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 "mem-info.h" 31 #include "symsrc.h" 32 #include "strlist.h" 33 #include "intlist.h" 34 #include "namespaces.h" 35 #include "header.h" 36 #include "path.h" 37 #include <linux/ctype.h> 38 #include <linux/zalloc.h> 39 40 #include <elf.h> 41 #include <limits.h> 42 #include <symbol/kallsyms.h> 43 #include <sys/utsname.h> 44 45 static int dso__load_kernel_sym(struct dso *dso, struct map *map); 46 static int dso__load_guest_kernel_sym(struct dso *dso, struct map *map); 47 static bool symbol__is_idle(const char *name); 48 49 int vmlinux_path__nr_entries; 50 char **vmlinux_path; 51 52 struct symbol_conf symbol_conf = { 53 .nanosecs = false, 54 .use_modules = true, 55 .try_vmlinux_path = true, 56 .demangle = true, 57 .demangle_kernel = false, 58 .cumulate_callchain = true, 59 .time_quantum = 100 * NSEC_PER_MSEC, /* 100ms */ 60 .show_hist_headers = true, 61 .symfs = "", 62 .event_group = true, 63 .inline_name = true, 64 .res_sample = 0, 65 }; 66 67 struct map_list_node { 68 struct list_head node; 69 struct map *map; 70 }; 71 72 static struct map_list_node *map_list_node__new(void) 73 { 74 return malloc(sizeof(struct map_list_node)); 75 } 76 77 static enum dso_binary_type binary_type_symtab[] = { 78 DSO_BINARY_TYPE__KALLSYMS, 79 DSO_BINARY_TYPE__GUEST_KALLSYMS, 80 DSO_BINARY_TYPE__JAVA_JIT, 81 DSO_BINARY_TYPE__DEBUGLINK, 82 DSO_BINARY_TYPE__BUILD_ID_CACHE, 83 DSO_BINARY_TYPE__BUILD_ID_CACHE_DEBUGINFO, 84 DSO_BINARY_TYPE__FEDORA_DEBUGINFO, 85 DSO_BINARY_TYPE__UBUNTU_DEBUGINFO, 86 DSO_BINARY_TYPE__BUILDID_DEBUGINFO, 87 DSO_BINARY_TYPE__SYSTEM_PATH_DSO, 88 DSO_BINARY_TYPE__GUEST_KMODULE, 89 DSO_BINARY_TYPE__GUEST_KMODULE_COMP, 90 DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE, 91 DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP, 92 DSO_BINARY_TYPE__OPENEMBEDDED_DEBUGINFO, 93 DSO_BINARY_TYPE__MIXEDUP_UBUNTU_DEBUGINFO, 94 DSO_BINARY_TYPE__NOT_FOUND, 95 }; 96 97 #define DSO_BINARY_TYPE__SYMTAB_CNT ARRAY_SIZE(binary_type_symtab) 98 99 static bool symbol_type__filter(char symbol_type) 100 { 101 symbol_type = toupper(symbol_type); 102 return symbol_type == 'T' || symbol_type == 'W' || symbol_type == 'D' || symbol_type == 'B'; 103 } 104 105 static int prefix_underscores_count(const char *str) 106 { 107 const char *tail = str; 108 109 while (*tail == '_') 110 tail++; 111 112 return tail - str; 113 } 114 115 const char * __weak arch__normalize_symbol_name(const char *name) 116 { 117 return name; 118 } 119 120 int __weak arch__compare_symbol_names(const char *namea, const char *nameb) 121 { 122 return strcmp(namea, nameb); 123 } 124 125 int __weak arch__compare_symbol_names_n(const char *namea, const char *nameb, 126 unsigned int n) 127 { 128 return strncmp(namea, nameb, n); 129 } 130 131 int __weak arch__choose_best_symbol(struct symbol *syma, 132 struct symbol *symb __maybe_unused) 133 { 134 /* Avoid "SyS" kernel syscall aliases */ 135 if (strlen(syma->name) >= 3 && !strncmp(syma->name, "SyS", 3)) 136 return SYMBOL_B; 137 if (strlen(syma->name) >= 10 && !strncmp(syma->name, "compat_SyS", 10)) 138 return SYMBOL_B; 139 140 return SYMBOL_A; 141 } 142 143 static int choose_best_symbol(struct symbol *syma, struct symbol *symb) 144 { 145 s64 a; 146 s64 b; 147 size_t na, nb; 148 149 /* Prefer a symbol with non zero length */ 150 a = syma->end - syma->start; 151 b = symb->end - symb->start; 152 if ((b == 0) && (a > 0)) 153 return SYMBOL_A; 154 else if ((a == 0) && (b > 0)) 155 return SYMBOL_B; 156 157 if (syma->type != symb->type) { 158 if (syma->type == STT_NOTYPE) 159 return SYMBOL_B; 160 if (symb->type == STT_NOTYPE) 161 return SYMBOL_A; 162 } 163 164 /* Prefer a non weak symbol over a weak one */ 165 a = syma->binding == STB_WEAK; 166 b = symb->binding == STB_WEAK; 167 if (b && !a) 168 return SYMBOL_A; 169 if (a && !b) 170 return SYMBOL_B; 171 172 /* Prefer a global symbol over a non global one */ 173 a = syma->binding == STB_GLOBAL; 174 b = symb->binding == STB_GLOBAL; 175 if (a && !b) 176 return SYMBOL_A; 177 if (b && !a) 178 return SYMBOL_B; 179 180 /* Prefer a symbol with less underscores */ 181 a = prefix_underscores_count(syma->name); 182 b = prefix_underscores_count(symb->name); 183 if (b > a) 184 return SYMBOL_A; 185 else if (a > b) 186 return SYMBOL_B; 187 188 /* Choose the symbol with the longest name */ 189 na = strlen(syma->name); 190 nb = strlen(symb->name); 191 if (na > nb) 192 return SYMBOL_A; 193 else if (na < nb) 194 return SYMBOL_B; 195 196 return arch__choose_best_symbol(syma, symb); 197 } 198 199 void symbols__fixup_duplicate(struct rb_root_cached *symbols) 200 { 201 struct rb_node *nd; 202 struct symbol *curr, *next; 203 204 if (symbol_conf.allow_aliases) 205 return; 206 207 nd = rb_first_cached(symbols); 208 209 while (nd) { 210 curr = rb_entry(nd, struct symbol, rb_node); 211 again: 212 nd = rb_next(&curr->rb_node); 213 if (!nd) 214 break; 215 216 next = rb_entry(nd, struct symbol, rb_node); 217 if (curr->start != next->start) 218 continue; 219 220 if (choose_best_symbol(curr, next) == SYMBOL_A) { 221 if (next->type == STT_GNU_IFUNC) 222 curr->ifunc_alias = true; 223 rb_erase_cached(&next->rb_node, symbols); 224 symbol__delete(next); 225 goto again; 226 } else { 227 if (curr->type == STT_GNU_IFUNC) 228 next->ifunc_alias = true; 229 nd = rb_next(&curr->rb_node); 230 rb_erase_cached(&curr->rb_node, symbols); 231 symbol__delete(curr); 232 } 233 } 234 } 235 236 /* Update zero-sized symbols using the address of the next symbol */ 237 void symbols__fixup_end(struct rb_root_cached *symbols, bool is_kallsyms) 238 { 239 struct rb_node *nd, *prevnd = rb_first_cached(symbols); 240 struct symbol *curr, *prev; 241 242 if (prevnd == NULL) 243 return; 244 245 curr = rb_entry(prevnd, struct symbol, rb_node); 246 247 for (nd = rb_next(prevnd); nd; nd = rb_next(nd)) { 248 prev = curr; 249 curr = rb_entry(nd, struct symbol, rb_node); 250 251 /* 252 * On some architecture kernel text segment start is located at 253 * some low memory address, while modules are located at high 254 * memory addresses (or vice versa). The gap between end of 255 * kernel text segment and beginning of first module's text 256 * segment is very big. Therefore do not fill this gap and do 257 * not assign it to the kernel dso map (kallsyms). 258 * 259 * Also BPF code can be allocated separately from text segments 260 * and modules. So the last entry in a module should not fill 261 * the gap too. 262 * 263 * In kallsyms, it determines module symbols using '[' character 264 * like in: 265 * ffffffffc1937000 T hdmi_driver_init [snd_hda_codec_hdmi] 266 */ 267 if (prev->end == prev->start) { 268 const char *prev_mod; 269 const char *curr_mod; 270 271 if (!is_kallsyms) { 272 prev->end = curr->start; 273 continue; 274 } 275 276 prev_mod = strchr(prev->name, '['); 277 curr_mod = strchr(curr->name, '['); 278 279 /* Last kernel/module symbol mapped to end of page */ 280 if (!prev_mod != !curr_mod) 281 prev->end = roundup(prev->end + 4096, 4096); 282 /* Last symbol in the previous module */ 283 else if (prev_mod && strcmp(prev_mod, curr_mod)) 284 prev->end = roundup(prev->end + 4096, 4096); 285 else 286 prev->end = curr->start; 287 288 pr_debug4("%s sym:%s end:%#" PRIx64 "\n", 289 __func__, prev->name, prev->end); 290 } 291 } 292 293 /* Last entry */ 294 if (curr->end == curr->start) 295 curr->end = roundup(curr->start, 4096) + 4096; 296 } 297 298 struct symbol *symbol__new(u64 start, u64 len, u8 binding, u8 type, const char *name) 299 { 300 size_t namelen = strlen(name) + 1; 301 struct symbol *sym = calloc(1, (symbol_conf.priv_size + 302 sizeof(*sym) + namelen)); 303 if (sym == NULL) 304 return NULL; 305 306 if (symbol_conf.priv_size) { 307 if (symbol_conf.init_annotation) { 308 struct annotation *notes = (void *)sym; 309 annotation__init(notes); 310 } 311 sym = ((void *)sym) + symbol_conf.priv_size; 312 } 313 314 sym->start = start; 315 sym->end = len ? start + len : start; 316 sym->type = type; 317 sym->binding = binding; 318 sym->namelen = namelen - 1; 319 320 pr_debug4("%s: %s %#" PRIx64 "-%#" PRIx64 "\n", 321 __func__, name, start, sym->end); 322 memcpy(sym->name, name, namelen); 323 324 return sym; 325 } 326 327 void symbol__delete(struct symbol *sym) 328 { 329 if (symbol_conf.priv_size) { 330 if (symbol_conf.init_annotation) { 331 struct annotation *notes = symbol__annotation(sym); 332 333 annotation__exit(notes); 334 } 335 } 336 free(((void *)sym) - symbol_conf.priv_size); 337 } 338 339 void symbols__delete(struct rb_root_cached *symbols) 340 { 341 struct symbol *pos; 342 struct rb_node *next = rb_first_cached(symbols); 343 344 while (next) { 345 pos = rb_entry(next, struct symbol, rb_node); 346 next = rb_next(&pos->rb_node); 347 rb_erase_cached(&pos->rb_node, symbols); 348 symbol__delete(pos); 349 } 350 } 351 352 void __symbols__insert(struct rb_root_cached *symbols, 353 struct symbol *sym, bool kernel) 354 { 355 struct rb_node **p = &symbols->rb_root.rb_node; 356 struct rb_node *parent = NULL; 357 const u64 ip = sym->start; 358 struct symbol *s; 359 bool leftmost = true; 360 361 if (kernel) { 362 const char *name = sym->name; 363 /* 364 * ppc64 uses function descriptors and appends a '.' to the 365 * start of every instruction address. Remove it. 366 */ 367 if (name[0] == '.') 368 name++; 369 sym->idle = symbol__is_idle(name); 370 } 371 372 while (*p != NULL) { 373 parent = *p; 374 s = rb_entry(parent, struct symbol, rb_node); 375 if (ip < s->start) 376 p = &(*p)->rb_left; 377 else { 378 p = &(*p)->rb_right; 379 leftmost = false; 380 } 381 } 382 rb_link_node(&sym->rb_node, parent, p); 383 rb_insert_color_cached(&sym->rb_node, symbols, leftmost); 384 } 385 386 void symbols__insert(struct rb_root_cached *symbols, struct symbol *sym) 387 { 388 __symbols__insert(symbols, sym, false); 389 } 390 391 static struct symbol *symbols__find(struct rb_root_cached *symbols, u64 ip) 392 { 393 struct rb_node *n; 394 395 if (symbols == NULL) 396 return NULL; 397 398 n = symbols->rb_root.rb_node; 399 400 while (n) { 401 struct symbol *s = rb_entry(n, struct symbol, rb_node); 402 403 if (ip < s->start) 404 n = n->rb_left; 405 else if (ip > s->end || (ip == s->end && ip != s->start)) 406 n = n->rb_right; 407 else 408 return s; 409 } 410 411 return NULL; 412 } 413 414 static struct symbol *symbols__first(struct rb_root_cached *symbols) 415 { 416 struct rb_node *n = rb_first_cached(symbols); 417 418 if (n) 419 return rb_entry(n, struct symbol, rb_node); 420 421 return NULL; 422 } 423 424 static struct symbol *symbols__last(struct rb_root_cached *symbols) 425 { 426 struct rb_node *n = rb_last(&symbols->rb_root); 427 428 if (n) 429 return rb_entry(n, struct symbol, rb_node); 430 431 return NULL; 432 } 433 434 static struct symbol *symbols__next(struct symbol *sym) 435 { 436 struct rb_node *n = rb_next(&sym->rb_node); 437 438 if (n) 439 return rb_entry(n, struct symbol, rb_node); 440 441 return NULL; 442 } 443 444 static int symbols__sort_name_cmp(const void *vlhs, const void *vrhs) 445 { 446 const struct symbol *lhs = *((const struct symbol **)vlhs); 447 const struct symbol *rhs = *((const struct symbol **)vrhs); 448 449 return strcmp(lhs->name, rhs->name); 450 } 451 452 static struct symbol **symbols__sort_by_name(struct rb_root_cached *source, size_t *len) 453 { 454 struct rb_node *nd; 455 struct symbol **result; 456 size_t i = 0, size = 0; 457 458 for (nd = rb_first_cached(source); nd; nd = rb_next(nd)) 459 size++; 460 461 result = malloc(sizeof(*result) * size); 462 if (!result) 463 return NULL; 464 465 for (nd = rb_first_cached(source); nd; nd = rb_next(nd)) { 466 struct symbol *pos = rb_entry(nd, struct symbol, rb_node); 467 468 result[i++] = pos; 469 } 470 qsort(result, size, sizeof(*result), symbols__sort_name_cmp); 471 *len = size; 472 return result; 473 } 474 475 int symbol__match_symbol_name(const char *name, const char *str, 476 enum symbol_tag_include includes) 477 { 478 const char *versioning; 479 480 if (includes == SYMBOL_TAG_INCLUDE__DEFAULT_ONLY && 481 (versioning = strstr(name, "@@"))) { 482 int len = strlen(str); 483 484 if (len < versioning - name) 485 len = versioning - name; 486 487 return arch__compare_symbol_names_n(name, str, len); 488 } else 489 return arch__compare_symbol_names(name, str); 490 } 491 492 static struct symbol *symbols__find_by_name(struct symbol *symbols[], 493 size_t symbols_len, 494 const char *name, 495 enum symbol_tag_include includes, 496 size_t *found_idx) 497 { 498 size_t i, lower = 0, upper = symbols_len; 499 struct symbol *s = NULL; 500 501 if (found_idx) 502 *found_idx = SIZE_MAX; 503 504 if (!symbols_len) 505 return NULL; 506 507 while (lower < upper) { 508 int cmp; 509 510 i = (lower + upper) / 2; 511 cmp = symbol__match_symbol_name(symbols[i]->name, name, includes); 512 513 if (cmp > 0) 514 upper = i; 515 else if (cmp < 0) 516 lower = i + 1; 517 else { 518 if (found_idx) 519 *found_idx = i; 520 s = symbols[i]; 521 break; 522 } 523 } 524 if (s && includes != SYMBOL_TAG_INCLUDE__DEFAULT_ONLY) { 525 /* return first symbol that has same name (if any) */ 526 for (; i > 0; i--) { 527 struct symbol *tmp = symbols[i - 1]; 528 529 if (!arch__compare_symbol_names(tmp->name, s->name)) { 530 if (found_idx) 531 *found_idx = i - 1; 532 s = tmp; 533 } else 534 break; 535 } 536 } 537 assert(!found_idx || !s || s == symbols[*found_idx]); 538 return s; 539 } 540 541 void dso__reset_find_symbol_cache(struct dso *dso) 542 { 543 dso__set_last_find_result_addr(dso, 0); 544 dso__set_last_find_result_symbol(dso, NULL); 545 } 546 547 void dso__insert_symbol(struct dso *dso, struct symbol *sym) 548 { 549 __symbols__insert(dso__symbols(dso), sym, dso__kernel(dso)); 550 551 /* update the symbol cache if necessary */ 552 if (dso__last_find_result_addr(dso) >= sym->start && 553 (dso__last_find_result_addr(dso) < sym->end || 554 sym->start == sym->end)) { 555 dso__set_last_find_result_symbol(dso, sym); 556 } 557 } 558 559 void dso__delete_symbol(struct dso *dso, struct symbol *sym) 560 { 561 rb_erase_cached(&sym->rb_node, dso__symbols(dso)); 562 symbol__delete(sym); 563 dso__reset_find_symbol_cache(dso); 564 } 565 566 struct symbol *dso__find_symbol(struct dso *dso, u64 addr) 567 { 568 if (dso__last_find_result_addr(dso) != addr || dso__last_find_result_symbol(dso) == NULL) { 569 dso__set_last_find_result_addr(dso, addr); 570 dso__set_last_find_result_symbol(dso, symbols__find(dso__symbols(dso), addr)); 571 } 572 573 return dso__last_find_result_symbol(dso); 574 } 575 576 struct symbol *dso__find_symbol_nocache(struct dso *dso, u64 addr) 577 { 578 return symbols__find(dso__symbols(dso), addr); 579 } 580 581 struct symbol *dso__first_symbol(struct dso *dso) 582 { 583 return symbols__first(dso__symbols(dso)); 584 } 585 586 struct symbol *dso__last_symbol(struct dso *dso) 587 { 588 return symbols__last(dso__symbols(dso)); 589 } 590 591 struct symbol *dso__next_symbol(struct symbol *sym) 592 { 593 return symbols__next(sym); 594 } 595 596 struct symbol *dso__next_symbol_by_name(struct dso *dso, size_t *idx) 597 { 598 if (*idx + 1 >= dso__symbol_names_len(dso)) 599 return NULL; 600 601 ++*idx; 602 return dso__symbol_names(dso)[*idx]; 603 } 604 605 /* 606 * Returns first symbol that matched with @name. 607 */ 608 struct symbol *dso__find_symbol_by_name(struct dso *dso, const char *name, size_t *idx) 609 { 610 struct symbol *s = symbols__find_by_name(dso__symbol_names(dso), 611 dso__symbol_names_len(dso), 612 name, SYMBOL_TAG_INCLUDE__NONE, idx); 613 if (!s) { 614 s = symbols__find_by_name(dso__symbol_names(dso), dso__symbol_names_len(dso), 615 name, SYMBOL_TAG_INCLUDE__DEFAULT_ONLY, idx); 616 } 617 return s; 618 } 619 620 void dso__sort_by_name(struct dso *dso) 621 { 622 mutex_lock(dso__lock(dso)); 623 if (!dso__sorted_by_name(dso)) { 624 size_t len; 625 626 dso__set_symbol_names(dso, symbols__sort_by_name(dso__symbols(dso), &len)); 627 if (dso__symbol_names(dso)) { 628 dso__set_symbol_names_len(dso, len); 629 dso__set_sorted_by_name(dso); 630 } 631 } 632 mutex_unlock(dso__lock(dso)); 633 } 634 635 /* 636 * While we find nice hex chars, build a long_val. 637 * Return number of chars processed. 638 */ 639 static int hex2u64(const char *ptr, u64 *long_val) 640 { 641 char *p; 642 643 *long_val = strtoull(ptr, &p, 16); 644 645 return p - ptr; 646 } 647 648 649 int modules__parse(const char *filename, void *arg, 650 int (*process_module)(void *arg, const char *name, 651 u64 start, u64 size)) 652 { 653 char *line = NULL; 654 size_t n; 655 FILE *file; 656 int err = 0; 657 658 file = fopen(filename, "r"); 659 if (file == NULL) 660 return -1; 661 662 while (1) { 663 char name[PATH_MAX]; 664 u64 start, size; 665 char *sep, *endptr; 666 ssize_t line_len; 667 668 line_len = getline(&line, &n, file); 669 if (line_len < 0) { 670 if (feof(file)) 671 break; 672 err = -1; 673 goto out; 674 } 675 676 if (!line) { 677 err = -1; 678 goto out; 679 } 680 681 line[--line_len] = '\0'; /* \n */ 682 683 sep = strrchr(line, 'x'); 684 if (sep == NULL) 685 continue; 686 687 hex2u64(sep + 1, &start); 688 689 sep = strchr(line, ' '); 690 if (sep == NULL) 691 continue; 692 693 *sep = '\0'; 694 695 scnprintf(name, sizeof(name), "[%s]", line); 696 697 size = strtoul(sep + 1, &endptr, 0); 698 if (*endptr != ' ' && *endptr != '\t') 699 continue; 700 701 err = process_module(arg, name, start, size); 702 if (err) 703 break; 704 } 705 out: 706 free(line); 707 fclose(file); 708 return err; 709 } 710 711 /* 712 * These are symbols in the kernel image, so make sure that 713 * sym is from a kernel DSO. 714 */ 715 static bool symbol__is_idle(const char *name) 716 { 717 const char * const idle_symbols[] = { 718 "acpi_idle_do_entry", 719 "acpi_processor_ffh_cstate_enter", 720 "arch_cpu_idle", 721 "cpu_idle", 722 "cpu_startup_entry", 723 "idle_cpu", 724 "intel_idle", 725 "intel_idle_ibrs", 726 "default_idle", 727 "native_safe_halt", 728 "enter_idle", 729 "exit_idle", 730 "mwait_idle", 731 "mwait_idle_with_hints", 732 "mwait_idle_with_hints.constprop.0", 733 "poll_idle", 734 "ppc64_runlatch_off", 735 "pseries_dedicated_idle_sleep", 736 "psw_idle", 737 "psw_idle_exit", 738 NULL 739 }; 740 int i; 741 static struct strlist *idle_symbols_list; 742 743 if (idle_symbols_list) 744 return strlist__has_entry(idle_symbols_list, name); 745 746 idle_symbols_list = strlist__new(NULL, NULL); 747 748 for (i = 0; idle_symbols[i]; i++) 749 strlist__add(idle_symbols_list, idle_symbols[i]); 750 751 return strlist__has_entry(idle_symbols_list, name); 752 } 753 754 static int map__process_kallsym_symbol(void *arg, const char *name, 755 char type, u64 start) 756 { 757 struct symbol *sym; 758 struct dso *dso = arg; 759 struct rb_root_cached *root = dso__symbols(dso); 760 761 if (!symbol_type__filter(type)) 762 return 0; 763 764 /* Ignore local symbols for ARM modules */ 765 if (name[0] == '$') 766 return 0; 767 768 /* 769 * module symbols are not sorted so we add all 770 * symbols, setting length to 0, and rely on 771 * symbols__fixup_end() to fix it up. 772 */ 773 sym = symbol__new(start, 0, kallsyms2elf_binding(type), kallsyms2elf_type(type), name); 774 if (sym == NULL) 775 return -ENOMEM; 776 /* 777 * We will pass the symbols to the filter later, in 778 * map__split_kallsyms, when we have split the maps per module 779 */ 780 __symbols__insert(root, sym, !strchr(name, '[')); 781 782 return 0; 783 } 784 785 /* 786 * Loads the function entries in /proc/kallsyms into kernel_map->dso, 787 * so that we can in the next step set the symbol ->end address and then 788 * call kernel_maps__split_kallsyms. 789 */ 790 static int dso__load_all_kallsyms(struct dso *dso, const char *filename) 791 { 792 return kallsyms__parse(filename, dso, map__process_kallsym_symbol); 793 } 794 795 static int maps__split_kallsyms_for_kcore(struct maps *kmaps, struct dso *dso) 796 { 797 struct symbol *pos; 798 int count = 0; 799 struct rb_root_cached *root = dso__symbols(dso); 800 struct rb_root_cached old_root = *root; 801 struct rb_node *next = rb_first_cached(root); 802 803 if (!kmaps) 804 return -1; 805 806 *root = RB_ROOT_CACHED; 807 808 while (next) { 809 struct map *curr_map; 810 struct dso *curr_map_dso; 811 char *module; 812 813 pos = rb_entry(next, struct symbol, rb_node); 814 next = rb_next(&pos->rb_node); 815 816 rb_erase_cached(&pos->rb_node, &old_root); 817 RB_CLEAR_NODE(&pos->rb_node); 818 module = strchr(pos->name, '\t'); 819 if (module) 820 *module = '\0'; 821 822 curr_map = maps__find(kmaps, pos->start); 823 824 if (!curr_map) { 825 symbol__delete(pos); 826 continue; 827 } 828 curr_map_dso = map__dso(curr_map); 829 pos->start -= map__start(curr_map) - map__pgoff(curr_map); 830 if (pos->end > map__end(curr_map)) 831 pos->end = map__end(curr_map); 832 if (pos->end) 833 pos->end -= map__start(curr_map) - map__pgoff(curr_map); 834 symbols__insert(dso__symbols(curr_map_dso), pos); 835 ++count; 836 map__put(curr_map); 837 } 838 839 /* Symbols have been adjusted */ 840 dso__set_adjust_symbols(dso, true); 841 842 return count; 843 } 844 845 /* 846 * Split the symbols into maps, making sure there are no overlaps, i.e. the 847 * kernel range is broken in several maps, named [kernel].N, as we don't have 848 * the original ELF section names vmlinux have. 849 */ 850 static int maps__split_kallsyms(struct maps *kmaps, struct dso *dso, u64 delta, 851 struct map *initial_map) 852 { 853 struct machine *machine; 854 struct map *curr_map = map__get(initial_map); 855 struct symbol *pos; 856 int count = 0, moved = 0; 857 struct rb_root_cached *root = dso__symbols(dso); 858 struct rb_node *next = rb_first_cached(root); 859 int kernel_range = 0; 860 bool x86_64; 861 862 if (!kmaps) 863 return -1; 864 865 machine = maps__machine(kmaps); 866 867 x86_64 = machine__is(machine, "x86_64"); 868 869 while (next) { 870 char *module; 871 872 pos = rb_entry(next, struct symbol, rb_node); 873 next = rb_next(&pos->rb_node); 874 875 module = strchr(pos->name, '\t'); 876 if (module) { 877 struct dso *curr_map_dso; 878 879 if (!symbol_conf.use_modules) 880 goto discard_symbol; 881 882 *module++ = '\0'; 883 curr_map_dso = map__dso(curr_map); 884 if (strcmp(dso__short_name(curr_map_dso), module)) { 885 if (!RC_CHK_EQUAL(curr_map, initial_map) && 886 dso__kernel(dso) == DSO_SPACE__KERNEL_GUEST && 887 machine__is_default_guest(machine)) { 888 /* 889 * We assume all symbols of a module are 890 * continuous in * kallsyms, so curr_map 891 * points to a module and all its 892 * symbols are in its kmap. Mark it as 893 * loaded. 894 */ 895 dso__set_loaded(curr_map_dso); 896 } 897 898 map__zput(curr_map); 899 curr_map = maps__find_by_name(kmaps, module); 900 if (curr_map == NULL) { 901 pr_debug("%s/proc/{kallsyms,modules} " 902 "inconsistency while looking " 903 "for \"%s\" module!\n", 904 machine->root_dir, module); 905 curr_map = map__get(initial_map); 906 goto discard_symbol; 907 } 908 curr_map_dso = map__dso(curr_map); 909 if (dso__loaded(curr_map_dso) && 910 !machine__is_default_guest(machine)) 911 goto discard_symbol; 912 } 913 /* 914 * So that we look just like we get from .ko files, 915 * i.e. not prelinked, relative to initial_map->start. 916 */ 917 pos->start = map__map_ip(curr_map, pos->start); 918 pos->end = map__map_ip(curr_map, pos->end); 919 } else if (x86_64 && is_entry_trampoline(pos->name)) { 920 /* 921 * These symbols are not needed anymore since the 922 * trampoline maps refer to the text section and it's 923 * symbols instead. Avoid having to deal with 924 * relocations, and the assumption that the first symbol 925 * is the start of kernel text, by simply removing the 926 * symbols at this point. 927 */ 928 goto discard_symbol; 929 } else if (!RC_CHK_EQUAL(curr_map, initial_map)) { 930 char dso_name[PATH_MAX]; 931 struct dso *ndso; 932 933 if (delta) { 934 /* Kernel was relocated at boot time */ 935 pos->start -= delta; 936 pos->end -= delta; 937 } 938 939 if (count == 0) { 940 map__zput(curr_map); 941 curr_map = map__get(initial_map); 942 goto add_symbol; 943 } 944 945 if (dso__kernel(dso) == DSO_SPACE__KERNEL_GUEST) 946 snprintf(dso_name, sizeof(dso_name), 947 "[guest.kernel].%d", 948 kernel_range++); 949 else 950 snprintf(dso_name, sizeof(dso_name), 951 "[kernel].%d", 952 kernel_range++); 953 954 ndso = dso__new(dso_name); 955 map__zput(curr_map); 956 if (ndso == NULL) 957 return -1; 958 959 dso__set_kernel(ndso, dso__kernel(dso)); 960 961 curr_map = map__new2(pos->start, ndso); 962 if (curr_map == NULL) { 963 dso__put(ndso); 964 return -1; 965 } 966 967 map__set_mapping_type(curr_map, MAPPING_TYPE__IDENTITY); 968 if (maps__insert(kmaps, curr_map)) { 969 map__zput(curr_map); 970 dso__put(ndso); 971 return -1; 972 } 973 ++kernel_range; 974 } else if (delta) { 975 /* Kernel was relocated at boot time */ 976 pos->start -= delta; 977 pos->end -= delta; 978 } 979 add_symbol: 980 if (!RC_CHK_EQUAL(curr_map, initial_map)) { 981 struct dso *curr_map_dso = map__dso(curr_map); 982 983 rb_erase_cached(&pos->rb_node, root); 984 symbols__insert(dso__symbols(curr_map_dso), pos); 985 ++moved; 986 } else 987 ++count; 988 989 continue; 990 discard_symbol: 991 rb_erase_cached(&pos->rb_node, root); 992 symbol__delete(pos); 993 } 994 995 if (!RC_CHK_EQUAL(curr_map, initial_map) && 996 dso__kernel(dso) == DSO_SPACE__KERNEL_GUEST && 997 machine__is_default_guest(maps__machine(kmaps))) { 998 dso__set_loaded(map__dso(curr_map)); 999 } 1000 map__put(curr_map); 1001 return count + moved; 1002 } 1003 1004 bool symbol__restricted_filename(const char *filename, 1005 const char *restricted_filename) 1006 { 1007 bool restricted = false; 1008 1009 if (symbol_conf.kptr_restrict) { 1010 char *r = realpath(filename, NULL); 1011 1012 if (r != NULL) { 1013 restricted = strcmp(r, restricted_filename) == 0; 1014 free(r); 1015 return restricted; 1016 } 1017 } 1018 1019 return restricted; 1020 } 1021 1022 struct module_info { 1023 struct rb_node rb_node; 1024 char *name; 1025 u64 start; 1026 }; 1027 1028 static void add_module(struct module_info *mi, struct rb_root *modules) 1029 { 1030 struct rb_node **p = &modules->rb_node; 1031 struct rb_node *parent = NULL; 1032 struct module_info *m; 1033 1034 while (*p != NULL) { 1035 parent = *p; 1036 m = rb_entry(parent, struct module_info, rb_node); 1037 if (strcmp(mi->name, m->name) < 0) 1038 p = &(*p)->rb_left; 1039 else 1040 p = &(*p)->rb_right; 1041 } 1042 rb_link_node(&mi->rb_node, parent, p); 1043 rb_insert_color(&mi->rb_node, modules); 1044 } 1045 1046 static void delete_modules(struct rb_root *modules) 1047 { 1048 struct module_info *mi; 1049 struct rb_node *next = rb_first(modules); 1050 1051 while (next) { 1052 mi = rb_entry(next, struct module_info, rb_node); 1053 next = rb_next(&mi->rb_node); 1054 rb_erase(&mi->rb_node, modules); 1055 zfree(&mi->name); 1056 free(mi); 1057 } 1058 } 1059 1060 static struct module_info *find_module(const char *name, 1061 struct rb_root *modules) 1062 { 1063 struct rb_node *n = modules->rb_node; 1064 1065 while (n) { 1066 struct module_info *m; 1067 int cmp; 1068 1069 m = rb_entry(n, struct module_info, rb_node); 1070 cmp = strcmp(name, m->name); 1071 if (cmp < 0) 1072 n = n->rb_left; 1073 else if (cmp > 0) 1074 n = n->rb_right; 1075 else 1076 return m; 1077 } 1078 1079 return NULL; 1080 } 1081 1082 static int __read_proc_modules(void *arg, const char *name, u64 start, 1083 u64 size __maybe_unused) 1084 { 1085 struct rb_root *modules = arg; 1086 struct module_info *mi; 1087 1088 mi = zalloc(sizeof(struct module_info)); 1089 if (!mi) 1090 return -ENOMEM; 1091 1092 mi->name = strdup(name); 1093 mi->start = start; 1094 1095 if (!mi->name) { 1096 free(mi); 1097 return -ENOMEM; 1098 } 1099 1100 add_module(mi, modules); 1101 1102 return 0; 1103 } 1104 1105 static int read_proc_modules(const char *filename, struct rb_root *modules) 1106 { 1107 if (symbol__restricted_filename(filename, "/proc/modules")) 1108 return -1; 1109 1110 if (modules__parse(filename, modules, __read_proc_modules)) { 1111 delete_modules(modules); 1112 return -1; 1113 } 1114 1115 return 0; 1116 } 1117 1118 int compare_proc_modules(const char *from, const char *to) 1119 { 1120 struct rb_root from_modules = RB_ROOT; 1121 struct rb_root to_modules = RB_ROOT; 1122 struct rb_node *from_node, *to_node; 1123 struct module_info *from_m, *to_m; 1124 int ret = -1; 1125 1126 if (read_proc_modules(from, &from_modules)) 1127 return -1; 1128 1129 if (read_proc_modules(to, &to_modules)) 1130 goto out_delete_from; 1131 1132 from_node = rb_first(&from_modules); 1133 to_node = rb_first(&to_modules); 1134 while (from_node) { 1135 if (!to_node) 1136 break; 1137 1138 from_m = rb_entry(from_node, struct module_info, rb_node); 1139 to_m = rb_entry(to_node, struct module_info, rb_node); 1140 1141 if (from_m->start != to_m->start || 1142 strcmp(from_m->name, to_m->name)) 1143 break; 1144 1145 from_node = rb_next(from_node); 1146 to_node = rb_next(to_node); 1147 } 1148 1149 if (!from_node && !to_node) 1150 ret = 0; 1151 1152 delete_modules(&to_modules); 1153 out_delete_from: 1154 delete_modules(&from_modules); 1155 1156 return ret; 1157 } 1158 1159 static int do_validate_kcore_modules_cb(struct map *old_map, void *data) 1160 { 1161 struct rb_root *modules = data; 1162 struct module_info *mi; 1163 struct dso *dso; 1164 1165 if (!__map__is_kmodule(old_map)) 1166 return 0; 1167 1168 dso = map__dso(old_map); 1169 /* Module must be in memory at the same address */ 1170 mi = find_module(dso__short_name(dso), modules); 1171 if (!mi || mi->start != map__start(old_map)) 1172 return -EINVAL; 1173 1174 return 0; 1175 } 1176 1177 static int do_validate_kcore_modules(const char *filename, struct maps *kmaps) 1178 { 1179 struct rb_root modules = RB_ROOT; 1180 int err; 1181 1182 err = read_proc_modules(filename, &modules); 1183 if (err) 1184 return err; 1185 1186 err = maps__for_each_map(kmaps, do_validate_kcore_modules_cb, &modules); 1187 1188 delete_modules(&modules); 1189 return err; 1190 } 1191 1192 /* 1193 * If kallsyms is referenced by name then we look for filename in the same 1194 * directory. 1195 */ 1196 static bool filename_from_kallsyms_filename(char *filename, 1197 const char *base_name, 1198 const char *kallsyms_filename) 1199 { 1200 char *name; 1201 1202 strcpy(filename, kallsyms_filename); 1203 name = strrchr(filename, '/'); 1204 if (!name) 1205 return false; 1206 1207 name += 1; 1208 1209 if (!strcmp(name, "kallsyms")) { 1210 strcpy(name, base_name); 1211 return true; 1212 } 1213 1214 return false; 1215 } 1216 1217 static int validate_kcore_modules(const char *kallsyms_filename, 1218 struct map *map) 1219 { 1220 struct maps *kmaps = map__kmaps(map); 1221 char modules_filename[PATH_MAX]; 1222 1223 if (!kmaps) 1224 return -EINVAL; 1225 1226 if (!filename_from_kallsyms_filename(modules_filename, "modules", 1227 kallsyms_filename)) 1228 return -EINVAL; 1229 1230 if (do_validate_kcore_modules(modules_filename, kmaps)) 1231 return -EINVAL; 1232 1233 return 0; 1234 } 1235 1236 static int validate_kcore_addresses(const char *kallsyms_filename, 1237 struct map *map) 1238 { 1239 struct kmap *kmap = map__kmap(map); 1240 1241 if (!kmap) 1242 return -EINVAL; 1243 1244 if (kmap->ref_reloc_sym && kmap->ref_reloc_sym->name) { 1245 u64 start; 1246 1247 if (kallsyms__get_function_start(kallsyms_filename, 1248 kmap->ref_reloc_sym->name, &start)) 1249 return -ENOENT; 1250 if (start != kmap->ref_reloc_sym->addr) 1251 return -EINVAL; 1252 } 1253 1254 return validate_kcore_modules(kallsyms_filename, map); 1255 } 1256 1257 struct kcore_mapfn_data { 1258 struct dso *dso; 1259 struct list_head maps; 1260 }; 1261 1262 static int kcore_mapfn(u64 start, u64 len, u64 pgoff, void *data) 1263 { 1264 struct kcore_mapfn_data *md = data; 1265 struct map_list_node *list_node = map_list_node__new(); 1266 1267 if (!list_node) 1268 return -ENOMEM; 1269 1270 list_node->map = map__new2(start, md->dso); 1271 if (!list_node->map) { 1272 free(list_node); 1273 return -ENOMEM; 1274 } 1275 1276 map__set_end(list_node->map, map__start(list_node->map) + len); 1277 map__set_pgoff(list_node->map, pgoff); 1278 1279 list_add(&list_node->node, &md->maps); 1280 1281 return 0; 1282 } 1283 1284 static bool remove_old_maps(struct map *map, void *data) 1285 { 1286 const struct map *map_to_save = data; 1287 1288 /* 1289 * We need to preserve eBPF maps even if they are covered by kcore, 1290 * because we need to access eBPF dso for source data. 1291 */ 1292 return !RC_CHK_EQUAL(map, map_to_save) && !__map__is_bpf_prog(map); 1293 } 1294 1295 static int dso__load_kcore(struct dso *dso, struct map *map, 1296 const char *kallsyms_filename) 1297 { 1298 struct maps *kmaps = map__kmaps(map); 1299 struct kcore_mapfn_data md; 1300 struct map *map_ref, *replacement_map = NULL; 1301 struct machine *machine; 1302 bool is_64_bit; 1303 int err, fd; 1304 char kcore_filename[PATH_MAX]; 1305 u64 stext; 1306 1307 if (!kmaps) 1308 return -EINVAL; 1309 1310 machine = maps__machine(kmaps); 1311 1312 /* This function requires that the map is the kernel map */ 1313 if (!__map__is_kernel(map)) 1314 return -EINVAL; 1315 1316 if (!filename_from_kallsyms_filename(kcore_filename, "kcore", 1317 kallsyms_filename)) 1318 return -EINVAL; 1319 1320 /* Modules and kernel must be present at their original addresses */ 1321 if (validate_kcore_addresses(kallsyms_filename, map)) 1322 return -EINVAL; 1323 1324 md.dso = dso; 1325 INIT_LIST_HEAD(&md.maps); 1326 1327 fd = open(kcore_filename, O_RDONLY); 1328 if (fd < 0) { 1329 pr_debug("Failed to open %s. Note /proc/kcore requires CAP_SYS_RAWIO capability to access.\n", 1330 kcore_filename); 1331 return -EINVAL; 1332 } 1333 1334 /* Read new maps into temporary lists */ 1335 err = file__read_maps(fd, map__prot(map) & PROT_EXEC, kcore_mapfn, &md, 1336 &is_64_bit); 1337 if (err) 1338 goto out_err; 1339 dso__set_is_64_bit(dso, is_64_bit); 1340 1341 if (list_empty(&md.maps)) { 1342 err = -EINVAL; 1343 goto out_err; 1344 } 1345 1346 /* Remove old maps */ 1347 maps__remove_maps(kmaps, remove_old_maps, map); 1348 machine->trampolines_mapped = false; 1349 1350 /* Find the kernel map using the '_stext' symbol */ 1351 if (!kallsyms__get_function_start(kallsyms_filename, "_stext", &stext)) { 1352 u64 replacement_size = 0; 1353 struct map_list_node *new_node; 1354 1355 list_for_each_entry(new_node, &md.maps, node) { 1356 struct map *new_map = new_node->map; 1357 u64 new_size = map__size(new_map); 1358 1359 if (!(stext >= map__start(new_map) && stext < map__end(new_map))) 1360 continue; 1361 1362 /* 1363 * On some architectures, ARM64 for example, the kernel 1364 * text can get allocated inside of the vmalloc segment. 1365 * Select the smallest matching segment, in case stext 1366 * falls within more than one in the list. 1367 */ 1368 if (!replacement_map || new_size < replacement_size) { 1369 replacement_map = new_map; 1370 replacement_size = new_size; 1371 } 1372 } 1373 } 1374 1375 if (!replacement_map) 1376 replacement_map = list_entry(md.maps.next, struct map_list_node, node)->map; 1377 1378 /* 1379 * Update addresses of vmlinux map. Re-insert it to ensure maps are 1380 * correctly ordered. Do this before using maps__merge_in() for the 1381 * remaining maps so vmlinux gets split if necessary. 1382 */ 1383 map_ref = map__get(map); 1384 maps__remove(kmaps, map_ref); 1385 1386 map__set_start(map_ref, map__start(replacement_map)); 1387 map__set_end(map_ref, map__end(replacement_map)); 1388 map__set_pgoff(map_ref, map__pgoff(replacement_map)); 1389 map__set_mapping_type(map_ref, map__mapping_type(replacement_map)); 1390 1391 err = maps__insert(kmaps, map_ref); 1392 map__put(map_ref); 1393 if (err) 1394 goto out_err; 1395 1396 /* Add new maps */ 1397 while (!list_empty(&md.maps)) { 1398 struct map_list_node *new_node = list_entry(md.maps.next, struct map_list_node, node); 1399 struct map *new_map = new_node->map; 1400 1401 list_del_init(&new_node->node); 1402 1403 /* skip if replacement_map, already inserted above */ 1404 if (!RC_CHK_EQUAL(new_map, replacement_map)) { 1405 /* 1406 * Merge kcore map into existing maps, 1407 * and ensure that current maps (eBPF) 1408 * stay intact. 1409 */ 1410 if (maps__merge_in(kmaps, new_map)) { 1411 err = -EINVAL; 1412 goto out_err; 1413 } 1414 } 1415 free(new_node); 1416 } 1417 1418 if (machine__is(machine, "x86_64")) { 1419 u64 addr; 1420 1421 /* 1422 * If one of the corresponding symbols is there, assume the 1423 * entry trampoline maps are too. 1424 */ 1425 if (!kallsyms__get_function_start(kallsyms_filename, 1426 ENTRY_TRAMPOLINE_NAME, 1427 &addr)) 1428 machine->trampolines_mapped = true; 1429 } 1430 1431 /* 1432 * Set the data type and long name so that kcore can be read via 1433 * dso__data_read_addr(). 1434 */ 1435 if (dso__kernel(dso) == DSO_SPACE__KERNEL_GUEST) 1436 dso__set_binary_type(dso, DSO_BINARY_TYPE__GUEST_KCORE); 1437 else 1438 dso__set_binary_type(dso, DSO_BINARY_TYPE__KCORE); 1439 dso__set_long_name(dso, strdup(kcore_filename), true); 1440 1441 close(fd); 1442 1443 if (map__prot(map) & PROT_EXEC) 1444 pr_debug("Using %s for kernel object code\n", kcore_filename); 1445 else 1446 pr_debug("Using %s for kernel data\n", kcore_filename); 1447 1448 return 0; 1449 1450 out_err: 1451 while (!list_empty(&md.maps)) { 1452 struct map_list_node *list_node; 1453 1454 list_node = list_entry(md.maps.next, struct map_list_node, node); 1455 list_del_init(&list_node->node); 1456 map__zput(list_node->map); 1457 free(list_node); 1458 } 1459 close(fd); 1460 return err; 1461 } 1462 1463 /* 1464 * If the kernel is relocated at boot time, kallsyms won't match. Compute the 1465 * delta based on the relocation reference symbol. 1466 */ 1467 static int kallsyms__delta(struct kmap *kmap, const char *filename, u64 *delta) 1468 { 1469 u64 addr; 1470 1471 if (!kmap->ref_reloc_sym || !kmap->ref_reloc_sym->name) 1472 return 0; 1473 1474 if (kallsyms__get_function_start(filename, kmap->ref_reloc_sym->name, &addr)) 1475 return -1; 1476 1477 *delta = addr - kmap->ref_reloc_sym->addr; 1478 return 0; 1479 } 1480 1481 int __dso__load_kallsyms(struct dso *dso, const char *filename, 1482 struct map *map, bool no_kcore) 1483 { 1484 struct kmap *kmap = map__kmap(map); 1485 u64 delta = 0; 1486 1487 if (symbol__restricted_filename(filename, "/proc/kallsyms")) 1488 return -1; 1489 1490 if (!kmap || !kmap->kmaps) 1491 return -1; 1492 1493 if (dso__load_all_kallsyms(dso, filename) < 0) 1494 return -1; 1495 1496 if (kallsyms__delta(kmap, filename, &delta)) 1497 return -1; 1498 1499 symbols__fixup_end(dso__symbols(dso), true); 1500 symbols__fixup_duplicate(dso__symbols(dso)); 1501 1502 if (dso__kernel(dso) == DSO_SPACE__KERNEL_GUEST) 1503 dso__set_symtab_type(dso, DSO_BINARY_TYPE__GUEST_KALLSYMS); 1504 else 1505 dso__set_symtab_type(dso, DSO_BINARY_TYPE__KALLSYMS); 1506 1507 if (!no_kcore && !dso__load_kcore(dso, map, filename)) 1508 return maps__split_kallsyms_for_kcore(kmap->kmaps, dso); 1509 else 1510 return maps__split_kallsyms(kmap->kmaps, dso, delta, map); 1511 } 1512 1513 int dso__load_kallsyms(struct dso *dso, const char *filename, 1514 struct map *map) 1515 { 1516 return __dso__load_kallsyms(dso, filename, map, false); 1517 } 1518 1519 static int dso__load_perf_map(const char *map_path, struct dso *dso) 1520 { 1521 char *line = NULL; 1522 size_t n; 1523 FILE *file; 1524 int nr_syms = 0; 1525 1526 file = fopen(map_path, "r"); 1527 if (file == NULL) 1528 goto out_failure; 1529 1530 while (!feof(file)) { 1531 u64 start, size; 1532 struct symbol *sym; 1533 int line_len, len; 1534 1535 line_len = getline(&line, &n, file); 1536 if (line_len < 0) 1537 break; 1538 1539 if (!line) 1540 goto out_failure; 1541 1542 line[--line_len] = '\0'; /* \n */ 1543 1544 len = hex2u64(line, &start); 1545 1546 len++; 1547 if (len + 2 >= line_len) 1548 continue; 1549 1550 len += hex2u64(line + len, &size); 1551 1552 len++; 1553 if (len + 2 >= line_len) 1554 continue; 1555 1556 sym = symbol__new(start, size, STB_GLOBAL, STT_FUNC, line + len); 1557 1558 if (sym == NULL) 1559 goto out_delete_line; 1560 1561 symbols__insert(dso__symbols(dso), sym); 1562 nr_syms++; 1563 } 1564 1565 free(line); 1566 fclose(file); 1567 1568 return nr_syms; 1569 1570 out_delete_line: 1571 free(line); 1572 out_failure: 1573 return -1; 1574 } 1575 1576 #ifdef HAVE_LIBBFD_SUPPORT 1577 #define PACKAGE 'perf' 1578 #include <bfd.h> 1579 1580 static int bfd_symbols__cmpvalue(const void *a, const void *b) 1581 { 1582 const asymbol *as = *(const asymbol **)a, *bs = *(const asymbol **)b; 1583 1584 if (bfd_asymbol_value(as) != bfd_asymbol_value(bs)) 1585 return bfd_asymbol_value(as) - bfd_asymbol_value(bs); 1586 1587 return bfd_asymbol_name(as)[0] - bfd_asymbol_name(bs)[0]; 1588 } 1589 1590 static int bfd2elf_binding(asymbol *symbol) 1591 { 1592 if (symbol->flags & BSF_WEAK) 1593 return STB_WEAK; 1594 if (symbol->flags & BSF_GLOBAL) 1595 return STB_GLOBAL; 1596 if (symbol->flags & BSF_LOCAL) 1597 return STB_LOCAL; 1598 return -1; 1599 } 1600 1601 int dso__load_bfd_symbols(struct dso *dso, const char *debugfile) 1602 { 1603 int err = -1; 1604 long symbols_size, symbols_count, i; 1605 asection *section; 1606 asymbol **symbols, *sym; 1607 struct symbol *symbol; 1608 bfd *abfd; 1609 u64 start, len; 1610 1611 abfd = bfd_openr(debugfile, NULL); 1612 if (!abfd) 1613 return -1; 1614 1615 if (!bfd_check_format(abfd, bfd_object)) { 1616 pr_debug2("%s: cannot read %s bfd file.\n", __func__, 1617 dso__long_name(dso)); 1618 goto out_close; 1619 } 1620 1621 if (bfd_get_flavour(abfd) == bfd_target_elf_flavour) 1622 goto out_close; 1623 1624 symbols_size = bfd_get_symtab_upper_bound(abfd); 1625 if (symbols_size == 0) { 1626 bfd_close(abfd); 1627 return 0; 1628 } 1629 1630 if (symbols_size < 0) 1631 goto out_close; 1632 1633 symbols = malloc(symbols_size); 1634 if (!symbols) 1635 goto out_close; 1636 1637 symbols_count = bfd_canonicalize_symtab(abfd, symbols); 1638 if (symbols_count < 0) 1639 goto out_free; 1640 1641 section = bfd_get_section_by_name(abfd, ".text"); 1642 if (section) { 1643 for (i = 0; i < symbols_count; ++i) { 1644 if (!strcmp(bfd_asymbol_name(symbols[i]), "__ImageBase") || 1645 !strcmp(bfd_asymbol_name(symbols[i]), "__image_base__")) 1646 break; 1647 } 1648 if (i < symbols_count) { 1649 /* PE symbols can only have 4 bytes, so use .text high bits */ 1650 u64 text_offset = (section->vma - (u32)section->vma) 1651 + (u32)bfd_asymbol_value(symbols[i]); 1652 dso__set_text_offset(dso, text_offset); 1653 dso__set_text_end(dso, (section->vma - text_offset) + section->size); 1654 } else { 1655 dso__set_text_offset(dso, section->vma - section->filepos); 1656 dso__set_text_end(dso, section->filepos + section->size); 1657 } 1658 } 1659 1660 qsort(symbols, symbols_count, sizeof(asymbol *), bfd_symbols__cmpvalue); 1661 1662 #ifdef bfd_get_section 1663 #define bfd_asymbol_section bfd_get_section 1664 #endif 1665 for (i = 0; i < symbols_count; ++i) { 1666 sym = symbols[i]; 1667 section = bfd_asymbol_section(sym); 1668 if (bfd2elf_binding(sym) < 0) 1669 continue; 1670 1671 while (i + 1 < symbols_count && 1672 bfd_asymbol_section(symbols[i + 1]) == section && 1673 bfd2elf_binding(symbols[i + 1]) < 0) 1674 i++; 1675 1676 if (i + 1 < symbols_count && 1677 bfd_asymbol_section(symbols[i + 1]) == section) 1678 len = symbols[i + 1]->value - sym->value; 1679 else 1680 len = section->size - sym->value; 1681 1682 start = bfd_asymbol_value(sym) - dso__text_offset(dso); 1683 symbol = symbol__new(start, len, bfd2elf_binding(sym), STT_FUNC, 1684 bfd_asymbol_name(sym)); 1685 if (!symbol) 1686 goto out_free; 1687 1688 symbols__insert(dso__symbols(dso), symbol); 1689 } 1690 #ifdef bfd_get_section 1691 #undef bfd_asymbol_section 1692 #endif 1693 1694 symbols__fixup_end(dso__symbols(dso), false); 1695 symbols__fixup_duplicate(dso__symbols(dso)); 1696 dso__set_adjust_symbols(dso, true); 1697 1698 err = 0; 1699 out_free: 1700 free(symbols); 1701 out_close: 1702 bfd_close(abfd); 1703 return err; 1704 } 1705 #endif 1706 1707 static bool dso__is_compatible_symtab_type(struct dso *dso, bool kmod, 1708 enum dso_binary_type type) 1709 { 1710 switch (type) { 1711 case DSO_BINARY_TYPE__JAVA_JIT: 1712 case DSO_BINARY_TYPE__DEBUGLINK: 1713 case DSO_BINARY_TYPE__SYSTEM_PATH_DSO: 1714 case DSO_BINARY_TYPE__FEDORA_DEBUGINFO: 1715 case DSO_BINARY_TYPE__UBUNTU_DEBUGINFO: 1716 case DSO_BINARY_TYPE__MIXEDUP_UBUNTU_DEBUGINFO: 1717 case DSO_BINARY_TYPE__BUILDID_DEBUGINFO: 1718 case DSO_BINARY_TYPE__OPENEMBEDDED_DEBUGINFO: 1719 return !kmod && dso__kernel(dso) == DSO_SPACE__USER; 1720 1721 case DSO_BINARY_TYPE__KALLSYMS: 1722 case DSO_BINARY_TYPE__VMLINUX: 1723 case DSO_BINARY_TYPE__KCORE: 1724 return dso__kernel(dso) == DSO_SPACE__KERNEL; 1725 1726 case DSO_BINARY_TYPE__GUEST_KALLSYMS: 1727 case DSO_BINARY_TYPE__GUEST_VMLINUX: 1728 case DSO_BINARY_TYPE__GUEST_KCORE: 1729 return dso__kernel(dso) == DSO_SPACE__KERNEL_GUEST; 1730 1731 case DSO_BINARY_TYPE__GUEST_KMODULE: 1732 case DSO_BINARY_TYPE__GUEST_KMODULE_COMP: 1733 case DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE: 1734 case DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP: 1735 /* 1736 * kernel modules know their symtab type - it's set when 1737 * creating a module dso in machine__addnew_module_map(). 1738 */ 1739 return kmod && dso__symtab_type(dso) == type; 1740 1741 case DSO_BINARY_TYPE__BUILD_ID_CACHE: 1742 case DSO_BINARY_TYPE__BUILD_ID_CACHE_DEBUGINFO: 1743 return true; 1744 1745 case DSO_BINARY_TYPE__BPF_PROG_INFO: 1746 case DSO_BINARY_TYPE__BPF_IMAGE: 1747 case DSO_BINARY_TYPE__OOL: 1748 case DSO_BINARY_TYPE__NOT_FOUND: 1749 default: 1750 return false; 1751 } 1752 } 1753 1754 /* Checks for the existence of the perf-<pid>.map file in two different 1755 * locations. First, if the process is a separate mount namespace, check in 1756 * that namespace using the pid of the innermost pid namespace. If's not in a 1757 * namespace, or the file can't be found there, try in the mount namespace of 1758 * the tracing process using our view of its pid. 1759 */ 1760 static int dso__find_perf_map(char *filebuf, size_t bufsz, 1761 struct nsinfo **nsip) 1762 { 1763 struct nscookie nsc; 1764 struct nsinfo *nsi; 1765 struct nsinfo *nnsi; 1766 int rc = -1; 1767 1768 nsi = *nsip; 1769 1770 if (nsinfo__need_setns(nsi)) { 1771 snprintf(filebuf, bufsz, "/tmp/perf-%d.map", nsinfo__nstgid(nsi)); 1772 nsinfo__mountns_enter(nsi, &nsc); 1773 rc = access(filebuf, R_OK); 1774 nsinfo__mountns_exit(&nsc); 1775 if (rc == 0) 1776 return rc; 1777 } 1778 1779 nnsi = nsinfo__copy(nsi); 1780 if (nnsi) { 1781 nsinfo__put(nsi); 1782 1783 nsinfo__clear_need_setns(nnsi); 1784 snprintf(filebuf, bufsz, "/tmp/perf-%d.map", nsinfo__tgid(nnsi)); 1785 *nsip = nnsi; 1786 rc = 0; 1787 } 1788 1789 return rc; 1790 } 1791 1792 int dso__load(struct dso *dso, struct map *map) 1793 { 1794 char *name; 1795 int ret = -1; 1796 u_int i; 1797 struct machine *machine = NULL; 1798 char *root_dir = (char *) ""; 1799 int ss_pos = 0; 1800 struct symsrc ss_[2]; 1801 struct symsrc *syms_ss = NULL, *runtime_ss = NULL; 1802 bool kmod; 1803 bool perfmap; 1804 struct build_id bid; 1805 struct nscookie nsc; 1806 char newmapname[PATH_MAX]; 1807 const char *map_path = dso__long_name(dso); 1808 1809 mutex_lock(dso__lock(dso)); 1810 perfmap = is_perf_pid_map_name(map_path); 1811 1812 if (perfmap) { 1813 if (dso__nsinfo(dso) && 1814 (dso__find_perf_map(newmapname, sizeof(newmapname), 1815 dso__nsinfo_ptr(dso)) == 0)) { 1816 map_path = newmapname; 1817 } 1818 } 1819 1820 nsinfo__mountns_enter(dso__nsinfo(dso), &nsc); 1821 1822 /* check again under the dso->lock */ 1823 if (dso__loaded(dso)) { 1824 ret = 1; 1825 goto out; 1826 } 1827 1828 kmod = dso__is_kmod(dso); 1829 1830 if (dso__kernel(dso) && !kmod) { 1831 if (dso__kernel(dso) == DSO_SPACE__KERNEL) 1832 ret = dso__load_kernel_sym(dso, map); 1833 else if (dso__kernel(dso) == DSO_SPACE__KERNEL_GUEST) 1834 ret = dso__load_guest_kernel_sym(dso, map); 1835 1836 machine = maps__machine(map__kmaps(map)); 1837 if (machine__is(machine, "x86_64")) 1838 machine__map_x86_64_entry_trampolines(machine, dso); 1839 goto out; 1840 } 1841 1842 dso__set_adjust_symbols(dso, false); 1843 1844 if (perfmap) { 1845 ret = dso__load_perf_map(map_path, dso); 1846 dso__set_symtab_type(dso, ret > 0 1847 ? DSO_BINARY_TYPE__JAVA_JIT 1848 : DSO_BINARY_TYPE__NOT_FOUND); 1849 goto out; 1850 } 1851 1852 if (machine) 1853 root_dir = machine->root_dir; 1854 1855 name = malloc(PATH_MAX); 1856 if (!name) 1857 goto out; 1858 1859 /* 1860 * Read the build id if possible. This is required for 1861 * DSO_BINARY_TYPE__BUILDID_DEBUGINFO to work 1862 */ 1863 if (!dso__has_build_id(dso) && 1864 is_regular_file(dso__long_name(dso))) { 1865 __symbol__join_symfs(name, PATH_MAX, dso__long_name(dso)); 1866 if (filename__read_build_id(name, &bid) > 0) 1867 dso__set_build_id(dso, &bid); 1868 } 1869 1870 /* 1871 * Iterate over candidate debug images. 1872 * Keep track of "interesting" ones (those which have a symtab, dynsym, 1873 * and/or opd section) for processing. 1874 */ 1875 for (i = 0; i < DSO_BINARY_TYPE__SYMTAB_CNT; i++) { 1876 struct symsrc *ss = &ss_[ss_pos]; 1877 bool next_slot = false; 1878 bool is_reg; 1879 bool nsexit; 1880 int bfdrc = -1; 1881 int sirc = -1; 1882 1883 enum dso_binary_type symtab_type = binary_type_symtab[i]; 1884 1885 nsexit = (symtab_type == DSO_BINARY_TYPE__BUILD_ID_CACHE || 1886 symtab_type == DSO_BINARY_TYPE__BUILD_ID_CACHE_DEBUGINFO); 1887 1888 if (!dso__is_compatible_symtab_type(dso, kmod, symtab_type)) 1889 continue; 1890 1891 if (dso__read_binary_type_filename(dso, symtab_type, 1892 root_dir, name, PATH_MAX)) 1893 continue; 1894 1895 if (nsexit) 1896 nsinfo__mountns_exit(&nsc); 1897 1898 is_reg = is_regular_file(name); 1899 if (!is_reg && errno == ENOENT && dso__nsinfo(dso)) { 1900 char *new_name = dso__filename_with_chroot(dso, name); 1901 if (new_name) { 1902 is_reg = is_regular_file(new_name); 1903 strlcpy(name, new_name, PATH_MAX); 1904 free(new_name); 1905 } 1906 } 1907 1908 #ifdef HAVE_LIBBFD_SUPPORT 1909 if (is_reg) 1910 bfdrc = dso__load_bfd_symbols(dso, name); 1911 #endif 1912 if (is_reg && bfdrc < 0) 1913 sirc = symsrc__init(ss, dso, name, symtab_type); 1914 1915 if (nsexit) 1916 nsinfo__mountns_enter(dso__nsinfo(dso), &nsc); 1917 1918 if (bfdrc == 0) { 1919 ret = 0; 1920 break; 1921 } 1922 1923 if (!is_reg || sirc < 0) 1924 continue; 1925 1926 if (!syms_ss && symsrc__has_symtab(ss)) { 1927 syms_ss = ss; 1928 next_slot = true; 1929 if (!dso__symsrc_filename(dso)) 1930 dso__set_symsrc_filename(dso, strdup(name)); 1931 } 1932 1933 if (!runtime_ss && symsrc__possibly_runtime(ss)) { 1934 runtime_ss = ss; 1935 next_slot = true; 1936 } 1937 1938 if (next_slot) { 1939 ss_pos++; 1940 1941 if (dso__binary_type(dso) == DSO_BINARY_TYPE__NOT_FOUND) 1942 dso__set_binary_type(dso, symtab_type); 1943 1944 if (syms_ss && runtime_ss) 1945 break; 1946 } else { 1947 symsrc__destroy(ss); 1948 } 1949 1950 } 1951 1952 if (!runtime_ss && !syms_ss) 1953 goto out_free; 1954 1955 if (runtime_ss && !syms_ss) { 1956 syms_ss = runtime_ss; 1957 } 1958 1959 /* We'll have to hope for the best */ 1960 if (!runtime_ss && syms_ss) 1961 runtime_ss = syms_ss; 1962 1963 if (syms_ss) 1964 ret = dso__load_sym(dso, map, syms_ss, runtime_ss, kmod); 1965 else 1966 ret = -1; 1967 1968 if (ret > 0) { 1969 int nr_plt; 1970 1971 nr_plt = dso__synthesize_plt_symbols(dso, runtime_ss); 1972 if (nr_plt > 0) 1973 ret += nr_plt; 1974 } 1975 1976 for (; ss_pos > 0; ss_pos--) 1977 symsrc__destroy(&ss_[ss_pos - 1]); 1978 out_free: 1979 free(name); 1980 if (ret < 0 && strstr(dso__name(dso), " (deleted)") != NULL) 1981 ret = 0; 1982 out: 1983 dso__set_loaded(dso); 1984 mutex_unlock(dso__lock(dso)); 1985 nsinfo__mountns_exit(&nsc); 1986 1987 return ret; 1988 } 1989 1990 /* 1991 * Always takes ownership of vmlinux when vmlinux_allocated == true, even if 1992 * it returns an error. 1993 */ 1994 int dso__load_vmlinux(struct dso *dso, struct map *map, 1995 const char *vmlinux, bool vmlinux_allocated) 1996 { 1997 int err = -1; 1998 struct symsrc ss; 1999 char symfs_vmlinux[PATH_MAX]; 2000 enum dso_binary_type symtab_type; 2001 2002 if (vmlinux[0] == '/') 2003 snprintf(symfs_vmlinux, sizeof(symfs_vmlinux), "%s", vmlinux); 2004 else 2005 symbol__join_symfs(symfs_vmlinux, vmlinux); 2006 2007 if (dso__kernel(dso) == DSO_SPACE__KERNEL_GUEST) 2008 symtab_type = DSO_BINARY_TYPE__GUEST_VMLINUX; 2009 else 2010 symtab_type = DSO_BINARY_TYPE__VMLINUX; 2011 2012 if (symsrc__init(&ss, dso, symfs_vmlinux, symtab_type)) { 2013 if (vmlinux_allocated) 2014 free((char *) vmlinux); 2015 return -1; 2016 } 2017 2018 /* 2019 * dso__load_sym() may copy 'dso' which will result in the copies having 2020 * an incorrect long name unless we set it here first. 2021 */ 2022 dso__set_long_name(dso, vmlinux, vmlinux_allocated); 2023 if (dso__kernel(dso) == DSO_SPACE__KERNEL_GUEST) 2024 dso__set_binary_type(dso, DSO_BINARY_TYPE__GUEST_VMLINUX); 2025 else 2026 dso__set_binary_type(dso, DSO_BINARY_TYPE__VMLINUX); 2027 2028 err = dso__load_sym(dso, map, &ss, &ss, 0); 2029 symsrc__destroy(&ss); 2030 2031 if (err > 0) { 2032 dso__set_loaded(dso); 2033 pr_debug("Using %s for symbols\n", symfs_vmlinux); 2034 } 2035 2036 return err; 2037 } 2038 2039 int dso__load_vmlinux_path(struct dso *dso, struct map *map) 2040 { 2041 int i, err = 0; 2042 char *filename = NULL; 2043 2044 pr_debug("Looking at the vmlinux_path (%d entries long)\n", 2045 vmlinux_path__nr_entries + 1); 2046 2047 for (i = 0; i < vmlinux_path__nr_entries; ++i) { 2048 err = dso__load_vmlinux(dso, map, vmlinux_path[i], false); 2049 if (err > 0) 2050 goto out; 2051 } 2052 2053 if (!symbol_conf.ignore_vmlinux_buildid) 2054 filename = dso__build_id_filename(dso, NULL, 0, false); 2055 if (filename != NULL) { 2056 err = dso__load_vmlinux(dso, map, filename, true); 2057 if (err > 0) 2058 goto out; 2059 } 2060 out: 2061 return err; 2062 } 2063 2064 static bool visible_dir_filter(const char *name, struct dirent *d) 2065 { 2066 if (d->d_type != DT_DIR) 2067 return false; 2068 return lsdir_no_dot_filter(name, d); 2069 } 2070 2071 static int find_matching_kcore(struct map *map, char *dir, size_t dir_sz) 2072 { 2073 char kallsyms_filename[PATH_MAX]; 2074 int ret = -1; 2075 struct strlist *dirs; 2076 struct str_node *nd; 2077 2078 dirs = lsdir(dir, visible_dir_filter); 2079 if (!dirs) 2080 return -1; 2081 2082 strlist__for_each_entry(nd, dirs) { 2083 scnprintf(kallsyms_filename, sizeof(kallsyms_filename), 2084 "%s/%s/kallsyms", dir, nd->s); 2085 if (!validate_kcore_addresses(kallsyms_filename, map)) { 2086 strlcpy(dir, kallsyms_filename, dir_sz); 2087 ret = 0; 2088 break; 2089 } 2090 } 2091 2092 strlist__delete(dirs); 2093 2094 return ret; 2095 } 2096 2097 /* 2098 * Use open(O_RDONLY) to check readability directly instead of access(R_OK) 2099 * since access(R_OK) only checks with real UID/GID but open() use effective 2100 * UID/GID and actual capabilities (e.g. /proc/kcore requires CAP_SYS_RAWIO). 2101 */ 2102 static bool filename__readable(const char *file) 2103 { 2104 int fd = open(file, O_RDONLY); 2105 if (fd < 0) 2106 return false; 2107 close(fd); 2108 return true; 2109 } 2110 2111 static char *dso__find_kallsyms(struct dso *dso, struct map *map) 2112 { 2113 struct build_id bid; 2114 char sbuild_id[SBUILD_ID_SIZE]; 2115 bool is_host = false; 2116 char path[PATH_MAX]; 2117 2118 if (!dso__has_build_id(dso)) { 2119 /* 2120 * Last resort, if we don't have a build-id and couldn't find 2121 * any vmlinux file, try the running kernel kallsyms table. 2122 */ 2123 goto proc_kallsyms; 2124 } 2125 2126 if (sysfs__read_build_id("/sys/kernel/notes", &bid) == 0) 2127 is_host = dso__build_id_equal(dso, &bid); 2128 2129 /* Try a fast path for /proc/kallsyms if possible */ 2130 if (is_host) { 2131 /* 2132 * Do not check the build-id cache, unless we know we cannot use 2133 * /proc/kcore or module maps don't match to /proc/kallsyms. 2134 * To check readability of /proc/kcore, do not use access(R_OK) 2135 * since /proc/kcore requires CAP_SYS_RAWIO to read and access 2136 * can't check it. 2137 */ 2138 if (filename__readable("/proc/kcore") && 2139 !validate_kcore_addresses("/proc/kallsyms", map)) 2140 goto proc_kallsyms; 2141 } 2142 2143 build_id__sprintf(dso__bid(dso), sbuild_id); 2144 2145 /* Find kallsyms in build-id cache with kcore */ 2146 scnprintf(path, sizeof(path), "%s/%s/%s", 2147 buildid_dir, DSO__NAME_KCORE, sbuild_id); 2148 2149 if (!find_matching_kcore(map, path, sizeof(path))) 2150 return strdup(path); 2151 2152 /* Use current /proc/kallsyms if possible */ 2153 if (is_host) { 2154 proc_kallsyms: 2155 return strdup("/proc/kallsyms"); 2156 } 2157 2158 /* Finally, find a cache of kallsyms */ 2159 if (!build_id_cache__kallsyms_path(sbuild_id, path, sizeof(path))) { 2160 pr_err("No kallsyms or vmlinux with build-id %s was found\n", 2161 sbuild_id); 2162 return NULL; 2163 } 2164 2165 return strdup(path); 2166 } 2167 2168 static int dso__load_kernel_sym(struct dso *dso, struct map *map) 2169 { 2170 int err; 2171 const char *kallsyms_filename = NULL; 2172 char *kallsyms_allocated_filename = NULL; 2173 char *filename = NULL; 2174 2175 /* 2176 * Step 1: if the user specified a kallsyms or vmlinux filename, use 2177 * it and only it, reporting errors to the user if it cannot be used. 2178 * 2179 * For instance, try to analyse an ARM perf.data file _without_ a 2180 * build-id, or if the user specifies the wrong path to the right 2181 * vmlinux file, obviously we can't fallback to another vmlinux (a 2182 * x86_86 one, on the machine where analysis is being performed, say), 2183 * or worse, /proc/kallsyms. 2184 * 2185 * If the specified file _has_ a build-id and there is a build-id 2186 * section in the perf.data file, we will still do the expected 2187 * validation in dso__load_vmlinux and will bail out if they don't 2188 * match. 2189 */ 2190 if (symbol_conf.kallsyms_name != NULL) { 2191 kallsyms_filename = symbol_conf.kallsyms_name; 2192 goto do_kallsyms; 2193 } 2194 2195 if (!symbol_conf.ignore_vmlinux && symbol_conf.vmlinux_name != NULL) { 2196 return dso__load_vmlinux(dso, map, symbol_conf.vmlinux_name, false); 2197 } 2198 2199 /* 2200 * Before checking on common vmlinux locations, check if it's 2201 * stored as standard build id binary (not kallsyms) under 2202 * .debug cache. 2203 */ 2204 if (!symbol_conf.ignore_vmlinux_buildid) 2205 filename = __dso__build_id_filename(dso, NULL, 0, false, false); 2206 if (filename != NULL) { 2207 err = dso__load_vmlinux(dso, map, filename, true); 2208 if (err > 0) 2209 return err; 2210 } 2211 2212 if (!symbol_conf.ignore_vmlinux && vmlinux_path != NULL) { 2213 err = dso__load_vmlinux_path(dso, map); 2214 if (err > 0) 2215 return err; 2216 } 2217 2218 /* do not try local files if a symfs was given */ 2219 if (symbol_conf.symfs[0] != 0) 2220 return -1; 2221 2222 kallsyms_allocated_filename = dso__find_kallsyms(dso, map); 2223 if (!kallsyms_allocated_filename) 2224 return -1; 2225 2226 kallsyms_filename = kallsyms_allocated_filename; 2227 2228 do_kallsyms: 2229 err = dso__load_kallsyms(dso, kallsyms_filename, map); 2230 if (err > 0) 2231 pr_debug("Using %s for symbols\n", kallsyms_filename); 2232 free(kallsyms_allocated_filename); 2233 2234 if (err > 0 && !dso__is_kcore(dso)) { 2235 dso__set_binary_type(dso, DSO_BINARY_TYPE__KALLSYMS); 2236 dso__set_long_name(dso, DSO__NAME_KALLSYMS, false); 2237 map__fixup_start(map); 2238 map__fixup_end(map); 2239 } 2240 2241 return err; 2242 } 2243 2244 static int dso__load_guest_kernel_sym(struct dso *dso, struct map *map) 2245 { 2246 int err; 2247 const char *kallsyms_filename; 2248 struct machine *machine = maps__machine(map__kmaps(map)); 2249 char path[PATH_MAX]; 2250 2251 if (machine->kallsyms_filename) { 2252 kallsyms_filename = machine->kallsyms_filename; 2253 } else if (machine__is_default_guest(machine)) { 2254 /* 2255 * if the user specified a vmlinux filename, use it and only 2256 * it, reporting errors to the user if it cannot be used. 2257 * Or use file guest_kallsyms inputted by user on commandline 2258 */ 2259 if (symbol_conf.default_guest_vmlinux_name != NULL) { 2260 err = dso__load_vmlinux(dso, map, 2261 symbol_conf.default_guest_vmlinux_name, 2262 false); 2263 return err; 2264 } 2265 2266 kallsyms_filename = symbol_conf.default_guest_kallsyms; 2267 if (!kallsyms_filename) 2268 return -1; 2269 } else { 2270 sprintf(path, "%s/proc/kallsyms", machine->root_dir); 2271 kallsyms_filename = path; 2272 } 2273 2274 err = dso__load_kallsyms(dso, kallsyms_filename, map); 2275 if (err > 0) 2276 pr_debug("Using %s for symbols\n", kallsyms_filename); 2277 if (err > 0 && !dso__is_kcore(dso)) { 2278 dso__set_binary_type(dso, DSO_BINARY_TYPE__GUEST_KALLSYMS); 2279 dso__set_long_name(dso, machine->mmap_name, false); 2280 map__fixup_start(map); 2281 map__fixup_end(map); 2282 } 2283 2284 return err; 2285 } 2286 2287 static void vmlinux_path__exit(void) 2288 { 2289 while (--vmlinux_path__nr_entries >= 0) 2290 zfree(&vmlinux_path[vmlinux_path__nr_entries]); 2291 vmlinux_path__nr_entries = 0; 2292 2293 zfree(&vmlinux_path); 2294 } 2295 2296 static const char * const vmlinux_paths[] = { 2297 "vmlinux", 2298 "/boot/vmlinux" 2299 }; 2300 2301 static const char * const vmlinux_paths_upd[] = { 2302 "/boot/vmlinux-%s", 2303 "/usr/lib/debug/boot/vmlinux-%s", 2304 "/lib/modules/%s/build/vmlinux", 2305 "/usr/lib/debug/lib/modules/%s/vmlinux", 2306 "/usr/lib/debug/boot/vmlinux-%s.debug" 2307 }; 2308 2309 static int vmlinux_path__add(const char *new_entry) 2310 { 2311 vmlinux_path[vmlinux_path__nr_entries] = strdup(new_entry); 2312 if (vmlinux_path[vmlinux_path__nr_entries] == NULL) 2313 return -1; 2314 ++vmlinux_path__nr_entries; 2315 2316 return 0; 2317 } 2318 2319 static int vmlinux_path__init(struct perf_env *env) 2320 { 2321 struct utsname uts; 2322 char bf[PATH_MAX]; 2323 char *kernel_version; 2324 unsigned int i; 2325 2326 vmlinux_path = malloc(sizeof(char *) * (ARRAY_SIZE(vmlinux_paths) + 2327 ARRAY_SIZE(vmlinux_paths_upd))); 2328 if (vmlinux_path == NULL) 2329 return -1; 2330 2331 for (i = 0; i < ARRAY_SIZE(vmlinux_paths); i++) 2332 if (vmlinux_path__add(vmlinux_paths[i]) < 0) 2333 goto out_fail; 2334 2335 /* only try kernel version if no symfs was given */ 2336 if (symbol_conf.symfs[0] != 0) 2337 return 0; 2338 2339 if (env) { 2340 kernel_version = env->os_release; 2341 } else { 2342 if (uname(&uts) < 0) 2343 goto out_fail; 2344 2345 kernel_version = uts.release; 2346 } 2347 2348 for (i = 0; i < ARRAY_SIZE(vmlinux_paths_upd); i++) { 2349 snprintf(bf, sizeof(bf), vmlinux_paths_upd[i], kernel_version); 2350 if (vmlinux_path__add(bf) < 0) 2351 goto out_fail; 2352 } 2353 2354 return 0; 2355 2356 out_fail: 2357 vmlinux_path__exit(); 2358 return -1; 2359 } 2360 2361 int setup_list(struct strlist **list, const char *list_str, 2362 const char *list_name) 2363 { 2364 if (list_str == NULL) 2365 return 0; 2366 2367 *list = strlist__new(list_str, NULL); 2368 if (!*list) { 2369 pr_err("problems parsing %s list\n", list_name); 2370 return -1; 2371 } 2372 2373 symbol_conf.has_filter = true; 2374 return 0; 2375 } 2376 2377 int setup_intlist(struct intlist **list, const char *list_str, 2378 const char *list_name) 2379 { 2380 if (list_str == NULL) 2381 return 0; 2382 2383 *list = intlist__new(list_str); 2384 if (!*list) { 2385 pr_err("problems parsing %s list\n", list_name); 2386 return -1; 2387 } 2388 return 0; 2389 } 2390 2391 static int setup_addrlist(struct intlist **addr_list, struct strlist *sym_list) 2392 { 2393 struct str_node *pos, *tmp; 2394 unsigned long val; 2395 char *sep; 2396 const char *end; 2397 int i = 0, err; 2398 2399 *addr_list = intlist__new(NULL); 2400 if (!*addr_list) 2401 return -1; 2402 2403 strlist__for_each_entry_safe(pos, tmp, sym_list) { 2404 errno = 0; 2405 val = strtoul(pos->s, &sep, 16); 2406 if (errno || (sep == pos->s)) 2407 continue; 2408 2409 if (*sep != '\0') { 2410 end = pos->s + strlen(pos->s) - 1; 2411 while (end >= sep && isspace(*end)) 2412 end--; 2413 2414 if (end >= sep) 2415 continue; 2416 } 2417 2418 err = intlist__add(*addr_list, val); 2419 if (err) 2420 break; 2421 2422 strlist__remove(sym_list, pos); 2423 i++; 2424 } 2425 2426 if (i == 0) { 2427 intlist__delete(*addr_list); 2428 *addr_list = NULL; 2429 } 2430 2431 return 0; 2432 } 2433 2434 static bool symbol__read_kptr_restrict(void) 2435 { 2436 bool value = false; 2437 FILE *fp = fopen("/proc/sys/kernel/kptr_restrict", "r"); 2438 bool used_root; 2439 bool cap_syslog = perf_cap__capable(CAP_SYSLOG, &used_root); 2440 2441 if (fp != NULL) { 2442 char line[8]; 2443 2444 if (fgets(line, sizeof(line), fp) != NULL) 2445 value = cap_syslog ? (atoi(line) >= 2) : (atoi(line) != 0); 2446 2447 fclose(fp); 2448 } 2449 2450 /* Per kernel/kallsyms.c: 2451 * we also restrict when perf_event_paranoid > 1 w/o CAP_SYSLOG 2452 */ 2453 if (perf_event_paranoid() > 1 && !cap_syslog) 2454 value = true; 2455 2456 return value; 2457 } 2458 2459 int symbol__annotation_init(void) 2460 { 2461 if (symbol_conf.init_annotation) 2462 return 0; 2463 2464 if (symbol_conf.initialized) { 2465 pr_err("Annotation needs to be init before symbol__init()\n"); 2466 return -1; 2467 } 2468 2469 symbol_conf.priv_size += sizeof(struct annotation); 2470 symbol_conf.init_annotation = true; 2471 return 0; 2472 } 2473 2474 int symbol__init(struct perf_env *env) 2475 { 2476 const char *symfs; 2477 2478 if (symbol_conf.initialized) 2479 return 0; 2480 2481 symbol_conf.priv_size = PERF_ALIGN(symbol_conf.priv_size, sizeof(u64)); 2482 2483 symbol__elf_init(); 2484 2485 if (symbol_conf.try_vmlinux_path && vmlinux_path__init(env) < 0) 2486 return -1; 2487 2488 if (symbol_conf.field_sep && *symbol_conf.field_sep == '.') { 2489 pr_err("'.' is the only non valid --field-separator argument\n"); 2490 return -1; 2491 } 2492 2493 if (setup_list(&symbol_conf.dso_list, 2494 symbol_conf.dso_list_str, "dso") < 0) 2495 return -1; 2496 2497 if (setup_list(&symbol_conf.comm_list, 2498 symbol_conf.comm_list_str, "comm") < 0) 2499 goto out_free_dso_list; 2500 2501 if (setup_intlist(&symbol_conf.pid_list, 2502 symbol_conf.pid_list_str, "pid") < 0) 2503 goto out_free_comm_list; 2504 2505 if (setup_intlist(&symbol_conf.tid_list, 2506 symbol_conf.tid_list_str, "tid") < 0) 2507 goto out_free_pid_list; 2508 2509 if (setup_list(&symbol_conf.sym_list, 2510 symbol_conf.sym_list_str, "symbol") < 0) 2511 goto out_free_tid_list; 2512 2513 if (symbol_conf.sym_list && 2514 setup_addrlist(&symbol_conf.addr_list, symbol_conf.sym_list) < 0) 2515 goto out_free_sym_list; 2516 2517 if (setup_list(&symbol_conf.bt_stop_list, 2518 symbol_conf.bt_stop_list_str, "symbol") < 0) 2519 goto out_free_sym_list; 2520 2521 /* 2522 * A path to symbols of "/" is identical to "" 2523 * reset here for simplicity. 2524 */ 2525 symfs = realpath(symbol_conf.symfs, NULL); 2526 if (symfs == NULL) 2527 symfs = symbol_conf.symfs; 2528 if (strcmp(symfs, "/") == 0) 2529 symbol_conf.symfs = ""; 2530 if (symfs != symbol_conf.symfs) 2531 free((void *)symfs); 2532 2533 symbol_conf.kptr_restrict = symbol__read_kptr_restrict(); 2534 2535 symbol_conf.initialized = true; 2536 return 0; 2537 2538 out_free_sym_list: 2539 strlist__delete(symbol_conf.sym_list); 2540 intlist__delete(symbol_conf.addr_list); 2541 out_free_tid_list: 2542 intlist__delete(symbol_conf.tid_list); 2543 out_free_pid_list: 2544 intlist__delete(symbol_conf.pid_list); 2545 out_free_comm_list: 2546 strlist__delete(symbol_conf.comm_list); 2547 out_free_dso_list: 2548 strlist__delete(symbol_conf.dso_list); 2549 return -1; 2550 } 2551 2552 void symbol__exit(void) 2553 { 2554 if (!symbol_conf.initialized) 2555 return; 2556 strlist__delete(symbol_conf.bt_stop_list); 2557 strlist__delete(symbol_conf.sym_list); 2558 strlist__delete(symbol_conf.dso_list); 2559 strlist__delete(symbol_conf.comm_list); 2560 intlist__delete(symbol_conf.tid_list); 2561 intlist__delete(symbol_conf.pid_list); 2562 intlist__delete(symbol_conf.addr_list); 2563 vmlinux_path__exit(); 2564 symbol_conf.sym_list = symbol_conf.dso_list = symbol_conf.comm_list = NULL; 2565 symbol_conf.bt_stop_list = NULL; 2566 symbol_conf.initialized = false; 2567 } 2568 2569 int symbol__config_symfs(const struct option *opt __maybe_unused, 2570 const char *dir, int unset __maybe_unused) 2571 { 2572 char *bf = NULL; 2573 int ret; 2574 2575 symbol_conf.symfs = strdup(dir); 2576 if (symbol_conf.symfs == NULL) 2577 return -ENOMEM; 2578 2579 /* skip the locally configured cache if a symfs is given, and 2580 * config buildid dir to symfs/.debug 2581 */ 2582 ret = asprintf(&bf, "%s/%s", dir, ".debug"); 2583 if (ret < 0) 2584 return -ENOMEM; 2585 2586 set_buildid_dir(bf); 2587 2588 free(bf); 2589 return 0; 2590 } 2591 2592 /* 2593 * Checks that user supplied symbol kernel files are accessible because 2594 * the default mechanism for accessing elf files fails silently. i.e. if 2595 * debug syms for a build ID aren't found perf carries on normally. When 2596 * they are user supplied we should assume that the user doesn't want to 2597 * silently fail. 2598 */ 2599 int symbol__validate_sym_arguments(void) 2600 { 2601 if (symbol_conf.vmlinux_name && 2602 access(symbol_conf.vmlinux_name, R_OK)) { 2603 pr_err("Invalid file: %s\n", symbol_conf.vmlinux_name); 2604 return -EINVAL; 2605 } 2606 if (symbol_conf.kallsyms_name && 2607 access(symbol_conf.kallsyms_name, R_OK)) { 2608 pr_err("Invalid file: %s\n", symbol_conf.kallsyms_name); 2609 return -EINVAL; 2610 } 2611 return 0; 2612 } 2613