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 "map.h" 21 #include "symbol.h" 22 #include "strlist.h" 23 #include "intlist.h" 24 #include "namespaces.h" 25 #include "header.h" 26 #include "path.h" 27 #include "sane_ctype.h" 28 29 #include <elf.h> 30 #include <limits.h> 31 #include <symbol/kallsyms.h> 32 #include <sys/utsname.h> 33 34 static int dso__load_kernel_sym(struct dso *dso, struct map *map); 35 static int dso__load_guest_kernel_sym(struct dso *dso, struct map *map); 36 static bool symbol__is_idle(const char *name); 37 38 int vmlinux_path__nr_entries; 39 char **vmlinux_path; 40 41 struct symbol_conf symbol_conf = { 42 .use_modules = true, 43 .try_vmlinux_path = 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' || symbol_type == 'B'; 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_cached *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_cached(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_cached(&next->rb_node, symbols); 191 symbol__delete(next); 192 goto again; 193 } else { 194 nd = rb_next(&curr->rb_node); 195 rb_erase_cached(&curr->rb_node, symbols); 196 symbol__delete(curr); 197 } 198 } 199 } 200 201 void symbols__fixup_end(struct rb_root_cached *symbols) 202 { 203 struct rb_node *nd, *prevnd = rb_first_cached(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_cached *symbols) 287 { 288 struct symbol *pos; 289 struct rb_node *next = rb_first_cached(symbols); 290 291 while (next) { 292 pos = rb_entry(next, struct symbol, rb_node); 293 next = rb_next(&pos->rb_node); 294 rb_erase_cached(&pos->rb_node, symbols); 295 symbol__delete(pos); 296 } 297 } 298 299 void __symbols__insert(struct rb_root_cached *symbols, 300 struct symbol *sym, bool kernel) 301 { 302 struct rb_node **p = &symbols->rb_root.rb_node; 303 struct rb_node *parent = NULL; 304 const u64 ip = sym->start; 305 struct symbol *s; 306 bool leftmost = true; 307 308 if (kernel) { 309 const char *name = sym->name; 310 /* 311 * ppc64 uses function descriptors and appends a '.' to the 312 * start of every instruction address. Remove it. 313 */ 314 if (name[0] == '.') 315 name++; 316 sym->idle = symbol__is_idle(name); 317 } 318 319 while (*p != NULL) { 320 parent = *p; 321 s = rb_entry(parent, struct symbol, rb_node); 322 if (ip < s->start) 323 p = &(*p)->rb_left; 324 else { 325 p = &(*p)->rb_right; 326 leftmost = false; 327 } 328 } 329 rb_link_node(&sym->rb_node, parent, p); 330 rb_insert_color_cached(&sym->rb_node, symbols, leftmost); 331 } 332 333 void symbols__insert(struct rb_root_cached *symbols, struct symbol *sym) 334 { 335 __symbols__insert(symbols, sym, false); 336 } 337 338 static struct symbol *symbols__find(struct rb_root_cached *symbols, u64 ip) 339 { 340 struct rb_node *n; 341 342 if (symbols == NULL) 343 return NULL; 344 345 n = symbols->rb_root.rb_node; 346 347 while (n) { 348 struct symbol *s = rb_entry(n, struct symbol, rb_node); 349 350 if (ip < s->start) 351 n = n->rb_left; 352 else if (ip > s->end || (ip == s->end && ip != s->start)) 353 n = n->rb_right; 354 else 355 return s; 356 } 357 358 return NULL; 359 } 360 361 static struct symbol *symbols__first(struct rb_root_cached *symbols) 362 { 363 struct rb_node *n = rb_first_cached(symbols); 364 365 if (n) 366 return rb_entry(n, struct symbol, rb_node); 367 368 return NULL; 369 } 370 371 static struct symbol *symbols__last(struct rb_root_cached *symbols) 372 { 373 struct rb_node *n = rb_last(&symbols->rb_root); 374 375 if (n) 376 return rb_entry(n, struct symbol, rb_node); 377 378 return NULL; 379 } 380 381 static struct symbol *symbols__next(struct symbol *sym) 382 { 383 struct rb_node *n = rb_next(&sym->rb_node); 384 385 if (n) 386 return rb_entry(n, struct symbol, rb_node); 387 388 return NULL; 389 } 390 391 static void symbols__insert_by_name(struct rb_root_cached *symbols, struct symbol *sym) 392 { 393 struct rb_node **p = &symbols->rb_root.rb_node; 394 struct rb_node *parent = NULL; 395 struct symbol_name_rb_node *symn, *s; 396 bool leftmost = true; 397 398 symn = container_of(sym, struct symbol_name_rb_node, sym); 399 400 while (*p != NULL) { 401 parent = *p; 402 s = rb_entry(parent, struct symbol_name_rb_node, rb_node); 403 if (strcmp(sym->name, s->sym.name) < 0) 404 p = &(*p)->rb_left; 405 else { 406 p = &(*p)->rb_right; 407 leftmost = false; 408 } 409 } 410 rb_link_node(&symn->rb_node, parent, p); 411 rb_insert_color_cached(&symn->rb_node, symbols, leftmost); 412 } 413 414 static void symbols__sort_by_name(struct rb_root_cached *symbols, 415 struct rb_root_cached *source) 416 { 417 struct rb_node *nd; 418 419 for (nd = rb_first_cached(source); nd; nd = rb_next(nd)) { 420 struct symbol *pos = rb_entry(nd, struct symbol, rb_node); 421 symbols__insert_by_name(symbols, pos); 422 } 423 } 424 425 int symbol__match_symbol_name(const char *name, const char *str, 426 enum symbol_tag_include includes) 427 { 428 const char *versioning; 429 430 if (includes == SYMBOL_TAG_INCLUDE__DEFAULT_ONLY && 431 (versioning = strstr(name, "@@"))) { 432 int len = strlen(str); 433 434 if (len < versioning - name) 435 len = versioning - name; 436 437 return arch__compare_symbol_names_n(name, str, len); 438 } else 439 return arch__compare_symbol_names(name, str); 440 } 441 442 static struct symbol *symbols__find_by_name(struct rb_root_cached *symbols, 443 const char *name, 444 enum symbol_tag_include includes) 445 { 446 struct rb_node *n; 447 struct symbol_name_rb_node *s = NULL; 448 449 if (symbols == NULL) 450 return NULL; 451 452 n = symbols->rb_root.rb_node; 453 454 while (n) { 455 int cmp; 456 457 s = rb_entry(n, struct symbol_name_rb_node, rb_node); 458 cmp = symbol__match_symbol_name(s->sym.name, name, includes); 459 460 if (cmp > 0) 461 n = n->rb_left; 462 else if (cmp < 0) 463 n = n->rb_right; 464 else 465 break; 466 } 467 468 if (n == NULL) 469 return NULL; 470 471 if (includes != SYMBOL_TAG_INCLUDE__DEFAULT_ONLY) 472 /* return first symbol that has same name (if any) */ 473 for (n = rb_prev(n); n; n = rb_prev(n)) { 474 struct symbol_name_rb_node *tmp; 475 476 tmp = rb_entry(n, struct symbol_name_rb_node, rb_node); 477 if (arch__compare_symbol_names(tmp->sym.name, s->sym.name)) 478 break; 479 480 s = tmp; 481 } 482 483 return &s->sym; 484 } 485 486 void dso__reset_find_symbol_cache(struct dso *dso) 487 { 488 dso->last_find_result.addr = 0; 489 dso->last_find_result.symbol = NULL; 490 } 491 492 void dso__insert_symbol(struct dso *dso, struct symbol *sym) 493 { 494 __symbols__insert(&dso->symbols, sym, dso->kernel); 495 496 /* update the symbol cache if necessary */ 497 if (dso->last_find_result.addr >= sym->start && 498 (dso->last_find_result.addr < sym->end || 499 sym->start == sym->end)) { 500 dso->last_find_result.symbol = sym; 501 } 502 } 503 504 struct symbol *dso__find_symbol(struct dso *dso, u64 addr) 505 { 506 if (dso->last_find_result.addr != addr || dso->last_find_result.symbol == NULL) { 507 dso->last_find_result.addr = addr; 508 dso->last_find_result.symbol = symbols__find(&dso->symbols, addr); 509 } 510 511 return dso->last_find_result.symbol; 512 } 513 514 struct symbol *dso__first_symbol(struct dso *dso) 515 { 516 return symbols__first(&dso->symbols); 517 } 518 519 struct symbol *dso__last_symbol(struct dso *dso) 520 { 521 return symbols__last(&dso->symbols); 522 } 523 524 struct symbol *dso__next_symbol(struct symbol *sym) 525 { 526 return symbols__next(sym); 527 } 528 529 struct symbol *symbol__next_by_name(struct symbol *sym) 530 { 531 struct symbol_name_rb_node *s = container_of(sym, struct symbol_name_rb_node, sym); 532 struct rb_node *n = rb_next(&s->rb_node); 533 534 return n ? &rb_entry(n, struct symbol_name_rb_node, rb_node)->sym : NULL; 535 } 536 537 /* 538 * Returns first symbol that matched with @name. 539 */ 540 struct symbol *dso__find_symbol_by_name(struct dso *dso, const char *name) 541 { 542 struct symbol *s = symbols__find_by_name(&dso->symbol_names, name, 543 SYMBOL_TAG_INCLUDE__NONE); 544 if (!s) 545 s = symbols__find_by_name(&dso->symbol_names, name, 546 SYMBOL_TAG_INCLUDE__DEFAULT_ONLY); 547 return s; 548 } 549 550 void dso__sort_by_name(struct dso *dso) 551 { 552 dso__set_sorted_by_name(dso); 553 return symbols__sort_by_name(&dso->symbol_names, &dso->symbols); 554 } 555 556 int modules__parse(const char *filename, void *arg, 557 int (*process_module)(void *arg, const char *name, 558 u64 start, u64 size)) 559 { 560 char *line = NULL; 561 size_t n; 562 FILE *file; 563 int err = 0; 564 565 file = fopen(filename, "r"); 566 if (file == NULL) 567 return -1; 568 569 while (1) { 570 char name[PATH_MAX]; 571 u64 start, size; 572 char *sep, *endptr; 573 ssize_t line_len; 574 575 line_len = getline(&line, &n, file); 576 if (line_len < 0) { 577 if (feof(file)) 578 break; 579 err = -1; 580 goto out; 581 } 582 583 if (!line) { 584 err = -1; 585 goto out; 586 } 587 588 line[--line_len] = '\0'; /* \n */ 589 590 sep = strrchr(line, 'x'); 591 if (sep == NULL) 592 continue; 593 594 hex2u64(sep + 1, &start); 595 596 sep = strchr(line, ' '); 597 if (sep == NULL) 598 continue; 599 600 *sep = '\0'; 601 602 scnprintf(name, sizeof(name), "[%s]", line); 603 604 size = strtoul(sep + 1, &endptr, 0); 605 if (*endptr != ' ' && *endptr != '\t') 606 continue; 607 608 err = process_module(arg, name, start, size); 609 if (err) 610 break; 611 } 612 out: 613 free(line); 614 fclose(file); 615 return err; 616 } 617 618 /* 619 * These are symbols in the kernel image, so make sure that 620 * sym is from a kernel DSO. 621 */ 622 static bool symbol__is_idle(const char *name) 623 { 624 const char * const idle_symbols[] = { 625 "arch_cpu_idle", 626 "cpu_idle", 627 "cpu_startup_entry", 628 "intel_idle", 629 "default_idle", 630 "native_safe_halt", 631 "enter_idle", 632 "exit_idle", 633 "mwait_idle", 634 "mwait_idle_with_hints", 635 "poll_idle", 636 "ppc64_runlatch_off", 637 "pseries_dedicated_idle_sleep", 638 NULL 639 }; 640 int i; 641 642 for (i = 0; idle_symbols[i]; i++) { 643 if (!strcmp(idle_symbols[i], name)) 644 return true; 645 } 646 647 return false; 648 } 649 650 static int map__process_kallsym_symbol(void *arg, const char *name, 651 char type, u64 start) 652 { 653 struct symbol *sym; 654 struct dso *dso = arg; 655 struct rb_root_cached *root = &dso->symbols; 656 657 if (!symbol_type__filter(type)) 658 return 0; 659 660 /* 661 * module symbols are not sorted so we add all 662 * symbols, setting length to 0, and rely on 663 * symbols__fixup_end() to fix it up. 664 */ 665 sym = symbol__new(start, 0, kallsyms2elf_binding(type), kallsyms2elf_type(type), name); 666 if (sym == NULL) 667 return -ENOMEM; 668 /* 669 * We will pass the symbols to the filter later, in 670 * map__split_kallsyms, when we have split the maps per module 671 */ 672 __symbols__insert(root, sym, !strchr(name, '[')); 673 674 return 0; 675 } 676 677 /* 678 * Loads the function entries in /proc/kallsyms into kernel_map->dso, 679 * so that we can in the next step set the symbol ->end address and then 680 * call kernel_maps__split_kallsyms. 681 */ 682 static int dso__load_all_kallsyms(struct dso *dso, const char *filename) 683 { 684 return kallsyms__parse(filename, dso, map__process_kallsym_symbol); 685 } 686 687 static int map_groups__split_kallsyms_for_kcore(struct map_groups *kmaps, struct dso *dso) 688 { 689 struct map *curr_map; 690 struct symbol *pos; 691 int count = 0; 692 struct rb_root_cached old_root = dso->symbols; 693 struct rb_root_cached *root = &dso->symbols; 694 struct rb_node *next = rb_first_cached(root); 695 696 if (!kmaps) 697 return -1; 698 699 *root = RB_ROOT_CACHED; 700 701 while (next) { 702 char *module; 703 704 pos = rb_entry(next, struct symbol, rb_node); 705 next = rb_next(&pos->rb_node); 706 707 rb_erase_cached(&pos->rb_node, &old_root); 708 RB_CLEAR_NODE(&pos->rb_node); 709 module = strchr(pos->name, '\t'); 710 if (module) 711 *module = '\0'; 712 713 curr_map = map_groups__find(kmaps, pos->start); 714 715 if (!curr_map) { 716 symbol__delete(pos); 717 continue; 718 } 719 720 pos->start -= curr_map->start - curr_map->pgoff; 721 if (pos->end > curr_map->end) 722 pos->end = curr_map->end; 723 if (pos->end) 724 pos->end -= curr_map->start - curr_map->pgoff; 725 symbols__insert(&curr_map->dso->symbols, pos); 726 ++count; 727 } 728 729 /* Symbols have been adjusted */ 730 dso->adjust_symbols = 1; 731 732 return count; 733 } 734 735 /* 736 * Split the symbols into maps, making sure there are no overlaps, i.e. the 737 * kernel range is broken in several maps, named [kernel].N, as we don't have 738 * the original ELF section names vmlinux have. 739 */ 740 static int map_groups__split_kallsyms(struct map_groups *kmaps, struct dso *dso, u64 delta, 741 struct map *initial_map) 742 { 743 struct machine *machine; 744 struct map *curr_map = initial_map; 745 struct symbol *pos; 746 int count = 0, moved = 0; 747 struct rb_root_cached *root = &dso->symbols; 748 struct rb_node *next = rb_first_cached(root); 749 int kernel_range = 0; 750 bool x86_64; 751 752 if (!kmaps) 753 return -1; 754 755 machine = kmaps->machine; 756 757 x86_64 = machine__is(machine, "x86_64"); 758 759 while (next) { 760 char *module; 761 762 pos = rb_entry(next, struct symbol, rb_node); 763 next = rb_next(&pos->rb_node); 764 765 module = strchr(pos->name, '\t'); 766 if (module) { 767 if (!symbol_conf.use_modules) 768 goto discard_symbol; 769 770 *module++ = '\0'; 771 772 if (strcmp(curr_map->dso->short_name, module)) { 773 if (curr_map != initial_map && 774 dso->kernel == DSO_TYPE_GUEST_KERNEL && 775 machine__is_default_guest(machine)) { 776 /* 777 * We assume all symbols of a module are 778 * continuous in * kallsyms, so curr_map 779 * points to a module and all its 780 * symbols are in its kmap. Mark it as 781 * loaded. 782 */ 783 dso__set_loaded(curr_map->dso); 784 } 785 786 curr_map = map_groups__find_by_name(kmaps, module); 787 if (curr_map == NULL) { 788 pr_debug("%s/proc/{kallsyms,modules} " 789 "inconsistency while looking " 790 "for \"%s\" module!\n", 791 machine->root_dir, module); 792 curr_map = initial_map; 793 goto discard_symbol; 794 } 795 796 if (curr_map->dso->loaded && 797 !machine__is_default_guest(machine)) 798 goto discard_symbol; 799 } 800 /* 801 * So that we look just like we get from .ko files, 802 * i.e. not prelinked, relative to initial_map->start. 803 */ 804 pos->start = curr_map->map_ip(curr_map, pos->start); 805 pos->end = curr_map->map_ip(curr_map, pos->end); 806 } else if (x86_64 && is_entry_trampoline(pos->name)) { 807 /* 808 * These symbols are not needed anymore since the 809 * trampoline maps refer to the text section and it's 810 * symbols instead. Avoid having to deal with 811 * relocations, and the assumption that the first symbol 812 * is the start of kernel text, by simply removing the 813 * symbols at this point. 814 */ 815 goto discard_symbol; 816 } else if (curr_map != initial_map) { 817 char dso_name[PATH_MAX]; 818 struct dso *ndso; 819 820 if (delta) { 821 /* Kernel was relocated at boot time */ 822 pos->start -= delta; 823 pos->end -= delta; 824 } 825 826 if (count == 0) { 827 curr_map = initial_map; 828 goto add_symbol; 829 } 830 831 if (dso->kernel == DSO_TYPE_GUEST_KERNEL) 832 snprintf(dso_name, sizeof(dso_name), 833 "[guest.kernel].%d", 834 kernel_range++); 835 else 836 snprintf(dso_name, sizeof(dso_name), 837 "[kernel].%d", 838 kernel_range++); 839 840 ndso = dso__new(dso_name); 841 if (ndso == NULL) 842 return -1; 843 844 ndso->kernel = dso->kernel; 845 846 curr_map = map__new2(pos->start, ndso); 847 if (curr_map == NULL) { 848 dso__put(ndso); 849 return -1; 850 } 851 852 curr_map->map_ip = curr_map->unmap_ip = identity__map_ip; 853 map_groups__insert(kmaps, curr_map); 854 ++kernel_range; 855 } else if (delta) { 856 /* Kernel was relocated at boot time */ 857 pos->start -= delta; 858 pos->end -= delta; 859 } 860 add_symbol: 861 if (curr_map != initial_map) { 862 rb_erase_cached(&pos->rb_node, root); 863 symbols__insert(&curr_map->dso->symbols, pos); 864 ++moved; 865 } else 866 ++count; 867 868 continue; 869 discard_symbol: 870 rb_erase_cached(&pos->rb_node, root); 871 symbol__delete(pos); 872 } 873 874 if (curr_map != initial_map && 875 dso->kernel == DSO_TYPE_GUEST_KERNEL && 876 machine__is_default_guest(kmaps->machine)) { 877 dso__set_loaded(curr_map->dso); 878 } 879 880 return count + moved; 881 } 882 883 bool symbol__restricted_filename(const char *filename, 884 const char *restricted_filename) 885 { 886 bool restricted = false; 887 888 if (symbol_conf.kptr_restrict) { 889 char *r = realpath(filename, NULL); 890 891 if (r != NULL) { 892 restricted = strcmp(r, restricted_filename) == 0; 893 free(r); 894 return restricted; 895 } 896 } 897 898 return restricted; 899 } 900 901 struct module_info { 902 struct rb_node rb_node; 903 char *name; 904 u64 start; 905 }; 906 907 static void add_module(struct module_info *mi, struct rb_root *modules) 908 { 909 struct rb_node **p = &modules->rb_node; 910 struct rb_node *parent = NULL; 911 struct module_info *m; 912 913 while (*p != NULL) { 914 parent = *p; 915 m = rb_entry(parent, struct module_info, rb_node); 916 if (strcmp(mi->name, m->name) < 0) 917 p = &(*p)->rb_left; 918 else 919 p = &(*p)->rb_right; 920 } 921 rb_link_node(&mi->rb_node, parent, p); 922 rb_insert_color(&mi->rb_node, modules); 923 } 924 925 static void delete_modules(struct rb_root *modules) 926 { 927 struct module_info *mi; 928 struct rb_node *next = rb_first(modules); 929 930 while (next) { 931 mi = rb_entry(next, struct module_info, rb_node); 932 next = rb_next(&mi->rb_node); 933 rb_erase(&mi->rb_node, modules); 934 zfree(&mi->name); 935 free(mi); 936 } 937 } 938 939 static struct module_info *find_module(const char *name, 940 struct rb_root *modules) 941 { 942 struct rb_node *n = modules->rb_node; 943 944 while (n) { 945 struct module_info *m; 946 int cmp; 947 948 m = rb_entry(n, struct module_info, rb_node); 949 cmp = strcmp(name, m->name); 950 if (cmp < 0) 951 n = n->rb_left; 952 else if (cmp > 0) 953 n = n->rb_right; 954 else 955 return m; 956 } 957 958 return NULL; 959 } 960 961 static int __read_proc_modules(void *arg, const char *name, u64 start, 962 u64 size __maybe_unused) 963 { 964 struct rb_root *modules = arg; 965 struct module_info *mi; 966 967 mi = zalloc(sizeof(struct module_info)); 968 if (!mi) 969 return -ENOMEM; 970 971 mi->name = strdup(name); 972 mi->start = start; 973 974 if (!mi->name) { 975 free(mi); 976 return -ENOMEM; 977 } 978 979 add_module(mi, modules); 980 981 return 0; 982 } 983 984 static int read_proc_modules(const char *filename, struct rb_root *modules) 985 { 986 if (symbol__restricted_filename(filename, "/proc/modules")) 987 return -1; 988 989 if (modules__parse(filename, modules, __read_proc_modules)) { 990 delete_modules(modules); 991 return -1; 992 } 993 994 return 0; 995 } 996 997 int compare_proc_modules(const char *from, const char *to) 998 { 999 struct rb_root from_modules = RB_ROOT; 1000 struct rb_root to_modules = RB_ROOT; 1001 struct rb_node *from_node, *to_node; 1002 struct module_info *from_m, *to_m; 1003 int ret = -1; 1004 1005 if (read_proc_modules(from, &from_modules)) 1006 return -1; 1007 1008 if (read_proc_modules(to, &to_modules)) 1009 goto out_delete_from; 1010 1011 from_node = rb_first(&from_modules); 1012 to_node = rb_first(&to_modules); 1013 while (from_node) { 1014 if (!to_node) 1015 break; 1016 1017 from_m = rb_entry(from_node, struct module_info, rb_node); 1018 to_m = rb_entry(to_node, struct module_info, rb_node); 1019 1020 if (from_m->start != to_m->start || 1021 strcmp(from_m->name, to_m->name)) 1022 break; 1023 1024 from_node = rb_next(from_node); 1025 to_node = rb_next(to_node); 1026 } 1027 1028 if (!from_node && !to_node) 1029 ret = 0; 1030 1031 delete_modules(&to_modules); 1032 out_delete_from: 1033 delete_modules(&from_modules); 1034 1035 return ret; 1036 } 1037 1038 struct map *map_groups__first(struct map_groups *mg) 1039 { 1040 return maps__first(&mg->maps); 1041 } 1042 1043 static int do_validate_kcore_modules(const char *filename, 1044 struct map_groups *kmaps) 1045 { 1046 struct rb_root modules = RB_ROOT; 1047 struct map *old_map; 1048 int err; 1049 1050 err = read_proc_modules(filename, &modules); 1051 if (err) 1052 return err; 1053 1054 old_map = map_groups__first(kmaps); 1055 while (old_map) { 1056 struct map *next = map_groups__next(old_map); 1057 struct module_info *mi; 1058 1059 if (!__map__is_kmodule(old_map)) { 1060 old_map = next; 1061 continue; 1062 } 1063 1064 /* Module must be in memory at the same address */ 1065 mi = find_module(old_map->dso->short_name, &modules); 1066 if (!mi || mi->start != old_map->start) { 1067 err = -EINVAL; 1068 goto out; 1069 } 1070 1071 old_map = next; 1072 } 1073 out: 1074 delete_modules(&modules); 1075 return err; 1076 } 1077 1078 /* 1079 * If kallsyms is referenced by name then we look for filename in the same 1080 * directory. 1081 */ 1082 static bool filename_from_kallsyms_filename(char *filename, 1083 const char *base_name, 1084 const char *kallsyms_filename) 1085 { 1086 char *name; 1087 1088 strcpy(filename, kallsyms_filename); 1089 name = strrchr(filename, '/'); 1090 if (!name) 1091 return false; 1092 1093 name += 1; 1094 1095 if (!strcmp(name, "kallsyms")) { 1096 strcpy(name, base_name); 1097 return true; 1098 } 1099 1100 return false; 1101 } 1102 1103 static int validate_kcore_modules(const char *kallsyms_filename, 1104 struct map *map) 1105 { 1106 struct map_groups *kmaps = map__kmaps(map); 1107 char modules_filename[PATH_MAX]; 1108 1109 if (!kmaps) 1110 return -EINVAL; 1111 1112 if (!filename_from_kallsyms_filename(modules_filename, "modules", 1113 kallsyms_filename)) 1114 return -EINVAL; 1115 1116 if (do_validate_kcore_modules(modules_filename, kmaps)) 1117 return -EINVAL; 1118 1119 return 0; 1120 } 1121 1122 static int validate_kcore_addresses(const char *kallsyms_filename, 1123 struct map *map) 1124 { 1125 struct kmap *kmap = map__kmap(map); 1126 1127 if (!kmap) 1128 return -EINVAL; 1129 1130 if (kmap->ref_reloc_sym && kmap->ref_reloc_sym->name) { 1131 u64 start; 1132 1133 if (kallsyms__get_function_start(kallsyms_filename, 1134 kmap->ref_reloc_sym->name, &start)) 1135 return -ENOENT; 1136 if (start != kmap->ref_reloc_sym->addr) 1137 return -EINVAL; 1138 } 1139 1140 return validate_kcore_modules(kallsyms_filename, map); 1141 } 1142 1143 struct kcore_mapfn_data { 1144 struct dso *dso; 1145 struct list_head maps; 1146 }; 1147 1148 static int kcore_mapfn(u64 start, u64 len, u64 pgoff, void *data) 1149 { 1150 struct kcore_mapfn_data *md = data; 1151 struct map *map; 1152 1153 map = map__new2(start, md->dso); 1154 if (map == NULL) 1155 return -ENOMEM; 1156 1157 map->end = map->start + len; 1158 map->pgoff = pgoff; 1159 1160 list_add(&map->node, &md->maps); 1161 1162 return 0; 1163 } 1164 1165 static int dso__load_kcore(struct dso *dso, struct map *map, 1166 const char *kallsyms_filename) 1167 { 1168 struct map_groups *kmaps = map__kmaps(map); 1169 struct kcore_mapfn_data md; 1170 struct map *old_map, *new_map, *replacement_map = NULL; 1171 struct machine *machine; 1172 bool is_64_bit; 1173 int err, fd; 1174 char kcore_filename[PATH_MAX]; 1175 u64 stext; 1176 1177 if (!kmaps) 1178 return -EINVAL; 1179 1180 machine = kmaps->machine; 1181 1182 /* This function requires that the map is the kernel map */ 1183 if (!__map__is_kernel(map)) 1184 return -EINVAL; 1185 1186 if (!filename_from_kallsyms_filename(kcore_filename, "kcore", 1187 kallsyms_filename)) 1188 return -EINVAL; 1189 1190 /* Modules and kernel must be present at their original addresses */ 1191 if (validate_kcore_addresses(kallsyms_filename, map)) 1192 return -EINVAL; 1193 1194 md.dso = dso; 1195 INIT_LIST_HEAD(&md.maps); 1196 1197 fd = open(kcore_filename, O_RDONLY); 1198 if (fd < 0) { 1199 pr_debug("Failed to open %s. Note /proc/kcore requires CAP_SYS_RAWIO capability to access.\n", 1200 kcore_filename); 1201 return -EINVAL; 1202 } 1203 1204 /* Read new maps into temporary lists */ 1205 err = file__read_maps(fd, map->prot & PROT_EXEC, kcore_mapfn, &md, 1206 &is_64_bit); 1207 if (err) 1208 goto out_err; 1209 dso->is_64_bit = is_64_bit; 1210 1211 if (list_empty(&md.maps)) { 1212 err = -EINVAL; 1213 goto out_err; 1214 } 1215 1216 /* Remove old maps */ 1217 old_map = map_groups__first(kmaps); 1218 while (old_map) { 1219 struct map *next = map_groups__next(old_map); 1220 1221 if (old_map != map) 1222 map_groups__remove(kmaps, old_map); 1223 old_map = next; 1224 } 1225 machine->trampolines_mapped = false; 1226 1227 /* Find the kernel map using the '_stext' symbol */ 1228 if (!kallsyms__get_function_start(kallsyms_filename, "_stext", &stext)) { 1229 list_for_each_entry(new_map, &md.maps, node) { 1230 if (stext >= new_map->start && stext < new_map->end) { 1231 replacement_map = new_map; 1232 break; 1233 } 1234 } 1235 } 1236 1237 if (!replacement_map) 1238 replacement_map = list_entry(md.maps.next, struct map, node); 1239 1240 /* Add new maps */ 1241 while (!list_empty(&md.maps)) { 1242 new_map = list_entry(md.maps.next, struct map, node); 1243 list_del_init(&new_map->node); 1244 if (new_map == replacement_map) { 1245 map->start = new_map->start; 1246 map->end = new_map->end; 1247 map->pgoff = new_map->pgoff; 1248 map->map_ip = new_map->map_ip; 1249 map->unmap_ip = new_map->unmap_ip; 1250 /* Ensure maps are correctly ordered */ 1251 map__get(map); 1252 map_groups__remove(kmaps, map); 1253 map_groups__insert(kmaps, map); 1254 map__put(map); 1255 } else { 1256 map_groups__insert(kmaps, new_map); 1257 } 1258 1259 map__put(new_map); 1260 } 1261 1262 if (machine__is(machine, "x86_64")) { 1263 u64 addr; 1264 1265 /* 1266 * If one of the corresponding symbols is there, assume the 1267 * entry trampoline maps are too. 1268 */ 1269 if (!kallsyms__get_function_start(kallsyms_filename, 1270 ENTRY_TRAMPOLINE_NAME, 1271 &addr)) 1272 machine->trampolines_mapped = true; 1273 } 1274 1275 /* 1276 * Set the data type and long name so that kcore can be read via 1277 * dso__data_read_addr(). 1278 */ 1279 if (dso->kernel == DSO_TYPE_GUEST_KERNEL) 1280 dso->binary_type = DSO_BINARY_TYPE__GUEST_KCORE; 1281 else 1282 dso->binary_type = DSO_BINARY_TYPE__KCORE; 1283 dso__set_long_name(dso, strdup(kcore_filename), true); 1284 1285 close(fd); 1286 1287 if (map->prot & PROT_EXEC) 1288 pr_debug("Using %s for kernel object code\n", kcore_filename); 1289 else 1290 pr_debug("Using %s for kernel data\n", kcore_filename); 1291 1292 return 0; 1293 1294 out_err: 1295 while (!list_empty(&md.maps)) { 1296 map = list_entry(md.maps.next, struct map, node); 1297 list_del_init(&map->node); 1298 map__put(map); 1299 } 1300 close(fd); 1301 return -EINVAL; 1302 } 1303 1304 /* 1305 * If the kernel is relocated at boot time, kallsyms won't match. Compute the 1306 * delta based on the relocation reference symbol. 1307 */ 1308 static int kallsyms__delta(struct kmap *kmap, const char *filename, u64 *delta) 1309 { 1310 u64 addr; 1311 1312 if (!kmap->ref_reloc_sym || !kmap->ref_reloc_sym->name) 1313 return 0; 1314 1315 if (kallsyms__get_function_start(filename, kmap->ref_reloc_sym->name, &addr)) 1316 return -1; 1317 1318 *delta = addr - kmap->ref_reloc_sym->addr; 1319 return 0; 1320 } 1321 1322 int __dso__load_kallsyms(struct dso *dso, const char *filename, 1323 struct map *map, bool no_kcore) 1324 { 1325 struct kmap *kmap = map__kmap(map); 1326 u64 delta = 0; 1327 1328 if (symbol__restricted_filename(filename, "/proc/kallsyms")) 1329 return -1; 1330 1331 if (!kmap || !kmap->kmaps) 1332 return -1; 1333 1334 if (dso__load_all_kallsyms(dso, filename) < 0) 1335 return -1; 1336 1337 if (kallsyms__delta(kmap, filename, &delta)) 1338 return -1; 1339 1340 symbols__fixup_end(&dso->symbols); 1341 symbols__fixup_duplicate(&dso->symbols); 1342 1343 if (dso->kernel == DSO_TYPE_GUEST_KERNEL) 1344 dso->symtab_type = DSO_BINARY_TYPE__GUEST_KALLSYMS; 1345 else 1346 dso->symtab_type = DSO_BINARY_TYPE__KALLSYMS; 1347 1348 if (!no_kcore && !dso__load_kcore(dso, map, filename)) 1349 return map_groups__split_kallsyms_for_kcore(kmap->kmaps, dso); 1350 else 1351 return map_groups__split_kallsyms(kmap->kmaps, dso, delta, map); 1352 } 1353 1354 int dso__load_kallsyms(struct dso *dso, const char *filename, 1355 struct map *map) 1356 { 1357 return __dso__load_kallsyms(dso, filename, map, false); 1358 } 1359 1360 static int dso__load_perf_map(const char *map_path, struct dso *dso) 1361 { 1362 char *line = NULL; 1363 size_t n; 1364 FILE *file; 1365 int nr_syms = 0; 1366 1367 file = fopen(map_path, "r"); 1368 if (file == NULL) 1369 goto out_failure; 1370 1371 while (!feof(file)) { 1372 u64 start, size; 1373 struct symbol *sym; 1374 int line_len, len; 1375 1376 line_len = getline(&line, &n, file); 1377 if (line_len < 0) 1378 break; 1379 1380 if (!line) 1381 goto out_failure; 1382 1383 line[--line_len] = '\0'; /* \n */ 1384 1385 len = hex2u64(line, &start); 1386 1387 len++; 1388 if (len + 2 >= line_len) 1389 continue; 1390 1391 len += hex2u64(line + len, &size); 1392 1393 len++; 1394 if (len + 2 >= line_len) 1395 continue; 1396 1397 sym = symbol__new(start, size, STB_GLOBAL, STT_FUNC, line + len); 1398 1399 if (sym == NULL) 1400 goto out_delete_line; 1401 1402 symbols__insert(&dso->symbols, sym); 1403 nr_syms++; 1404 } 1405 1406 free(line); 1407 fclose(file); 1408 1409 return nr_syms; 1410 1411 out_delete_line: 1412 free(line); 1413 out_failure: 1414 return -1; 1415 } 1416 1417 static bool dso__is_compatible_symtab_type(struct dso *dso, bool kmod, 1418 enum dso_binary_type type) 1419 { 1420 switch (type) { 1421 case DSO_BINARY_TYPE__JAVA_JIT: 1422 case DSO_BINARY_TYPE__DEBUGLINK: 1423 case DSO_BINARY_TYPE__SYSTEM_PATH_DSO: 1424 case DSO_BINARY_TYPE__FEDORA_DEBUGINFO: 1425 case DSO_BINARY_TYPE__UBUNTU_DEBUGINFO: 1426 case DSO_BINARY_TYPE__BUILDID_DEBUGINFO: 1427 case DSO_BINARY_TYPE__OPENEMBEDDED_DEBUGINFO: 1428 return !kmod && dso->kernel == DSO_TYPE_USER; 1429 1430 case DSO_BINARY_TYPE__KALLSYMS: 1431 case DSO_BINARY_TYPE__VMLINUX: 1432 case DSO_BINARY_TYPE__KCORE: 1433 return dso->kernel == DSO_TYPE_KERNEL; 1434 1435 case DSO_BINARY_TYPE__GUEST_KALLSYMS: 1436 case DSO_BINARY_TYPE__GUEST_VMLINUX: 1437 case DSO_BINARY_TYPE__GUEST_KCORE: 1438 return dso->kernel == DSO_TYPE_GUEST_KERNEL; 1439 1440 case DSO_BINARY_TYPE__GUEST_KMODULE: 1441 case DSO_BINARY_TYPE__GUEST_KMODULE_COMP: 1442 case DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE: 1443 case DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP: 1444 /* 1445 * kernel modules know their symtab type - it's set when 1446 * creating a module dso in machine__findnew_module_map(). 1447 */ 1448 return kmod && dso->symtab_type == type; 1449 1450 case DSO_BINARY_TYPE__BUILD_ID_CACHE: 1451 case DSO_BINARY_TYPE__BUILD_ID_CACHE_DEBUGINFO: 1452 return true; 1453 1454 case DSO_BINARY_TYPE__NOT_FOUND: 1455 default: 1456 return false; 1457 } 1458 } 1459 1460 /* Checks for the existence of the perf-<pid>.map file in two different 1461 * locations. First, if the process is a separate mount namespace, check in 1462 * that namespace using the pid of the innermost pid namespace. If's not in a 1463 * namespace, or the file can't be found there, try in the mount namespace of 1464 * the tracing process using our view of its pid. 1465 */ 1466 static int dso__find_perf_map(char *filebuf, size_t bufsz, 1467 struct nsinfo **nsip) 1468 { 1469 struct nscookie nsc; 1470 struct nsinfo *nsi; 1471 struct nsinfo *nnsi; 1472 int rc = -1; 1473 1474 nsi = *nsip; 1475 1476 if (nsi->need_setns) { 1477 snprintf(filebuf, bufsz, "/tmp/perf-%d.map", nsi->nstgid); 1478 nsinfo__mountns_enter(nsi, &nsc); 1479 rc = access(filebuf, R_OK); 1480 nsinfo__mountns_exit(&nsc); 1481 if (rc == 0) 1482 return rc; 1483 } 1484 1485 nnsi = nsinfo__copy(nsi); 1486 if (nnsi) { 1487 nsinfo__put(nsi); 1488 1489 nnsi->need_setns = false; 1490 snprintf(filebuf, bufsz, "/tmp/perf-%d.map", nnsi->tgid); 1491 *nsip = nnsi; 1492 rc = 0; 1493 } 1494 1495 return rc; 1496 } 1497 1498 int dso__load(struct dso *dso, struct map *map) 1499 { 1500 char *name; 1501 int ret = -1; 1502 u_int i; 1503 struct machine *machine; 1504 char *root_dir = (char *) ""; 1505 int ss_pos = 0; 1506 struct symsrc ss_[2]; 1507 struct symsrc *syms_ss = NULL, *runtime_ss = NULL; 1508 bool kmod; 1509 bool perfmap; 1510 unsigned char build_id[BUILD_ID_SIZE]; 1511 struct nscookie nsc; 1512 char newmapname[PATH_MAX]; 1513 const char *map_path = dso->long_name; 1514 1515 perfmap = strncmp(dso->name, "/tmp/perf-", 10) == 0; 1516 if (perfmap) { 1517 if (dso->nsinfo && (dso__find_perf_map(newmapname, 1518 sizeof(newmapname), &dso->nsinfo) == 0)) { 1519 map_path = newmapname; 1520 } 1521 } 1522 1523 nsinfo__mountns_enter(dso->nsinfo, &nsc); 1524 pthread_mutex_lock(&dso->lock); 1525 1526 /* check again under the dso->lock */ 1527 if (dso__loaded(dso)) { 1528 ret = 1; 1529 goto out; 1530 } 1531 1532 if (map->groups && map->groups->machine) 1533 machine = map->groups->machine; 1534 else 1535 machine = NULL; 1536 1537 if (dso->kernel) { 1538 if (dso->kernel == DSO_TYPE_KERNEL) 1539 ret = dso__load_kernel_sym(dso, map); 1540 else if (dso->kernel == DSO_TYPE_GUEST_KERNEL) 1541 ret = dso__load_guest_kernel_sym(dso, map); 1542 1543 if (machine__is(machine, "x86_64")) 1544 machine__map_x86_64_entry_trampolines(machine, dso); 1545 goto out; 1546 } 1547 1548 dso->adjust_symbols = 0; 1549 1550 if (perfmap) { 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 struct rb_node *node; 1684 1685 down_read(&maps->lock); 1686 1687 for (node = maps->names.rb_node; node; ) { 1688 int rc; 1689 1690 map = rb_entry(node, struct map, rb_node_name); 1691 1692 rc = strcmp(map->dso->short_name, name); 1693 if (rc < 0) 1694 node = node->rb_left; 1695 else if (rc > 0) 1696 node = node->rb_right; 1697 else 1698 1699 goto out_unlock; 1700 } 1701 1702 map = NULL; 1703 1704 out_unlock: 1705 up_read(&maps->lock); 1706 return map; 1707 } 1708 1709 int dso__load_vmlinux(struct dso *dso, struct map *map, 1710 const char *vmlinux, bool vmlinux_allocated) 1711 { 1712 int err = -1; 1713 struct symsrc ss; 1714 char symfs_vmlinux[PATH_MAX]; 1715 enum dso_binary_type symtab_type; 1716 1717 if (vmlinux[0] == '/') 1718 snprintf(symfs_vmlinux, sizeof(symfs_vmlinux), "%s", vmlinux); 1719 else 1720 symbol__join_symfs(symfs_vmlinux, vmlinux); 1721 1722 if (dso->kernel == DSO_TYPE_GUEST_KERNEL) 1723 symtab_type = DSO_BINARY_TYPE__GUEST_VMLINUX; 1724 else 1725 symtab_type = DSO_BINARY_TYPE__VMLINUX; 1726 1727 if (symsrc__init(&ss, dso, symfs_vmlinux, symtab_type)) 1728 return -1; 1729 1730 err = dso__load_sym(dso, map, &ss, &ss, 0); 1731 symsrc__destroy(&ss); 1732 1733 if (err > 0) { 1734 if (dso->kernel == DSO_TYPE_GUEST_KERNEL) 1735 dso->binary_type = DSO_BINARY_TYPE__GUEST_VMLINUX; 1736 else 1737 dso->binary_type = DSO_BINARY_TYPE__VMLINUX; 1738 dso__set_long_name(dso, vmlinux, vmlinux_allocated); 1739 dso__set_loaded(dso); 1740 pr_debug("Using %s for symbols\n", symfs_vmlinux); 1741 } 1742 1743 return err; 1744 } 1745 1746 int dso__load_vmlinux_path(struct dso *dso, struct map *map) 1747 { 1748 int i, err = 0; 1749 char *filename = NULL; 1750 1751 pr_debug("Looking at the vmlinux_path (%d entries long)\n", 1752 vmlinux_path__nr_entries + 1); 1753 1754 for (i = 0; i < vmlinux_path__nr_entries; ++i) { 1755 err = dso__load_vmlinux(dso, map, vmlinux_path[i], false); 1756 if (err > 0) 1757 goto out; 1758 } 1759 1760 if (!symbol_conf.ignore_vmlinux_buildid) 1761 filename = dso__build_id_filename(dso, NULL, 0, false); 1762 if (filename != NULL) { 1763 err = dso__load_vmlinux(dso, map, filename, true); 1764 if (err > 0) 1765 goto out; 1766 free(filename); 1767 } 1768 out: 1769 return err; 1770 } 1771 1772 static bool visible_dir_filter(const char *name, struct dirent *d) 1773 { 1774 if (d->d_type != DT_DIR) 1775 return false; 1776 return lsdir_no_dot_filter(name, d); 1777 } 1778 1779 static int find_matching_kcore(struct map *map, char *dir, size_t dir_sz) 1780 { 1781 char kallsyms_filename[PATH_MAX]; 1782 int ret = -1; 1783 struct strlist *dirs; 1784 struct str_node *nd; 1785 1786 dirs = lsdir(dir, visible_dir_filter); 1787 if (!dirs) 1788 return -1; 1789 1790 strlist__for_each_entry(nd, dirs) { 1791 scnprintf(kallsyms_filename, sizeof(kallsyms_filename), 1792 "%s/%s/kallsyms", dir, nd->s); 1793 if (!validate_kcore_addresses(kallsyms_filename, map)) { 1794 strlcpy(dir, kallsyms_filename, dir_sz); 1795 ret = 0; 1796 break; 1797 } 1798 } 1799 1800 strlist__delete(dirs); 1801 1802 return ret; 1803 } 1804 1805 /* 1806 * Use open(O_RDONLY) to check readability directly instead of access(R_OK) 1807 * since access(R_OK) only checks with real UID/GID but open() use effective 1808 * UID/GID and actual capabilities (e.g. /proc/kcore requires CAP_SYS_RAWIO). 1809 */ 1810 static bool filename__readable(const char *file) 1811 { 1812 int fd = open(file, O_RDONLY); 1813 if (fd < 0) 1814 return false; 1815 close(fd); 1816 return true; 1817 } 1818 1819 static char *dso__find_kallsyms(struct dso *dso, struct map *map) 1820 { 1821 u8 host_build_id[BUILD_ID_SIZE]; 1822 char sbuild_id[SBUILD_ID_SIZE]; 1823 bool is_host = false; 1824 char path[PATH_MAX]; 1825 1826 if (!dso->has_build_id) { 1827 /* 1828 * Last resort, if we don't have a build-id and couldn't find 1829 * any vmlinux file, try the running kernel kallsyms table. 1830 */ 1831 goto proc_kallsyms; 1832 } 1833 1834 if (sysfs__read_build_id("/sys/kernel/notes", host_build_id, 1835 sizeof(host_build_id)) == 0) 1836 is_host = dso__build_id_equal(dso, host_build_id); 1837 1838 /* Try a fast path for /proc/kallsyms if possible */ 1839 if (is_host) { 1840 /* 1841 * Do not check the build-id cache, unless we know we cannot use 1842 * /proc/kcore or module maps don't match to /proc/kallsyms. 1843 * To check readability of /proc/kcore, do not use access(R_OK) 1844 * since /proc/kcore requires CAP_SYS_RAWIO to read and access 1845 * can't check it. 1846 */ 1847 if (filename__readable("/proc/kcore") && 1848 !validate_kcore_addresses("/proc/kallsyms", map)) 1849 goto proc_kallsyms; 1850 } 1851 1852 build_id__sprintf(dso->build_id, sizeof(dso->build_id), sbuild_id); 1853 1854 /* Find kallsyms in build-id cache with kcore */ 1855 scnprintf(path, sizeof(path), "%s/%s/%s", 1856 buildid_dir, DSO__NAME_KCORE, sbuild_id); 1857 1858 if (!find_matching_kcore(map, path, sizeof(path))) 1859 return strdup(path); 1860 1861 /* Use current /proc/kallsyms if possible */ 1862 if (is_host) { 1863 proc_kallsyms: 1864 return strdup("/proc/kallsyms"); 1865 } 1866 1867 /* Finally, find a cache of kallsyms */ 1868 if (!build_id_cache__kallsyms_path(sbuild_id, path, sizeof(path))) { 1869 pr_err("No kallsyms or vmlinux with build-id %s was found\n", 1870 sbuild_id); 1871 return NULL; 1872 } 1873 1874 return strdup(path); 1875 } 1876 1877 static int dso__load_kernel_sym(struct dso *dso, struct map *map) 1878 { 1879 int err; 1880 const char *kallsyms_filename = NULL; 1881 char *kallsyms_allocated_filename = NULL; 1882 /* 1883 * Step 1: if the user specified a kallsyms or vmlinux filename, use 1884 * it and only it, reporting errors to the user if it cannot be used. 1885 * 1886 * For instance, try to analyse an ARM perf.data file _without_ a 1887 * build-id, or if the user specifies the wrong path to the right 1888 * vmlinux file, obviously we can't fallback to another vmlinux (a 1889 * x86_86 one, on the machine where analysis is being performed, say), 1890 * or worse, /proc/kallsyms. 1891 * 1892 * If the specified file _has_ a build-id and there is a build-id 1893 * section in the perf.data file, we will still do the expected 1894 * validation in dso__load_vmlinux and will bail out if they don't 1895 * match. 1896 */ 1897 if (symbol_conf.kallsyms_name != NULL) { 1898 kallsyms_filename = symbol_conf.kallsyms_name; 1899 goto do_kallsyms; 1900 } 1901 1902 if (!symbol_conf.ignore_vmlinux && symbol_conf.vmlinux_name != NULL) { 1903 return dso__load_vmlinux(dso, map, symbol_conf.vmlinux_name, false); 1904 } 1905 1906 if (!symbol_conf.ignore_vmlinux && vmlinux_path != NULL) { 1907 err = dso__load_vmlinux_path(dso, map); 1908 if (err > 0) 1909 return err; 1910 } 1911 1912 /* do not try local files if a symfs was given */ 1913 if (symbol_conf.symfs[0] != 0) 1914 return -1; 1915 1916 kallsyms_allocated_filename = dso__find_kallsyms(dso, map); 1917 if (!kallsyms_allocated_filename) 1918 return -1; 1919 1920 kallsyms_filename = kallsyms_allocated_filename; 1921 1922 do_kallsyms: 1923 err = dso__load_kallsyms(dso, kallsyms_filename, map); 1924 if (err > 0) 1925 pr_debug("Using %s for symbols\n", kallsyms_filename); 1926 free(kallsyms_allocated_filename); 1927 1928 if (err > 0 && !dso__is_kcore(dso)) { 1929 dso->binary_type = DSO_BINARY_TYPE__KALLSYMS; 1930 dso__set_long_name(dso, DSO__NAME_KALLSYMS, false); 1931 map__fixup_start(map); 1932 map__fixup_end(map); 1933 } 1934 1935 return err; 1936 } 1937 1938 static int dso__load_guest_kernel_sym(struct dso *dso, struct map *map) 1939 { 1940 int err; 1941 const char *kallsyms_filename = NULL; 1942 struct machine *machine; 1943 char path[PATH_MAX]; 1944 1945 if (!map->groups) { 1946 pr_debug("Guest kernel map hasn't the point to groups\n"); 1947 return -1; 1948 } 1949 machine = map->groups->machine; 1950 1951 if (machine__is_default_guest(machine)) { 1952 /* 1953 * if the user specified a vmlinux filename, use it and only 1954 * it, reporting errors to the user if it cannot be used. 1955 * Or use file guest_kallsyms inputted by user on commandline 1956 */ 1957 if (symbol_conf.default_guest_vmlinux_name != NULL) { 1958 err = dso__load_vmlinux(dso, map, 1959 symbol_conf.default_guest_vmlinux_name, 1960 false); 1961 return err; 1962 } 1963 1964 kallsyms_filename = symbol_conf.default_guest_kallsyms; 1965 if (!kallsyms_filename) 1966 return -1; 1967 } else { 1968 sprintf(path, "%s/proc/kallsyms", machine->root_dir); 1969 kallsyms_filename = path; 1970 } 1971 1972 err = dso__load_kallsyms(dso, kallsyms_filename, map); 1973 if (err > 0) 1974 pr_debug("Using %s for symbols\n", kallsyms_filename); 1975 if (err > 0 && !dso__is_kcore(dso)) { 1976 dso->binary_type = DSO_BINARY_TYPE__GUEST_KALLSYMS; 1977 dso__set_long_name(dso, machine->mmap_name, false); 1978 map__fixup_start(map); 1979 map__fixup_end(map); 1980 } 1981 1982 return err; 1983 } 1984 1985 static void vmlinux_path__exit(void) 1986 { 1987 while (--vmlinux_path__nr_entries >= 0) 1988 zfree(&vmlinux_path[vmlinux_path__nr_entries]); 1989 vmlinux_path__nr_entries = 0; 1990 1991 zfree(&vmlinux_path); 1992 } 1993 1994 static const char * const vmlinux_paths[] = { 1995 "vmlinux", 1996 "/boot/vmlinux" 1997 }; 1998 1999 static const char * const vmlinux_paths_upd[] = { 2000 "/boot/vmlinux-%s", 2001 "/usr/lib/debug/boot/vmlinux-%s", 2002 "/lib/modules/%s/build/vmlinux", 2003 "/usr/lib/debug/lib/modules/%s/vmlinux", 2004 "/usr/lib/debug/boot/vmlinux-%s.debug" 2005 }; 2006 2007 static int vmlinux_path__add(const char *new_entry) 2008 { 2009 vmlinux_path[vmlinux_path__nr_entries] = strdup(new_entry); 2010 if (vmlinux_path[vmlinux_path__nr_entries] == NULL) 2011 return -1; 2012 ++vmlinux_path__nr_entries; 2013 2014 return 0; 2015 } 2016 2017 static int vmlinux_path__init(struct perf_env *env) 2018 { 2019 struct utsname uts; 2020 char bf[PATH_MAX]; 2021 char *kernel_version; 2022 unsigned int i; 2023 2024 vmlinux_path = malloc(sizeof(char *) * (ARRAY_SIZE(vmlinux_paths) + 2025 ARRAY_SIZE(vmlinux_paths_upd))); 2026 if (vmlinux_path == NULL) 2027 return -1; 2028 2029 for (i = 0; i < ARRAY_SIZE(vmlinux_paths); i++) 2030 if (vmlinux_path__add(vmlinux_paths[i]) < 0) 2031 goto out_fail; 2032 2033 /* only try kernel version if no symfs was given */ 2034 if (symbol_conf.symfs[0] != 0) 2035 return 0; 2036 2037 if (env) { 2038 kernel_version = env->os_release; 2039 } else { 2040 if (uname(&uts) < 0) 2041 goto out_fail; 2042 2043 kernel_version = uts.release; 2044 } 2045 2046 for (i = 0; i < ARRAY_SIZE(vmlinux_paths_upd); i++) { 2047 snprintf(bf, sizeof(bf), vmlinux_paths_upd[i], kernel_version); 2048 if (vmlinux_path__add(bf) < 0) 2049 goto out_fail; 2050 } 2051 2052 return 0; 2053 2054 out_fail: 2055 vmlinux_path__exit(); 2056 return -1; 2057 } 2058 2059 int setup_list(struct strlist **list, const char *list_str, 2060 const char *list_name) 2061 { 2062 if (list_str == NULL) 2063 return 0; 2064 2065 *list = strlist__new(list_str, NULL); 2066 if (!*list) { 2067 pr_err("problems parsing %s list\n", list_name); 2068 return -1; 2069 } 2070 2071 symbol_conf.has_filter = true; 2072 return 0; 2073 } 2074 2075 int setup_intlist(struct intlist **list, const char *list_str, 2076 const char *list_name) 2077 { 2078 if (list_str == NULL) 2079 return 0; 2080 2081 *list = intlist__new(list_str); 2082 if (!*list) { 2083 pr_err("problems parsing %s list\n", list_name); 2084 return -1; 2085 } 2086 return 0; 2087 } 2088 2089 static bool symbol__read_kptr_restrict(void) 2090 { 2091 bool value = false; 2092 FILE *fp = fopen("/proc/sys/kernel/kptr_restrict", "r"); 2093 2094 if (fp != NULL) { 2095 char line[8]; 2096 2097 if (fgets(line, sizeof(line), fp) != NULL) 2098 value = ((geteuid() != 0) || (getuid() != 0)) ? 2099 (atoi(line) != 0) : 2100 (atoi(line) == 2); 2101 2102 fclose(fp); 2103 } 2104 2105 return value; 2106 } 2107 2108 int symbol__annotation_init(void) 2109 { 2110 if (symbol_conf.init_annotation) 2111 return 0; 2112 2113 if (symbol_conf.initialized) { 2114 pr_err("Annotation needs to be init before symbol__init()\n"); 2115 return -1; 2116 } 2117 2118 symbol_conf.priv_size += sizeof(struct annotation); 2119 symbol_conf.init_annotation = true; 2120 return 0; 2121 } 2122 2123 int symbol__init(struct perf_env *env) 2124 { 2125 const char *symfs; 2126 2127 if (symbol_conf.initialized) 2128 return 0; 2129 2130 symbol_conf.priv_size = PERF_ALIGN(symbol_conf.priv_size, sizeof(u64)); 2131 2132 symbol__elf_init(); 2133 2134 if (symbol_conf.sort_by_name) 2135 symbol_conf.priv_size += (sizeof(struct symbol_name_rb_node) - 2136 sizeof(struct symbol)); 2137 2138 if (symbol_conf.try_vmlinux_path && vmlinux_path__init(env) < 0) 2139 return -1; 2140 2141 if (symbol_conf.field_sep && *symbol_conf.field_sep == '.') { 2142 pr_err("'.' is the only non valid --field-separator argument\n"); 2143 return -1; 2144 } 2145 2146 if (setup_list(&symbol_conf.dso_list, 2147 symbol_conf.dso_list_str, "dso") < 0) 2148 return -1; 2149 2150 if (setup_list(&symbol_conf.comm_list, 2151 symbol_conf.comm_list_str, "comm") < 0) 2152 goto out_free_dso_list; 2153 2154 if (setup_intlist(&symbol_conf.pid_list, 2155 symbol_conf.pid_list_str, "pid") < 0) 2156 goto out_free_comm_list; 2157 2158 if (setup_intlist(&symbol_conf.tid_list, 2159 symbol_conf.tid_list_str, "tid") < 0) 2160 goto out_free_pid_list; 2161 2162 if (setup_list(&symbol_conf.sym_list, 2163 symbol_conf.sym_list_str, "symbol") < 0) 2164 goto out_free_tid_list; 2165 2166 if (setup_list(&symbol_conf.bt_stop_list, 2167 symbol_conf.bt_stop_list_str, "symbol") < 0) 2168 goto out_free_sym_list; 2169 2170 /* 2171 * A path to symbols of "/" is identical to "" 2172 * reset here for simplicity. 2173 */ 2174 symfs = realpath(symbol_conf.symfs, NULL); 2175 if (symfs == NULL) 2176 symfs = symbol_conf.symfs; 2177 if (strcmp(symfs, "/") == 0) 2178 symbol_conf.symfs = ""; 2179 if (symfs != symbol_conf.symfs) 2180 free((void *)symfs); 2181 2182 symbol_conf.kptr_restrict = symbol__read_kptr_restrict(); 2183 2184 symbol_conf.initialized = true; 2185 return 0; 2186 2187 out_free_sym_list: 2188 strlist__delete(symbol_conf.sym_list); 2189 out_free_tid_list: 2190 intlist__delete(symbol_conf.tid_list); 2191 out_free_pid_list: 2192 intlist__delete(symbol_conf.pid_list); 2193 out_free_comm_list: 2194 strlist__delete(symbol_conf.comm_list); 2195 out_free_dso_list: 2196 strlist__delete(symbol_conf.dso_list); 2197 return -1; 2198 } 2199 2200 void symbol__exit(void) 2201 { 2202 if (!symbol_conf.initialized) 2203 return; 2204 strlist__delete(symbol_conf.bt_stop_list); 2205 strlist__delete(symbol_conf.sym_list); 2206 strlist__delete(symbol_conf.dso_list); 2207 strlist__delete(symbol_conf.comm_list); 2208 intlist__delete(symbol_conf.tid_list); 2209 intlist__delete(symbol_conf.pid_list); 2210 vmlinux_path__exit(); 2211 symbol_conf.sym_list = symbol_conf.dso_list = symbol_conf.comm_list = NULL; 2212 symbol_conf.bt_stop_list = NULL; 2213 symbol_conf.initialized = false; 2214 } 2215 2216 int symbol__config_symfs(const struct option *opt __maybe_unused, 2217 const char *dir, int unset __maybe_unused) 2218 { 2219 char *bf = NULL; 2220 int ret; 2221 2222 symbol_conf.symfs = strdup(dir); 2223 if (symbol_conf.symfs == NULL) 2224 return -ENOMEM; 2225 2226 /* skip the locally configured cache if a symfs is given, and 2227 * config buildid dir to symfs/.debug 2228 */ 2229 ret = asprintf(&bf, "%s/%s", dir, ".debug"); 2230 if (ret < 0) 2231 return -ENOMEM; 2232 2233 set_buildid_dir(bf); 2234 2235 free(bf); 2236 return 0; 2237 } 2238 2239 struct mem_info *mem_info__get(struct mem_info *mi) 2240 { 2241 if (mi) 2242 refcount_inc(&mi->refcnt); 2243 return mi; 2244 } 2245 2246 void mem_info__put(struct mem_info *mi) 2247 { 2248 if (mi && refcount_dec_and_test(&mi->refcnt)) 2249 free(mi); 2250 } 2251 2252 struct mem_info *mem_info__new(void) 2253 { 2254 struct mem_info *mi = zalloc(sizeof(*mi)); 2255 2256 if (mi) 2257 refcount_set(&mi->refcnt, 1); 2258 return mi; 2259 } 2260