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