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/capability.h> 8 #include <linux/kernel.h> 9 #include <linux/mman.h> 10 #include <linux/string.h> 11 #include <linux/time64.h> 12 #include <sys/types.h> 13 #include <sys/stat.h> 14 #include <sys/param.h> 15 #include <fcntl.h> 16 #include <unistd.h> 17 #include <inttypes.h> 18 #include "annotate.h" 19 #include "build-id.h" 20 #include "cap.h" 21 #include "dso.h" 22 #include "util.h" // lsdir() 23 #include "debug.h" 24 #include "event.h" 25 #include "machine.h" 26 #include "map.h" 27 #include "symbol.h" 28 #include "map_symbol.h" 29 #include "mem-events.h" 30 #include "symsrc.h" 31 #include "strlist.h" 32 #include "intlist.h" 33 #include "namespaces.h" 34 #include "header.h" 35 #include "path.h" 36 #include <linux/ctype.h> 37 #include <linux/zalloc.h> 38 39 #include <elf.h> 40 #include <limits.h> 41 #include <symbol/kallsyms.h> 42 #include <sys/utsname.h> 43 44 static int dso__load_kernel_sym(struct dso *dso, struct map *map); 45 static int dso__load_guest_kernel_sym(struct dso *dso, struct map *map); 46 static bool symbol__is_idle(const char *name); 47 48 int vmlinux_path__nr_entries; 49 char **vmlinux_path; 50 51 struct map_list_node { 52 struct list_head node; 53 struct map *map; 54 }; 55 56 struct symbol_conf symbol_conf = { 57 .nanosecs = false, 58 .use_modules = true, 59 .try_vmlinux_path = true, 60 .demangle = true, 61 .demangle_kernel = false, 62 .cumulate_callchain = true, 63 .time_quantum = 100 * NSEC_PER_MSEC, /* 100ms */ 64 .show_hist_headers = true, 65 .symfs = "", 66 .event_group = true, 67 .inline_name = true, 68 .res_sample = 0, 69 }; 70 71 static enum dso_binary_type binary_type_symtab[] = { 72 DSO_BINARY_TYPE__KALLSYMS, 73 DSO_BINARY_TYPE__GUEST_KALLSYMS, 74 DSO_BINARY_TYPE__JAVA_JIT, 75 DSO_BINARY_TYPE__DEBUGLINK, 76 DSO_BINARY_TYPE__BUILD_ID_CACHE, 77 DSO_BINARY_TYPE__BUILD_ID_CACHE_DEBUGINFO, 78 DSO_BINARY_TYPE__FEDORA_DEBUGINFO, 79 DSO_BINARY_TYPE__UBUNTU_DEBUGINFO, 80 DSO_BINARY_TYPE__BUILDID_DEBUGINFO, 81 DSO_BINARY_TYPE__SYSTEM_PATH_DSO, 82 DSO_BINARY_TYPE__GUEST_KMODULE, 83 DSO_BINARY_TYPE__GUEST_KMODULE_COMP, 84 DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE, 85 DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP, 86 DSO_BINARY_TYPE__OPENEMBEDDED_DEBUGINFO, 87 DSO_BINARY_TYPE__MIXEDUP_UBUNTU_DEBUGINFO, 88 DSO_BINARY_TYPE__NOT_FOUND, 89 }; 90 91 #define DSO_BINARY_TYPE__SYMTAB_CNT ARRAY_SIZE(binary_type_symtab) 92 93 static struct map_list_node *map_list_node__new(void) 94 { 95 return malloc(sizeof(struct map_list_node)); 96 } 97 98 static bool symbol_type__filter(char symbol_type) 99 { 100 symbol_type = toupper(symbol_type); 101 return symbol_type == 'T' || symbol_type == 'W' || symbol_type == 'D' || symbol_type == 'B'; 102 } 103 104 static int prefix_underscores_count(const char *str) 105 { 106 const char *tail = str; 107 108 while (*tail == '_') 109 tail++; 110 111 return tail - str; 112 } 113 114 const char * __weak arch__normalize_symbol_name(const char *name) 115 { 116 return name; 117 } 118 119 int __weak arch__compare_symbol_names(const char *namea, const char *nameb) 120 { 121 return strcmp(namea, nameb); 122 } 123 124 int __weak arch__compare_symbol_names_n(const char *namea, const char *nameb, 125 unsigned int n) 126 { 127 return strncmp(namea, nameb, n); 128 } 129 130 int __weak arch__choose_best_symbol(struct symbol *syma, 131 struct symbol *symb __maybe_unused) 132 { 133 /* Avoid "SyS" kernel syscall aliases */ 134 if (strlen(syma->name) >= 3 && !strncmp(syma->name, "SyS", 3)) 135 return SYMBOL_B; 136 if (strlen(syma->name) >= 10 && !strncmp(syma->name, "compat_SyS", 10)) 137 return SYMBOL_B; 138 139 return SYMBOL_A; 140 } 141 142 static int choose_best_symbol(struct symbol *syma, struct symbol *symb) 143 { 144 s64 a; 145 s64 b; 146 size_t na, nb; 147 148 /* Prefer a symbol with non zero length */ 149 a = syma->end - syma->start; 150 b = symb->end - symb->start; 151 if ((b == 0) && (a > 0)) 152 return SYMBOL_A; 153 else if ((a == 0) && (b > 0)) 154 return SYMBOL_B; 155 156 /* Prefer a non weak symbol over a weak one */ 157 a = syma->binding == STB_WEAK; 158 b = symb->binding == STB_WEAK; 159 if (b && !a) 160 return SYMBOL_A; 161 if (a && !b) 162 return SYMBOL_B; 163 164 /* Prefer a global symbol over a non global one */ 165 a = syma->binding == STB_GLOBAL; 166 b = symb->binding == STB_GLOBAL; 167 if (a && !b) 168 return SYMBOL_A; 169 if (b && !a) 170 return SYMBOL_B; 171 172 /* Prefer a symbol with less underscores */ 173 a = prefix_underscores_count(syma->name); 174 b = prefix_underscores_count(symb->name); 175 if (b > a) 176 return SYMBOL_A; 177 else if (a > b) 178 return SYMBOL_B; 179 180 /* Choose the symbol with the longest name */ 181 na = strlen(syma->name); 182 nb = strlen(symb->name); 183 if (na > nb) 184 return SYMBOL_A; 185 else if (na < nb) 186 return SYMBOL_B; 187 188 return arch__choose_best_symbol(syma, symb); 189 } 190 191 void symbols__fixup_duplicate(struct rb_root_cached *symbols) 192 { 193 struct rb_node *nd; 194 struct symbol *curr, *next; 195 196 if (symbol_conf.allow_aliases) 197 return; 198 199 nd = rb_first_cached(symbols); 200 201 while (nd) { 202 curr = rb_entry(nd, struct symbol, rb_node); 203 again: 204 nd = rb_next(&curr->rb_node); 205 if (!nd) 206 break; 207 208 next = rb_entry(nd, struct symbol, rb_node); 209 if (curr->start != next->start) 210 continue; 211 212 if (choose_best_symbol(curr, next) == SYMBOL_A) { 213 if (next->type == STT_GNU_IFUNC) 214 curr->ifunc_alias = true; 215 rb_erase_cached(&next->rb_node, symbols); 216 symbol__delete(next); 217 goto again; 218 } else { 219 if (curr->type == STT_GNU_IFUNC) 220 next->ifunc_alias = true; 221 nd = rb_next(&curr->rb_node); 222 rb_erase_cached(&curr->rb_node, symbols); 223 symbol__delete(curr); 224 } 225 } 226 } 227 228 /* Update zero-sized symbols using the address of the next symbol */ 229 void symbols__fixup_end(struct rb_root_cached *symbols, bool is_kallsyms) 230 { 231 struct rb_node *nd, *prevnd = rb_first_cached(symbols); 232 struct symbol *curr, *prev; 233 234 if (prevnd == NULL) 235 return; 236 237 curr = rb_entry(prevnd, struct symbol, rb_node); 238 239 for (nd = rb_next(prevnd); nd; nd = rb_next(nd)) { 240 prev = curr; 241 curr = rb_entry(nd, struct symbol, rb_node); 242 243 /* 244 * On some architecture kernel text segment start is located at 245 * some low memory address, while modules are located at high 246 * memory addresses (or vice versa). The gap between end of 247 * kernel text segment and beginning of first module's text 248 * segment is very big. Therefore do not fill this gap and do 249 * not assign it to the kernel dso map (kallsyms). 250 * 251 * In kallsyms, it determines module symbols using '[' character 252 * like in: 253 * ffffffffc1937000 T hdmi_driver_init [snd_hda_codec_hdmi] 254 */ 255 if (prev->end == prev->start) { 256 /* Last kernel/module symbol mapped to end of page */ 257 if (is_kallsyms && (!strchr(prev->name, '[') != 258 !strchr(curr->name, '['))) 259 prev->end = roundup(prev->end + 4096, 4096); 260 else 261 prev->end = curr->start; 262 263 pr_debug4("%s sym:%s end:%#" PRIx64 "\n", 264 __func__, prev->name, prev->end); 265 } 266 } 267 268 /* Last entry */ 269 if (curr->end == curr->start) 270 curr->end = roundup(curr->start, 4096) + 4096; 271 } 272 273 void maps__fixup_end(struct maps *maps) 274 { 275 struct map_rb_node *prev = NULL, *curr; 276 277 down_write(maps__lock(maps)); 278 279 maps__for_each_entry(maps, curr) { 280 if (prev != NULL && !map__end(prev->map)) 281 map__set_end(prev->map, map__start(curr->map)); 282 283 prev = curr; 284 } 285 286 /* 287 * We still haven't the actual symbols, so guess the 288 * last map final address. 289 */ 290 if (curr && !map__end(curr->map)) 291 map__set_end(curr->map, ~0ULL); 292 293 up_write(maps__lock(maps)); 294 } 295 296 struct symbol *symbol__new(u64 start, u64 len, u8 binding, u8 type, const char *name) 297 { 298 size_t namelen = strlen(name) + 1; 299 struct symbol *sym = calloc(1, (symbol_conf.priv_size + 300 sizeof(*sym) + namelen)); 301 if (sym == NULL) 302 return NULL; 303 304 if (symbol_conf.priv_size) { 305 if (symbol_conf.init_annotation) { 306 struct annotation *notes = (void *)sym; 307 annotation__init(notes); 308 } 309 sym = ((void *)sym) + symbol_conf.priv_size; 310 } 311 312 sym->start = start; 313 sym->end = len ? start + len : start; 314 sym->type = type; 315 sym->binding = binding; 316 sym->namelen = namelen - 1; 317 318 pr_debug4("%s: %s %#" PRIx64 "-%#" PRIx64 "\n", 319 __func__, name, start, sym->end); 320 memcpy(sym->name, name, namelen); 321 322 return sym; 323 } 324 325 void symbol__delete(struct symbol *sym) 326 { 327 if (symbol_conf.priv_size) { 328 if (symbol_conf.init_annotation) { 329 struct annotation *notes = symbol__annotation(sym); 330 331 annotation__exit(notes); 332 } 333 } 334 free(((void *)sym) - symbol_conf.priv_size); 335 } 336 337 void symbols__delete(struct rb_root_cached *symbols) 338 { 339 struct symbol *pos; 340 struct rb_node *next = rb_first_cached(symbols); 341 342 while (next) { 343 pos = rb_entry(next, struct symbol, rb_node); 344 next = rb_next(&pos->rb_node); 345 rb_erase_cached(&pos->rb_node, symbols); 346 symbol__delete(pos); 347 } 348 } 349 350 void __symbols__insert(struct rb_root_cached *symbols, 351 struct symbol *sym, bool kernel) 352 { 353 struct rb_node **p = &symbols->rb_root.rb_node; 354 struct rb_node *parent = NULL; 355 const u64 ip = sym->start; 356 struct symbol *s; 357 bool leftmost = true; 358 359 if (kernel) { 360 const char *name = sym->name; 361 /* 362 * ppc64 uses function descriptors and appends a '.' to the 363 * start of every instruction address. Remove it. 364 */ 365 if (name[0] == '.') 366 name++; 367 sym->idle = symbol__is_idle(name); 368 } 369 370 while (*p != NULL) { 371 parent = *p; 372 s = rb_entry(parent, struct symbol, rb_node); 373 if (ip < s->start) 374 p = &(*p)->rb_left; 375 else { 376 p = &(*p)->rb_right; 377 leftmost = false; 378 } 379 } 380 rb_link_node(&sym->rb_node, parent, p); 381 rb_insert_color_cached(&sym->rb_node, symbols, leftmost); 382 } 383 384 void symbols__insert(struct rb_root_cached *symbols, struct symbol *sym) 385 { 386 __symbols__insert(symbols, sym, false); 387 } 388 389 static struct symbol *symbols__find(struct rb_root_cached *symbols, u64 ip) 390 { 391 struct rb_node *n; 392 393 if (symbols == NULL) 394 return NULL; 395 396 n = symbols->rb_root.rb_node; 397 398 while (n) { 399 struct symbol *s = rb_entry(n, struct symbol, rb_node); 400 401 if (ip < s->start) 402 n = n->rb_left; 403 else if (ip > s->end || (ip == s->end && ip != s->start)) 404 n = n->rb_right; 405 else 406 return s; 407 } 408 409 return NULL; 410 } 411 412 static struct symbol *symbols__first(struct rb_root_cached *symbols) 413 { 414 struct rb_node *n = rb_first_cached(symbols); 415 416 if (n) 417 return rb_entry(n, struct symbol, rb_node); 418 419 return NULL; 420 } 421 422 static struct symbol *symbols__last(struct rb_root_cached *symbols) 423 { 424 struct rb_node *n = rb_last(&symbols->rb_root); 425 426 if (n) 427 return rb_entry(n, struct symbol, rb_node); 428 429 return NULL; 430 } 431 432 static struct symbol *symbols__next(struct symbol *sym) 433 { 434 struct rb_node *n = rb_next(&sym->rb_node); 435 436 if (n) 437 return rb_entry(n, struct symbol, rb_node); 438 439 return NULL; 440 } 441 442 static int symbols__sort_name_cmp(const void *vlhs, const void *vrhs) 443 { 444 const struct symbol *lhs = *((const struct symbol **)vlhs); 445 const struct symbol *rhs = *((const struct symbol **)vrhs); 446 447 return strcmp(lhs->name, rhs->name); 448 } 449 450 static struct symbol **symbols__sort_by_name(struct rb_root_cached *source, size_t *len) 451 { 452 struct rb_node *nd; 453 struct symbol **result; 454 size_t i = 0, size = 0; 455 456 for (nd = rb_first_cached(source); nd; nd = rb_next(nd)) 457 size++; 458 459 result = malloc(sizeof(*result) * size); 460 if (!result) 461 return NULL; 462 463 for (nd = rb_first_cached(source); nd; nd = rb_next(nd)) { 464 struct symbol *pos = rb_entry(nd, struct symbol, rb_node); 465 466 result[i++] = pos; 467 } 468 qsort(result, size, sizeof(*result), symbols__sort_name_cmp); 469 *len = size; 470 return result; 471 } 472 473 int symbol__match_symbol_name(const char *name, const char *str, 474 enum symbol_tag_include includes) 475 { 476 const char *versioning; 477 478 if (includes == SYMBOL_TAG_INCLUDE__DEFAULT_ONLY && 479 (versioning = strstr(name, "@@"))) { 480 int len = strlen(str); 481 482 if (len < versioning - name) 483 len = versioning - name; 484 485 return arch__compare_symbol_names_n(name, str, len); 486 } else 487 return arch__compare_symbol_names(name, str); 488 } 489 490 static struct symbol *symbols__find_by_name(struct symbol *symbols[], 491 size_t symbols_len, 492 const char *name, 493 enum symbol_tag_include includes, 494 size_t *found_idx) 495 { 496 size_t i, lower = 0, upper = symbols_len; 497 struct symbol *s = NULL; 498 499 if (found_idx) 500 *found_idx = SIZE_MAX; 501 502 if (!symbols_len) 503 return NULL; 504 505 while (lower < upper) { 506 int cmp; 507 508 i = (lower + upper) / 2; 509 cmp = symbol__match_symbol_name(symbols[i]->name, name, includes); 510 511 if (cmp > 0) 512 upper = i; 513 else if (cmp < 0) 514 lower = i + 1; 515 else { 516 if (found_idx) 517 *found_idx = i; 518 s = symbols[i]; 519 break; 520 } 521 } 522 if (s && includes != SYMBOL_TAG_INCLUDE__DEFAULT_ONLY) { 523 /* return first symbol that has same name (if any) */ 524 for (; i > 0; i--) { 525 struct symbol *tmp = symbols[i - 1]; 526 527 if (!arch__compare_symbol_names(tmp->name, s->name)) { 528 if (found_idx) 529 *found_idx = i - 1; 530 s = tmp; 531 } else 532 break; 533 } 534 } 535 assert(!found_idx || !s || s == symbols[*found_idx]); 536 return s; 537 } 538 539 void dso__reset_find_symbol_cache(struct dso *dso) 540 { 541 dso->last_find_result.addr = 0; 542 dso->last_find_result.symbol = NULL; 543 } 544 545 void dso__insert_symbol(struct dso *dso, struct symbol *sym) 546 { 547 __symbols__insert(&dso->symbols, sym, dso->kernel); 548 549 /* update the symbol cache if necessary */ 550 if (dso->last_find_result.addr >= sym->start && 551 (dso->last_find_result.addr < sym->end || 552 sym->start == sym->end)) { 553 dso->last_find_result.symbol = sym; 554 } 555 } 556 557 void dso__delete_symbol(struct dso *dso, struct symbol *sym) 558 { 559 rb_erase_cached(&sym->rb_node, &dso->symbols); 560 symbol__delete(sym); 561 dso__reset_find_symbol_cache(dso); 562 } 563 564 struct symbol *dso__find_symbol(struct dso *dso, u64 addr) 565 { 566 if (dso->last_find_result.addr != addr || dso->last_find_result.symbol == NULL) { 567 dso->last_find_result.addr = addr; 568 dso->last_find_result.symbol = symbols__find(&dso->symbols, addr); 569 } 570 571 return dso->last_find_result.symbol; 572 } 573 574 struct symbol *dso__find_symbol_nocache(struct dso *dso, u64 addr) 575 { 576 return symbols__find(&dso->symbols, addr); 577 } 578 579 struct symbol *dso__first_symbol(struct dso *dso) 580 { 581 return symbols__first(&dso->symbols); 582 } 583 584 struct symbol *dso__last_symbol(struct dso *dso) 585 { 586 return symbols__last(&dso->symbols); 587 } 588 589 struct symbol *dso__next_symbol(struct symbol *sym) 590 { 591 return symbols__next(sym); 592 } 593 594 struct symbol *dso__next_symbol_by_name(struct dso *dso, size_t *idx) 595 { 596 if (*idx + 1 >= dso->symbol_names_len) 597 return NULL; 598 599 ++*idx; 600 return dso->symbol_names[*idx]; 601 } 602 603 /* 604 * Returns first symbol that matched with @name. 605 */ 606 struct symbol *dso__find_symbol_by_name(struct dso *dso, const char *name, size_t *idx) 607 { 608 struct symbol *s = symbols__find_by_name(dso->symbol_names, dso->symbol_names_len, 609 name, SYMBOL_TAG_INCLUDE__NONE, idx); 610 if (!s) 611 s = symbols__find_by_name(dso->symbol_names, dso->symbol_names_len, 612 name, SYMBOL_TAG_INCLUDE__DEFAULT_ONLY, idx); 613 return s; 614 } 615 616 void dso__sort_by_name(struct dso *dso) 617 { 618 mutex_lock(&dso->lock); 619 if (!dso__sorted_by_name(dso)) { 620 size_t len; 621 622 dso->symbol_names = symbols__sort_by_name(&dso->symbols, &len); 623 if (dso->symbol_names) { 624 dso->symbol_names_len = len; 625 dso__set_sorted_by_name(dso); 626 } 627 } 628 mutex_unlock(&dso->lock); 629 } 630 631 /* 632 * While we find nice hex chars, build a long_val. 633 * Return number of chars processed. 634 */ 635 static int hex2u64(const char *ptr, u64 *long_val) 636 { 637 char *p; 638 639 *long_val = strtoull(ptr, &p, 16); 640 641 return p - ptr; 642 } 643 644 645 int modules__parse(const char *filename, void *arg, 646 int (*process_module)(void *arg, const char *name, 647 u64 start, u64 size)) 648 { 649 char *line = NULL; 650 size_t n; 651 FILE *file; 652 int err = 0; 653 654 file = fopen(filename, "r"); 655 if (file == NULL) 656 return -1; 657 658 while (1) { 659 char name[PATH_MAX]; 660 u64 start, size; 661 char *sep, *endptr; 662 ssize_t line_len; 663 664 line_len = getline(&line, &n, file); 665 if (line_len < 0) { 666 if (feof(file)) 667 break; 668 err = -1; 669 goto out; 670 } 671 672 if (!line) { 673 err = -1; 674 goto out; 675 } 676 677 line[--line_len] = '\0'; /* \n */ 678 679 sep = strrchr(line, 'x'); 680 if (sep == NULL) 681 continue; 682 683 hex2u64(sep + 1, &start); 684 685 sep = strchr(line, ' '); 686 if (sep == NULL) 687 continue; 688 689 *sep = '\0'; 690 691 scnprintf(name, sizeof(name), "[%s]", line); 692 693 size = strtoul(sep + 1, &endptr, 0); 694 if (*endptr != ' ' && *endptr != '\t') 695 continue; 696 697 err = process_module(arg, name, start, size); 698 if (err) 699 break; 700 } 701 out: 702 free(line); 703 fclose(file); 704 return err; 705 } 706 707 /* 708 * These are symbols in the kernel image, so make sure that 709 * sym is from a kernel DSO. 710 */ 711 static bool symbol__is_idle(const char *name) 712 { 713 const char * const idle_symbols[] = { 714 "acpi_idle_do_entry", 715 "acpi_processor_ffh_cstate_enter", 716 "arch_cpu_idle", 717 "cpu_idle", 718 "cpu_startup_entry", 719 "idle_cpu", 720 "intel_idle", 721 "intel_idle_ibrs", 722 "default_idle", 723 "native_safe_halt", 724 "enter_idle", 725 "exit_idle", 726 "mwait_idle", 727 "mwait_idle_with_hints", 728 "mwait_idle_with_hints.constprop.0", 729 "poll_idle", 730 "ppc64_runlatch_off", 731 "pseries_dedicated_idle_sleep", 732 "psw_idle", 733 "psw_idle_exit", 734 NULL 735 }; 736 int i; 737 static struct strlist *idle_symbols_list; 738 739 if (idle_symbols_list) 740 return strlist__has_entry(idle_symbols_list, name); 741 742 idle_symbols_list = strlist__new(NULL, NULL); 743 744 for (i = 0; idle_symbols[i]; i++) 745 strlist__add(idle_symbols_list, idle_symbols[i]); 746 747 return strlist__has_entry(idle_symbols_list, name); 748 } 749 750 static int map__process_kallsym_symbol(void *arg, const char *name, 751 char type, u64 start) 752 { 753 struct symbol *sym; 754 struct dso *dso = arg; 755 struct rb_root_cached *root = &dso->symbols; 756 757 if (!symbol_type__filter(type)) 758 return 0; 759 760 /* Ignore local symbols for ARM modules */ 761 if (name[0] == '$') 762 return 0; 763 764 /* 765 * module symbols are not sorted so we add all 766 * symbols, setting length to 0, and rely on 767 * symbols__fixup_end() to fix it up. 768 */ 769 sym = symbol__new(start, 0, kallsyms2elf_binding(type), kallsyms2elf_type(type), name); 770 if (sym == NULL) 771 return -ENOMEM; 772 /* 773 * We will pass the symbols to the filter later, in 774 * map__split_kallsyms, when we have split the maps per module 775 */ 776 __symbols__insert(root, sym, !strchr(name, '[')); 777 778 return 0; 779 } 780 781 /* 782 * Loads the function entries in /proc/kallsyms into kernel_map->dso, 783 * so that we can in the next step set the symbol ->end address and then 784 * call kernel_maps__split_kallsyms. 785 */ 786 static int dso__load_all_kallsyms(struct dso *dso, const char *filename) 787 { 788 return kallsyms__parse(filename, dso, map__process_kallsym_symbol); 789 } 790 791 static int maps__split_kallsyms_for_kcore(struct maps *kmaps, struct dso *dso) 792 { 793 struct map *curr_map; 794 struct symbol *pos; 795 int count = 0; 796 struct rb_root_cached old_root = dso->symbols; 797 struct rb_root_cached *root = &dso->symbols; 798 struct rb_node *next = rb_first_cached(root); 799 800 if (!kmaps) 801 return -1; 802 803 *root = RB_ROOT_CACHED; 804 805 while (next) { 806 struct dso *curr_map_dso; 807 char *module; 808 809 pos = rb_entry(next, struct symbol, rb_node); 810 next = rb_next(&pos->rb_node); 811 812 rb_erase_cached(&pos->rb_node, &old_root); 813 RB_CLEAR_NODE(&pos->rb_node); 814 module = strchr(pos->name, '\t'); 815 if (module) 816 *module = '\0'; 817 818 curr_map = maps__find(kmaps, pos->start); 819 820 if (!curr_map) { 821 symbol__delete(pos); 822 continue; 823 } 824 curr_map_dso = map__dso(curr_map); 825 pos->start -= map__start(curr_map) - map__pgoff(curr_map); 826 if (pos->end > map__end(curr_map)) 827 pos->end = map__end(curr_map); 828 if (pos->end) 829 pos->end -= map__start(curr_map) - map__pgoff(curr_map); 830 symbols__insert(&curr_map_dso->symbols, pos); 831 ++count; 832 } 833 834 /* Symbols have been adjusted */ 835 dso->adjust_symbols = 1; 836 837 return count; 838 } 839 840 /* 841 * Split the symbols into maps, making sure there are no overlaps, i.e. the 842 * kernel range is broken in several maps, named [kernel].N, as we don't have 843 * the original ELF section names vmlinux have. 844 */ 845 static int maps__split_kallsyms(struct maps *kmaps, struct dso *dso, u64 delta, 846 struct map *initial_map) 847 { 848 struct machine *machine; 849 struct map *curr_map = initial_map; 850 struct symbol *pos; 851 int count = 0, moved = 0; 852 struct rb_root_cached *root = &dso->symbols; 853 struct rb_node *next = rb_first_cached(root); 854 int kernel_range = 0; 855 bool x86_64; 856 857 if (!kmaps) 858 return -1; 859 860 machine = maps__machine(kmaps); 861 862 x86_64 = machine__is(machine, "x86_64"); 863 864 while (next) { 865 char *module; 866 867 pos = rb_entry(next, struct symbol, rb_node); 868 next = rb_next(&pos->rb_node); 869 870 module = strchr(pos->name, '\t'); 871 if (module) { 872 struct dso *curr_map_dso; 873 874 if (!symbol_conf.use_modules) 875 goto discard_symbol; 876 877 *module++ = '\0'; 878 curr_map_dso = map__dso(curr_map); 879 if (strcmp(curr_map_dso->short_name, module)) { 880 if (!RC_CHK_EQUAL(curr_map, initial_map) && 881 dso->kernel == DSO_SPACE__KERNEL_GUEST && 882 machine__is_default_guest(machine)) { 883 /* 884 * We assume all symbols of a module are 885 * continuous in * kallsyms, so curr_map 886 * points to a module and all its 887 * symbols are in its kmap. Mark it as 888 * loaded. 889 */ 890 dso__set_loaded(curr_map_dso); 891 } 892 893 curr_map = maps__find_by_name(kmaps, module); 894 if (curr_map == NULL) { 895 pr_debug("%s/proc/{kallsyms,modules} " 896 "inconsistency while looking " 897 "for \"%s\" module!\n", 898 machine->root_dir, module); 899 curr_map = initial_map; 900 goto discard_symbol; 901 } 902 curr_map_dso = map__dso(curr_map); 903 if (curr_map_dso->loaded && 904 !machine__is_default_guest(machine)) 905 goto discard_symbol; 906 } 907 /* 908 * So that we look just like we get from .ko files, 909 * i.e. not prelinked, relative to initial_map->start. 910 */ 911 pos->start = map__map_ip(curr_map, pos->start); 912 pos->end = map__map_ip(curr_map, pos->end); 913 } else if (x86_64 && is_entry_trampoline(pos->name)) { 914 /* 915 * These symbols are not needed anymore since the 916 * trampoline maps refer to the text section and it's 917 * symbols instead. Avoid having to deal with 918 * relocations, and the assumption that the first symbol 919 * is the start of kernel text, by simply removing the 920 * symbols at this point. 921 */ 922 goto discard_symbol; 923 } else if (curr_map != initial_map) { 924 char dso_name[PATH_MAX]; 925 struct dso *ndso; 926 927 if (delta) { 928 /* Kernel was relocated at boot time */ 929 pos->start -= delta; 930 pos->end -= delta; 931 } 932 933 if (count == 0) { 934 curr_map = initial_map; 935 goto add_symbol; 936 } 937 938 if (dso->kernel == DSO_SPACE__KERNEL_GUEST) 939 snprintf(dso_name, sizeof(dso_name), 940 "[guest.kernel].%d", 941 kernel_range++); 942 else 943 snprintf(dso_name, sizeof(dso_name), 944 "[kernel].%d", 945 kernel_range++); 946 947 ndso = dso__new(dso_name); 948 if (ndso == NULL) 949 return -1; 950 951 ndso->kernel = dso->kernel; 952 953 curr_map = map__new2(pos->start, ndso); 954 if (curr_map == NULL) { 955 dso__put(ndso); 956 return -1; 957 } 958 959 map__set_map_ip(curr_map, identity__map_ip); 960 map__set_unmap_ip(curr_map, identity__map_ip); 961 if (maps__insert(kmaps, curr_map)) { 962 dso__put(ndso); 963 return -1; 964 } 965 ++kernel_range; 966 } else if (delta) { 967 /* Kernel was relocated at boot time */ 968 pos->start -= delta; 969 pos->end -= delta; 970 } 971 add_symbol: 972 if (curr_map != initial_map) { 973 struct dso *curr_map_dso = map__dso(curr_map); 974 975 rb_erase_cached(&pos->rb_node, root); 976 symbols__insert(&curr_map_dso->symbols, pos); 977 ++moved; 978 } else 979 ++count; 980 981 continue; 982 discard_symbol: 983 rb_erase_cached(&pos->rb_node, root); 984 symbol__delete(pos); 985 } 986 987 if (curr_map != initial_map && 988 dso->kernel == DSO_SPACE__KERNEL_GUEST && 989 machine__is_default_guest(maps__machine(kmaps))) { 990 dso__set_loaded(map__dso(curr_map)); 991 } 992 993 return count + moved; 994 } 995 996 bool symbol__restricted_filename(const char *filename, 997 const char *restricted_filename) 998 { 999 bool restricted = false; 1000 1001 if (symbol_conf.kptr_restrict) { 1002 char *r = realpath(filename, NULL); 1003 1004 if (r != NULL) { 1005 restricted = strcmp(r, restricted_filename) == 0; 1006 free(r); 1007 return restricted; 1008 } 1009 } 1010 1011 return restricted; 1012 } 1013 1014 struct module_info { 1015 struct rb_node rb_node; 1016 char *name; 1017 u64 start; 1018 }; 1019 1020 static void add_module(struct module_info *mi, struct rb_root *modules) 1021 { 1022 struct rb_node **p = &modules->rb_node; 1023 struct rb_node *parent = NULL; 1024 struct module_info *m; 1025 1026 while (*p != NULL) { 1027 parent = *p; 1028 m = rb_entry(parent, struct module_info, rb_node); 1029 if (strcmp(mi->name, m->name) < 0) 1030 p = &(*p)->rb_left; 1031 else 1032 p = &(*p)->rb_right; 1033 } 1034 rb_link_node(&mi->rb_node, parent, p); 1035 rb_insert_color(&mi->rb_node, modules); 1036 } 1037 1038 static void delete_modules(struct rb_root *modules) 1039 { 1040 struct module_info *mi; 1041 struct rb_node *next = rb_first(modules); 1042 1043 while (next) { 1044 mi = rb_entry(next, struct module_info, rb_node); 1045 next = rb_next(&mi->rb_node); 1046 rb_erase(&mi->rb_node, modules); 1047 zfree(&mi->name); 1048 free(mi); 1049 } 1050 } 1051 1052 static struct module_info *find_module(const char *name, 1053 struct rb_root *modules) 1054 { 1055 struct rb_node *n = modules->rb_node; 1056 1057 while (n) { 1058 struct module_info *m; 1059 int cmp; 1060 1061 m = rb_entry(n, struct module_info, rb_node); 1062 cmp = strcmp(name, m->name); 1063 if (cmp < 0) 1064 n = n->rb_left; 1065 else if (cmp > 0) 1066 n = n->rb_right; 1067 else 1068 return m; 1069 } 1070 1071 return NULL; 1072 } 1073 1074 static int __read_proc_modules(void *arg, const char *name, u64 start, 1075 u64 size __maybe_unused) 1076 { 1077 struct rb_root *modules = arg; 1078 struct module_info *mi; 1079 1080 mi = zalloc(sizeof(struct module_info)); 1081 if (!mi) 1082 return -ENOMEM; 1083 1084 mi->name = strdup(name); 1085 mi->start = start; 1086 1087 if (!mi->name) { 1088 free(mi); 1089 return -ENOMEM; 1090 } 1091 1092 add_module(mi, modules); 1093 1094 return 0; 1095 } 1096 1097 static int read_proc_modules(const char *filename, struct rb_root *modules) 1098 { 1099 if (symbol__restricted_filename(filename, "/proc/modules")) 1100 return -1; 1101 1102 if (modules__parse(filename, modules, __read_proc_modules)) { 1103 delete_modules(modules); 1104 return -1; 1105 } 1106 1107 return 0; 1108 } 1109 1110 int compare_proc_modules(const char *from, const char *to) 1111 { 1112 struct rb_root from_modules = RB_ROOT; 1113 struct rb_root to_modules = RB_ROOT; 1114 struct rb_node *from_node, *to_node; 1115 struct module_info *from_m, *to_m; 1116 int ret = -1; 1117 1118 if (read_proc_modules(from, &from_modules)) 1119 return -1; 1120 1121 if (read_proc_modules(to, &to_modules)) 1122 goto out_delete_from; 1123 1124 from_node = rb_first(&from_modules); 1125 to_node = rb_first(&to_modules); 1126 while (from_node) { 1127 if (!to_node) 1128 break; 1129 1130 from_m = rb_entry(from_node, struct module_info, rb_node); 1131 to_m = rb_entry(to_node, struct module_info, rb_node); 1132 1133 if (from_m->start != to_m->start || 1134 strcmp(from_m->name, to_m->name)) 1135 break; 1136 1137 from_node = rb_next(from_node); 1138 to_node = rb_next(to_node); 1139 } 1140 1141 if (!from_node && !to_node) 1142 ret = 0; 1143 1144 delete_modules(&to_modules); 1145 out_delete_from: 1146 delete_modules(&from_modules); 1147 1148 return ret; 1149 } 1150 1151 static int do_validate_kcore_modules(const char *filename, struct maps *kmaps) 1152 { 1153 struct rb_root modules = RB_ROOT; 1154 struct map_rb_node *old_node; 1155 int err; 1156 1157 err = read_proc_modules(filename, &modules); 1158 if (err) 1159 return err; 1160 1161 maps__for_each_entry(kmaps, old_node) { 1162 struct map *old_map = old_node->map; 1163 struct module_info *mi; 1164 struct dso *dso; 1165 1166 if (!__map__is_kmodule(old_map)) { 1167 continue; 1168 } 1169 dso = map__dso(old_map); 1170 /* Module must be in memory at the same address */ 1171 mi = find_module(dso->short_name, &modules); 1172 if (!mi || mi->start != map__start(old_map)) { 1173 err = -EINVAL; 1174 goto out; 1175 } 1176 } 1177 out: 1178 delete_modules(&modules); 1179 return err; 1180 } 1181 1182 /* 1183 * If kallsyms is referenced by name then we look for filename in the same 1184 * directory. 1185 */ 1186 static bool filename_from_kallsyms_filename(char *filename, 1187 const char *base_name, 1188 const char *kallsyms_filename) 1189 { 1190 char *name; 1191 1192 strcpy(filename, kallsyms_filename); 1193 name = strrchr(filename, '/'); 1194 if (!name) 1195 return false; 1196 1197 name += 1; 1198 1199 if (!strcmp(name, "kallsyms")) { 1200 strcpy(name, base_name); 1201 return true; 1202 } 1203 1204 return false; 1205 } 1206 1207 static int validate_kcore_modules(const char *kallsyms_filename, 1208 struct map *map) 1209 { 1210 struct maps *kmaps = map__kmaps(map); 1211 char modules_filename[PATH_MAX]; 1212 1213 if (!kmaps) 1214 return -EINVAL; 1215 1216 if (!filename_from_kallsyms_filename(modules_filename, "modules", 1217 kallsyms_filename)) 1218 return -EINVAL; 1219 1220 if (do_validate_kcore_modules(modules_filename, kmaps)) 1221 return -EINVAL; 1222 1223 return 0; 1224 } 1225 1226 static int validate_kcore_addresses(const char *kallsyms_filename, 1227 struct map *map) 1228 { 1229 struct kmap *kmap = map__kmap(map); 1230 1231 if (!kmap) 1232 return -EINVAL; 1233 1234 if (kmap->ref_reloc_sym && kmap->ref_reloc_sym->name) { 1235 u64 start; 1236 1237 if (kallsyms__get_function_start(kallsyms_filename, 1238 kmap->ref_reloc_sym->name, &start)) 1239 return -ENOENT; 1240 if (start != kmap->ref_reloc_sym->addr) 1241 return -EINVAL; 1242 } 1243 1244 return validate_kcore_modules(kallsyms_filename, map); 1245 } 1246 1247 struct kcore_mapfn_data { 1248 struct dso *dso; 1249 struct list_head maps; 1250 }; 1251 1252 static int kcore_mapfn(u64 start, u64 len, u64 pgoff, void *data) 1253 { 1254 struct kcore_mapfn_data *md = data; 1255 struct map_list_node *list_node = map_list_node__new(); 1256 1257 if (!list_node) 1258 return -ENOMEM; 1259 1260 list_node->map = map__new2(start, md->dso); 1261 if (!list_node->map) { 1262 free(list_node); 1263 return -ENOMEM; 1264 } 1265 1266 map__set_end(list_node->map, map__start(list_node->map) + len); 1267 map__set_pgoff(list_node->map, pgoff); 1268 1269 list_add(&list_node->node, &md->maps); 1270 1271 return 0; 1272 } 1273 1274 /* 1275 * Merges map into maps by splitting the new map within the existing map 1276 * regions. 1277 */ 1278 int maps__merge_in(struct maps *kmaps, struct map *new_map) 1279 { 1280 struct map_rb_node *rb_node; 1281 LIST_HEAD(merged); 1282 int err = 0; 1283 1284 maps__for_each_entry(kmaps, rb_node) { 1285 struct map *old_map = rb_node->map; 1286 1287 /* no overload with this one */ 1288 if (map__end(new_map) < map__start(old_map) || 1289 map__start(new_map) >= map__end(old_map)) 1290 continue; 1291 1292 if (map__start(new_map) < map__start(old_map)) { 1293 /* 1294 * |new...... 1295 * |old.... 1296 */ 1297 if (map__end(new_map) < map__end(old_map)) { 1298 /* 1299 * |new......| -> |new..| 1300 * |old....| -> |old....| 1301 */ 1302 map__set_end(new_map, map__start(old_map)); 1303 } else { 1304 /* 1305 * |new.............| -> |new..| |new..| 1306 * |old....| -> |old....| 1307 */ 1308 struct map_list_node *m = map_list_node__new(); 1309 1310 if (!m) { 1311 err = -ENOMEM; 1312 goto out; 1313 } 1314 1315 m->map = map__clone(new_map); 1316 if (!m->map) { 1317 free(m); 1318 err = -ENOMEM; 1319 goto out; 1320 } 1321 1322 map__set_end(m->map, map__start(old_map)); 1323 list_add_tail(&m->node, &merged); 1324 map__add_pgoff(new_map, map__end(old_map) - map__start(new_map)); 1325 map__set_start(new_map, map__end(old_map)); 1326 } 1327 } else { 1328 /* 1329 * |new...... 1330 * |old.... 1331 */ 1332 if (map__end(new_map) < map__end(old_map)) { 1333 /* 1334 * |new..| -> x 1335 * |old.........| -> |old.........| 1336 */ 1337 map__put(new_map); 1338 new_map = NULL; 1339 break; 1340 } else { 1341 /* 1342 * |new......| -> |new...| 1343 * |old....| -> |old....| 1344 */ 1345 map__add_pgoff(new_map, map__end(old_map) - map__start(new_map)); 1346 map__set_start(new_map, map__end(old_map)); 1347 } 1348 } 1349 } 1350 1351 out: 1352 while (!list_empty(&merged)) { 1353 struct map_list_node *old_node; 1354 1355 old_node = list_entry(merged.next, struct map_list_node, node); 1356 list_del_init(&old_node->node); 1357 if (!err) 1358 err = maps__insert(kmaps, old_node->map); 1359 map__put(old_node->map); 1360 free(old_node); 1361 } 1362 1363 if (new_map) { 1364 if (!err) 1365 err = maps__insert(kmaps, new_map); 1366 map__put(new_map); 1367 } 1368 return err; 1369 } 1370 1371 static int dso__load_kcore(struct dso *dso, struct map *map, 1372 const char *kallsyms_filename) 1373 { 1374 struct maps *kmaps = map__kmaps(map); 1375 struct kcore_mapfn_data md; 1376 struct map *replacement_map = NULL; 1377 struct map_rb_node *old_node, *next; 1378 struct machine *machine; 1379 bool is_64_bit; 1380 int err, fd; 1381 char kcore_filename[PATH_MAX]; 1382 u64 stext; 1383 1384 if (!kmaps) 1385 return -EINVAL; 1386 1387 machine = maps__machine(kmaps); 1388 1389 /* This function requires that the map is the kernel map */ 1390 if (!__map__is_kernel(map)) 1391 return -EINVAL; 1392 1393 if (!filename_from_kallsyms_filename(kcore_filename, "kcore", 1394 kallsyms_filename)) 1395 return -EINVAL; 1396 1397 /* Modules and kernel must be present at their original addresses */ 1398 if (validate_kcore_addresses(kallsyms_filename, map)) 1399 return -EINVAL; 1400 1401 md.dso = dso; 1402 INIT_LIST_HEAD(&md.maps); 1403 1404 fd = open(kcore_filename, O_RDONLY); 1405 if (fd < 0) { 1406 pr_debug("Failed to open %s. Note /proc/kcore requires CAP_SYS_RAWIO capability to access.\n", 1407 kcore_filename); 1408 return -EINVAL; 1409 } 1410 1411 /* Read new maps into temporary lists */ 1412 err = file__read_maps(fd, map__prot(map) & PROT_EXEC, kcore_mapfn, &md, 1413 &is_64_bit); 1414 if (err) 1415 goto out_err; 1416 dso->is_64_bit = is_64_bit; 1417 1418 if (list_empty(&md.maps)) { 1419 err = -EINVAL; 1420 goto out_err; 1421 } 1422 1423 /* Remove old maps */ 1424 maps__for_each_entry_safe(kmaps, old_node, next) { 1425 struct map *old_map = old_node->map; 1426 1427 /* 1428 * We need to preserve eBPF maps even if they are 1429 * covered by kcore, because we need to access 1430 * eBPF dso for source data. 1431 */ 1432 if (old_map != map && !__map__is_bpf_prog(old_map)) 1433 maps__remove(kmaps, old_map); 1434 } 1435 machine->trampolines_mapped = false; 1436 1437 /* Find the kernel map using the '_stext' symbol */ 1438 if (!kallsyms__get_function_start(kallsyms_filename, "_stext", &stext)) { 1439 u64 replacement_size = 0; 1440 struct map_list_node *new_node; 1441 1442 list_for_each_entry(new_node, &md.maps, node) { 1443 struct map *new_map = new_node->map; 1444 u64 new_size = map__size(new_map); 1445 1446 if (!(stext >= map__start(new_map) && stext < map__end(new_map))) 1447 continue; 1448 1449 /* 1450 * On some architectures, ARM64 for example, the kernel 1451 * text can get allocated inside of the vmalloc segment. 1452 * Select the smallest matching segment, in case stext 1453 * falls within more than one in the list. 1454 */ 1455 if (!replacement_map || new_size < replacement_size) { 1456 replacement_map = new_map; 1457 replacement_size = new_size; 1458 } 1459 } 1460 } 1461 1462 if (!replacement_map) 1463 replacement_map = list_entry(md.maps.next, struct map_list_node, node)->map; 1464 1465 /* Add new maps */ 1466 while (!list_empty(&md.maps)) { 1467 struct map_list_node *new_node = list_entry(md.maps.next, struct map_list_node, node); 1468 struct map *new_map = new_node->map; 1469 1470 list_del_init(&new_node->node); 1471 1472 if (RC_CHK_EQUAL(new_map, replacement_map)) { 1473 struct map *map_ref; 1474 1475 map__set_start(map, map__start(new_map)); 1476 map__set_end(map, map__end(new_map)); 1477 map__set_pgoff(map, map__pgoff(new_map)); 1478 map__set_map_ip(map, map__map_ip_ptr(new_map)); 1479 map__set_unmap_ip(map, map__unmap_ip_ptr(new_map)); 1480 /* Ensure maps are correctly ordered */ 1481 map_ref = map__get(map); 1482 maps__remove(kmaps, map_ref); 1483 err = maps__insert(kmaps, map_ref); 1484 map__put(map_ref); 1485 map__put(new_map); 1486 if (err) 1487 goto out_err; 1488 } else { 1489 /* 1490 * Merge kcore map into existing maps, 1491 * and ensure that current maps (eBPF) 1492 * stay intact. 1493 */ 1494 if (maps__merge_in(kmaps, new_map)) { 1495 err = -EINVAL; 1496 goto out_err; 1497 } 1498 } 1499 free(new_node); 1500 } 1501 1502 if (machine__is(machine, "x86_64")) { 1503 u64 addr; 1504 1505 /* 1506 * If one of the corresponding symbols is there, assume the 1507 * entry trampoline maps are too. 1508 */ 1509 if (!kallsyms__get_function_start(kallsyms_filename, 1510 ENTRY_TRAMPOLINE_NAME, 1511 &addr)) 1512 machine->trampolines_mapped = true; 1513 } 1514 1515 /* 1516 * Set the data type and long name so that kcore can be read via 1517 * dso__data_read_addr(). 1518 */ 1519 if (dso->kernel == DSO_SPACE__KERNEL_GUEST) 1520 dso->binary_type = DSO_BINARY_TYPE__GUEST_KCORE; 1521 else 1522 dso->binary_type = DSO_BINARY_TYPE__KCORE; 1523 dso__set_long_name(dso, strdup(kcore_filename), true); 1524 1525 close(fd); 1526 1527 if (map__prot(map) & PROT_EXEC) 1528 pr_debug("Using %s for kernel object code\n", kcore_filename); 1529 else 1530 pr_debug("Using %s for kernel data\n", kcore_filename); 1531 1532 return 0; 1533 1534 out_err: 1535 while (!list_empty(&md.maps)) { 1536 struct map_list_node *list_node; 1537 1538 list_node = list_entry(md.maps.next, struct map_list_node, node); 1539 list_del_init(&list_node->node); 1540 map__zput(list_node->map); 1541 free(list_node); 1542 } 1543 close(fd); 1544 return err; 1545 } 1546 1547 /* 1548 * If the kernel is relocated at boot time, kallsyms won't match. Compute the 1549 * delta based on the relocation reference symbol. 1550 */ 1551 static int kallsyms__delta(struct kmap *kmap, const char *filename, u64 *delta) 1552 { 1553 u64 addr; 1554 1555 if (!kmap->ref_reloc_sym || !kmap->ref_reloc_sym->name) 1556 return 0; 1557 1558 if (kallsyms__get_function_start(filename, kmap->ref_reloc_sym->name, &addr)) 1559 return -1; 1560 1561 *delta = addr - kmap->ref_reloc_sym->addr; 1562 return 0; 1563 } 1564 1565 int __dso__load_kallsyms(struct dso *dso, const char *filename, 1566 struct map *map, bool no_kcore) 1567 { 1568 struct kmap *kmap = map__kmap(map); 1569 u64 delta = 0; 1570 1571 if (symbol__restricted_filename(filename, "/proc/kallsyms")) 1572 return -1; 1573 1574 if (!kmap || !kmap->kmaps) 1575 return -1; 1576 1577 if (dso__load_all_kallsyms(dso, filename) < 0) 1578 return -1; 1579 1580 if (kallsyms__delta(kmap, filename, &delta)) 1581 return -1; 1582 1583 symbols__fixup_end(&dso->symbols, true); 1584 symbols__fixup_duplicate(&dso->symbols); 1585 1586 if (dso->kernel == DSO_SPACE__KERNEL_GUEST) 1587 dso->symtab_type = DSO_BINARY_TYPE__GUEST_KALLSYMS; 1588 else 1589 dso->symtab_type = DSO_BINARY_TYPE__KALLSYMS; 1590 1591 if (!no_kcore && !dso__load_kcore(dso, map, filename)) 1592 return maps__split_kallsyms_for_kcore(kmap->kmaps, dso); 1593 else 1594 return maps__split_kallsyms(kmap->kmaps, dso, delta, map); 1595 } 1596 1597 int dso__load_kallsyms(struct dso *dso, const char *filename, 1598 struct map *map) 1599 { 1600 return __dso__load_kallsyms(dso, filename, map, false); 1601 } 1602 1603 static int dso__load_perf_map(const char *map_path, struct dso *dso) 1604 { 1605 char *line = NULL; 1606 size_t n; 1607 FILE *file; 1608 int nr_syms = 0; 1609 1610 file = fopen(map_path, "r"); 1611 if (file == NULL) 1612 goto out_failure; 1613 1614 while (!feof(file)) { 1615 u64 start, size; 1616 struct symbol *sym; 1617 int line_len, len; 1618 1619 line_len = getline(&line, &n, file); 1620 if (line_len < 0) 1621 break; 1622 1623 if (!line) 1624 goto out_failure; 1625 1626 line[--line_len] = '\0'; /* \n */ 1627 1628 len = hex2u64(line, &start); 1629 1630 len++; 1631 if (len + 2 >= line_len) 1632 continue; 1633 1634 len += hex2u64(line + len, &size); 1635 1636 len++; 1637 if (len + 2 >= line_len) 1638 continue; 1639 1640 sym = symbol__new(start, size, STB_GLOBAL, STT_FUNC, line + len); 1641 1642 if (sym == NULL) 1643 goto out_delete_line; 1644 1645 symbols__insert(&dso->symbols, sym); 1646 nr_syms++; 1647 } 1648 1649 free(line); 1650 fclose(file); 1651 1652 return nr_syms; 1653 1654 out_delete_line: 1655 free(line); 1656 out_failure: 1657 return -1; 1658 } 1659 1660 #ifdef HAVE_LIBBFD_SUPPORT 1661 #define PACKAGE 'perf' 1662 #include <bfd.h> 1663 1664 static int bfd_symbols__cmpvalue(const void *a, const void *b) 1665 { 1666 const asymbol *as = *(const asymbol **)a, *bs = *(const asymbol **)b; 1667 1668 if (bfd_asymbol_value(as) != bfd_asymbol_value(bs)) 1669 return bfd_asymbol_value(as) - bfd_asymbol_value(bs); 1670 1671 return bfd_asymbol_name(as)[0] - bfd_asymbol_name(bs)[0]; 1672 } 1673 1674 static int bfd2elf_binding(asymbol *symbol) 1675 { 1676 if (symbol->flags & BSF_WEAK) 1677 return STB_WEAK; 1678 if (symbol->flags & BSF_GLOBAL) 1679 return STB_GLOBAL; 1680 if (symbol->flags & BSF_LOCAL) 1681 return STB_LOCAL; 1682 return -1; 1683 } 1684 1685 int dso__load_bfd_symbols(struct dso *dso, const char *debugfile) 1686 { 1687 int err = -1; 1688 long symbols_size, symbols_count, i; 1689 asection *section; 1690 asymbol **symbols, *sym; 1691 struct symbol *symbol; 1692 bfd *abfd; 1693 u64 start, len; 1694 1695 abfd = bfd_openr(debugfile, NULL); 1696 if (!abfd) 1697 return -1; 1698 1699 if (!bfd_check_format(abfd, bfd_object)) { 1700 pr_debug2("%s: cannot read %s bfd file.\n", __func__, 1701 dso->long_name); 1702 goto out_close; 1703 } 1704 1705 if (bfd_get_flavour(abfd) == bfd_target_elf_flavour) 1706 goto out_close; 1707 1708 symbols_size = bfd_get_symtab_upper_bound(abfd); 1709 if (symbols_size == 0) { 1710 bfd_close(abfd); 1711 return 0; 1712 } 1713 1714 if (symbols_size < 0) 1715 goto out_close; 1716 1717 symbols = malloc(symbols_size); 1718 if (!symbols) 1719 goto out_close; 1720 1721 symbols_count = bfd_canonicalize_symtab(abfd, symbols); 1722 if (symbols_count < 0) 1723 goto out_free; 1724 1725 section = bfd_get_section_by_name(abfd, ".text"); 1726 if (section) { 1727 for (i = 0; i < symbols_count; ++i) { 1728 if (!strcmp(bfd_asymbol_name(symbols[i]), "__ImageBase") || 1729 !strcmp(bfd_asymbol_name(symbols[i]), "__image_base__")) 1730 break; 1731 } 1732 if (i < symbols_count) { 1733 /* PE symbols can only have 4 bytes, so use .text high bits */ 1734 dso->text_offset = section->vma - (u32)section->vma; 1735 dso->text_offset += (u32)bfd_asymbol_value(symbols[i]); 1736 dso->text_end = (section->vma - dso->text_offset) + section->size; 1737 } else { 1738 dso->text_offset = section->vma - section->filepos; 1739 dso->text_end = section->filepos + section->size; 1740 } 1741 } 1742 1743 qsort(symbols, symbols_count, sizeof(asymbol *), bfd_symbols__cmpvalue); 1744 1745 #ifdef bfd_get_section 1746 #define bfd_asymbol_section bfd_get_section 1747 #endif 1748 for (i = 0; i < symbols_count; ++i) { 1749 sym = symbols[i]; 1750 section = bfd_asymbol_section(sym); 1751 if (bfd2elf_binding(sym) < 0) 1752 continue; 1753 1754 while (i + 1 < symbols_count && 1755 bfd_asymbol_section(symbols[i + 1]) == section && 1756 bfd2elf_binding(symbols[i + 1]) < 0) 1757 i++; 1758 1759 if (i + 1 < symbols_count && 1760 bfd_asymbol_section(symbols[i + 1]) == section) 1761 len = symbols[i + 1]->value - sym->value; 1762 else 1763 len = section->size - sym->value; 1764 1765 start = bfd_asymbol_value(sym) - dso->text_offset; 1766 symbol = symbol__new(start, len, bfd2elf_binding(sym), STT_FUNC, 1767 bfd_asymbol_name(sym)); 1768 if (!symbol) 1769 goto out_free; 1770 1771 symbols__insert(&dso->symbols, symbol); 1772 } 1773 #ifdef bfd_get_section 1774 #undef bfd_asymbol_section 1775 #endif 1776 1777 symbols__fixup_end(&dso->symbols, false); 1778 symbols__fixup_duplicate(&dso->symbols); 1779 dso->adjust_symbols = 1; 1780 1781 err = 0; 1782 out_free: 1783 free(symbols); 1784 out_close: 1785 bfd_close(abfd); 1786 return err; 1787 } 1788 #endif 1789 1790 static bool dso__is_compatible_symtab_type(struct dso *dso, bool kmod, 1791 enum dso_binary_type type) 1792 { 1793 switch (type) { 1794 case DSO_BINARY_TYPE__JAVA_JIT: 1795 case DSO_BINARY_TYPE__DEBUGLINK: 1796 case DSO_BINARY_TYPE__SYSTEM_PATH_DSO: 1797 case DSO_BINARY_TYPE__FEDORA_DEBUGINFO: 1798 case DSO_BINARY_TYPE__UBUNTU_DEBUGINFO: 1799 case DSO_BINARY_TYPE__MIXEDUP_UBUNTU_DEBUGINFO: 1800 case DSO_BINARY_TYPE__BUILDID_DEBUGINFO: 1801 case DSO_BINARY_TYPE__OPENEMBEDDED_DEBUGINFO: 1802 return !kmod && dso->kernel == DSO_SPACE__USER; 1803 1804 case DSO_BINARY_TYPE__KALLSYMS: 1805 case DSO_BINARY_TYPE__VMLINUX: 1806 case DSO_BINARY_TYPE__KCORE: 1807 return dso->kernel == DSO_SPACE__KERNEL; 1808 1809 case DSO_BINARY_TYPE__GUEST_KALLSYMS: 1810 case DSO_BINARY_TYPE__GUEST_VMLINUX: 1811 case DSO_BINARY_TYPE__GUEST_KCORE: 1812 return dso->kernel == DSO_SPACE__KERNEL_GUEST; 1813 1814 case DSO_BINARY_TYPE__GUEST_KMODULE: 1815 case DSO_BINARY_TYPE__GUEST_KMODULE_COMP: 1816 case DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE: 1817 case DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP: 1818 /* 1819 * kernel modules know their symtab type - it's set when 1820 * creating a module dso in machine__addnew_module_map(). 1821 */ 1822 return kmod && dso->symtab_type == type; 1823 1824 case DSO_BINARY_TYPE__BUILD_ID_CACHE: 1825 case DSO_BINARY_TYPE__BUILD_ID_CACHE_DEBUGINFO: 1826 return true; 1827 1828 case DSO_BINARY_TYPE__BPF_PROG_INFO: 1829 case DSO_BINARY_TYPE__BPF_IMAGE: 1830 case DSO_BINARY_TYPE__OOL: 1831 case DSO_BINARY_TYPE__NOT_FOUND: 1832 default: 1833 return false; 1834 } 1835 } 1836 1837 /* Checks for the existence of the perf-<pid>.map file in two different 1838 * locations. First, if the process is a separate mount namespace, check in 1839 * that namespace using the pid of the innermost pid namespace. If's not in a 1840 * namespace, or the file can't be found there, try in the mount namespace of 1841 * the tracing process using our view of its pid. 1842 */ 1843 static int dso__find_perf_map(char *filebuf, size_t bufsz, 1844 struct nsinfo **nsip) 1845 { 1846 struct nscookie nsc; 1847 struct nsinfo *nsi; 1848 struct nsinfo *nnsi; 1849 int rc = -1; 1850 1851 nsi = *nsip; 1852 1853 if (nsinfo__need_setns(nsi)) { 1854 snprintf(filebuf, bufsz, "/tmp/perf-%d.map", nsinfo__nstgid(nsi)); 1855 nsinfo__mountns_enter(nsi, &nsc); 1856 rc = access(filebuf, R_OK); 1857 nsinfo__mountns_exit(&nsc); 1858 if (rc == 0) 1859 return rc; 1860 } 1861 1862 nnsi = nsinfo__copy(nsi); 1863 if (nnsi) { 1864 nsinfo__put(nsi); 1865 1866 nsinfo__clear_need_setns(nnsi); 1867 snprintf(filebuf, bufsz, "/tmp/perf-%d.map", nsinfo__tgid(nnsi)); 1868 *nsip = nnsi; 1869 rc = 0; 1870 } 1871 1872 return rc; 1873 } 1874 1875 int dso__load(struct dso *dso, struct map *map) 1876 { 1877 char *name; 1878 int ret = -1; 1879 u_int i; 1880 struct machine *machine = NULL; 1881 char *root_dir = (char *) ""; 1882 int ss_pos = 0; 1883 struct symsrc ss_[2]; 1884 struct symsrc *syms_ss = NULL, *runtime_ss = NULL; 1885 bool kmod; 1886 bool perfmap; 1887 struct build_id bid; 1888 struct nscookie nsc; 1889 char newmapname[PATH_MAX]; 1890 const char *map_path = dso->long_name; 1891 1892 mutex_lock(&dso->lock); 1893 perfmap = strncmp(dso->name, "/tmp/perf-", 10) == 0; 1894 if (perfmap) { 1895 if (dso->nsinfo && (dso__find_perf_map(newmapname, 1896 sizeof(newmapname), &dso->nsinfo) == 0)) { 1897 map_path = newmapname; 1898 } 1899 } 1900 1901 nsinfo__mountns_enter(dso->nsinfo, &nsc); 1902 1903 /* check again under the dso->lock */ 1904 if (dso__loaded(dso)) { 1905 ret = 1; 1906 goto out; 1907 } 1908 1909 kmod = dso->symtab_type == DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE || 1910 dso->symtab_type == DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP || 1911 dso->symtab_type == DSO_BINARY_TYPE__GUEST_KMODULE || 1912 dso->symtab_type == DSO_BINARY_TYPE__GUEST_KMODULE_COMP; 1913 1914 if (dso->kernel && !kmod) { 1915 if (dso->kernel == DSO_SPACE__KERNEL) 1916 ret = dso__load_kernel_sym(dso, map); 1917 else if (dso->kernel == DSO_SPACE__KERNEL_GUEST) 1918 ret = dso__load_guest_kernel_sym(dso, map); 1919 1920 machine = maps__machine(map__kmaps(map)); 1921 if (machine__is(machine, "x86_64")) 1922 machine__map_x86_64_entry_trampolines(machine, dso); 1923 goto out; 1924 } 1925 1926 dso->adjust_symbols = 0; 1927 1928 if (perfmap) { 1929 ret = dso__load_perf_map(map_path, dso); 1930 dso->symtab_type = ret > 0 ? DSO_BINARY_TYPE__JAVA_JIT : 1931 DSO_BINARY_TYPE__NOT_FOUND; 1932 goto out; 1933 } 1934 1935 if (machine) 1936 root_dir = machine->root_dir; 1937 1938 name = malloc(PATH_MAX); 1939 if (!name) 1940 goto out; 1941 1942 /* 1943 * Read the build id if possible. This is required for 1944 * DSO_BINARY_TYPE__BUILDID_DEBUGINFO to work 1945 */ 1946 if (!dso->has_build_id && 1947 is_regular_file(dso->long_name)) { 1948 __symbol__join_symfs(name, PATH_MAX, dso->long_name); 1949 if (filename__read_build_id(name, &bid) > 0) 1950 dso__set_build_id(dso, &bid); 1951 } 1952 1953 /* 1954 * Iterate over candidate debug images. 1955 * Keep track of "interesting" ones (those which have a symtab, dynsym, 1956 * and/or opd section) for processing. 1957 */ 1958 for (i = 0; i < DSO_BINARY_TYPE__SYMTAB_CNT; i++) { 1959 struct symsrc *ss = &ss_[ss_pos]; 1960 bool next_slot = false; 1961 bool is_reg; 1962 bool nsexit; 1963 int bfdrc = -1; 1964 int sirc = -1; 1965 1966 enum dso_binary_type symtab_type = binary_type_symtab[i]; 1967 1968 nsexit = (symtab_type == DSO_BINARY_TYPE__BUILD_ID_CACHE || 1969 symtab_type == DSO_BINARY_TYPE__BUILD_ID_CACHE_DEBUGINFO); 1970 1971 if (!dso__is_compatible_symtab_type(dso, kmod, symtab_type)) 1972 continue; 1973 1974 if (dso__read_binary_type_filename(dso, symtab_type, 1975 root_dir, name, PATH_MAX)) 1976 continue; 1977 1978 if (nsexit) 1979 nsinfo__mountns_exit(&nsc); 1980 1981 is_reg = is_regular_file(name); 1982 if (!is_reg && errno == ENOENT && dso->nsinfo) { 1983 char *new_name = dso__filename_with_chroot(dso, name); 1984 if (new_name) { 1985 is_reg = is_regular_file(new_name); 1986 strlcpy(name, new_name, PATH_MAX); 1987 free(new_name); 1988 } 1989 } 1990 1991 #ifdef HAVE_LIBBFD_SUPPORT 1992 if (is_reg) 1993 bfdrc = dso__load_bfd_symbols(dso, name); 1994 #endif 1995 if (is_reg && bfdrc < 0) 1996 sirc = symsrc__init(ss, dso, name, symtab_type); 1997 1998 if (nsexit) 1999 nsinfo__mountns_enter(dso->nsinfo, &nsc); 2000 2001 if (bfdrc == 0) { 2002 ret = 0; 2003 break; 2004 } 2005 2006 if (!is_reg || sirc < 0) 2007 continue; 2008 2009 if (!syms_ss && symsrc__has_symtab(ss)) { 2010 syms_ss = ss; 2011 next_slot = true; 2012 if (!dso->symsrc_filename) 2013 dso->symsrc_filename = strdup(name); 2014 } 2015 2016 if (!runtime_ss && symsrc__possibly_runtime(ss)) { 2017 runtime_ss = ss; 2018 next_slot = true; 2019 } 2020 2021 if (next_slot) { 2022 ss_pos++; 2023 2024 if (syms_ss && runtime_ss) 2025 break; 2026 } else { 2027 symsrc__destroy(ss); 2028 } 2029 2030 } 2031 2032 if (!runtime_ss && !syms_ss) 2033 goto out_free; 2034 2035 if (runtime_ss && !syms_ss) { 2036 syms_ss = runtime_ss; 2037 } 2038 2039 /* We'll have to hope for the best */ 2040 if (!runtime_ss && syms_ss) 2041 runtime_ss = syms_ss; 2042 2043 if (syms_ss) 2044 ret = dso__load_sym(dso, map, syms_ss, runtime_ss, kmod); 2045 else 2046 ret = -1; 2047 2048 if (ret > 0) { 2049 int nr_plt; 2050 2051 nr_plt = dso__synthesize_plt_symbols(dso, runtime_ss); 2052 if (nr_plt > 0) 2053 ret += nr_plt; 2054 } 2055 2056 for (; ss_pos > 0; ss_pos--) 2057 symsrc__destroy(&ss_[ss_pos - 1]); 2058 out_free: 2059 free(name); 2060 if (ret < 0 && strstr(dso->name, " (deleted)") != NULL) 2061 ret = 0; 2062 out: 2063 dso__set_loaded(dso); 2064 mutex_unlock(&dso->lock); 2065 nsinfo__mountns_exit(&nsc); 2066 2067 return ret; 2068 } 2069 2070 static int map__strcmp(const void *a, const void *b) 2071 { 2072 const struct map *map_a = *(const struct map **)a; 2073 const struct map *map_b = *(const struct map **)b; 2074 const struct dso *dso_a = map__dso(map_a); 2075 const struct dso *dso_b = map__dso(map_b); 2076 int ret = strcmp(dso_a->short_name, dso_b->short_name); 2077 2078 if (ret == 0 && map_a != map_b) { 2079 /* 2080 * Ensure distinct but name equal maps have an order in part to 2081 * aid reference counting. 2082 */ 2083 ret = (int)map__start(map_a) - (int)map__start(map_b); 2084 if (ret == 0) 2085 ret = (int)((intptr_t)map_a - (intptr_t)map_b); 2086 } 2087 2088 return ret; 2089 } 2090 2091 static int map__strcmp_name(const void *name, const void *b) 2092 { 2093 const struct dso *dso = map__dso(*(const struct map **)b); 2094 2095 return strcmp(name, dso->short_name); 2096 } 2097 2098 void __maps__sort_by_name(struct maps *maps) 2099 { 2100 qsort(maps__maps_by_name(maps), maps__nr_maps(maps), sizeof(struct map *), map__strcmp); 2101 } 2102 2103 static int map__groups__sort_by_name_from_rbtree(struct maps *maps) 2104 { 2105 struct map_rb_node *rb_node; 2106 struct map **maps_by_name = realloc(maps__maps_by_name(maps), 2107 maps__nr_maps(maps) * sizeof(struct map *)); 2108 int i = 0; 2109 2110 if (maps_by_name == NULL) 2111 return -1; 2112 2113 up_read(maps__lock(maps)); 2114 down_write(maps__lock(maps)); 2115 2116 RC_CHK_ACCESS(maps)->maps_by_name = maps_by_name; 2117 RC_CHK_ACCESS(maps)->nr_maps_allocated = maps__nr_maps(maps); 2118 2119 maps__for_each_entry(maps, rb_node) 2120 maps_by_name[i++] = map__get(rb_node->map); 2121 2122 __maps__sort_by_name(maps); 2123 2124 up_write(maps__lock(maps)); 2125 down_read(maps__lock(maps)); 2126 2127 return 0; 2128 } 2129 2130 static struct map *__maps__find_by_name(struct maps *maps, const char *name) 2131 { 2132 struct map **mapp; 2133 2134 if (maps__maps_by_name(maps) == NULL && 2135 map__groups__sort_by_name_from_rbtree(maps)) 2136 return NULL; 2137 2138 mapp = bsearch(name, maps__maps_by_name(maps), maps__nr_maps(maps), 2139 sizeof(*mapp), map__strcmp_name); 2140 if (mapp) 2141 return *mapp; 2142 return NULL; 2143 } 2144 2145 struct map *maps__find_by_name(struct maps *maps, const char *name) 2146 { 2147 struct map_rb_node *rb_node; 2148 struct map *map; 2149 2150 down_read(maps__lock(maps)); 2151 2152 2153 if (RC_CHK_ACCESS(maps)->last_search_by_name) { 2154 const struct dso *dso = map__dso(RC_CHK_ACCESS(maps)->last_search_by_name); 2155 2156 if (strcmp(dso->short_name, name) == 0) { 2157 map = RC_CHK_ACCESS(maps)->last_search_by_name; 2158 goto out_unlock; 2159 } 2160 } 2161 /* 2162 * If we have maps->maps_by_name, then the name isn't in the rbtree, 2163 * as maps->maps_by_name mirrors the rbtree when lookups by name are 2164 * made. 2165 */ 2166 map = __maps__find_by_name(maps, name); 2167 if (map || maps__maps_by_name(maps) != NULL) 2168 goto out_unlock; 2169 2170 /* Fallback to traversing the rbtree... */ 2171 maps__for_each_entry(maps, rb_node) { 2172 struct dso *dso; 2173 2174 map = rb_node->map; 2175 dso = map__dso(map); 2176 if (strcmp(dso->short_name, name) == 0) { 2177 RC_CHK_ACCESS(maps)->last_search_by_name = map; 2178 goto out_unlock; 2179 } 2180 } 2181 map = NULL; 2182 2183 out_unlock: 2184 up_read(maps__lock(maps)); 2185 return map; 2186 } 2187 2188 int dso__load_vmlinux(struct dso *dso, struct map *map, 2189 const char *vmlinux, bool vmlinux_allocated) 2190 { 2191 int err = -1; 2192 struct symsrc ss; 2193 char symfs_vmlinux[PATH_MAX]; 2194 enum dso_binary_type symtab_type; 2195 2196 if (vmlinux[0] == '/') 2197 snprintf(symfs_vmlinux, sizeof(symfs_vmlinux), "%s", vmlinux); 2198 else 2199 symbol__join_symfs(symfs_vmlinux, vmlinux); 2200 2201 if (dso->kernel == DSO_SPACE__KERNEL_GUEST) 2202 symtab_type = DSO_BINARY_TYPE__GUEST_VMLINUX; 2203 else 2204 symtab_type = DSO_BINARY_TYPE__VMLINUX; 2205 2206 if (symsrc__init(&ss, dso, symfs_vmlinux, symtab_type)) 2207 return -1; 2208 2209 /* 2210 * dso__load_sym() may copy 'dso' which will result in the copies having 2211 * an incorrect long name unless we set it here first. 2212 */ 2213 dso__set_long_name(dso, vmlinux, vmlinux_allocated); 2214 if (dso->kernel == DSO_SPACE__KERNEL_GUEST) 2215 dso->binary_type = DSO_BINARY_TYPE__GUEST_VMLINUX; 2216 else 2217 dso->binary_type = DSO_BINARY_TYPE__VMLINUX; 2218 2219 err = dso__load_sym(dso, map, &ss, &ss, 0); 2220 symsrc__destroy(&ss); 2221 2222 if (err > 0) { 2223 dso__set_loaded(dso); 2224 pr_debug("Using %s for symbols\n", symfs_vmlinux); 2225 } 2226 2227 return err; 2228 } 2229 2230 int dso__load_vmlinux_path(struct dso *dso, struct map *map) 2231 { 2232 int i, err = 0; 2233 char *filename = NULL; 2234 2235 pr_debug("Looking at the vmlinux_path (%d entries long)\n", 2236 vmlinux_path__nr_entries + 1); 2237 2238 for (i = 0; i < vmlinux_path__nr_entries; ++i) { 2239 err = dso__load_vmlinux(dso, map, vmlinux_path[i], false); 2240 if (err > 0) 2241 goto out; 2242 } 2243 2244 if (!symbol_conf.ignore_vmlinux_buildid) 2245 filename = dso__build_id_filename(dso, NULL, 0, false); 2246 if (filename != NULL) { 2247 err = dso__load_vmlinux(dso, map, filename, true); 2248 if (err > 0) 2249 goto out; 2250 free(filename); 2251 } 2252 out: 2253 return err; 2254 } 2255 2256 static bool visible_dir_filter(const char *name, struct dirent *d) 2257 { 2258 if (d->d_type != DT_DIR) 2259 return false; 2260 return lsdir_no_dot_filter(name, d); 2261 } 2262 2263 static int find_matching_kcore(struct map *map, char *dir, size_t dir_sz) 2264 { 2265 char kallsyms_filename[PATH_MAX]; 2266 int ret = -1; 2267 struct strlist *dirs; 2268 struct str_node *nd; 2269 2270 dirs = lsdir(dir, visible_dir_filter); 2271 if (!dirs) 2272 return -1; 2273 2274 strlist__for_each_entry(nd, dirs) { 2275 scnprintf(kallsyms_filename, sizeof(kallsyms_filename), 2276 "%s/%s/kallsyms", dir, nd->s); 2277 if (!validate_kcore_addresses(kallsyms_filename, map)) { 2278 strlcpy(dir, kallsyms_filename, dir_sz); 2279 ret = 0; 2280 break; 2281 } 2282 } 2283 2284 strlist__delete(dirs); 2285 2286 return ret; 2287 } 2288 2289 /* 2290 * Use open(O_RDONLY) to check readability directly instead of access(R_OK) 2291 * since access(R_OK) only checks with real UID/GID but open() use effective 2292 * UID/GID and actual capabilities (e.g. /proc/kcore requires CAP_SYS_RAWIO). 2293 */ 2294 static bool filename__readable(const char *file) 2295 { 2296 int fd = open(file, O_RDONLY); 2297 if (fd < 0) 2298 return false; 2299 close(fd); 2300 return true; 2301 } 2302 2303 static char *dso__find_kallsyms(struct dso *dso, struct map *map) 2304 { 2305 struct build_id bid; 2306 char sbuild_id[SBUILD_ID_SIZE]; 2307 bool is_host = false; 2308 char path[PATH_MAX]; 2309 2310 if (!dso->has_build_id) { 2311 /* 2312 * Last resort, if we don't have a build-id and couldn't find 2313 * any vmlinux file, try the running kernel kallsyms table. 2314 */ 2315 goto proc_kallsyms; 2316 } 2317 2318 if (sysfs__read_build_id("/sys/kernel/notes", &bid) == 0) 2319 is_host = dso__build_id_equal(dso, &bid); 2320 2321 /* Try a fast path for /proc/kallsyms if possible */ 2322 if (is_host) { 2323 /* 2324 * Do not check the build-id cache, unless we know we cannot use 2325 * /proc/kcore or module maps don't match to /proc/kallsyms. 2326 * To check readability of /proc/kcore, do not use access(R_OK) 2327 * since /proc/kcore requires CAP_SYS_RAWIO to read and access 2328 * can't check it. 2329 */ 2330 if (filename__readable("/proc/kcore") && 2331 !validate_kcore_addresses("/proc/kallsyms", map)) 2332 goto proc_kallsyms; 2333 } 2334 2335 build_id__sprintf(&dso->bid, sbuild_id); 2336 2337 /* Find kallsyms in build-id cache with kcore */ 2338 scnprintf(path, sizeof(path), "%s/%s/%s", 2339 buildid_dir, DSO__NAME_KCORE, sbuild_id); 2340 2341 if (!find_matching_kcore(map, path, sizeof(path))) 2342 return strdup(path); 2343 2344 /* Use current /proc/kallsyms if possible */ 2345 if (is_host) { 2346 proc_kallsyms: 2347 return strdup("/proc/kallsyms"); 2348 } 2349 2350 /* Finally, find a cache of kallsyms */ 2351 if (!build_id_cache__kallsyms_path(sbuild_id, path, sizeof(path))) { 2352 pr_err("No kallsyms or vmlinux with build-id %s was found\n", 2353 sbuild_id); 2354 return NULL; 2355 } 2356 2357 return strdup(path); 2358 } 2359 2360 static int dso__load_kernel_sym(struct dso *dso, struct map *map) 2361 { 2362 int err; 2363 const char *kallsyms_filename = NULL; 2364 char *kallsyms_allocated_filename = NULL; 2365 char *filename = NULL; 2366 2367 /* 2368 * Step 1: if the user specified a kallsyms or vmlinux filename, use 2369 * it and only it, reporting errors to the user if it cannot be used. 2370 * 2371 * For instance, try to analyse an ARM perf.data file _without_ a 2372 * build-id, or if the user specifies the wrong path to the right 2373 * vmlinux file, obviously we can't fallback to another vmlinux (a 2374 * x86_86 one, on the machine where analysis is being performed, say), 2375 * or worse, /proc/kallsyms. 2376 * 2377 * If the specified file _has_ a build-id and there is a build-id 2378 * section in the perf.data file, we will still do the expected 2379 * validation in dso__load_vmlinux and will bail out if they don't 2380 * match. 2381 */ 2382 if (symbol_conf.kallsyms_name != NULL) { 2383 kallsyms_filename = symbol_conf.kallsyms_name; 2384 goto do_kallsyms; 2385 } 2386 2387 if (!symbol_conf.ignore_vmlinux && symbol_conf.vmlinux_name != NULL) { 2388 return dso__load_vmlinux(dso, map, symbol_conf.vmlinux_name, false); 2389 } 2390 2391 /* 2392 * Before checking on common vmlinux locations, check if it's 2393 * stored as standard build id binary (not kallsyms) under 2394 * .debug cache. 2395 */ 2396 if (!symbol_conf.ignore_vmlinux_buildid) 2397 filename = __dso__build_id_filename(dso, NULL, 0, false, false); 2398 if (filename != NULL) { 2399 err = dso__load_vmlinux(dso, map, filename, true); 2400 if (err > 0) 2401 return err; 2402 free(filename); 2403 } 2404 2405 if (!symbol_conf.ignore_vmlinux && vmlinux_path != NULL) { 2406 err = dso__load_vmlinux_path(dso, map); 2407 if (err > 0) 2408 return err; 2409 } 2410 2411 /* do not try local files if a symfs was given */ 2412 if (symbol_conf.symfs[0] != 0) 2413 return -1; 2414 2415 kallsyms_allocated_filename = dso__find_kallsyms(dso, map); 2416 if (!kallsyms_allocated_filename) 2417 return -1; 2418 2419 kallsyms_filename = kallsyms_allocated_filename; 2420 2421 do_kallsyms: 2422 err = dso__load_kallsyms(dso, kallsyms_filename, map); 2423 if (err > 0) 2424 pr_debug("Using %s for symbols\n", kallsyms_filename); 2425 free(kallsyms_allocated_filename); 2426 2427 if (err > 0 && !dso__is_kcore(dso)) { 2428 dso->binary_type = DSO_BINARY_TYPE__KALLSYMS; 2429 dso__set_long_name(dso, DSO__NAME_KALLSYMS, false); 2430 map__fixup_start(map); 2431 map__fixup_end(map); 2432 } 2433 2434 return err; 2435 } 2436 2437 static int dso__load_guest_kernel_sym(struct dso *dso, struct map *map) 2438 { 2439 int err; 2440 const char *kallsyms_filename; 2441 struct machine *machine = maps__machine(map__kmaps(map)); 2442 char path[PATH_MAX]; 2443 2444 if (machine->kallsyms_filename) { 2445 kallsyms_filename = machine->kallsyms_filename; 2446 } else if (machine__is_default_guest(machine)) { 2447 /* 2448 * if the user specified a vmlinux filename, use it and only 2449 * it, reporting errors to the user if it cannot be used. 2450 * Or use file guest_kallsyms inputted by user on commandline 2451 */ 2452 if (symbol_conf.default_guest_vmlinux_name != NULL) { 2453 err = dso__load_vmlinux(dso, map, 2454 symbol_conf.default_guest_vmlinux_name, 2455 false); 2456 return err; 2457 } 2458 2459 kallsyms_filename = symbol_conf.default_guest_kallsyms; 2460 if (!kallsyms_filename) 2461 return -1; 2462 } else { 2463 sprintf(path, "%s/proc/kallsyms", machine->root_dir); 2464 kallsyms_filename = path; 2465 } 2466 2467 err = dso__load_kallsyms(dso, kallsyms_filename, map); 2468 if (err > 0) 2469 pr_debug("Using %s for symbols\n", kallsyms_filename); 2470 if (err > 0 && !dso__is_kcore(dso)) { 2471 dso->binary_type = DSO_BINARY_TYPE__GUEST_KALLSYMS; 2472 dso__set_long_name(dso, machine->mmap_name, false); 2473 map__fixup_start(map); 2474 map__fixup_end(map); 2475 } 2476 2477 return err; 2478 } 2479 2480 static void vmlinux_path__exit(void) 2481 { 2482 while (--vmlinux_path__nr_entries >= 0) 2483 zfree(&vmlinux_path[vmlinux_path__nr_entries]); 2484 vmlinux_path__nr_entries = 0; 2485 2486 zfree(&vmlinux_path); 2487 } 2488 2489 static const char * const vmlinux_paths[] = { 2490 "vmlinux", 2491 "/boot/vmlinux" 2492 }; 2493 2494 static const char * const vmlinux_paths_upd[] = { 2495 "/boot/vmlinux-%s", 2496 "/usr/lib/debug/boot/vmlinux-%s", 2497 "/lib/modules/%s/build/vmlinux", 2498 "/usr/lib/debug/lib/modules/%s/vmlinux", 2499 "/usr/lib/debug/boot/vmlinux-%s.debug" 2500 }; 2501 2502 static int vmlinux_path__add(const char *new_entry) 2503 { 2504 vmlinux_path[vmlinux_path__nr_entries] = strdup(new_entry); 2505 if (vmlinux_path[vmlinux_path__nr_entries] == NULL) 2506 return -1; 2507 ++vmlinux_path__nr_entries; 2508 2509 return 0; 2510 } 2511 2512 static int vmlinux_path__init(struct perf_env *env) 2513 { 2514 struct utsname uts; 2515 char bf[PATH_MAX]; 2516 char *kernel_version; 2517 unsigned int i; 2518 2519 vmlinux_path = malloc(sizeof(char *) * (ARRAY_SIZE(vmlinux_paths) + 2520 ARRAY_SIZE(vmlinux_paths_upd))); 2521 if (vmlinux_path == NULL) 2522 return -1; 2523 2524 for (i = 0; i < ARRAY_SIZE(vmlinux_paths); i++) 2525 if (vmlinux_path__add(vmlinux_paths[i]) < 0) 2526 goto out_fail; 2527 2528 /* only try kernel version if no symfs was given */ 2529 if (symbol_conf.symfs[0] != 0) 2530 return 0; 2531 2532 if (env) { 2533 kernel_version = env->os_release; 2534 } else { 2535 if (uname(&uts) < 0) 2536 goto out_fail; 2537 2538 kernel_version = uts.release; 2539 } 2540 2541 for (i = 0; i < ARRAY_SIZE(vmlinux_paths_upd); i++) { 2542 snprintf(bf, sizeof(bf), vmlinux_paths_upd[i], kernel_version); 2543 if (vmlinux_path__add(bf) < 0) 2544 goto out_fail; 2545 } 2546 2547 return 0; 2548 2549 out_fail: 2550 vmlinux_path__exit(); 2551 return -1; 2552 } 2553 2554 int setup_list(struct strlist **list, const char *list_str, 2555 const char *list_name) 2556 { 2557 if (list_str == NULL) 2558 return 0; 2559 2560 *list = strlist__new(list_str, NULL); 2561 if (!*list) { 2562 pr_err("problems parsing %s list\n", list_name); 2563 return -1; 2564 } 2565 2566 symbol_conf.has_filter = true; 2567 return 0; 2568 } 2569 2570 int setup_intlist(struct intlist **list, const char *list_str, 2571 const char *list_name) 2572 { 2573 if (list_str == NULL) 2574 return 0; 2575 2576 *list = intlist__new(list_str); 2577 if (!*list) { 2578 pr_err("problems parsing %s list\n", list_name); 2579 return -1; 2580 } 2581 return 0; 2582 } 2583 2584 static int setup_addrlist(struct intlist **addr_list, struct strlist *sym_list) 2585 { 2586 struct str_node *pos, *tmp; 2587 unsigned long val; 2588 char *sep; 2589 const char *end; 2590 int i = 0, err; 2591 2592 *addr_list = intlist__new(NULL); 2593 if (!*addr_list) 2594 return -1; 2595 2596 strlist__for_each_entry_safe(pos, tmp, sym_list) { 2597 errno = 0; 2598 val = strtoul(pos->s, &sep, 16); 2599 if (errno || (sep == pos->s)) 2600 continue; 2601 2602 if (*sep != '\0') { 2603 end = pos->s + strlen(pos->s) - 1; 2604 while (end >= sep && isspace(*end)) 2605 end--; 2606 2607 if (end >= sep) 2608 continue; 2609 } 2610 2611 err = intlist__add(*addr_list, val); 2612 if (err) 2613 break; 2614 2615 strlist__remove(sym_list, pos); 2616 i++; 2617 } 2618 2619 if (i == 0) { 2620 intlist__delete(*addr_list); 2621 *addr_list = NULL; 2622 } 2623 2624 return 0; 2625 } 2626 2627 static bool symbol__read_kptr_restrict(void) 2628 { 2629 bool value = false; 2630 FILE *fp = fopen("/proc/sys/kernel/kptr_restrict", "r"); 2631 2632 if (fp != NULL) { 2633 char line[8]; 2634 2635 if (fgets(line, sizeof(line), fp) != NULL) 2636 value = perf_cap__capable(CAP_SYSLOG) ? 2637 (atoi(line) >= 2) : 2638 (atoi(line) != 0); 2639 2640 fclose(fp); 2641 } 2642 2643 /* Per kernel/kallsyms.c: 2644 * we also restrict when perf_event_paranoid > 1 w/o CAP_SYSLOG 2645 */ 2646 if (perf_event_paranoid() > 1 && !perf_cap__capable(CAP_SYSLOG)) 2647 value = true; 2648 2649 return value; 2650 } 2651 2652 int symbol__annotation_init(void) 2653 { 2654 if (symbol_conf.init_annotation) 2655 return 0; 2656 2657 if (symbol_conf.initialized) { 2658 pr_err("Annotation needs to be init before symbol__init()\n"); 2659 return -1; 2660 } 2661 2662 symbol_conf.priv_size += sizeof(struct annotation); 2663 symbol_conf.init_annotation = true; 2664 return 0; 2665 } 2666 2667 int symbol__init(struct perf_env *env) 2668 { 2669 const char *symfs; 2670 2671 if (symbol_conf.initialized) 2672 return 0; 2673 2674 symbol_conf.priv_size = PERF_ALIGN(symbol_conf.priv_size, sizeof(u64)); 2675 2676 symbol__elf_init(); 2677 2678 if (symbol_conf.try_vmlinux_path && vmlinux_path__init(env) < 0) 2679 return -1; 2680 2681 if (symbol_conf.field_sep && *symbol_conf.field_sep == '.') { 2682 pr_err("'.' is the only non valid --field-separator argument\n"); 2683 return -1; 2684 } 2685 2686 if (setup_list(&symbol_conf.dso_list, 2687 symbol_conf.dso_list_str, "dso") < 0) 2688 return -1; 2689 2690 if (setup_list(&symbol_conf.comm_list, 2691 symbol_conf.comm_list_str, "comm") < 0) 2692 goto out_free_dso_list; 2693 2694 if (setup_intlist(&symbol_conf.pid_list, 2695 symbol_conf.pid_list_str, "pid") < 0) 2696 goto out_free_comm_list; 2697 2698 if (setup_intlist(&symbol_conf.tid_list, 2699 symbol_conf.tid_list_str, "tid") < 0) 2700 goto out_free_pid_list; 2701 2702 if (setup_list(&symbol_conf.sym_list, 2703 symbol_conf.sym_list_str, "symbol") < 0) 2704 goto out_free_tid_list; 2705 2706 if (symbol_conf.sym_list && 2707 setup_addrlist(&symbol_conf.addr_list, symbol_conf.sym_list) < 0) 2708 goto out_free_sym_list; 2709 2710 if (setup_list(&symbol_conf.bt_stop_list, 2711 symbol_conf.bt_stop_list_str, "symbol") < 0) 2712 goto out_free_sym_list; 2713 2714 /* 2715 * A path to symbols of "/" is identical to "" 2716 * reset here for simplicity. 2717 */ 2718 symfs = realpath(symbol_conf.symfs, NULL); 2719 if (symfs == NULL) 2720 symfs = symbol_conf.symfs; 2721 if (strcmp(symfs, "/") == 0) 2722 symbol_conf.symfs = ""; 2723 if (symfs != symbol_conf.symfs) 2724 free((void *)symfs); 2725 2726 symbol_conf.kptr_restrict = symbol__read_kptr_restrict(); 2727 2728 symbol_conf.initialized = true; 2729 return 0; 2730 2731 out_free_sym_list: 2732 strlist__delete(symbol_conf.sym_list); 2733 intlist__delete(symbol_conf.addr_list); 2734 out_free_tid_list: 2735 intlist__delete(symbol_conf.tid_list); 2736 out_free_pid_list: 2737 intlist__delete(symbol_conf.pid_list); 2738 out_free_comm_list: 2739 strlist__delete(symbol_conf.comm_list); 2740 out_free_dso_list: 2741 strlist__delete(symbol_conf.dso_list); 2742 return -1; 2743 } 2744 2745 void symbol__exit(void) 2746 { 2747 if (!symbol_conf.initialized) 2748 return; 2749 strlist__delete(symbol_conf.bt_stop_list); 2750 strlist__delete(symbol_conf.sym_list); 2751 strlist__delete(symbol_conf.dso_list); 2752 strlist__delete(symbol_conf.comm_list); 2753 intlist__delete(symbol_conf.tid_list); 2754 intlist__delete(symbol_conf.pid_list); 2755 intlist__delete(symbol_conf.addr_list); 2756 vmlinux_path__exit(); 2757 symbol_conf.sym_list = symbol_conf.dso_list = symbol_conf.comm_list = NULL; 2758 symbol_conf.bt_stop_list = NULL; 2759 symbol_conf.initialized = false; 2760 } 2761 2762 int symbol__config_symfs(const struct option *opt __maybe_unused, 2763 const char *dir, int unset __maybe_unused) 2764 { 2765 char *bf = NULL; 2766 int ret; 2767 2768 symbol_conf.symfs = strdup(dir); 2769 if (symbol_conf.symfs == NULL) 2770 return -ENOMEM; 2771 2772 /* skip the locally configured cache if a symfs is given, and 2773 * config buildid dir to symfs/.debug 2774 */ 2775 ret = asprintf(&bf, "%s/%s", dir, ".debug"); 2776 if (ret < 0) 2777 return -ENOMEM; 2778 2779 set_buildid_dir(bf); 2780 2781 free(bf); 2782 return 0; 2783 } 2784 2785 struct mem_info *mem_info__get(struct mem_info *mi) 2786 { 2787 if (mi) 2788 refcount_inc(&mi->refcnt); 2789 return mi; 2790 } 2791 2792 void mem_info__put(struct mem_info *mi) 2793 { 2794 if (mi && refcount_dec_and_test(&mi->refcnt)) { 2795 addr_map_symbol__exit(&mi->iaddr); 2796 addr_map_symbol__exit(&mi->daddr); 2797 free(mi); 2798 } 2799 } 2800 2801 struct mem_info *mem_info__new(void) 2802 { 2803 struct mem_info *mi = zalloc(sizeof(*mi)); 2804 2805 if (mi) 2806 refcount_set(&mi->refcnt, 1); 2807 return mi; 2808 } 2809 2810 /* 2811 * Checks that user supplied symbol kernel files are accessible because 2812 * the default mechanism for accessing elf files fails silently. i.e. if 2813 * debug syms for a build ID aren't found perf carries on normally. When 2814 * they are user supplied we should assume that the user doesn't want to 2815 * silently fail. 2816 */ 2817 int symbol__validate_sym_arguments(void) 2818 { 2819 if (symbol_conf.vmlinux_name && 2820 access(symbol_conf.vmlinux_name, R_OK)) { 2821 pr_err("Invalid file: %s\n", symbol_conf.vmlinux_name); 2822 return -EINVAL; 2823 } 2824 if (symbol_conf.kallsyms_name && 2825 access(symbol_conf.kallsyms_name, R_OK)) { 2826 pr_err("Invalid file: %s\n", symbol_conf.kallsyms_name); 2827 return -EINVAL; 2828 } 2829 return 0; 2830 } 2831