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 <linux/time64.h> 10 #include <sys/types.h> 11 #include <sys/stat.h> 12 #include <sys/param.h> 13 #include <fcntl.h> 14 #include <unistd.h> 15 #include <inttypes.h> 16 #include "annotate.h" 17 #include "build-id.h" 18 #include "util.h" 19 #include "debug.h" 20 #include "machine.h" 21 #include "map.h" 22 #include "symbol.h" 23 #include "strlist.h" 24 #include "intlist.h" 25 #include "namespaces.h" 26 #include "header.h" 27 #include "path.h" 28 #include "sane_ctype.h" 29 30 #include <elf.h> 31 #include <limits.h> 32 #include <symbol/kallsyms.h> 33 #include <sys/utsname.h> 34 35 static int dso__load_kernel_sym(struct dso *dso, struct map *map); 36 static int dso__load_guest_kernel_sym(struct dso *dso, struct map *map); 37 static bool symbol__is_idle(const char *name); 38 39 int vmlinux_path__nr_entries; 40 char **vmlinux_path; 41 42 struct symbol_conf symbol_conf = { 43 .nanosecs = false, 44 .use_modules = true, 45 .try_vmlinux_path = true, 46 .demangle = true, 47 .demangle_kernel = false, 48 .cumulate_callchain = true, 49 .time_quantum = 100 * NSEC_PER_MSEC, /* 100ms */ 50 .show_hist_headers = true, 51 .symfs = "", 52 .event_group = true, 53 .inline_name = true, 54 .res_sample = 0, 55 }; 56 57 static enum dso_binary_type binary_type_symtab[] = { 58 DSO_BINARY_TYPE__KALLSYMS, 59 DSO_BINARY_TYPE__GUEST_KALLSYMS, 60 DSO_BINARY_TYPE__JAVA_JIT, 61 DSO_BINARY_TYPE__DEBUGLINK, 62 DSO_BINARY_TYPE__BUILD_ID_CACHE, 63 DSO_BINARY_TYPE__BUILD_ID_CACHE_DEBUGINFO, 64 DSO_BINARY_TYPE__FEDORA_DEBUGINFO, 65 DSO_BINARY_TYPE__UBUNTU_DEBUGINFO, 66 DSO_BINARY_TYPE__BUILDID_DEBUGINFO, 67 DSO_BINARY_TYPE__SYSTEM_PATH_DSO, 68 DSO_BINARY_TYPE__GUEST_KMODULE, 69 DSO_BINARY_TYPE__GUEST_KMODULE_COMP, 70 DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE, 71 DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP, 72 DSO_BINARY_TYPE__OPENEMBEDDED_DEBUGINFO, 73 DSO_BINARY_TYPE__NOT_FOUND, 74 }; 75 76 #define DSO_BINARY_TYPE__SYMTAB_CNT ARRAY_SIZE(binary_type_symtab) 77 78 static bool symbol_type__filter(char symbol_type) 79 { 80 symbol_type = toupper(symbol_type); 81 return symbol_type == 'T' || symbol_type == 'W' || symbol_type == 'D' || symbol_type == 'B'; 82 } 83 84 static int prefix_underscores_count(const char *str) 85 { 86 const char *tail = str; 87 88 while (*tail == '_') 89 tail++; 90 91 return tail - str; 92 } 93 94 const char * __weak arch__normalize_symbol_name(const char *name) 95 { 96 return name; 97 } 98 99 int __weak arch__compare_symbol_names(const char *namea, const char *nameb) 100 { 101 return strcmp(namea, nameb); 102 } 103 104 int __weak arch__compare_symbol_names_n(const char *namea, const char *nameb, 105 unsigned int n) 106 { 107 return strncmp(namea, nameb, n); 108 } 109 110 int __weak arch__choose_best_symbol(struct symbol *syma, 111 struct symbol *symb __maybe_unused) 112 { 113 /* Avoid "SyS" kernel syscall aliases */ 114 if (strlen(syma->name) >= 3 && !strncmp(syma->name, "SyS", 3)) 115 return SYMBOL_B; 116 if (strlen(syma->name) >= 10 && !strncmp(syma->name, "compat_SyS", 10)) 117 return SYMBOL_B; 118 119 return SYMBOL_A; 120 } 121 122 static int choose_best_symbol(struct symbol *syma, struct symbol *symb) 123 { 124 s64 a; 125 s64 b; 126 size_t na, nb; 127 128 /* Prefer a symbol with non zero length */ 129 a = syma->end - syma->start; 130 b = symb->end - symb->start; 131 if ((b == 0) && (a > 0)) 132 return SYMBOL_A; 133 else if ((a == 0) && (b > 0)) 134 return SYMBOL_B; 135 136 /* Prefer a non weak symbol over a weak one */ 137 a = syma->binding == STB_WEAK; 138 b = symb->binding == STB_WEAK; 139 if (b && !a) 140 return SYMBOL_A; 141 if (a && !b) 142 return SYMBOL_B; 143 144 /* Prefer a global symbol over a non global one */ 145 a = syma->binding == STB_GLOBAL; 146 b = symb->binding == STB_GLOBAL; 147 if (a && !b) 148 return SYMBOL_A; 149 if (b && !a) 150 return SYMBOL_B; 151 152 /* Prefer a symbol with less underscores */ 153 a = prefix_underscores_count(syma->name); 154 b = prefix_underscores_count(symb->name); 155 if (b > a) 156 return SYMBOL_A; 157 else if (a > b) 158 return SYMBOL_B; 159 160 /* Choose the symbol with the longest name */ 161 na = strlen(syma->name); 162 nb = strlen(symb->name); 163 if (na > nb) 164 return SYMBOL_A; 165 else if (na < nb) 166 return SYMBOL_B; 167 168 return arch__choose_best_symbol(syma, symb); 169 } 170 171 void symbols__fixup_duplicate(struct rb_root_cached *symbols) 172 { 173 struct rb_node *nd; 174 struct symbol *curr, *next; 175 176 if (symbol_conf.allow_aliases) 177 return; 178 179 nd = rb_first_cached(symbols); 180 181 while (nd) { 182 curr = rb_entry(nd, struct symbol, rb_node); 183 again: 184 nd = rb_next(&curr->rb_node); 185 next = rb_entry(nd, struct symbol, rb_node); 186 187 if (!nd) 188 break; 189 190 if (curr->start != next->start) 191 continue; 192 193 if (choose_best_symbol(curr, next) == SYMBOL_A) { 194 rb_erase_cached(&next->rb_node, symbols); 195 symbol__delete(next); 196 goto again; 197 } else { 198 nd = rb_next(&curr->rb_node); 199 rb_erase_cached(&curr->rb_node, symbols); 200 symbol__delete(curr); 201 } 202 } 203 } 204 205 void symbols__fixup_end(struct rb_root_cached *symbols) 206 { 207 struct rb_node *nd, *prevnd = rb_first_cached(symbols); 208 struct symbol *curr, *prev; 209 210 if (prevnd == NULL) 211 return; 212 213 curr = rb_entry(prevnd, struct symbol, rb_node); 214 215 for (nd = rb_next(prevnd); nd; nd = rb_next(nd)) { 216 prev = curr; 217 curr = rb_entry(nd, struct symbol, rb_node); 218 219 if (prev->end == prev->start && prev->end != curr->start) 220 prev->end = curr->start; 221 } 222 223 /* Last entry */ 224 if (curr->end == curr->start) 225 curr->end = roundup(curr->start, 4096) + 4096; 226 } 227 228 void map_groups__fixup_end(struct map_groups *mg) 229 { 230 struct maps *maps = &mg->maps; 231 struct map *next, *curr; 232 233 down_write(&maps->lock); 234 235 curr = maps__first(maps); 236 if (curr == NULL) 237 goto out_unlock; 238 239 for (next = map__next(curr); next; next = map__next(curr)) { 240 if (!curr->end) 241 curr->end = next->start; 242 curr = next; 243 } 244 245 /* 246 * We still haven't the actual symbols, so guess the 247 * last map final address. 248 */ 249 if (!curr->end) 250 curr->end = ~0ULL; 251 252 out_unlock: 253 up_write(&maps->lock); 254 } 255 256 struct symbol *symbol__new(u64 start, u64 len, u8 binding, u8 type, const char *name) 257 { 258 size_t namelen = strlen(name) + 1; 259 struct symbol *sym = calloc(1, (symbol_conf.priv_size + 260 sizeof(*sym) + namelen)); 261 if (sym == NULL) 262 return NULL; 263 264 if (symbol_conf.priv_size) { 265 if (symbol_conf.init_annotation) { 266 struct annotation *notes = (void *)sym; 267 pthread_mutex_init(¬es->lock, NULL); 268 } 269 sym = ((void *)sym) + symbol_conf.priv_size; 270 } 271 272 sym->start = start; 273 sym->end = len ? start + len : start; 274 sym->type = type; 275 sym->binding = binding; 276 sym->namelen = namelen - 1; 277 278 pr_debug4("%s: %s %#" PRIx64 "-%#" PRIx64 "\n", 279 __func__, name, start, sym->end); 280 memcpy(sym->name, name, namelen); 281 282 return sym; 283 } 284 285 void symbol__delete(struct symbol *sym) 286 { 287 free(((void *)sym) - symbol_conf.priv_size); 288 } 289 290 void symbols__delete(struct rb_root_cached *symbols) 291 { 292 struct symbol *pos; 293 struct rb_node *next = rb_first_cached(symbols); 294 295 while (next) { 296 pos = rb_entry(next, struct symbol, rb_node); 297 next = rb_next(&pos->rb_node); 298 rb_erase_cached(&pos->rb_node, symbols); 299 symbol__delete(pos); 300 } 301 } 302 303 void __symbols__insert(struct rb_root_cached *symbols, 304 struct symbol *sym, bool kernel) 305 { 306 struct rb_node **p = &symbols->rb_root.rb_node; 307 struct rb_node *parent = NULL; 308 const u64 ip = sym->start; 309 struct symbol *s; 310 bool leftmost = true; 311 312 if (kernel) { 313 const char *name = sym->name; 314 /* 315 * ppc64 uses function descriptors and appends a '.' to the 316 * start of every instruction address. Remove it. 317 */ 318 if (name[0] == '.') 319 name++; 320 sym->idle = symbol__is_idle(name); 321 } 322 323 while (*p != NULL) { 324 parent = *p; 325 s = rb_entry(parent, struct symbol, rb_node); 326 if (ip < s->start) 327 p = &(*p)->rb_left; 328 else { 329 p = &(*p)->rb_right; 330 leftmost = false; 331 } 332 } 333 rb_link_node(&sym->rb_node, parent, p); 334 rb_insert_color_cached(&sym->rb_node, symbols, leftmost); 335 } 336 337 void symbols__insert(struct rb_root_cached *symbols, struct symbol *sym) 338 { 339 __symbols__insert(symbols, sym, false); 340 } 341 342 static struct symbol *symbols__find(struct rb_root_cached *symbols, u64 ip) 343 { 344 struct rb_node *n; 345 346 if (symbols == NULL) 347 return NULL; 348 349 n = symbols->rb_root.rb_node; 350 351 while (n) { 352 struct symbol *s = rb_entry(n, struct symbol, rb_node); 353 354 if (ip < s->start) 355 n = n->rb_left; 356 else if (ip > s->end || (ip == s->end && ip != s->start)) 357 n = n->rb_right; 358 else 359 return s; 360 } 361 362 return NULL; 363 } 364 365 static struct symbol *symbols__first(struct rb_root_cached *symbols) 366 { 367 struct rb_node *n = rb_first_cached(symbols); 368 369 if (n) 370 return rb_entry(n, struct symbol, rb_node); 371 372 return NULL; 373 } 374 375 static struct symbol *symbols__last(struct rb_root_cached *symbols) 376 { 377 struct rb_node *n = rb_last(&symbols->rb_root); 378 379 if (n) 380 return rb_entry(n, struct symbol, rb_node); 381 382 return NULL; 383 } 384 385 static struct symbol *symbols__next(struct symbol *sym) 386 { 387 struct rb_node *n = rb_next(&sym->rb_node); 388 389 if (n) 390 return rb_entry(n, struct symbol, rb_node); 391 392 return NULL; 393 } 394 395 static void symbols__insert_by_name(struct rb_root_cached *symbols, struct symbol *sym) 396 { 397 struct rb_node **p = &symbols->rb_root.rb_node; 398 struct rb_node *parent = NULL; 399 struct symbol_name_rb_node *symn, *s; 400 bool leftmost = true; 401 402 symn = container_of(sym, struct symbol_name_rb_node, sym); 403 404 while (*p != NULL) { 405 parent = *p; 406 s = rb_entry(parent, struct symbol_name_rb_node, rb_node); 407 if (strcmp(sym->name, s->sym.name) < 0) 408 p = &(*p)->rb_left; 409 else { 410 p = &(*p)->rb_right; 411 leftmost = false; 412 } 413 } 414 rb_link_node(&symn->rb_node, parent, p); 415 rb_insert_color_cached(&symn->rb_node, symbols, leftmost); 416 } 417 418 static void symbols__sort_by_name(struct rb_root_cached *symbols, 419 struct rb_root_cached *source) 420 { 421 struct rb_node *nd; 422 423 for (nd = rb_first_cached(source); nd; nd = rb_next(nd)) { 424 struct symbol *pos = rb_entry(nd, struct symbol, rb_node); 425 symbols__insert_by_name(symbols, pos); 426 } 427 } 428 429 int symbol__match_symbol_name(const char *name, const char *str, 430 enum symbol_tag_include includes) 431 { 432 const char *versioning; 433 434 if (includes == SYMBOL_TAG_INCLUDE__DEFAULT_ONLY && 435 (versioning = strstr(name, "@@"))) { 436 int len = strlen(str); 437 438 if (len < versioning - name) 439 len = versioning - name; 440 441 return arch__compare_symbol_names_n(name, str, len); 442 } else 443 return arch__compare_symbol_names(name, str); 444 } 445 446 static struct symbol *symbols__find_by_name(struct rb_root_cached *symbols, 447 const char *name, 448 enum symbol_tag_include includes) 449 { 450 struct rb_node *n; 451 struct symbol_name_rb_node *s = NULL; 452 453 if (symbols == NULL) 454 return NULL; 455 456 n = symbols->rb_root.rb_node; 457 458 while (n) { 459 int cmp; 460 461 s = rb_entry(n, struct symbol_name_rb_node, rb_node); 462 cmp = symbol__match_symbol_name(s->sym.name, name, includes); 463 464 if (cmp > 0) 465 n = n->rb_left; 466 else if (cmp < 0) 467 n = n->rb_right; 468 else 469 break; 470 } 471 472 if (n == NULL) 473 return NULL; 474 475 if (includes != SYMBOL_TAG_INCLUDE__DEFAULT_ONLY) 476 /* return first symbol that has same name (if any) */ 477 for (n = rb_prev(n); n; n = rb_prev(n)) { 478 struct symbol_name_rb_node *tmp; 479 480 tmp = rb_entry(n, struct symbol_name_rb_node, rb_node); 481 if (arch__compare_symbol_names(tmp->sym.name, s->sym.name)) 482 break; 483 484 s = tmp; 485 } 486 487 return &s->sym; 488 } 489 490 void dso__reset_find_symbol_cache(struct dso *dso) 491 { 492 dso->last_find_result.addr = 0; 493 dso->last_find_result.symbol = NULL; 494 } 495 496 void dso__insert_symbol(struct dso *dso, struct symbol *sym) 497 { 498 __symbols__insert(&dso->symbols, sym, dso->kernel); 499 500 /* update the symbol cache if necessary */ 501 if (dso->last_find_result.addr >= sym->start && 502 (dso->last_find_result.addr < sym->end || 503 sym->start == sym->end)) { 504 dso->last_find_result.symbol = sym; 505 } 506 } 507 508 struct symbol *dso__find_symbol(struct dso *dso, u64 addr) 509 { 510 if (dso->last_find_result.addr != addr || dso->last_find_result.symbol == NULL) { 511 dso->last_find_result.addr = addr; 512 dso->last_find_result.symbol = symbols__find(&dso->symbols, addr); 513 } 514 515 return dso->last_find_result.symbol; 516 } 517 518 struct symbol *dso__first_symbol(struct dso *dso) 519 { 520 return symbols__first(&dso->symbols); 521 } 522 523 struct symbol *dso__last_symbol(struct dso *dso) 524 { 525 return symbols__last(&dso->symbols); 526 } 527 528 struct symbol *dso__next_symbol(struct symbol *sym) 529 { 530 return symbols__next(sym); 531 } 532 533 struct symbol *symbol__next_by_name(struct symbol *sym) 534 { 535 struct symbol_name_rb_node *s = container_of(sym, struct symbol_name_rb_node, sym); 536 struct rb_node *n = rb_next(&s->rb_node); 537 538 return n ? &rb_entry(n, struct symbol_name_rb_node, rb_node)->sym : NULL; 539 } 540 541 /* 542 * Returns first symbol that matched with @name. 543 */ 544 struct symbol *dso__find_symbol_by_name(struct dso *dso, const char *name) 545 { 546 struct symbol *s = symbols__find_by_name(&dso->symbol_names, name, 547 SYMBOL_TAG_INCLUDE__NONE); 548 if (!s) 549 s = symbols__find_by_name(&dso->symbol_names, name, 550 SYMBOL_TAG_INCLUDE__DEFAULT_ONLY); 551 return s; 552 } 553 554 void dso__sort_by_name(struct dso *dso) 555 { 556 dso__set_sorted_by_name(dso); 557 return symbols__sort_by_name(&dso->symbol_names, &dso->symbols); 558 } 559 560 int modules__parse(const char *filename, void *arg, 561 int (*process_module)(void *arg, const char *name, 562 u64 start, u64 size)) 563 { 564 char *line = NULL; 565 size_t n; 566 FILE *file; 567 int err = 0; 568 569 file = fopen(filename, "r"); 570 if (file == NULL) 571 return -1; 572 573 while (1) { 574 char name[PATH_MAX]; 575 u64 start, size; 576 char *sep, *endptr; 577 ssize_t line_len; 578 579 line_len = getline(&line, &n, file); 580 if (line_len < 0) { 581 if (feof(file)) 582 break; 583 err = -1; 584 goto out; 585 } 586 587 if (!line) { 588 err = -1; 589 goto out; 590 } 591 592 line[--line_len] = '\0'; /* \n */ 593 594 sep = strrchr(line, 'x'); 595 if (sep == NULL) 596 continue; 597 598 hex2u64(sep + 1, &start); 599 600 sep = strchr(line, ' '); 601 if (sep == NULL) 602 continue; 603 604 *sep = '\0'; 605 606 scnprintf(name, sizeof(name), "[%s]", line); 607 608 size = strtoul(sep + 1, &endptr, 0); 609 if (*endptr != ' ' && *endptr != '\t') 610 continue; 611 612 err = process_module(arg, name, start, size); 613 if (err) 614 break; 615 } 616 out: 617 free(line); 618 fclose(file); 619 return err; 620 } 621 622 /* 623 * These are symbols in the kernel image, so make sure that 624 * sym is from a kernel DSO. 625 */ 626 static bool symbol__is_idle(const char *name) 627 { 628 const char * const idle_symbols[] = { 629 "arch_cpu_idle", 630 "cpu_idle", 631 "cpu_startup_entry", 632 "intel_idle", 633 "default_idle", 634 "native_safe_halt", 635 "enter_idle", 636 "exit_idle", 637 "mwait_idle", 638 "mwait_idle_with_hints", 639 "poll_idle", 640 "ppc64_runlatch_off", 641 "pseries_dedicated_idle_sleep", 642 NULL 643 }; 644 int i; 645 646 for (i = 0; idle_symbols[i]; i++) { 647 if (!strcmp(idle_symbols[i], name)) 648 return true; 649 } 650 651 return false; 652 } 653 654 static int map__process_kallsym_symbol(void *arg, const char *name, 655 char type, u64 start) 656 { 657 struct symbol *sym; 658 struct dso *dso = arg; 659 struct rb_root_cached *root = &dso->symbols; 660 661 if (!symbol_type__filter(type)) 662 return 0; 663 664 /* 665 * module symbols are not sorted so we add all 666 * symbols, setting length to 0, and rely on 667 * symbols__fixup_end() to fix it up. 668 */ 669 sym = symbol__new(start, 0, kallsyms2elf_binding(type), kallsyms2elf_type(type), name); 670 if (sym == NULL) 671 return -ENOMEM; 672 /* 673 * We will pass the symbols to the filter later, in 674 * map__split_kallsyms, when we have split the maps per module 675 */ 676 __symbols__insert(root, sym, !strchr(name, '[')); 677 678 return 0; 679 } 680 681 /* 682 * Loads the function entries in /proc/kallsyms into kernel_map->dso, 683 * so that we can in the next step set the symbol ->end address and then 684 * call kernel_maps__split_kallsyms. 685 */ 686 static int dso__load_all_kallsyms(struct dso *dso, const char *filename) 687 { 688 return kallsyms__parse(filename, dso, map__process_kallsym_symbol); 689 } 690 691 static int map_groups__split_kallsyms_for_kcore(struct map_groups *kmaps, struct dso *dso) 692 { 693 struct map *curr_map; 694 struct symbol *pos; 695 int count = 0; 696 struct rb_root_cached old_root = dso->symbols; 697 struct rb_root_cached *root = &dso->symbols; 698 struct rb_node *next = rb_first_cached(root); 699 700 if (!kmaps) 701 return -1; 702 703 *root = RB_ROOT_CACHED; 704 705 while (next) { 706 char *module; 707 708 pos = rb_entry(next, struct symbol, rb_node); 709 next = rb_next(&pos->rb_node); 710 711 rb_erase_cached(&pos->rb_node, &old_root); 712 RB_CLEAR_NODE(&pos->rb_node); 713 module = strchr(pos->name, '\t'); 714 if (module) 715 *module = '\0'; 716 717 curr_map = map_groups__find(kmaps, pos->start); 718 719 if (!curr_map) { 720 symbol__delete(pos); 721 continue; 722 } 723 724 pos->start -= curr_map->start - curr_map->pgoff; 725 if (pos->end > curr_map->end) 726 pos->end = curr_map->end; 727 if (pos->end) 728 pos->end -= curr_map->start - curr_map->pgoff; 729 symbols__insert(&curr_map->dso->symbols, pos); 730 ++count; 731 } 732 733 /* Symbols have been adjusted */ 734 dso->adjust_symbols = 1; 735 736 return count; 737 } 738 739 /* 740 * Split the symbols into maps, making sure there are no overlaps, i.e. the 741 * kernel range is broken in several maps, named [kernel].N, as we don't have 742 * the original ELF section names vmlinux have. 743 */ 744 static int map_groups__split_kallsyms(struct map_groups *kmaps, struct dso *dso, u64 delta, 745 struct map *initial_map) 746 { 747 struct machine *machine; 748 struct map *curr_map = initial_map; 749 struct symbol *pos; 750 int count = 0, moved = 0; 751 struct rb_root_cached *root = &dso->symbols; 752 struct rb_node *next = rb_first_cached(root); 753 int kernel_range = 0; 754 bool x86_64; 755 756 if (!kmaps) 757 return -1; 758 759 machine = kmaps->machine; 760 761 x86_64 = machine__is(machine, "x86_64"); 762 763 while (next) { 764 char *module; 765 766 pos = rb_entry(next, struct symbol, rb_node); 767 next = rb_next(&pos->rb_node); 768 769 module = strchr(pos->name, '\t'); 770 if (module) { 771 if (!symbol_conf.use_modules) 772 goto discard_symbol; 773 774 *module++ = '\0'; 775 776 if (strcmp(curr_map->dso->short_name, module)) { 777 if (curr_map != initial_map && 778 dso->kernel == DSO_TYPE_GUEST_KERNEL && 779 machine__is_default_guest(machine)) { 780 /* 781 * We assume all symbols of a module are 782 * continuous in * kallsyms, so curr_map 783 * points to a module and all its 784 * symbols are in its kmap. Mark it as 785 * loaded. 786 */ 787 dso__set_loaded(curr_map->dso); 788 } 789 790 curr_map = map_groups__find_by_name(kmaps, module); 791 if (curr_map == NULL) { 792 pr_debug("%s/proc/{kallsyms,modules} " 793 "inconsistency while looking " 794 "for \"%s\" module!\n", 795 machine->root_dir, module); 796 curr_map = initial_map; 797 goto discard_symbol; 798 } 799 800 if (curr_map->dso->loaded && 801 !machine__is_default_guest(machine)) 802 goto discard_symbol; 803 } 804 /* 805 * So that we look just like we get from .ko files, 806 * i.e. not prelinked, relative to initial_map->start. 807 */ 808 pos->start = curr_map->map_ip(curr_map, pos->start); 809 pos->end = curr_map->map_ip(curr_map, pos->end); 810 } else if (x86_64 && is_entry_trampoline(pos->name)) { 811 /* 812 * These symbols are not needed anymore since the 813 * trampoline maps refer to the text section and it's 814 * symbols instead. Avoid having to deal with 815 * relocations, and the assumption that the first symbol 816 * is the start of kernel text, by simply removing the 817 * symbols at this point. 818 */ 819 goto discard_symbol; 820 } else if (curr_map != initial_map) { 821 char dso_name[PATH_MAX]; 822 struct dso *ndso; 823 824 if (delta) { 825 /* Kernel was relocated at boot time */ 826 pos->start -= delta; 827 pos->end -= delta; 828 } 829 830 if (count == 0) { 831 curr_map = initial_map; 832 goto add_symbol; 833 } 834 835 if (dso->kernel == DSO_TYPE_GUEST_KERNEL) 836 snprintf(dso_name, sizeof(dso_name), 837 "[guest.kernel].%d", 838 kernel_range++); 839 else 840 snprintf(dso_name, sizeof(dso_name), 841 "[kernel].%d", 842 kernel_range++); 843 844 ndso = dso__new(dso_name); 845 if (ndso == NULL) 846 return -1; 847 848 ndso->kernel = dso->kernel; 849 850 curr_map = map__new2(pos->start, ndso); 851 if (curr_map == NULL) { 852 dso__put(ndso); 853 return -1; 854 } 855 856 curr_map->map_ip = curr_map->unmap_ip = identity__map_ip; 857 map_groups__insert(kmaps, curr_map); 858 ++kernel_range; 859 } else if (delta) { 860 /* Kernel was relocated at boot time */ 861 pos->start -= delta; 862 pos->end -= delta; 863 } 864 add_symbol: 865 if (curr_map != initial_map) { 866 rb_erase_cached(&pos->rb_node, root); 867 symbols__insert(&curr_map->dso->symbols, pos); 868 ++moved; 869 } else 870 ++count; 871 872 continue; 873 discard_symbol: 874 rb_erase_cached(&pos->rb_node, root); 875 symbol__delete(pos); 876 } 877 878 if (curr_map != initial_map && 879 dso->kernel == DSO_TYPE_GUEST_KERNEL && 880 machine__is_default_guest(kmaps->machine)) { 881 dso__set_loaded(curr_map->dso); 882 } 883 884 return count + moved; 885 } 886 887 bool symbol__restricted_filename(const char *filename, 888 const char *restricted_filename) 889 { 890 bool restricted = false; 891 892 if (symbol_conf.kptr_restrict) { 893 char *r = realpath(filename, NULL); 894 895 if (r != NULL) { 896 restricted = strcmp(r, restricted_filename) == 0; 897 free(r); 898 return restricted; 899 } 900 } 901 902 return restricted; 903 } 904 905 struct module_info { 906 struct rb_node rb_node; 907 char *name; 908 u64 start; 909 }; 910 911 static void add_module(struct module_info *mi, struct rb_root *modules) 912 { 913 struct rb_node **p = &modules->rb_node; 914 struct rb_node *parent = NULL; 915 struct module_info *m; 916 917 while (*p != NULL) { 918 parent = *p; 919 m = rb_entry(parent, struct module_info, rb_node); 920 if (strcmp(mi->name, m->name) < 0) 921 p = &(*p)->rb_left; 922 else 923 p = &(*p)->rb_right; 924 } 925 rb_link_node(&mi->rb_node, parent, p); 926 rb_insert_color(&mi->rb_node, modules); 927 } 928 929 static void delete_modules(struct rb_root *modules) 930 { 931 struct module_info *mi; 932 struct rb_node *next = rb_first(modules); 933 934 while (next) { 935 mi = rb_entry(next, struct module_info, rb_node); 936 next = rb_next(&mi->rb_node); 937 rb_erase(&mi->rb_node, modules); 938 zfree(&mi->name); 939 free(mi); 940 } 941 } 942 943 static struct module_info *find_module(const char *name, 944 struct rb_root *modules) 945 { 946 struct rb_node *n = modules->rb_node; 947 948 while (n) { 949 struct module_info *m; 950 int cmp; 951 952 m = rb_entry(n, struct module_info, rb_node); 953 cmp = strcmp(name, m->name); 954 if (cmp < 0) 955 n = n->rb_left; 956 else if (cmp > 0) 957 n = n->rb_right; 958 else 959 return m; 960 } 961 962 return NULL; 963 } 964 965 static int __read_proc_modules(void *arg, const char *name, u64 start, 966 u64 size __maybe_unused) 967 { 968 struct rb_root *modules = arg; 969 struct module_info *mi; 970 971 mi = zalloc(sizeof(struct module_info)); 972 if (!mi) 973 return -ENOMEM; 974 975 mi->name = strdup(name); 976 mi->start = start; 977 978 if (!mi->name) { 979 free(mi); 980 return -ENOMEM; 981 } 982 983 add_module(mi, modules); 984 985 return 0; 986 } 987 988 static int read_proc_modules(const char *filename, struct rb_root *modules) 989 { 990 if (symbol__restricted_filename(filename, "/proc/modules")) 991 return -1; 992 993 if (modules__parse(filename, modules, __read_proc_modules)) { 994 delete_modules(modules); 995 return -1; 996 } 997 998 return 0; 999 } 1000 1001 int compare_proc_modules(const char *from, const char *to) 1002 { 1003 struct rb_root from_modules = RB_ROOT; 1004 struct rb_root to_modules = RB_ROOT; 1005 struct rb_node *from_node, *to_node; 1006 struct module_info *from_m, *to_m; 1007 int ret = -1; 1008 1009 if (read_proc_modules(from, &from_modules)) 1010 return -1; 1011 1012 if (read_proc_modules(to, &to_modules)) 1013 goto out_delete_from; 1014 1015 from_node = rb_first(&from_modules); 1016 to_node = rb_first(&to_modules); 1017 while (from_node) { 1018 if (!to_node) 1019 break; 1020 1021 from_m = rb_entry(from_node, struct module_info, rb_node); 1022 to_m = rb_entry(to_node, struct module_info, rb_node); 1023 1024 if (from_m->start != to_m->start || 1025 strcmp(from_m->name, to_m->name)) 1026 break; 1027 1028 from_node = rb_next(from_node); 1029 to_node = rb_next(to_node); 1030 } 1031 1032 if (!from_node && !to_node) 1033 ret = 0; 1034 1035 delete_modules(&to_modules); 1036 out_delete_from: 1037 delete_modules(&from_modules); 1038 1039 return ret; 1040 } 1041 1042 struct map *map_groups__first(struct map_groups *mg) 1043 { 1044 return maps__first(&mg->maps); 1045 } 1046 1047 static int do_validate_kcore_modules(const char *filename, 1048 struct map_groups *kmaps) 1049 { 1050 struct rb_root modules = RB_ROOT; 1051 struct map *old_map; 1052 int err; 1053 1054 err = read_proc_modules(filename, &modules); 1055 if (err) 1056 return err; 1057 1058 old_map = map_groups__first(kmaps); 1059 while (old_map) { 1060 struct map *next = map_groups__next(old_map); 1061 struct module_info *mi; 1062 1063 if (!__map__is_kmodule(old_map)) { 1064 old_map = next; 1065 continue; 1066 } 1067 1068 /* Module must be in memory at the same address */ 1069 mi = find_module(old_map->dso->short_name, &modules); 1070 if (!mi || mi->start != old_map->start) { 1071 err = -EINVAL; 1072 goto out; 1073 } 1074 1075 old_map = next; 1076 } 1077 out: 1078 delete_modules(&modules); 1079 return err; 1080 } 1081 1082 /* 1083 * If kallsyms is referenced by name then we look for filename in the same 1084 * directory. 1085 */ 1086 static bool filename_from_kallsyms_filename(char *filename, 1087 const char *base_name, 1088 const char *kallsyms_filename) 1089 { 1090 char *name; 1091 1092 strcpy(filename, kallsyms_filename); 1093 name = strrchr(filename, '/'); 1094 if (!name) 1095 return false; 1096 1097 name += 1; 1098 1099 if (!strcmp(name, "kallsyms")) { 1100 strcpy(name, base_name); 1101 return true; 1102 } 1103 1104 return false; 1105 } 1106 1107 static int validate_kcore_modules(const char *kallsyms_filename, 1108 struct map *map) 1109 { 1110 struct map_groups *kmaps = map__kmaps(map); 1111 char modules_filename[PATH_MAX]; 1112 1113 if (!kmaps) 1114 return -EINVAL; 1115 1116 if (!filename_from_kallsyms_filename(modules_filename, "modules", 1117 kallsyms_filename)) 1118 return -EINVAL; 1119 1120 if (do_validate_kcore_modules(modules_filename, kmaps)) 1121 return -EINVAL; 1122 1123 return 0; 1124 } 1125 1126 static int validate_kcore_addresses(const char *kallsyms_filename, 1127 struct map *map) 1128 { 1129 struct kmap *kmap = map__kmap(map); 1130 1131 if (!kmap) 1132 return -EINVAL; 1133 1134 if (kmap->ref_reloc_sym && kmap->ref_reloc_sym->name) { 1135 u64 start; 1136 1137 if (kallsyms__get_function_start(kallsyms_filename, 1138 kmap->ref_reloc_sym->name, &start)) 1139 return -ENOENT; 1140 if (start != kmap->ref_reloc_sym->addr) 1141 return -EINVAL; 1142 } 1143 1144 return validate_kcore_modules(kallsyms_filename, map); 1145 } 1146 1147 struct kcore_mapfn_data { 1148 struct dso *dso; 1149 struct list_head maps; 1150 }; 1151 1152 static int kcore_mapfn(u64 start, u64 len, u64 pgoff, void *data) 1153 { 1154 struct kcore_mapfn_data *md = data; 1155 struct map *map; 1156 1157 map = map__new2(start, md->dso); 1158 if (map == NULL) 1159 return -ENOMEM; 1160 1161 map->end = map->start + len; 1162 map->pgoff = pgoff; 1163 1164 list_add(&map->node, &md->maps); 1165 1166 return 0; 1167 } 1168 1169 static int dso__load_kcore(struct dso *dso, struct map *map, 1170 const char *kallsyms_filename) 1171 { 1172 struct map_groups *kmaps = map__kmaps(map); 1173 struct kcore_mapfn_data md; 1174 struct map *old_map, *new_map, *replacement_map = NULL; 1175 struct machine *machine; 1176 bool is_64_bit; 1177 int err, fd; 1178 char kcore_filename[PATH_MAX]; 1179 u64 stext; 1180 1181 if (!kmaps) 1182 return -EINVAL; 1183 1184 machine = kmaps->machine; 1185 1186 /* This function requires that the map is the kernel map */ 1187 if (!__map__is_kernel(map)) 1188 return -EINVAL; 1189 1190 if (!filename_from_kallsyms_filename(kcore_filename, "kcore", 1191 kallsyms_filename)) 1192 return -EINVAL; 1193 1194 /* Modules and kernel must be present at their original addresses */ 1195 if (validate_kcore_addresses(kallsyms_filename, map)) 1196 return -EINVAL; 1197 1198 md.dso = dso; 1199 INIT_LIST_HEAD(&md.maps); 1200 1201 fd = open(kcore_filename, O_RDONLY); 1202 if (fd < 0) { 1203 pr_debug("Failed to open %s. Note /proc/kcore requires CAP_SYS_RAWIO capability to access.\n", 1204 kcore_filename); 1205 return -EINVAL; 1206 } 1207 1208 /* Read new maps into temporary lists */ 1209 err = file__read_maps(fd, map->prot & PROT_EXEC, kcore_mapfn, &md, 1210 &is_64_bit); 1211 if (err) 1212 goto out_err; 1213 dso->is_64_bit = is_64_bit; 1214 1215 if (list_empty(&md.maps)) { 1216 err = -EINVAL; 1217 goto out_err; 1218 } 1219 1220 /* Remove old maps */ 1221 old_map = map_groups__first(kmaps); 1222 while (old_map) { 1223 struct map *next = map_groups__next(old_map); 1224 1225 if (old_map != map) 1226 map_groups__remove(kmaps, old_map); 1227 old_map = next; 1228 } 1229 machine->trampolines_mapped = false; 1230 1231 /* Find the kernel map using the '_stext' symbol */ 1232 if (!kallsyms__get_function_start(kallsyms_filename, "_stext", &stext)) { 1233 list_for_each_entry(new_map, &md.maps, node) { 1234 if (stext >= new_map->start && stext < new_map->end) { 1235 replacement_map = new_map; 1236 break; 1237 } 1238 } 1239 } 1240 1241 if (!replacement_map) 1242 replacement_map = list_entry(md.maps.next, struct map, node); 1243 1244 /* Add new maps */ 1245 while (!list_empty(&md.maps)) { 1246 new_map = list_entry(md.maps.next, struct map, node); 1247 list_del_init(&new_map->node); 1248 if (new_map == replacement_map) { 1249 map->start = new_map->start; 1250 map->end = new_map->end; 1251 map->pgoff = new_map->pgoff; 1252 map->map_ip = new_map->map_ip; 1253 map->unmap_ip = new_map->unmap_ip; 1254 /* Ensure maps are correctly ordered */ 1255 map__get(map); 1256 map_groups__remove(kmaps, map); 1257 map_groups__insert(kmaps, map); 1258 map__put(map); 1259 } else { 1260 map_groups__insert(kmaps, new_map); 1261 } 1262 1263 map__put(new_map); 1264 } 1265 1266 if (machine__is(machine, "x86_64")) { 1267 u64 addr; 1268 1269 /* 1270 * If one of the corresponding symbols is there, assume the 1271 * entry trampoline maps are too. 1272 */ 1273 if (!kallsyms__get_function_start(kallsyms_filename, 1274 ENTRY_TRAMPOLINE_NAME, 1275 &addr)) 1276 machine->trampolines_mapped = true; 1277 } 1278 1279 /* 1280 * Set the data type and long name so that kcore can be read via 1281 * dso__data_read_addr(). 1282 */ 1283 if (dso->kernel == DSO_TYPE_GUEST_KERNEL) 1284 dso->binary_type = DSO_BINARY_TYPE__GUEST_KCORE; 1285 else 1286 dso->binary_type = DSO_BINARY_TYPE__KCORE; 1287 dso__set_long_name(dso, strdup(kcore_filename), true); 1288 1289 close(fd); 1290 1291 if (map->prot & PROT_EXEC) 1292 pr_debug("Using %s for kernel object code\n", kcore_filename); 1293 else 1294 pr_debug("Using %s for kernel data\n", kcore_filename); 1295 1296 return 0; 1297 1298 out_err: 1299 while (!list_empty(&md.maps)) { 1300 map = list_entry(md.maps.next, struct map, node); 1301 list_del_init(&map->node); 1302 map__put(map); 1303 } 1304 close(fd); 1305 return -EINVAL; 1306 } 1307 1308 /* 1309 * If the kernel is relocated at boot time, kallsyms won't match. Compute the 1310 * delta based on the relocation reference symbol. 1311 */ 1312 static int kallsyms__delta(struct kmap *kmap, const char *filename, u64 *delta) 1313 { 1314 u64 addr; 1315 1316 if (!kmap->ref_reloc_sym || !kmap->ref_reloc_sym->name) 1317 return 0; 1318 1319 if (kallsyms__get_function_start(filename, kmap->ref_reloc_sym->name, &addr)) 1320 return -1; 1321 1322 *delta = addr - kmap->ref_reloc_sym->addr; 1323 return 0; 1324 } 1325 1326 int __dso__load_kallsyms(struct dso *dso, const char *filename, 1327 struct map *map, bool no_kcore) 1328 { 1329 struct kmap *kmap = map__kmap(map); 1330 u64 delta = 0; 1331 1332 if (symbol__restricted_filename(filename, "/proc/kallsyms")) 1333 return -1; 1334 1335 if (!kmap || !kmap->kmaps) 1336 return -1; 1337 1338 if (dso__load_all_kallsyms(dso, filename) < 0) 1339 return -1; 1340 1341 if (kallsyms__delta(kmap, filename, &delta)) 1342 return -1; 1343 1344 symbols__fixup_end(&dso->symbols); 1345 symbols__fixup_duplicate(&dso->symbols); 1346 1347 if (dso->kernel == DSO_TYPE_GUEST_KERNEL) 1348 dso->symtab_type = DSO_BINARY_TYPE__GUEST_KALLSYMS; 1349 else 1350 dso->symtab_type = DSO_BINARY_TYPE__KALLSYMS; 1351 1352 if (!no_kcore && !dso__load_kcore(dso, map, filename)) 1353 return map_groups__split_kallsyms_for_kcore(kmap->kmaps, dso); 1354 else 1355 return map_groups__split_kallsyms(kmap->kmaps, dso, delta, map); 1356 } 1357 1358 int dso__load_kallsyms(struct dso *dso, const char *filename, 1359 struct map *map) 1360 { 1361 return __dso__load_kallsyms(dso, filename, map, false); 1362 } 1363 1364 static int dso__load_perf_map(const char *map_path, struct dso *dso) 1365 { 1366 char *line = NULL; 1367 size_t n; 1368 FILE *file; 1369 int nr_syms = 0; 1370 1371 file = fopen(map_path, "r"); 1372 if (file == NULL) 1373 goto out_failure; 1374 1375 while (!feof(file)) { 1376 u64 start, size; 1377 struct symbol *sym; 1378 int line_len, len; 1379 1380 line_len = getline(&line, &n, file); 1381 if (line_len < 0) 1382 break; 1383 1384 if (!line) 1385 goto out_failure; 1386 1387 line[--line_len] = '\0'; /* \n */ 1388 1389 len = hex2u64(line, &start); 1390 1391 len++; 1392 if (len + 2 >= line_len) 1393 continue; 1394 1395 len += hex2u64(line + len, &size); 1396 1397 len++; 1398 if (len + 2 >= line_len) 1399 continue; 1400 1401 sym = symbol__new(start, size, STB_GLOBAL, STT_FUNC, line + len); 1402 1403 if (sym == NULL) 1404 goto out_delete_line; 1405 1406 symbols__insert(&dso->symbols, sym); 1407 nr_syms++; 1408 } 1409 1410 free(line); 1411 fclose(file); 1412 1413 return nr_syms; 1414 1415 out_delete_line: 1416 free(line); 1417 out_failure: 1418 return -1; 1419 } 1420 1421 static bool dso__is_compatible_symtab_type(struct dso *dso, bool kmod, 1422 enum dso_binary_type type) 1423 { 1424 switch (type) { 1425 case DSO_BINARY_TYPE__JAVA_JIT: 1426 case DSO_BINARY_TYPE__DEBUGLINK: 1427 case DSO_BINARY_TYPE__SYSTEM_PATH_DSO: 1428 case DSO_BINARY_TYPE__FEDORA_DEBUGINFO: 1429 case DSO_BINARY_TYPE__UBUNTU_DEBUGINFO: 1430 case DSO_BINARY_TYPE__BUILDID_DEBUGINFO: 1431 case DSO_BINARY_TYPE__OPENEMBEDDED_DEBUGINFO: 1432 return !kmod && dso->kernel == DSO_TYPE_USER; 1433 1434 case DSO_BINARY_TYPE__KALLSYMS: 1435 case DSO_BINARY_TYPE__VMLINUX: 1436 case DSO_BINARY_TYPE__KCORE: 1437 return dso->kernel == DSO_TYPE_KERNEL; 1438 1439 case DSO_BINARY_TYPE__GUEST_KALLSYMS: 1440 case DSO_BINARY_TYPE__GUEST_VMLINUX: 1441 case DSO_BINARY_TYPE__GUEST_KCORE: 1442 return dso->kernel == DSO_TYPE_GUEST_KERNEL; 1443 1444 case DSO_BINARY_TYPE__GUEST_KMODULE: 1445 case DSO_BINARY_TYPE__GUEST_KMODULE_COMP: 1446 case DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE: 1447 case DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP: 1448 /* 1449 * kernel modules know their symtab type - it's set when 1450 * creating a module dso in machine__findnew_module_map(). 1451 */ 1452 return kmod && dso->symtab_type == type; 1453 1454 case DSO_BINARY_TYPE__BUILD_ID_CACHE: 1455 case DSO_BINARY_TYPE__BUILD_ID_CACHE_DEBUGINFO: 1456 return true; 1457 1458 case DSO_BINARY_TYPE__BPF_PROG_INFO: 1459 case DSO_BINARY_TYPE__NOT_FOUND: 1460 default: 1461 return false; 1462 } 1463 } 1464 1465 /* Checks for the existence of the perf-<pid>.map file in two different 1466 * locations. First, if the process is a separate mount namespace, check in 1467 * that namespace using the pid of the innermost pid namespace. If's not in a 1468 * namespace, or the file can't be found there, try in the mount namespace of 1469 * the tracing process using our view of its pid. 1470 */ 1471 static int dso__find_perf_map(char *filebuf, size_t bufsz, 1472 struct nsinfo **nsip) 1473 { 1474 struct nscookie nsc; 1475 struct nsinfo *nsi; 1476 struct nsinfo *nnsi; 1477 int rc = -1; 1478 1479 nsi = *nsip; 1480 1481 if (nsi->need_setns) { 1482 snprintf(filebuf, bufsz, "/tmp/perf-%d.map", nsi->nstgid); 1483 nsinfo__mountns_enter(nsi, &nsc); 1484 rc = access(filebuf, R_OK); 1485 nsinfo__mountns_exit(&nsc); 1486 if (rc == 0) 1487 return rc; 1488 } 1489 1490 nnsi = nsinfo__copy(nsi); 1491 if (nnsi) { 1492 nsinfo__put(nsi); 1493 1494 nnsi->need_setns = false; 1495 snprintf(filebuf, bufsz, "/tmp/perf-%d.map", nnsi->tgid); 1496 *nsip = nnsi; 1497 rc = 0; 1498 } 1499 1500 return rc; 1501 } 1502 1503 int dso__load(struct dso *dso, struct map *map) 1504 { 1505 char *name; 1506 int ret = -1; 1507 u_int i; 1508 struct machine *machine; 1509 char *root_dir = (char *) ""; 1510 int ss_pos = 0; 1511 struct symsrc ss_[2]; 1512 struct symsrc *syms_ss = NULL, *runtime_ss = NULL; 1513 bool kmod; 1514 bool perfmap; 1515 unsigned char build_id[BUILD_ID_SIZE]; 1516 struct nscookie nsc; 1517 char newmapname[PATH_MAX]; 1518 const char *map_path = dso->long_name; 1519 1520 perfmap = strncmp(dso->name, "/tmp/perf-", 10) == 0; 1521 if (perfmap) { 1522 if (dso->nsinfo && (dso__find_perf_map(newmapname, 1523 sizeof(newmapname), &dso->nsinfo) == 0)) { 1524 map_path = newmapname; 1525 } 1526 } 1527 1528 nsinfo__mountns_enter(dso->nsinfo, &nsc); 1529 pthread_mutex_lock(&dso->lock); 1530 1531 /* check again under the dso->lock */ 1532 if (dso__loaded(dso)) { 1533 ret = 1; 1534 goto out; 1535 } 1536 1537 if (map->groups && map->groups->machine) 1538 machine = map->groups->machine; 1539 else 1540 machine = NULL; 1541 1542 if (dso->kernel) { 1543 if (dso->kernel == DSO_TYPE_KERNEL) 1544 ret = dso__load_kernel_sym(dso, map); 1545 else if (dso->kernel == DSO_TYPE_GUEST_KERNEL) 1546 ret = dso__load_guest_kernel_sym(dso, map); 1547 1548 if (machine__is(machine, "x86_64")) 1549 machine__map_x86_64_entry_trampolines(machine, dso); 1550 goto out; 1551 } 1552 1553 dso->adjust_symbols = 0; 1554 1555 if (perfmap) { 1556 ret = dso__load_perf_map(map_path, dso); 1557 dso->symtab_type = ret > 0 ? DSO_BINARY_TYPE__JAVA_JIT : 1558 DSO_BINARY_TYPE__NOT_FOUND; 1559 goto out; 1560 } 1561 1562 if (machine) 1563 root_dir = machine->root_dir; 1564 1565 name = malloc(PATH_MAX); 1566 if (!name) 1567 goto out; 1568 1569 kmod = dso->symtab_type == DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE || 1570 dso->symtab_type == DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP || 1571 dso->symtab_type == DSO_BINARY_TYPE__GUEST_KMODULE || 1572 dso->symtab_type == DSO_BINARY_TYPE__GUEST_KMODULE_COMP; 1573 1574 1575 /* 1576 * Read the build id if possible. This is required for 1577 * DSO_BINARY_TYPE__BUILDID_DEBUGINFO to work 1578 */ 1579 if (!dso->has_build_id && 1580 is_regular_file(dso->long_name)) { 1581 __symbol__join_symfs(name, PATH_MAX, dso->long_name); 1582 if (filename__read_build_id(name, build_id, BUILD_ID_SIZE) > 0) 1583 dso__set_build_id(dso, build_id); 1584 } 1585 1586 /* 1587 * Iterate over candidate debug images. 1588 * Keep track of "interesting" ones (those which have a symtab, dynsym, 1589 * and/or opd section) for processing. 1590 */ 1591 for (i = 0; i < DSO_BINARY_TYPE__SYMTAB_CNT; i++) { 1592 struct symsrc *ss = &ss_[ss_pos]; 1593 bool next_slot = false; 1594 bool is_reg; 1595 bool nsexit; 1596 int sirc = -1; 1597 1598 enum dso_binary_type symtab_type = binary_type_symtab[i]; 1599 1600 nsexit = (symtab_type == DSO_BINARY_TYPE__BUILD_ID_CACHE || 1601 symtab_type == DSO_BINARY_TYPE__BUILD_ID_CACHE_DEBUGINFO); 1602 1603 if (!dso__is_compatible_symtab_type(dso, kmod, symtab_type)) 1604 continue; 1605 1606 if (dso__read_binary_type_filename(dso, symtab_type, 1607 root_dir, name, PATH_MAX)) 1608 continue; 1609 1610 if (nsexit) 1611 nsinfo__mountns_exit(&nsc); 1612 1613 is_reg = is_regular_file(name); 1614 if (is_reg) 1615 sirc = symsrc__init(ss, dso, name, symtab_type); 1616 1617 if (nsexit) 1618 nsinfo__mountns_enter(dso->nsinfo, &nsc); 1619 1620 if (!is_reg || sirc < 0) 1621 continue; 1622 1623 if (!syms_ss && symsrc__has_symtab(ss)) { 1624 syms_ss = ss; 1625 next_slot = true; 1626 if (!dso->symsrc_filename) 1627 dso->symsrc_filename = strdup(name); 1628 } 1629 1630 if (!runtime_ss && symsrc__possibly_runtime(ss)) { 1631 runtime_ss = ss; 1632 next_slot = true; 1633 } 1634 1635 if (next_slot) { 1636 ss_pos++; 1637 1638 if (syms_ss && runtime_ss) 1639 break; 1640 } else { 1641 symsrc__destroy(ss); 1642 } 1643 1644 } 1645 1646 if (!runtime_ss && !syms_ss) 1647 goto out_free; 1648 1649 if (runtime_ss && !syms_ss) { 1650 syms_ss = runtime_ss; 1651 } 1652 1653 /* We'll have to hope for the best */ 1654 if (!runtime_ss && syms_ss) 1655 runtime_ss = syms_ss; 1656 1657 if (syms_ss) 1658 ret = dso__load_sym(dso, map, syms_ss, runtime_ss, kmod); 1659 else 1660 ret = -1; 1661 1662 if (ret > 0) { 1663 int nr_plt; 1664 1665 nr_plt = dso__synthesize_plt_symbols(dso, runtime_ss); 1666 if (nr_plt > 0) 1667 ret += nr_plt; 1668 } 1669 1670 for (; ss_pos > 0; ss_pos--) 1671 symsrc__destroy(&ss_[ss_pos - 1]); 1672 out_free: 1673 free(name); 1674 if (ret < 0 && strstr(dso->name, " (deleted)") != NULL) 1675 ret = 0; 1676 out: 1677 dso__set_loaded(dso); 1678 pthread_mutex_unlock(&dso->lock); 1679 nsinfo__mountns_exit(&nsc); 1680 1681 return ret; 1682 } 1683 1684 struct map *map_groups__find_by_name(struct map_groups *mg, const char *name) 1685 { 1686 struct maps *maps = &mg->maps; 1687 struct map *map; 1688 struct rb_node *node; 1689 1690 down_read(&maps->lock); 1691 1692 for (node = maps->names.rb_node; node; ) { 1693 int rc; 1694 1695 map = rb_entry(node, struct map, rb_node_name); 1696 1697 rc = strcmp(map->dso->short_name, name); 1698 if (rc < 0) 1699 node = node->rb_left; 1700 else if (rc > 0) 1701 node = node->rb_right; 1702 else 1703 1704 goto out_unlock; 1705 } 1706 1707 map = NULL; 1708 1709 out_unlock: 1710 up_read(&maps->lock); 1711 return map; 1712 } 1713 1714 int dso__load_vmlinux(struct dso *dso, struct map *map, 1715 const char *vmlinux, bool vmlinux_allocated) 1716 { 1717 int err = -1; 1718 struct symsrc ss; 1719 char symfs_vmlinux[PATH_MAX]; 1720 enum dso_binary_type symtab_type; 1721 1722 if (vmlinux[0] == '/') 1723 snprintf(symfs_vmlinux, sizeof(symfs_vmlinux), "%s", vmlinux); 1724 else 1725 symbol__join_symfs(symfs_vmlinux, vmlinux); 1726 1727 if (dso->kernel == DSO_TYPE_GUEST_KERNEL) 1728 symtab_type = DSO_BINARY_TYPE__GUEST_VMLINUX; 1729 else 1730 symtab_type = DSO_BINARY_TYPE__VMLINUX; 1731 1732 if (symsrc__init(&ss, dso, symfs_vmlinux, symtab_type)) 1733 return -1; 1734 1735 err = dso__load_sym(dso, map, &ss, &ss, 0); 1736 symsrc__destroy(&ss); 1737 1738 if (err > 0) { 1739 if (dso->kernel == DSO_TYPE_GUEST_KERNEL) 1740 dso->binary_type = DSO_BINARY_TYPE__GUEST_VMLINUX; 1741 else 1742 dso->binary_type = DSO_BINARY_TYPE__VMLINUX; 1743 dso__set_long_name(dso, vmlinux, vmlinux_allocated); 1744 dso__set_loaded(dso); 1745 pr_debug("Using %s for symbols\n", symfs_vmlinux); 1746 } 1747 1748 return err; 1749 } 1750 1751 int dso__load_vmlinux_path(struct dso *dso, struct map *map) 1752 { 1753 int i, err = 0; 1754 char *filename = NULL; 1755 1756 pr_debug("Looking at the vmlinux_path (%d entries long)\n", 1757 vmlinux_path__nr_entries + 1); 1758 1759 for (i = 0; i < vmlinux_path__nr_entries; ++i) { 1760 err = dso__load_vmlinux(dso, map, vmlinux_path[i], false); 1761 if (err > 0) 1762 goto out; 1763 } 1764 1765 if (!symbol_conf.ignore_vmlinux_buildid) 1766 filename = dso__build_id_filename(dso, NULL, 0, false); 1767 if (filename != NULL) { 1768 err = dso__load_vmlinux(dso, map, filename, true); 1769 if (err > 0) 1770 goto out; 1771 free(filename); 1772 } 1773 out: 1774 return err; 1775 } 1776 1777 static bool visible_dir_filter(const char *name, struct dirent *d) 1778 { 1779 if (d->d_type != DT_DIR) 1780 return false; 1781 return lsdir_no_dot_filter(name, d); 1782 } 1783 1784 static int find_matching_kcore(struct map *map, char *dir, size_t dir_sz) 1785 { 1786 char kallsyms_filename[PATH_MAX]; 1787 int ret = -1; 1788 struct strlist *dirs; 1789 struct str_node *nd; 1790 1791 dirs = lsdir(dir, visible_dir_filter); 1792 if (!dirs) 1793 return -1; 1794 1795 strlist__for_each_entry(nd, dirs) { 1796 scnprintf(kallsyms_filename, sizeof(kallsyms_filename), 1797 "%s/%s/kallsyms", dir, nd->s); 1798 if (!validate_kcore_addresses(kallsyms_filename, map)) { 1799 strlcpy(dir, kallsyms_filename, dir_sz); 1800 ret = 0; 1801 break; 1802 } 1803 } 1804 1805 strlist__delete(dirs); 1806 1807 return ret; 1808 } 1809 1810 /* 1811 * Use open(O_RDONLY) to check readability directly instead of access(R_OK) 1812 * since access(R_OK) only checks with real UID/GID but open() use effective 1813 * UID/GID and actual capabilities (e.g. /proc/kcore requires CAP_SYS_RAWIO). 1814 */ 1815 static bool filename__readable(const char *file) 1816 { 1817 int fd = open(file, O_RDONLY); 1818 if (fd < 0) 1819 return false; 1820 close(fd); 1821 return true; 1822 } 1823 1824 static char *dso__find_kallsyms(struct dso *dso, struct map *map) 1825 { 1826 u8 host_build_id[BUILD_ID_SIZE]; 1827 char sbuild_id[SBUILD_ID_SIZE]; 1828 bool is_host = false; 1829 char path[PATH_MAX]; 1830 1831 if (!dso->has_build_id) { 1832 /* 1833 * Last resort, if we don't have a build-id and couldn't find 1834 * any vmlinux file, try the running kernel kallsyms table. 1835 */ 1836 goto proc_kallsyms; 1837 } 1838 1839 if (sysfs__read_build_id("/sys/kernel/notes", host_build_id, 1840 sizeof(host_build_id)) == 0) 1841 is_host = dso__build_id_equal(dso, host_build_id); 1842 1843 /* Try a fast path for /proc/kallsyms if possible */ 1844 if (is_host) { 1845 /* 1846 * Do not check the build-id cache, unless we know we cannot use 1847 * /proc/kcore or module maps don't match to /proc/kallsyms. 1848 * To check readability of /proc/kcore, do not use access(R_OK) 1849 * since /proc/kcore requires CAP_SYS_RAWIO to read and access 1850 * can't check it. 1851 */ 1852 if (filename__readable("/proc/kcore") && 1853 !validate_kcore_addresses("/proc/kallsyms", map)) 1854 goto proc_kallsyms; 1855 } 1856 1857 build_id__sprintf(dso->build_id, sizeof(dso->build_id), sbuild_id); 1858 1859 /* Find kallsyms in build-id cache with kcore */ 1860 scnprintf(path, sizeof(path), "%s/%s/%s", 1861 buildid_dir, DSO__NAME_KCORE, sbuild_id); 1862 1863 if (!find_matching_kcore(map, path, sizeof(path))) 1864 return strdup(path); 1865 1866 /* Use current /proc/kallsyms if possible */ 1867 if (is_host) { 1868 proc_kallsyms: 1869 return strdup("/proc/kallsyms"); 1870 } 1871 1872 /* Finally, find a cache of kallsyms */ 1873 if (!build_id_cache__kallsyms_path(sbuild_id, path, sizeof(path))) { 1874 pr_err("No kallsyms or vmlinux with build-id %s was found\n", 1875 sbuild_id); 1876 return NULL; 1877 } 1878 1879 return strdup(path); 1880 } 1881 1882 static int dso__load_kernel_sym(struct dso *dso, struct map *map) 1883 { 1884 int err; 1885 const char *kallsyms_filename = NULL; 1886 char *kallsyms_allocated_filename = NULL; 1887 /* 1888 * Step 1: if the user specified a kallsyms or vmlinux filename, use 1889 * it and only it, reporting errors to the user if it cannot be used. 1890 * 1891 * For instance, try to analyse an ARM perf.data file _without_ a 1892 * build-id, or if the user specifies the wrong path to the right 1893 * vmlinux file, obviously we can't fallback to another vmlinux (a 1894 * x86_86 one, on the machine where analysis is being performed, say), 1895 * or worse, /proc/kallsyms. 1896 * 1897 * If the specified file _has_ a build-id and there is a build-id 1898 * section in the perf.data file, we will still do the expected 1899 * validation in dso__load_vmlinux and will bail out if they don't 1900 * match. 1901 */ 1902 if (symbol_conf.kallsyms_name != NULL) { 1903 kallsyms_filename = symbol_conf.kallsyms_name; 1904 goto do_kallsyms; 1905 } 1906 1907 if (!symbol_conf.ignore_vmlinux && symbol_conf.vmlinux_name != NULL) { 1908 return dso__load_vmlinux(dso, map, symbol_conf.vmlinux_name, false); 1909 } 1910 1911 if (!symbol_conf.ignore_vmlinux && vmlinux_path != NULL) { 1912 err = dso__load_vmlinux_path(dso, map); 1913 if (err > 0) 1914 return err; 1915 } 1916 1917 /* do not try local files if a symfs was given */ 1918 if (symbol_conf.symfs[0] != 0) 1919 return -1; 1920 1921 kallsyms_allocated_filename = dso__find_kallsyms(dso, map); 1922 if (!kallsyms_allocated_filename) 1923 return -1; 1924 1925 kallsyms_filename = kallsyms_allocated_filename; 1926 1927 do_kallsyms: 1928 err = dso__load_kallsyms(dso, kallsyms_filename, map); 1929 if (err > 0) 1930 pr_debug("Using %s for symbols\n", kallsyms_filename); 1931 free(kallsyms_allocated_filename); 1932 1933 if (err > 0 && !dso__is_kcore(dso)) { 1934 dso->binary_type = DSO_BINARY_TYPE__KALLSYMS; 1935 dso__set_long_name(dso, DSO__NAME_KALLSYMS, false); 1936 map__fixup_start(map); 1937 map__fixup_end(map); 1938 } 1939 1940 return err; 1941 } 1942 1943 static int dso__load_guest_kernel_sym(struct dso *dso, struct map *map) 1944 { 1945 int err; 1946 const char *kallsyms_filename = NULL; 1947 struct machine *machine; 1948 char path[PATH_MAX]; 1949 1950 if (!map->groups) { 1951 pr_debug("Guest kernel map hasn't the point to groups\n"); 1952 return -1; 1953 } 1954 machine = map->groups->machine; 1955 1956 if (machine__is_default_guest(machine)) { 1957 /* 1958 * if the user specified a vmlinux filename, use it and only 1959 * it, reporting errors to the user if it cannot be used. 1960 * Or use file guest_kallsyms inputted by user on commandline 1961 */ 1962 if (symbol_conf.default_guest_vmlinux_name != NULL) { 1963 err = dso__load_vmlinux(dso, map, 1964 symbol_conf.default_guest_vmlinux_name, 1965 false); 1966 return err; 1967 } 1968 1969 kallsyms_filename = symbol_conf.default_guest_kallsyms; 1970 if (!kallsyms_filename) 1971 return -1; 1972 } else { 1973 sprintf(path, "%s/proc/kallsyms", machine->root_dir); 1974 kallsyms_filename = path; 1975 } 1976 1977 err = dso__load_kallsyms(dso, kallsyms_filename, map); 1978 if (err > 0) 1979 pr_debug("Using %s for symbols\n", kallsyms_filename); 1980 if (err > 0 && !dso__is_kcore(dso)) { 1981 dso->binary_type = DSO_BINARY_TYPE__GUEST_KALLSYMS; 1982 dso__set_long_name(dso, machine->mmap_name, false); 1983 map__fixup_start(map); 1984 map__fixup_end(map); 1985 } 1986 1987 return err; 1988 } 1989 1990 static void vmlinux_path__exit(void) 1991 { 1992 while (--vmlinux_path__nr_entries >= 0) 1993 zfree(&vmlinux_path[vmlinux_path__nr_entries]); 1994 vmlinux_path__nr_entries = 0; 1995 1996 zfree(&vmlinux_path); 1997 } 1998 1999 static const char * const vmlinux_paths[] = { 2000 "vmlinux", 2001 "/boot/vmlinux" 2002 }; 2003 2004 static const char * const vmlinux_paths_upd[] = { 2005 "/boot/vmlinux-%s", 2006 "/usr/lib/debug/boot/vmlinux-%s", 2007 "/lib/modules/%s/build/vmlinux", 2008 "/usr/lib/debug/lib/modules/%s/vmlinux", 2009 "/usr/lib/debug/boot/vmlinux-%s.debug" 2010 }; 2011 2012 static int vmlinux_path__add(const char *new_entry) 2013 { 2014 vmlinux_path[vmlinux_path__nr_entries] = strdup(new_entry); 2015 if (vmlinux_path[vmlinux_path__nr_entries] == NULL) 2016 return -1; 2017 ++vmlinux_path__nr_entries; 2018 2019 return 0; 2020 } 2021 2022 static int vmlinux_path__init(struct perf_env *env) 2023 { 2024 struct utsname uts; 2025 char bf[PATH_MAX]; 2026 char *kernel_version; 2027 unsigned int i; 2028 2029 vmlinux_path = malloc(sizeof(char *) * (ARRAY_SIZE(vmlinux_paths) + 2030 ARRAY_SIZE(vmlinux_paths_upd))); 2031 if (vmlinux_path == NULL) 2032 return -1; 2033 2034 for (i = 0; i < ARRAY_SIZE(vmlinux_paths); i++) 2035 if (vmlinux_path__add(vmlinux_paths[i]) < 0) 2036 goto out_fail; 2037 2038 /* only try kernel version if no symfs was given */ 2039 if (symbol_conf.symfs[0] != 0) 2040 return 0; 2041 2042 if (env) { 2043 kernel_version = env->os_release; 2044 } else { 2045 if (uname(&uts) < 0) 2046 goto out_fail; 2047 2048 kernel_version = uts.release; 2049 } 2050 2051 for (i = 0; i < ARRAY_SIZE(vmlinux_paths_upd); i++) { 2052 snprintf(bf, sizeof(bf), vmlinux_paths_upd[i], kernel_version); 2053 if (vmlinux_path__add(bf) < 0) 2054 goto out_fail; 2055 } 2056 2057 return 0; 2058 2059 out_fail: 2060 vmlinux_path__exit(); 2061 return -1; 2062 } 2063 2064 int setup_list(struct strlist **list, const char *list_str, 2065 const char *list_name) 2066 { 2067 if (list_str == NULL) 2068 return 0; 2069 2070 *list = strlist__new(list_str, NULL); 2071 if (!*list) { 2072 pr_err("problems parsing %s list\n", list_name); 2073 return -1; 2074 } 2075 2076 symbol_conf.has_filter = true; 2077 return 0; 2078 } 2079 2080 int setup_intlist(struct intlist **list, const char *list_str, 2081 const char *list_name) 2082 { 2083 if (list_str == NULL) 2084 return 0; 2085 2086 *list = intlist__new(list_str); 2087 if (!*list) { 2088 pr_err("problems parsing %s list\n", list_name); 2089 return -1; 2090 } 2091 return 0; 2092 } 2093 2094 static bool symbol__read_kptr_restrict(void) 2095 { 2096 bool value = false; 2097 FILE *fp = fopen("/proc/sys/kernel/kptr_restrict", "r"); 2098 2099 if (fp != NULL) { 2100 char line[8]; 2101 2102 if (fgets(line, sizeof(line), fp) != NULL) 2103 value = ((geteuid() != 0) || (getuid() != 0)) ? 2104 (atoi(line) != 0) : 2105 (atoi(line) == 2); 2106 2107 fclose(fp); 2108 } 2109 2110 return value; 2111 } 2112 2113 int symbol__annotation_init(void) 2114 { 2115 if (symbol_conf.init_annotation) 2116 return 0; 2117 2118 if (symbol_conf.initialized) { 2119 pr_err("Annotation needs to be init before symbol__init()\n"); 2120 return -1; 2121 } 2122 2123 symbol_conf.priv_size += sizeof(struct annotation); 2124 symbol_conf.init_annotation = true; 2125 return 0; 2126 } 2127 2128 int symbol__init(struct perf_env *env) 2129 { 2130 const char *symfs; 2131 2132 if (symbol_conf.initialized) 2133 return 0; 2134 2135 symbol_conf.priv_size = PERF_ALIGN(symbol_conf.priv_size, sizeof(u64)); 2136 2137 symbol__elf_init(); 2138 2139 if (symbol_conf.sort_by_name) 2140 symbol_conf.priv_size += (sizeof(struct symbol_name_rb_node) - 2141 sizeof(struct symbol)); 2142 2143 if (symbol_conf.try_vmlinux_path && vmlinux_path__init(env) < 0) 2144 return -1; 2145 2146 if (symbol_conf.field_sep && *symbol_conf.field_sep == '.') { 2147 pr_err("'.' is the only non valid --field-separator argument\n"); 2148 return -1; 2149 } 2150 2151 if (setup_list(&symbol_conf.dso_list, 2152 symbol_conf.dso_list_str, "dso") < 0) 2153 return -1; 2154 2155 if (setup_list(&symbol_conf.comm_list, 2156 symbol_conf.comm_list_str, "comm") < 0) 2157 goto out_free_dso_list; 2158 2159 if (setup_intlist(&symbol_conf.pid_list, 2160 symbol_conf.pid_list_str, "pid") < 0) 2161 goto out_free_comm_list; 2162 2163 if (setup_intlist(&symbol_conf.tid_list, 2164 symbol_conf.tid_list_str, "tid") < 0) 2165 goto out_free_pid_list; 2166 2167 if (setup_list(&symbol_conf.sym_list, 2168 symbol_conf.sym_list_str, "symbol") < 0) 2169 goto out_free_tid_list; 2170 2171 if (setup_list(&symbol_conf.bt_stop_list, 2172 symbol_conf.bt_stop_list_str, "symbol") < 0) 2173 goto out_free_sym_list; 2174 2175 /* 2176 * A path to symbols of "/" is identical to "" 2177 * reset here for simplicity. 2178 */ 2179 symfs = realpath(symbol_conf.symfs, NULL); 2180 if (symfs == NULL) 2181 symfs = symbol_conf.symfs; 2182 if (strcmp(symfs, "/") == 0) 2183 symbol_conf.symfs = ""; 2184 if (symfs != symbol_conf.symfs) 2185 free((void *)symfs); 2186 2187 symbol_conf.kptr_restrict = symbol__read_kptr_restrict(); 2188 2189 symbol_conf.initialized = true; 2190 return 0; 2191 2192 out_free_sym_list: 2193 strlist__delete(symbol_conf.sym_list); 2194 out_free_tid_list: 2195 intlist__delete(symbol_conf.tid_list); 2196 out_free_pid_list: 2197 intlist__delete(symbol_conf.pid_list); 2198 out_free_comm_list: 2199 strlist__delete(symbol_conf.comm_list); 2200 out_free_dso_list: 2201 strlist__delete(symbol_conf.dso_list); 2202 return -1; 2203 } 2204 2205 void symbol__exit(void) 2206 { 2207 if (!symbol_conf.initialized) 2208 return; 2209 strlist__delete(symbol_conf.bt_stop_list); 2210 strlist__delete(symbol_conf.sym_list); 2211 strlist__delete(symbol_conf.dso_list); 2212 strlist__delete(symbol_conf.comm_list); 2213 intlist__delete(symbol_conf.tid_list); 2214 intlist__delete(symbol_conf.pid_list); 2215 vmlinux_path__exit(); 2216 symbol_conf.sym_list = symbol_conf.dso_list = symbol_conf.comm_list = NULL; 2217 symbol_conf.bt_stop_list = NULL; 2218 symbol_conf.initialized = false; 2219 } 2220 2221 int symbol__config_symfs(const struct option *opt __maybe_unused, 2222 const char *dir, int unset __maybe_unused) 2223 { 2224 char *bf = NULL; 2225 int ret; 2226 2227 symbol_conf.symfs = strdup(dir); 2228 if (symbol_conf.symfs == NULL) 2229 return -ENOMEM; 2230 2231 /* skip the locally configured cache if a symfs is given, and 2232 * config buildid dir to symfs/.debug 2233 */ 2234 ret = asprintf(&bf, "%s/%s", dir, ".debug"); 2235 if (ret < 0) 2236 return -ENOMEM; 2237 2238 set_buildid_dir(bf); 2239 2240 free(bf); 2241 return 0; 2242 } 2243 2244 struct mem_info *mem_info__get(struct mem_info *mi) 2245 { 2246 if (mi) 2247 refcount_inc(&mi->refcnt); 2248 return mi; 2249 } 2250 2251 void mem_info__put(struct mem_info *mi) 2252 { 2253 if (mi && refcount_dec_and_test(&mi->refcnt)) 2254 free(mi); 2255 } 2256 2257 struct mem_info *mem_info__new(void) 2258 { 2259 struct mem_info *mi = zalloc(sizeof(*mi)); 2260 2261 if (mi) 2262 refcount_set(&mi->refcnt, 1); 2263 return mi; 2264 } 2265