tools/perf/util/symbol.c

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