sizeof(char *) * (ARRAY_SIZE(vmlinux_paths) + 2015 ARRAY_SIZE(vmlinux_paths_upd))); 2016 if (vmlinux_path == NULL) 2017 return -1; 2018 2019 for (i = 0; i < ARRAY_SIZE(vmlinux_paths); i++) 2020 if (vmlinux_path__add(vmlinux_paths[i]) < 0) 2021 goto out_fail; 2022 2023 /* only try kernel version if no symfs was given */ 2024 if (symbol_conf.symfs[0] != 0) 2025 return 0; 2026 2027 if (env) { 2028 kernel_version = env->os_release; 2029 } else { 2030 if (uname(&uts) < 0) 2031 goto out_fail; 2032 2033 kernel_version = uts.release; 2034 } 2035 2036 for (i = 0; i < ARRAY_SIZE(vmlinux_paths_upd); i++) { 2037 snprintf(bf, sizeof(bf), vmlinux_paths_upd[i], kernel_version); 2038 if (vmlinux_path__add(bf) < 0) 2039 goto out_fail; 2040 } 2041 2042 return 0; 2043 2044 out_fail: 2045 vmlinux_path__exit(); 2046 return -1; 2047 } 2048 2049 int setup_list(struct strlist **list, const char *list_str, 2050 const char *list_name) 2051 { 2052 if (list_str == NULL) 2053 return 0; 2054 2055 *list = strlist__new(list_str, NULL); 2056 if (!*list) { 2057 pr_err("problems parsing %s list\n", list_name); 2058 return -1; 2059 } 2060 2061 symbol_conf.has_filter = true; 2062 return 0; 2063 } 2064 2065 int setup_intlist(struct intlist **list, const char *list_str, 2066 const char *list_name) 2067 { 2068 if (list_str == NULL) 2069 return 0; 2070 2071 *list = intlist__new(list_str); 2072 if (!*list) { 2073 pr_err("problems parsing %s list\n", list_name); 2074 return -1; 2075 } 2076 return 0; 2077 } 2078 2079 static bool symbol__read_kptr_restrict(void) 2080 { 2081 bool value = false; 2082 FILE *fp = fopen("/proc/sys/kernel/kptr_restrict", "r"); 2083 2084 if (fp != NULL) { 2085 char line[8]; 2086 2087 if (fgets(line, sizeof(line), fp) != NULL) 2088 value = ((geteuid() != 0) || (getuid() != 0)) ? 2089 (atoi(line) != 0) : 2090 (atoi(line) == 2); 2091 2092 fclose(fp); 2093 } 2094 2095 return value; 2096 } 2097 2098 int symbol__annotation_init(void) 2099 { 2100 if (symbol_conf.init_annotation) 2101 return 0; 2102 2103 if (symbol_conf.initialized) { 2104 pr_err("Annotation needs to be init before symbol__init()\n"); 2105 return -1; 2106 } 2107 2108 symbol_conf.priv_size += sizeof(struct annotation); 2109 symbol_conf.init_annotation = true; 2110 return 0; 2111 } 2112 2113 int symbol__init(struct perf_env *env) 2114 { 2115 const char *symfs; 2116 2117 if (symbol_conf.initialized) 2118 return 0; 2119 2120 symbol_conf.priv_size = PERF_ALIGN(symbol_conf.priv_size, sizeof(u64)); 2121 2122 symbol__elf_init(); 2123 2124 if (symbol_conf.sort_by_name) 2125 symbol_conf.priv_size += (sizeof(struct symbol_name_rb_node) - 2126 sizeof(struct symbol)); 2127 2128 if (symbol_conf.try_vmlinux_path && vmlinux_path__init(env) < 0) 2129 return -1; 2130 2131 if (symbol_conf.field_sep && *symbol_conf.field_sep == '.') { 2132 pr_err("'.' is the only non valid --field-separator argument\n"); 2133 return -1; 2134 } 2135 2136 if (setup_list(&symbol_conf.dso_list, 2137 symbol_conf.dso_list_str, "dso") < 0) 2138 return -1; 2139 2140 if (setup_list(&symbol_conf.comm_list, 2141 symbol_conf.comm_list_str, "comm") < 0) 2142 goto out_free_dso_list; 2143 2144 if (setup_intlist(&symbol_conf.pid_list, 2145 symbol_conf.pid_list_str, "pid") < 0) 2146 goto out_free_comm_list; 2147 2148 if (setup_intlist(&symbol_conf.tid_list, 2149 symbol_conf.tid_list_str, "tid") < 0) 2150 goto out_free_pid_list; 2151 2152 if (setup_list(&symbol_conf.sym_list, 2153 symbol_conf.sym_list_str, "symbol") < 0) 2154 goto out_free_tid_list; 2155 2156 if (setup_list(&symbol_conf.bt_stop_list, 2157 symbol_conf.bt_stop_list_str, "symbol") < 0) 2158 goto out_free_sym_list; 2159 2160 /* 2161 * A path to symbols of "/" is identical to "" 2162 * reset here for simplicity. 2163 */ 2164 symfs = realpath(symbol_conf.symfs, NULL); 2165 if (symfs == NULL) 2166 symfs = symbol_conf.symfs; 2167 if (strcmp(symfs, "/") == 0) 2168 symbol_conf.symfs = ""; 2169 if (symfs != symbol_conf.symfs) 2170 free((void *)symfs); 2171 2172 symbol_conf.kptr_restrict = symbol__read_kptr_restrict(); 2173 2174 symbol_conf.initialized = true; 2175 return 0; 2176 2177 out_free_sym_list: 2178 strlist__delete(symbol_conf.sym_list); 2179 out_free_tid_list: 2180 intlist__delete(symbol_conf.tid_list); 2181 out_free_pid_list: 2182 intlist__delete(symbol_conf.pid_list); 2183 out_free_comm_list: 2184 strlist__delete(symbol_conf.comm_list); 2185 out_free_dso_list: 2186 strlist__delete(symbol_conf.dso_list); 2187 return -1; 2188 } 2189 2190 void symbol__exit(void) 2191 { 2192 if (!symbol_conf.initialized) 2193 return; 2194 strlist__delete(symbol_conf.bt_stop_list); 2195 strlist__delete(symbol_conf.sym_list); 2196 strlist__delete(symbol_conf.dso_list); 2197 strlist__delete(symbol_conf.comm_list); 2198 intlist__delete(symbol_conf.tid_list); 2199 intlist__delete(symbol_conf.pid_list); 2200 vmlinux_path__exit(); 2201 symbol_conf.sym_list = symbol_conf.dso_list = symbol_conf.comm_list = NULL; 2202 symbol_conf.bt_stop_list = NULL; 2203 symbol_conf.initialized = false; 2204 } 2205 2206 int symbol__config_symfs(const struct option *opt __maybe_unused, 2207 const char *dir, int unset __maybe_unused) 2208 { 2209 char *bf = NULL; 2210 int ret; 2211 2212 symbol_conf.symfs = strdup(dir); 2213 if (symbol_conf.symfs == NULL) 2214 return -ENOMEM; 2215 2216 /* skip the locally configured cache if a symfs is given, and 2217 * config buildid dir to symfs/.debug 2218 */ 2219 ret = asprintf(&bf, "%s/%s", dir, ".debug"); 2220 if (ret < 0) 2221 return -ENOMEM; 2222 2223 set_buildid_dir(bf); 2224 2225 free(bf); 2226 return 0; 2227 } 2228 2229 struct mem_info *mem_info__get(struct mem_info *mi) 2230 { 2231 if (mi) 2232 refcount_inc(&mi->refcnt); 2233 return mi; 2234 } 2235 2236 void mem_info__put(struct mem_info *mi) 2237 { 2238 if (mi && refcount_dec_and_test(&mi->refcnt)) 2239 free(mi); 2240 } 2241 2242 struct mem_info *mem_info__new(void) 2243 { 2244 struct mem_info *mi = zalloc(sizeof(*mi)); 2245 2246 if (mi) 2247 refcount_set(&mi->refcnt, 1); 2248 return mi; 2249 } 2250