xref: /linux/tools/perf/util/symbol.c (revision ca853314e78b0a65c20b6a889a23c31f918d4aa2)
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 void dso__delete_symbol(struct dso *dso, struct symbol *sym)
519 {
520 	rb_erase_cached(&sym->rb_node, &dso->symbols);
521 	symbol__delete(sym);
522 	dso__reset_find_symbol_cache(dso);
523 }
524 
525 struct symbol *dso__find_symbol(struct dso *dso, u64 addr)
526 {
527 	if (dso->last_find_result.addr != addr || dso->last_find_result.symbol == NULL) {
528 		dso->last_find_result.addr   = addr;
529 		dso->last_find_result.symbol = symbols__find(&dso->symbols, addr);
530 	}
531 
532 	return dso->last_find_result.symbol;
533 }
534 
535 struct symbol *dso__first_symbol(struct dso *dso)
536 {
537 	return symbols__first(&dso->symbols);
538 }
539 
540 struct symbol *dso__last_symbol(struct dso *dso)
541 {
542 	return symbols__last(&dso->symbols);
543 }
544 
545 struct symbol *dso__next_symbol(struct symbol *sym)
546 {
547 	return symbols__next(sym);
548 }
549 
550 struct symbol *symbol__next_by_name(struct symbol *sym)
551 {
552 	struct symbol_name_rb_node *s = container_of(sym, struct symbol_name_rb_node, sym);
553 	struct rb_node *n = rb_next(&s->rb_node);
554 
555 	return n ? &rb_entry(n, struct symbol_name_rb_node, rb_node)->sym : NULL;
556 }
557 
558  /*
559   * Returns first symbol that matched with @name.
560   */
561 struct symbol *dso__find_symbol_by_name(struct dso *dso, const char *name)
562 {
563 	struct symbol *s = symbols__find_by_name(&dso->symbol_names, name,
564 						 SYMBOL_TAG_INCLUDE__NONE);
565 	if (!s)
566 		s = symbols__find_by_name(&dso->symbol_names, name,
567 					  SYMBOL_TAG_INCLUDE__DEFAULT_ONLY);
568 	return s;
569 }
570 
571 void dso__sort_by_name(struct dso *dso)
572 {
573 	dso__set_sorted_by_name(dso);
574 	return symbols__sort_by_name(&dso->symbol_names, &dso->symbols);
575 }
576 
577 /*
578  * While we find nice hex chars, build a long_val.
579  * Return number of chars processed.
580  */
581 static int hex2u64(const char *ptr, u64 *long_val)
582 {
583 	char *p;
584 
585 	*long_val = strtoull(ptr, &p, 16);
586 
587 	return p - ptr;
588 }
589 
590 
591 int modules__parse(const char *filename, void *arg,
592 		   int (*process_module)(void *arg, const char *name,
593 					 u64 start, u64 size))
594 {
595 	char *line = NULL;
596 	size_t n;
597 	FILE *file;
598 	int err = 0;
599 
600 	file = fopen(filename, "r");
601 	if (file == NULL)
602 		return -1;
603 
604 	while (1) {
605 		char name[PATH_MAX];
606 		u64 start, size;
607 		char *sep, *endptr;
608 		ssize_t line_len;
609 
610 		line_len = getline(&line, &n, file);
611 		if (line_len < 0) {
612 			if (feof(file))
613 				break;
614 			err = -1;
615 			goto out;
616 		}
617 
618 		if (!line) {
619 			err = -1;
620 			goto out;
621 		}
622 
623 		line[--line_len] = '\0'; /* \n */
624 
625 		sep = strrchr(line, 'x');
626 		if (sep == NULL)
627 			continue;
628 
629 		hex2u64(sep + 1, &start);
630 
631 		sep = strchr(line, ' ');
632 		if (sep == NULL)
633 			continue;
634 
635 		*sep = '\0';
636 
637 		scnprintf(name, sizeof(name), "[%s]", line);
638 
639 		size = strtoul(sep + 1, &endptr, 0);
640 		if (*endptr != ' ' && *endptr != '\t')
641 			continue;
642 
643 		err = process_module(arg, name, start, size);
644 		if (err)
645 			break;
646 	}
647 out:
648 	free(line);
649 	fclose(file);
650 	return err;
651 }
652 
653 /*
654  * These are symbols in the kernel image, so make sure that
655  * sym is from a kernel DSO.
656  */
657 static bool symbol__is_idle(const char *name)
658 {
659 	const char * const idle_symbols[] = {
660 		"acpi_idle_do_entry",
661 		"acpi_processor_ffh_cstate_enter",
662 		"arch_cpu_idle",
663 		"cpu_idle",
664 		"cpu_startup_entry",
665 		"idle_cpu",
666 		"intel_idle",
667 		"default_idle",
668 		"native_safe_halt",
669 		"enter_idle",
670 		"exit_idle",
671 		"mwait_idle",
672 		"mwait_idle_with_hints",
673 		"mwait_idle_with_hints.constprop.0",
674 		"poll_idle",
675 		"ppc64_runlatch_off",
676 		"pseries_dedicated_idle_sleep",
677 		"psw_idle",
678 		"psw_idle_exit",
679 		NULL
680 	};
681 	int i;
682 	static struct strlist *idle_symbols_list;
683 
684 	if (idle_symbols_list)
685 		return strlist__has_entry(idle_symbols_list, name);
686 
687 	idle_symbols_list = strlist__new(NULL, NULL);
688 
689 	for (i = 0; idle_symbols[i]; i++)
690 		strlist__add(idle_symbols_list, idle_symbols[i]);
691 
692 	return strlist__has_entry(idle_symbols_list, name);
693 }
694 
695 static int map__process_kallsym_symbol(void *arg, const char *name,
696 				       char type, u64 start)
697 {
698 	struct symbol *sym;
699 	struct dso *dso = arg;
700 	struct rb_root_cached *root = &dso->symbols;
701 
702 	if (!symbol_type__filter(type))
703 		return 0;
704 
705 	/*
706 	 * module symbols are not sorted so we add all
707 	 * symbols, setting length to 0, and rely on
708 	 * symbols__fixup_end() to fix it up.
709 	 */
710 	sym = symbol__new(start, 0, kallsyms2elf_binding(type), kallsyms2elf_type(type), name);
711 	if (sym == NULL)
712 		return -ENOMEM;
713 	/*
714 	 * We will pass the symbols to the filter later, in
715 	 * map__split_kallsyms, when we have split the maps per module
716 	 */
717 	__symbols__insert(root, sym, !strchr(name, '['));
718 
719 	return 0;
720 }
721 
722 /*
723  * Loads the function entries in /proc/kallsyms into kernel_map->dso,
724  * so that we can in the next step set the symbol ->end address and then
725  * call kernel_maps__split_kallsyms.
726  */
727 static int dso__load_all_kallsyms(struct dso *dso, const char *filename)
728 {
729 	return kallsyms__parse(filename, dso, map__process_kallsym_symbol);
730 }
731 
732 static int maps__split_kallsyms_for_kcore(struct maps *kmaps, struct dso *dso)
733 {
734 	struct map *curr_map;
735 	struct symbol *pos;
736 	int count = 0;
737 	struct rb_root_cached old_root = dso->symbols;
738 	struct rb_root_cached *root = &dso->symbols;
739 	struct rb_node *next = rb_first_cached(root);
740 
741 	if (!kmaps)
742 		return -1;
743 
744 	*root = RB_ROOT_CACHED;
745 
746 	while (next) {
747 		char *module;
748 
749 		pos = rb_entry(next, struct symbol, rb_node);
750 		next = rb_next(&pos->rb_node);
751 
752 		rb_erase_cached(&pos->rb_node, &old_root);
753 		RB_CLEAR_NODE(&pos->rb_node);
754 		module = strchr(pos->name, '\t');
755 		if (module)
756 			*module = '\0';
757 
758 		curr_map = maps__find(kmaps, pos->start);
759 
760 		if (!curr_map) {
761 			symbol__delete(pos);
762 			continue;
763 		}
764 
765 		pos->start -= curr_map->start - curr_map->pgoff;
766 		if (pos->end > curr_map->end)
767 			pos->end = curr_map->end;
768 		if (pos->end)
769 			pos->end -= curr_map->start - curr_map->pgoff;
770 		symbols__insert(&curr_map->dso->symbols, pos);
771 		++count;
772 	}
773 
774 	/* Symbols have been adjusted */
775 	dso->adjust_symbols = 1;
776 
777 	return count;
778 }
779 
780 /*
781  * Split the symbols into maps, making sure there are no overlaps, i.e. the
782  * kernel range is broken in several maps, named [kernel].N, as we don't have
783  * the original ELF section names vmlinux have.
784  */
785 static int maps__split_kallsyms(struct maps *kmaps, struct dso *dso, u64 delta,
786 				struct map *initial_map)
787 {
788 	struct machine *machine;
789 	struct map *curr_map = initial_map;
790 	struct symbol *pos;
791 	int count = 0, moved = 0;
792 	struct rb_root_cached *root = &dso->symbols;
793 	struct rb_node *next = rb_first_cached(root);
794 	int kernel_range = 0;
795 	bool x86_64;
796 
797 	if (!kmaps)
798 		return -1;
799 
800 	machine = kmaps->machine;
801 
802 	x86_64 = machine__is(machine, "x86_64");
803 
804 	while (next) {
805 		char *module;
806 
807 		pos = rb_entry(next, struct symbol, rb_node);
808 		next = rb_next(&pos->rb_node);
809 
810 		module = strchr(pos->name, '\t');
811 		if (module) {
812 			if (!symbol_conf.use_modules)
813 				goto discard_symbol;
814 
815 			*module++ = '\0';
816 
817 			if (strcmp(curr_map->dso->short_name, module)) {
818 				if (curr_map != initial_map &&
819 				    dso->kernel == DSO_SPACE__KERNEL_GUEST &&
820 				    machine__is_default_guest(machine)) {
821 					/*
822 					 * We assume all symbols of a module are
823 					 * continuous in * kallsyms, so curr_map
824 					 * points to a module and all its
825 					 * symbols are in its kmap. Mark it as
826 					 * loaded.
827 					 */
828 					dso__set_loaded(curr_map->dso);
829 				}
830 
831 				curr_map = maps__find_by_name(kmaps, module);
832 				if (curr_map == NULL) {
833 					pr_debug("%s/proc/{kallsyms,modules} "
834 					         "inconsistency while looking "
835 						 "for \"%s\" module!\n",
836 						 machine->root_dir, module);
837 					curr_map = initial_map;
838 					goto discard_symbol;
839 				}
840 
841 				if (curr_map->dso->loaded &&
842 				    !machine__is_default_guest(machine))
843 					goto discard_symbol;
844 			}
845 			/*
846 			 * So that we look just like we get from .ko files,
847 			 * i.e. not prelinked, relative to initial_map->start.
848 			 */
849 			pos->start = curr_map->map_ip(curr_map, pos->start);
850 			pos->end   = curr_map->map_ip(curr_map, pos->end);
851 		} else if (x86_64 && is_entry_trampoline(pos->name)) {
852 			/*
853 			 * These symbols are not needed anymore since the
854 			 * trampoline maps refer to the text section and it's
855 			 * symbols instead. Avoid having to deal with
856 			 * relocations, and the assumption that the first symbol
857 			 * is the start of kernel text, by simply removing the
858 			 * symbols at this point.
859 			 */
860 			goto discard_symbol;
861 		} else if (curr_map != initial_map) {
862 			char dso_name[PATH_MAX];
863 			struct dso *ndso;
864 
865 			if (delta) {
866 				/* Kernel was relocated at boot time */
867 				pos->start -= delta;
868 				pos->end -= delta;
869 			}
870 
871 			if (count == 0) {
872 				curr_map = initial_map;
873 				goto add_symbol;
874 			}
875 
876 			if (dso->kernel == DSO_SPACE__KERNEL_GUEST)
877 				snprintf(dso_name, sizeof(dso_name),
878 					"[guest.kernel].%d",
879 					kernel_range++);
880 			else
881 				snprintf(dso_name, sizeof(dso_name),
882 					"[kernel].%d",
883 					kernel_range++);
884 
885 			ndso = dso__new(dso_name);
886 			if (ndso == NULL)
887 				return -1;
888 
889 			ndso->kernel = dso->kernel;
890 
891 			curr_map = map__new2(pos->start, ndso);
892 			if (curr_map == NULL) {
893 				dso__put(ndso);
894 				return -1;
895 			}
896 
897 			curr_map->map_ip = curr_map->unmap_ip = identity__map_ip;
898 			maps__insert(kmaps, curr_map);
899 			++kernel_range;
900 		} else if (delta) {
901 			/* Kernel was relocated at boot time */
902 			pos->start -= delta;
903 			pos->end -= delta;
904 		}
905 add_symbol:
906 		if (curr_map != initial_map) {
907 			rb_erase_cached(&pos->rb_node, root);
908 			symbols__insert(&curr_map->dso->symbols, pos);
909 			++moved;
910 		} else
911 			++count;
912 
913 		continue;
914 discard_symbol:
915 		rb_erase_cached(&pos->rb_node, root);
916 		symbol__delete(pos);
917 	}
918 
919 	if (curr_map != initial_map &&
920 	    dso->kernel == DSO_SPACE__KERNEL_GUEST &&
921 	    machine__is_default_guest(kmaps->machine)) {
922 		dso__set_loaded(curr_map->dso);
923 	}
924 
925 	return count + moved;
926 }
927 
928 bool symbol__restricted_filename(const char *filename,
929 				 const char *restricted_filename)
930 {
931 	bool restricted = false;
932 
933 	if (symbol_conf.kptr_restrict) {
934 		char *r = realpath(filename, NULL);
935 
936 		if (r != NULL) {
937 			restricted = strcmp(r, restricted_filename) == 0;
938 			free(r);
939 			return restricted;
940 		}
941 	}
942 
943 	return restricted;
944 }
945 
946 struct module_info {
947 	struct rb_node rb_node;
948 	char *name;
949 	u64 start;
950 };
951 
952 static void add_module(struct module_info *mi, struct rb_root *modules)
953 {
954 	struct rb_node **p = &modules->rb_node;
955 	struct rb_node *parent = NULL;
956 	struct module_info *m;
957 
958 	while (*p != NULL) {
959 		parent = *p;
960 		m = rb_entry(parent, struct module_info, rb_node);
961 		if (strcmp(mi->name, m->name) < 0)
962 			p = &(*p)->rb_left;
963 		else
964 			p = &(*p)->rb_right;
965 	}
966 	rb_link_node(&mi->rb_node, parent, p);
967 	rb_insert_color(&mi->rb_node, modules);
968 }
969 
970 static void delete_modules(struct rb_root *modules)
971 {
972 	struct module_info *mi;
973 	struct rb_node *next = rb_first(modules);
974 
975 	while (next) {
976 		mi = rb_entry(next, struct module_info, rb_node);
977 		next = rb_next(&mi->rb_node);
978 		rb_erase(&mi->rb_node, modules);
979 		zfree(&mi->name);
980 		free(mi);
981 	}
982 }
983 
984 static struct module_info *find_module(const char *name,
985 				       struct rb_root *modules)
986 {
987 	struct rb_node *n = modules->rb_node;
988 
989 	while (n) {
990 		struct module_info *m;
991 		int cmp;
992 
993 		m = rb_entry(n, struct module_info, rb_node);
994 		cmp = strcmp(name, m->name);
995 		if (cmp < 0)
996 			n = n->rb_left;
997 		else if (cmp > 0)
998 			n = n->rb_right;
999 		else
1000 			return m;
1001 	}
1002 
1003 	return NULL;
1004 }
1005 
1006 static int __read_proc_modules(void *arg, const char *name, u64 start,
1007 			       u64 size __maybe_unused)
1008 {
1009 	struct rb_root *modules = arg;
1010 	struct module_info *mi;
1011 
1012 	mi = zalloc(sizeof(struct module_info));
1013 	if (!mi)
1014 		return -ENOMEM;
1015 
1016 	mi->name = strdup(name);
1017 	mi->start = start;
1018 
1019 	if (!mi->name) {
1020 		free(mi);
1021 		return -ENOMEM;
1022 	}
1023 
1024 	add_module(mi, modules);
1025 
1026 	return 0;
1027 }
1028 
1029 static int read_proc_modules(const char *filename, struct rb_root *modules)
1030 {
1031 	if (symbol__restricted_filename(filename, "/proc/modules"))
1032 		return -1;
1033 
1034 	if (modules__parse(filename, modules, __read_proc_modules)) {
1035 		delete_modules(modules);
1036 		return -1;
1037 	}
1038 
1039 	return 0;
1040 }
1041 
1042 int compare_proc_modules(const char *from, const char *to)
1043 {
1044 	struct rb_root from_modules = RB_ROOT;
1045 	struct rb_root to_modules = RB_ROOT;
1046 	struct rb_node *from_node, *to_node;
1047 	struct module_info *from_m, *to_m;
1048 	int ret = -1;
1049 
1050 	if (read_proc_modules(from, &from_modules))
1051 		return -1;
1052 
1053 	if (read_proc_modules(to, &to_modules))
1054 		goto out_delete_from;
1055 
1056 	from_node = rb_first(&from_modules);
1057 	to_node = rb_first(&to_modules);
1058 	while (from_node) {
1059 		if (!to_node)
1060 			break;
1061 
1062 		from_m = rb_entry(from_node, struct module_info, rb_node);
1063 		to_m = rb_entry(to_node, struct module_info, rb_node);
1064 
1065 		if (from_m->start != to_m->start ||
1066 		    strcmp(from_m->name, to_m->name))
1067 			break;
1068 
1069 		from_node = rb_next(from_node);
1070 		to_node = rb_next(to_node);
1071 	}
1072 
1073 	if (!from_node && !to_node)
1074 		ret = 0;
1075 
1076 	delete_modules(&to_modules);
1077 out_delete_from:
1078 	delete_modules(&from_modules);
1079 
1080 	return ret;
1081 }
1082 
1083 static int do_validate_kcore_modules(const char *filename, struct maps *kmaps)
1084 {
1085 	struct rb_root modules = RB_ROOT;
1086 	struct map *old_map;
1087 	int err;
1088 
1089 	err = read_proc_modules(filename, &modules);
1090 	if (err)
1091 		return err;
1092 
1093 	maps__for_each_entry(kmaps, old_map) {
1094 		struct module_info *mi;
1095 
1096 		if (!__map__is_kmodule(old_map)) {
1097 			continue;
1098 		}
1099 
1100 		/* Module must be in memory at the same address */
1101 		mi = find_module(old_map->dso->short_name, &modules);
1102 		if (!mi || mi->start != old_map->start) {
1103 			err = -EINVAL;
1104 			goto out;
1105 		}
1106 	}
1107 out:
1108 	delete_modules(&modules);
1109 	return err;
1110 }
1111 
1112 /*
1113  * If kallsyms is referenced by name then we look for filename in the same
1114  * directory.
1115  */
1116 static bool filename_from_kallsyms_filename(char *filename,
1117 					    const char *base_name,
1118 					    const char *kallsyms_filename)
1119 {
1120 	char *name;
1121 
1122 	strcpy(filename, kallsyms_filename);
1123 	name = strrchr(filename, '/');
1124 	if (!name)
1125 		return false;
1126 
1127 	name += 1;
1128 
1129 	if (!strcmp(name, "kallsyms")) {
1130 		strcpy(name, base_name);
1131 		return true;
1132 	}
1133 
1134 	return false;
1135 }
1136 
1137 static int validate_kcore_modules(const char *kallsyms_filename,
1138 				  struct map *map)
1139 {
1140 	struct maps *kmaps = map__kmaps(map);
1141 	char modules_filename[PATH_MAX];
1142 
1143 	if (!kmaps)
1144 		return -EINVAL;
1145 
1146 	if (!filename_from_kallsyms_filename(modules_filename, "modules",
1147 					     kallsyms_filename))
1148 		return -EINVAL;
1149 
1150 	if (do_validate_kcore_modules(modules_filename, kmaps))
1151 		return -EINVAL;
1152 
1153 	return 0;
1154 }
1155 
1156 static int validate_kcore_addresses(const char *kallsyms_filename,
1157 				    struct map *map)
1158 {
1159 	struct kmap *kmap = map__kmap(map);
1160 
1161 	if (!kmap)
1162 		return -EINVAL;
1163 
1164 	if (kmap->ref_reloc_sym && kmap->ref_reloc_sym->name) {
1165 		u64 start;
1166 
1167 		if (kallsyms__get_function_start(kallsyms_filename,
1168 						 kmap->ref_reloc_sym->name, &start))
1169 			return -ENOENT;
1170 		if (start != kmap->ref_reloc_sym->addr)
1171 			return -EINVAL;
1172 	}
1173 
1174 	return validate_kcore_modules(kallsyms_filename, map);
1175 }
1176 
1177 struct kcore_mapfn_data {
1178 	struct dso *dso;
1179 	struct list_head maps;
1180 };
1181 
1182 static int kcore_mapfn(u64 start, u64 len, u64 pgoff, void *data)
1183 {
1184 	struct kcore_mapfn_data *md = data;
1185 	struct map *map;
1186 
1187 	map = map__new2(start, md->dso);
1188 	if (map == NULL)
1189 		return -ENOMEM;
1190 
1191 	map->end = map->start + len;
1192 	map->pgoff = pgoff;
1193 
1194 	list_add(&map->node, &md->maps);
1195 
1196 	return 0;
1197 }
1198 
1199 /*
1200  * Merges map into maps by splitting the new map within the existing map
1201  * regions.
1202  */
1203 int maps__merge_in(struct maps *kmaps, struct map *new_map)
1204 {
1205 	struct map *old_map;
1206 	LIST_HEAD(merged);
1207 
1208 	maps__for_each_entry(kmaps, old_map) {
1209 		/* no overload with this one */
1210 		if (new_map->end < old_map->start ||
1211 		    new_map->start >= old_map->end)
1212 			continue;
1213 
1214 		if (new_map->start < old_map->start) {
1215 			/*
1216 			 * |new......
1217 			 *       |old....
1218 			 */
1219 			if (new_map->end < old_map->end) {
1220 				/*
1221 				 * |new......|     -> |new..|
1222 				 *       |old....| ->       |old....|
1223 				 */
1224 				new_map->end = old_map->start;
1225 			} else {
1226 				/*
1227 				 * |new.............| -> |new..|       |new..|
1228 				 *       |old....|    ->       |old....|
1229 				 */
1230 				struct map *m = map__clone(new_map);
1231 
1232 				if (!m)
1233 					return -ENOMEM;
1234 
1235 				m->end = old_map->start;
1236 				list_add_tail(&m->node, &merged);
1237 				new_map->pgoff += old_map->end - new_map->start;
1238 				new_map->start = old_map->end;
1239 			}
1240 		} else {
1241 			/*
1242 			 *      |new......
1243 			 * |old....
1244 			 */
1245 			if (new_map->end < old_map->end) {
1246 				/*
1247 				 *      |new..|   -> x
1248 				 * |old.........| -> |old.........|
1249 				 */
1250 				map__put(new_map);
1251 				new_map = NULL;
1252 				break;
1253 			} else {
1254 				/*
1255 				 *      |new......| ->         |new...|
1256 				 * |old....|        -> |old....|
1257 				 */
1258 				new_map->pgoff += old_map->end - new_map->start;
1259 				new_map->start = old_map->end;
1260 			}
1261 		}
1262 	}
1263 
1264 	while (!list_empty(&merged)) {
1265 		old_map = list_entry(merged.next, struct map, node);
1266 		list_del_init(&old_map->node);
1267 		maps__insert(kmaps, old_map);
1268 		map__put(old_map);
1269 	}
1270 
1271 	if (new_map) {
1272 		maps__insert(kmaps, new_map);
1273 		map__put(new_map);
1274 	}
1275 	return 0;
1276 }
1277 
1278 static int dso__load_kcore(struct dso *dso, struct map *map,
1279 			   const char *kallsyms_filename)
1280 {
1281 	struct maps *kmaps = map__kmaps(map);
1282 	struct kcore_mapfn_data md;
1283 	struct map *old_map, *new_map, *replacement_map = NULL, *next;
1284 	struct machine *machine;
1285 	bool is_64_bit;
1286 	int err, fd;
1287 	char kcore_filename[PATH_MAX];
1288 	u64 stext;
1289 
1290 	if (!kmaps)
1291 		return -EINVAL;
1292 
1293 	machine = kmaps->machine;
1294 
1295 	/* This function requires that the map is the kernel map */
1296 	if (!__map__is_kernel(map))
1297 		return -EINVAL;
1298 
1299 	if (!filename_from_kallsyms_filename(kcore_filename, "kcore",
1300 					     kallsyms_filename))
1301 		return -EINVAL;
1302 
1303 	/* Modules and kernel must be present at their original addresses */
1304 	if (validate_kcore_addresses(kallsyms_filename, map))
1305 		return -EINVAL;
1306 
1307 	md.dso = dso;
1308 	INIT_LIST_HEAD(&md.maps);
1309 
1310 	fd = open(kcore_filename, O_RDONLY);
1311 	if (fd < 0) {
1312 		pr_debug("Failed to open %s. Note /proc/kcore requires CAP_SYS_RAWIO capability to access.\n",
1313 			 kcore_filename);
1314 		return -EINVAL;
1315 	}
1316 
1317 	/* Read new maps into temporary lists */
1318 	err = file__read_maps(fd, map->prot & PROT_EXEC, kcore_mapfn, &md,
1319 			      &is_64_bit);
1320 	if (err)
1321 		goto out_err;
1322 	dso->is_64_bit = is_64_bit;
1323 
1324 	if (list_empty(&md.maps)) {
1325 		err = -EINVAL;
1326 		goto out_err;
1327 	}
1328 
1329 	/* Remove old maps */
1330 	maps__for_each_entry_safe(kmaps, old_map, next) {
1331 		/*
1332 		 * We need to preserve eBPF maps even if they are
1333 		 * covered by kcore, because we need to access
1334 		 * eBPF dso for source data.
1335 		 */
1336 		if (old_map != map && !__map__is_bpf_prog(old_map))
1337 			maps__remove(kmaps, old_map);
1338 	}
1339 	machine->trampolines_mapped = false;
1340 
1341 	/* Find the kernel map using the '_stext' symbol */
1342 	if (!kallsyms__get_function_start(kallsyms_filename, "_stext", &stext)) {
1343 		list_for_each_entry(new_map, &md.maps, node) {
1344 			if (stext >= new_map->start && stext < new_map->end) {
1345 				replacement_map = new_map;
1346 				break;
1347 			}
1348 		}
1349 	}
1350 
1351 	if (!replacement_map)
1352 		replacement_map = list_entry(md.maps.next, struct map, node);
1353 
1354 	/* Add new maps */
1355 	while (!list_empty(&md.maps)) {
1356 		new_map = list_entry(md.maps.next, struct map, node);
1357 		list_del_init(&new_map->node);
1358 		if (new_map == replacement_map) {
1359 			map->start	= new_map->start;
1360 			map->end	= new_map->end;
1361 			map->pgoff	= new_map->pgoff;
1362 			map->map_ip	= new_map->map_ip;
1363 			map->unmap_ip	= new_map->unmap_ip;
1364 			/* Ensure maps are correctly ordered */
1365 			map__get(map);
1366 			maps__remove(kmaps, map);
1367 			maps__insert(kmaps, map);
1368 			map__put(map);
1369 			map__put(new_map);
1370 		} else {
1371 			/*
1372 			 * Merge kcore map into existing maps,
1373 			 * and ensure that current maps (eBPF)
1374 			 * stay intact.
1375 			 */
1376 			if (maps__merge_in(kmaps, new_map))
1377 				goto out_err;
1378 		}
1379 	}
1380 
1381 	if (machine__is(machine, "x86_64")) {
1382 		u64 addr;
1383 
1384 		/*
1385 		 * If one of the corresponding symbols is there, assume the
1386 		 * entry trampoline maps are too.
1387 		 */
1388 		if (!kallsyms__get_function_start(kallsyms_filename,
1389 						  ENTRY_TRAMPOLINE_NAME,
1390 						  &addr))
1391 			machine->trampolines_mapped = true;
1392 	}
1393 
1394 	/*
1395 	 * Set the data type and long name so that kcore can be read via
1396 	 * dso__data_read_addr().
1397 	 */
1398 	if (dso->kernel == DSO_SPACE__KERNEL_GUEST)
1399 		dso->binary_type = DSO_BINARY_TYPE__GUEST_KCORE;
1400 	else
1401 		dso->binary_type = DSO_BINARY_TYPE__KCORE;
1402 	dso__set_long_name(dso, strdup(kcore_filename), true);
1403 
1404 	close(fd);
1405 
1406 	if (map->prot & PROT_EXEC)
1407 		pr_debug("Using %s for kernel object code\n", kcore_filename);
1408 	else
1409 		pr_debug("Using %s for kernel data\n", kcore_filename);
1410 
1411 	return 0;
1412 
1413 out_err:
1414 	while (!list_empty(&md.maps)) {
1415 		map = list_entry(md.maps.next, struct map, node);
1416 		list_del_init(&map->node);
1417 		map__put(map);
1418 	}
1419 	close(fd);
1420 	return -EINVAL;
1421 }
1422 
1423 /*
1424  * If the kernel is relocated at boot time, kallsyms won't match.  Compute the
1425  * delta based on the relocation reference symbol.
1426  */
1427 static int kallsyms__delta(struct kmap *kmap, const char *filename, u64 *delta)
1428 {
1429 	u64 addr;
1430 
1431 	if (!kmap->ref_reloc_sym || !kmap->ref_reloc_sym->name)
1432 		return 0;
1433 
1434 	if (kallsyms__get_function_start(filename, kmap->ref_reloc_sym->name, &addr))
1435 		return -1;
1436 
1437 	*delta = addr - kmap->ref_reloc_sym->addr;
1438 	return 0;
1439 }
1440 
1441 int __dso__load_kallsyms(struct dso *dso, const char *filename,
1442 			 struct map *map, bool no_kcore)
1443 {
1444 	struct kmap *kmap = map__kmap(map);
1445 	u64 delta = 0;
1446 
1447 	if (symbol__restricted_filename(filename, "/proc/kallsyms"))
1448 		return -1;
1449 
1450 	if (!kmap || !kmap->kmaps)
1451 		return -1;
1452 
1453 	if (dso__load_all_kallsyms(dso, filename) < 0)
1454 		return -1;
1455 
1456 	if (kallsyms__delta(kmap, filename, &delta))
1457 		return -1;
1458 
1459 	symbols__fixup_end(&dso->symbols);
1460 	symbols__fixup_duplicate(&dso->symbols);
1461 
1462 	if (dso->kernel == DSO_SPACE__KERNEL_GUEST)
1463 		dso->symtab_type = DSO_BINARY_TYPE__GUEST_KALLSYMS;
1464 	else
1465 		dso->symtab_type = DSO_BINARY_TYPE__KALLSYMS;
1466 
1467 	if (!no_kcore && !dso__load_kcore(dso, map, filename))
1468 		return maps__split_kallsyms_for_kcore(kmap->kmaps, dso);
1469 	else
1470 		return maps__split_kallsyms(kmap->kmaps, dso, delta, map);
1471 }
1472 
1473 int dso__load_kallsyms(struct dso *dso, const char *filename,
1474 		       struct map *map)
1475 {
1476 	return __dso__load_kallsyms(dso, filename, map, false);
1477 }
1478 
1479 static int dso__load_perf_map(const char *map_path, struct dso *dso)
1480 {
1481 	char *line = NULL;
1482 	size_t n;
1483 	FILE *file;
1484 	int nr_syms = 0;
1485 
1486 	file = fopen(map_path, "r");
1487 	if (file == NULL)
1488 		goto out_failure;
1489 
1490 	while (!feof(file)) {
1491 		u64 start, size;
1492 		struct symbol *sym;
1493 		int line_len, len;
1494 
1495 		line_len = getline(&line, &n, file);
1496 		if (line_len < 0)
1497 			break;
1498 
1499 		if (!line)
1500 			goto out_failure;
1501 
1502 		line[--line_len] = '\0'; /* \n */
1503 
1504 		len = hex2u64(line, &start);
1505 
1506 		len++;
1507 		if (len + 2 >= line_len)
1508 			continue;
1509 
1510 		len += hex2u64(line + len, &size);
1511 
1512 		len++;
1513 		if (len + 2 >= line_len)
1514 			continue;
1515 
1516 		sym = symbol__new(start, size, STB_GLOBAL, STT_FUNC, line + len);
1517 
1518 		if (sym == NULL)
1519 			goto out_delete_line;
1520 
1521 		symbols__insert(&dso->symbols, sym);
1522 		nr_syms++;
1523 	}
1524 
1525 	free(line);
1526 	fclose(file);
1527 
1528 	return nr_syms;
1529 
1530 out_delete_line:
1531 	free(line);
1532 out_failure:
1533 	return -1;
1534 }
1535 
1536 #ifdef HAVE_LIBBFD_SUPPORT
1537 #define PACKAGE 'perf'
1538 #include <bfd.h>
1539 
1540 static int bfd_symbols__cmpvalue(const void *a, const void *b)
1541 {
1542 	const asymbol *as = *(const asymbol **)a, *bs = *(const asymbol **)b;
1543 
1544 	if (bfd_asymbol_value(as) != bfd_asymbol_value(bs))
1545 		return bfd_asymbol_value(as) - bfd_asymbol_value(bs);
1546 
1547 	return bfd_asymbol_name(as)[0] - bfd_asymbol_name(bs)[0];
1548 }
1549 
1550 static int bfd2elf_binding(asymbol *symbol)
1551 {
1552 	if (symbol->flags & BSF_WEAK)
1553 		return STB_WEAK;
1554 	if (symbol->flags & BSF_GLOBAL)
1555 		return STB_GLOBAL;
1556 	if (symbol->flags & BSF_LOCAL)
1557 		return STB_LOCAL;
1558 	return -1;
1559 }
1560 
1561 int dso__load_bfd_symbols(struct dso *dso, const char *debugfile)
1562 {
1563 	int err = -1;
1564 	long symbols_size, symbols_count;
1565 	asection *section;
1566 	asymbol **symbols, *sym;
1567 	struct symbol *symbol;
1568 	bfd *abfd;
1569 	u_int i;
1570 	u64 start, len;
1571 
1572 	abfd = bfd_openr(dso->long_name, NULL);
1573 	if (!abfd)
1574 		return -1;
1575 
1576 	if (!bfd_check_format(abfd, bfd_object)) {
1577 		pr_debug2("%s: cannot read %s bfd file.\n", __func__,
1578 			  dso->long_name);
1579 		goto out_close;
1580 	}
1581 
1582 	if (bfd_get_flavour(abfd) == bfd_target_elf_flavour)
1583 		goto out_close;
1584 
1585 	section = bfd_get_section_by_name(abfd, ".text");
1586 	if (section)
1587 		dso->text_offset = section->vma - section->filepos;
1588 
1589 	bfd_close(abfd);
1590 
1591 	abfd = bfd_openr(debugfile, NULL);
1592 	if (!abfd)
1593 		return -1;
1594 
1595 	if (!bfd_check_format(abfd, bfd_object)) {
1596 		pr_debug2("%s: cannot read %s bfd file.\n", __func__,
1597 			  debugfile);
1598 		goto out_close;
1599 	}
1600 
1601 	if (bfd_get_flavour(abfd) == bfd_target_elf_flavour)
1602 		goto out_close;
1603 
1604 	symbols_size = bfd_get_symtab_upper_bound(abfd);
1605 	if (symbols_size == 0) {
1606 		bfd_close(abfd);
1607 		return 0;
1608 	}
1609 
1610 	if (symbols_size < 0)
1611 		goto out_close;
1612 
1613 	symbols = malloc(symbols_size);
1614 	if (!symbols)
1615 		goto out_close;
1616 
1617 	symbols_count = bfd_canonicalize_symtab(abfd, symbols);
1618 	if (symbols_count < 0)
1619 		goto out_free;
1620 
1621 	qsort(symbols, symbols_count, sizeof(asymbol *), bfd_symbols__cmpvalue);
1622 
1623 #ifdef bfd_get_section
1624 #define bfd_asymbol_section bfd_get_section
1625 #endif
1626 	for (i = 0; i < symbols_count; ++i) {
1627 		sym = symbols[i];
1628 		section = bfd_asymbol_section(sym);
1629 		if (bfd2elf_binding(sym) < 0)
1630 			continue;
1631 
1632 		while (i + 1 < symbols_count &&
1633 		       bfd_asymbol_section(symbols[i + 1]) == section &&
1634 		       bfd2elf_binding(symbols[i + 1]) < 0)
1635 			i++;
1636 
1637 		if (i + 1 < symbols_count &&
1638 		    bfd_asymbol_section(symbols[i + 1]) == section)
1639 			len = symbols[i + 1]->value - sym->value;
1640 		else
1641 			len = section->size - sym->value;
1642 
1643 		start = bfd_asymbol_value(sym) - dso->text_offset;
1644 		symbol = symbol__new(start, len, bfd2elf_binding(sym), STT_FUNC,
1645 				     bfd_asymbol_name(sym));
1646 		if (!symbol)
1647 			goto out_free;
1648 
1649 		symbols__insert(&dso->symbols, symbol);
1650 	}
1651 #ifdef bfd_get_section
1652 #undef bfd_asymbol_section
1653 #endif
1654 
1655 	symbols__fixup_end(&dso->symbols);
1656 	symbols__fixup_duplicate(&dso->symbols);
1657 	dso->adjust_symbols = 1;
1658 
1659 	err = 0;
1660 out_free:
1661 	free(symbols);
1662 out_close:
1663 	bfd_close(abfd);
1664 	return err;
1665 }
1666 #endif
1667 
1668 static bool dso__is_compatible_symtab_type(struct dso *dso, bool kmod,
1669 					   enum dso_binary_type type)
1670 {
1671 	switch (type) {
1672 	case DSO_BINARY_TYPE__JAVA_JIT:
1673 	case DSO_BINARY_TYPE__DEBUGLINK:
1674 	case DSO_BINARY_TYPE__SYSTEM_PATH_DSO:
1675 	case DSO_BINARY_TYPE__FEDORA_DEBUGINFO:
1676 	case DSO_BINARY_TYPE__UBUNTU_DEBUGINFO:
1677 	case DSO_BINARY_TYPE__MIXEDUP_UBUNTU_DEBUGINFO:
1678 	case DSO_BINARY_TYPE__BUILDID_DEBUGINFO:
1679 	case DSO_BINARY_TYPE__OPENEMBEDDED_DEBUGINFO:
1680 		return !kmod && dso->kernel == DSO_SPACE__USER;
1681 
1682 	case DSO_BINARY_TYPE__KALLSYMS:
1683 	case DSO_BINARY_TYPE__VMLINUX:
1684 	case DSO_BINARY_TYPE__KCORE:
1685 		return dso->kernel == DSO_SPACE__KERNEL;
1686 
1687 	case DSO_BINARY_TYPE__GUEST_KALLSYMS:
1688 	case DSO_BINARY_TYPE__GUEST_VMLINUX:
1689 	case DSO_BINARY_TYPE__GUEST_KCORE:
1690 		return dso->kernel == DSO_SPACE__KERNEL_GUEST;
1691 
1692 	case DSO_BINARY_TYPE__GUEST_KMODULE:
1693 	case DSO_BINARY_TYPE__GUEST_KMODULE_COMP:
1694 	case DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE:
1695 	case DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP:
1696 		/*
1697 		 * kernel modules know their symtab type - it's set when
1698 		 * creating a module dso in machine__addnew_module_map().
1699 		 */
1700 		return kmod && dso->symtab_type == type;
1701 
1702 	case DSO_BINARY_TYPE__BUILD_ID_CACHE:
1703 	case DSO_BINARY_TYPE__BUILD_ID_CACHE_DEBUGINFO:
1704 		return true;
1705 
1706 	case DSO_BINARY_TYPE__BPF_PROG_INFO:
1707 	case DSO_BINARY_TYPE__BPF_IMAGE:
1708 	case DSO_BINARY_TYPE__OOL:
1709 	case DSO_BINARY_TYPE__NOT_FOUND:
1710 	default:
1711 		return false;
1712 	}
1713 }
1714 
1715 /* Checks for the existence of the perf-<pid>.map file in two different
1716  * locations.  First, if the process is a separate mount namespace, check in
1717  * that namespace using the pid of the innermost pid namespace.  If's not in a
1718  * namespace, or the file can't be found there, try in the mount namespace of
1719  * the tracing process using our view of its pid.
1720  */
1721 static int dso__find_perf_map(char *filebuf, size_t bufsz,
1722 			      struct nsinfo **nsip)
1723 {
1724 	struct nscookie nsc;
1725 	struct nsinfo *nsi;
1726 	struct nsinfo *nnsi;
1727 	int rc = -1;
1728 
1729 	nsi = *nsip;
1730 
1731 	if (nsi->need_setns) {
1732 		snprintf(filebuf, bufsz, "/tmp/perf-%d.map", nsi->nstgid);
1733 		nsinfo__mountns_enter(nsi, &nsc);
1734 		rc = access(filebuf, R_OK);
1735 		nsinfo__mountns_exit(&nsc);
1736 		if (rc == 0)
1737 			return rc;
1738 	}
1739 
1740 	nnsi = nsinfo__copy(nsi);
1741 	if (nnsi) {
1742 		nsinfo__put(nsi);
1743 
1744 		nnsi->need_setns = false;
1745 		snprintf(filebuf, bufsz, "/tmp/perf-%d.map", nnsi->tgid);
1746 		*nsip = nnsi;
1747 		rc = 0;
1748 	}
1749 
1750 	return rc;
1751 }
1752 
1753 int dso__load(struct dso *dso, struct map *map)
1754 {
1755 	char *name;
1756 	int ret = -1;
1757 	u_int i;
1758 	struct machine *machine = NULL;
1759 	char *root_dir = (char *) "";
1760 	int ss_pos = 0;
1761 	struct symsrc ss_[2];
1762 	struct symsrc *syms_ss = NULL, *runtime_ss = NULL;
1763 	bool kmod;
1764 	bool perfmap;
1765 	struct build_id bid;
1766 	struct nscookie nsc;
1767 	char newmapname[PATH_MAX];
1768 	const char *map_path = dso->long_name;
1769 
1770 	perfmap = strncmp(dso->name, "/tmp/perf-", 10) == 0;
1771 	if (perfmap) {
1772 		if (dso->nsinfo && (dso__find_perf_map(newmapname,
1773 		    sizeof(newmapname), &dso->nsinfo) == 0)) {
1774 			map_path = newmapname;
1775 		}
1776 	}
1777 
1778 	nsinfo__mountns_enter(dso->nsinfo, &nsc);
1779 	pthread_mutex_lock(&dso->lock);
1780 
1781 	/* check again under the dso->lock */
1782 	if (dso__loaded(dso)) {
1783 		ret = 1;
1784 		goto out;
1785 	}
1786 
1787 	kmod = dso->symtab_type == DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE ||
1788 		dso->symtab_type == DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP ||
1789 		dso->symtab_type == DSO_BINARY_TYPE__GUEST_KMODULE ||
1790 		dso->symtab_type == DSO_BINARY_TYPE__GUEST_KMODULE_COMP;
1791 
1792 	if (dso->kernel && !kmod) {
1793 		if (dso->kernel == DSO_SPACE__KERNEL)
1794 			ret = dso__load_kernel_sym(dso, map);
1795 		else if (dso->kernel == DSO_SPACE__KERNEL_GUEST)
1796 			ret = dso__load_guest_kernel_sym(dso, map);
1797 
1798 		machine = map__kmaps(map)->machine;
1799 		if (machine__is(machine, "x86_64"))
1800 			machine__map_x86_64_entry_trampolines(machine, dso);
1801 		goto out;
1802 	}
1803 
1804 	dso->adjust_symbols = 0;
1805 
1806 	if (perfmap) {
1807 		ret = dso__load_perf_map(map_path, dso);
1808 		dso->symtab_type = ret > 0 ? DSO_BINARY_TYPE__JAVA_JIT :
1809 					     DSO_BINARY_TYPE__NOT_FOUND;
1810 		goto out;
1811 	}
1812 
1813 	if (machine)
1814 		root_dir = machine->root_dir;
1815 
1816 	name = malloc(PATH_MAX);
1817 	if (!name)
1818 		goto out;
1819 
1820 	/*
1821 	 * Read the build id if possible. This is required for
1822 	 * DSO_BINARY_TYPE__BUILDID_DEBUGINFO to work
1823 	 */
1824 	if (!dso->has_build_id &&
1825 	    is_regular_file(dso->long_name)) {
1826 	    __symbol__join_symfs(name, PATH_MAX, dso->long_name);
1827 		if (filename__read_build_id(name, &bid) > 0)
1828 			dso__set_build_id(dso, &bid);
1829 	}
1830 
1831 	/*
1832 	 * Iterate over candidate debug images.
1833 	 * Keep track of "interesting" ones (those which have a symtab, dynsym,
1834 	 * and/or opd section) for processing.
1835 	 */
1836 	for (i = 0; i < DSO_BINARY_TYPE__SYMTAB_CNT; i++) {
1837 		struct symsrc *ss = &ss_[ss_pos];
1838 		bool next_slot = false;
1839 		bool is_reg;
1840 		bool nsexit;
1841 		int bfdrc = -1;
1842 		int sirc = -1;
1843 
1844 		enum dso_binary_type symtab_type = binary_type_symtab[i];
1845 
1846 		nsexit = (symtab_type == DSO_BINARY_TYPE__BUILD_ID_CACHE ||
1847 		    symtab_type == DSO_BINARY_TYPE__BUILD_ID_CACHE_DEBUGINFO);
1848 
1849 		if (!dso__is_compatible_symtab_type(dso, kmod, symtab_type))
1850 			continue;
1851 
1852 		if (dso__read_binary_type_filename(dso, symtab_type,
1853 						   root_dir, name, PATH_MAX))
1854 			continue;
1855 
1856 		if (nsexit)
1857 			nsinfo__mountns_exit(&nsc);
1858 
1859 		is_reg = is_regular_file(name);
1860 #ifdef HAVE_LIBBFD_SUPPORT
1861 		if (is_reg)
1862 			bfdrc = dso__load_bfd_symbols(dso, name);
1863 #endif
1864 		if (is_reg && bfdrc < 0)
1865 			sirc = symsrc__init(ss, dso, name, symtab_type);
1866 
1867 		if (nsexit)
1868 			nsinfo__mountns_enter(dso->nsinfo, &nsc);
1869 
1870 		if (bfdrc == 0)
1871 			break;
1872 
1873 		if (!is_reg || sirc < 0)
1874 			continue;
1875 
1876 		if (!syms_ss && symsrc__has_symtab(ss)) {
1877 			syms_ss = ss;
1878 			next_slot = true;
1879 			if (!dso->symsrc_filename)
1880 				dso->symsrc_filename = strdup(name);
1881 		}
1882 
1883 		if (!runtime_ss && symsrc__possibly_runtime(ss)) {
1884 			runtime_ss = ss;
1885 			next_slot = true;
1886 		}
1887 
1888 		if (next_slot) {
1889 			ss_pos++;
1890 
1891 			if (syms_ss && runtime_ss)
1892 				break;
1893 		} else {
1894 			symsrc__destroy(ss);
1895 		}
1896 
1897 	}
1898 
1899 	if (!runtime_ss && !syms_ss)
1900 		goto out_free;
1901 
1902 	if (runtime_ss && !syms_ss) {
1903 		syms_ss = runtime_ss;
1904 	}
1905 
1906 	/* We'll have to hope for the best */
1907 	if (!runtime_ss && syms_ss)
1908 		runtime_ss = syms_ss;
1909 
1910 	if (syms_ss)
1911 		ret = dso__load_sym(dso, map, syms_ss, runtime_ss, kmod);
1912 	else
1913 		ret = -1;
1914 
1915 	if (ret > 0) {
1916 		int nr_plt;
1917 
1918 		nr_plt = dso__synthesize_plt_symbols(dso, runtime_ss);
1919 		if (nr_plt > 0)
1920 			ret += nr_plt;
1921 	}
1922 
1923 	for (; ss_pos > 0; ss_pos--)
1924 		symsrc__destroy(&ss_[ss_pos - 1]);
1925 out_free:
1926 	free(name);
1927 	if (ret < 0 && strstr(dso->name, " (deleted)") != NULL)
1928 		ret = 0;
1929 out:
1930 	dso__set_loaded(dso);
1931 	pthread_mutex_unlock(&dso->lock);
1932 	nsinfo__mountns_exit(&nsc);
1933 
1934 	return ret;
1935 }
1936 
1937 static int map__strcmp(const void *a, const void *b)
1938 {
1939 	const struct map *ma = *(const struct map **)a, *mb = *(const struct map **)b;
1940 	return strcmp(ma->dso->short_name, mb->dso->short_name);
1941 }
1942 
1943 static int map__strcmp_name(const void *name, const void *b)
1944 {
1945 	const struct map *map = *(const struct map **)b;
1946 	return strcmp(name, map->dso->short_name);
1947 }
1948 
1949 void __maps__sort_by_name(struct maps *maps)
1950 {
1951 	qsort(maps->maps_by_name, maps->nr_maps, sizeof(struct map *), map__strcmp);
1952 }
1953 
1954 static int map__groups__sort_by_name_from_rbtree(struct maps *maps)
1955 {
1956 	struct map *map;
1957 	struct map **maps_by_name = realloc(maps->maps_by_name, maps->nr_maps * sizeof(map));
1958 	int i = 0;
1959 
1960 	if (maps_by_name == NULL)
1961 		return -1;
1962 
1963 	maps->maps_by_name = maps_by_name;
1964 	maps->nr_maps_allocated = maps->nr_maps;
1965 
1966 	maps__for_each_entry(maps, map)
1967 		maps_by_name[i++] = map;
1968 
1969 	__maps__sort_by_name(maps);
1970 	return 0;
1971 }
1972 
1973 static struct map *__maps__find_by_name(struct maps *maps, const char *name)
1974 {
1975 	struct map **mapp;
1976 
1977 	if (maps->maps_by_name == NULL &&
1978 	    map__groups__sort_by_name_from_rbtree(maps))
1979 		return NULL;
1980 
1981 	mapp = bsearch(name, maps->maps_by_name, maps->nr_maps, sizeof(*mapp), map__strcmp_name);
1982 	if (mapp)
1983 		return *mapp;
1984 	return NULL;
1985 }
1986 
1987 struct map *maps__find_by_name(struct maps *maps, const char *name)
1988 {
1989 	struct map *map;
1990 
1991 	down_read(&maps->lock);
1992 
1993 	if (maps->last_search_by_name && strcmp(maps->last_search_by_name->dso->short_name, name) == 0) {
1994 		map = maps->last_search_by_name;
1995 		goto out_unlock;
1996 	}
1997 	/*
1998 	 * If we have maps->maps_by_name, then the name isn't in the rbtree,
1999 	 * as maps->maps_by_name mirrors the rbtree when lookups by name are
2000 	 * made.
2001 	 */
2002 	map = __maps__find_by_name(maps, name);
2003 	if (map || maps->maps_by_name != NULL)
2004 		goto out_unlock;
2005 
2006 	/* Fallback to traversing the rbtree... */
2007 	maps__for_each_entry(maps, map)
2008 		if (strcmp(map->dso->short_name, name) == 0) {
2009 			maps->last_search_by_name = map;
2010 			goto out_unlock;
2011 		}
2012 
2013 	map = NULL;
2014 
2015 out_unlock:
2016 	up_read(&maps->lock);
2017 	return map;
2018 }
2019 
2020 int dso__load_vmlinux(struct dso *dso, struct map *map,
2021 		      const char *vmlinux, bool vmlinux_allocated)
2022 {
2023 	int err = -1;
2024 	struct symsrc ss;
2025 	char symfs_vmlinux[PATH_MAX];
2026 	enum dso_binary_type symtab_type;
2027 
2028 	if (vmlinux[0] == '/')
2029 		snprintf(symfs_vmlinux, sizeof(symfs_vmlinux), "%s", vmlinux);
2030 	else
2031 		symbol__join_symfs(symfs_vmlinux, vmlinux);
2032 
2033 	if (dso->kernel == DSO_SPACE__KERNEL_GUEST)
2034 		symtab_type = DSO_BINARY_TYPE__GUEST_VMLINUX;
2035 	else
2036 		symtab_type = DSO_BINARY_TYPE__VMLINUX;
2037 
2038 	if (symsrc__init(&ss, dso, symfs_vmlinux, symtab_type))
2039 		return -1;
2040 
2041 	err = dso__load_sym(dso, map, &ss, &ss, 0);
2042 	symsrc__destroy(&ss);
2043 
2044 	if (err > 0) {
2045 		if (dso->kernel == DSO_SPACE__KERNEL_GUEST)
2046 			dso->binary_type = DSO_BINARY_TYPE__GUEST_VMLINUX;
2047 		else
2048 			dso->binary_type = DSO_BINARY_TYPE__VMLINUX;
2049 		dso__set_long_name(dso, vmlinux, vmlinux_allocated);
2050 		dso__set_loaded(dso);
2051 		pr_debug("Using %s for symbols\n", symfs_vmlinux);
2052 	}
2053 
2054 	return err;
2055 }
2056 
2057 int dso__load_vmlinux_path(struct dso *dso, struct map *map)
2058 {
2059 	int i, err = 0;
2060 	char *filename = NULL;
2061 
2062 	pr_debug("Looking at the vmlinux_path (%d entries long)\n",
2063 		 vmlinux_path__nr_entries + 1);
2064 
2065 	for (i = 0; i < vmlinux_path__nr_entries; ++i) {
2066 		err = dso__load_vmlinux(dso, map, vmlinux_path[i], false);
2067 		if (err > 0)
2068 			goto out;
2069 	}
2070 
2071 	if (!symbol_conf.ignore_vmlinux_buildid)
2072 		filename = dso__build_id_filename(dso, NULL, 0, false);
2073 	if (filename != NULL) {
2074 		err = dso__load_vmlinux(dso, map, filename, true);
2075 		if (err > 0)
2076 			goto out;
2077 		free(filename);
2078 	}
2079 out:
2080 	return err;
2081 }
2082 
2083 static bool visible_dir_filter(const char *name, struct dirent *d)
2084 {
2085 	if (d->d_type != DT_DIR)
2086 		return false;
2087 	return lsdir_no_dot_filter(name, d);
2088 }
2089 
2090 static int find_matching_kcore(struct map *map, char *dir, size_t dir_sz)
2091 {
2092 	char kallsyms_filename[PATH_MAX];
2093 	int ret = -1;
2094 	struct strlist *dirs;
2095 	struct str_node *nd;
2096 
2097 	dirs = lsdir(dir, visible_dir_filter);
2098 	if (!dirs)
2099 		return -1;
2100 
2101 	strlist__for_each_entry(nd, dirs) {
2102 		scnprintf(kallsyms_filename, sizeof(kallsyms_filename),
2103 			  "%s/%s/kallsyms", dir, nd->s);
2104 		if (!validate_kcore_addresses(kallsyms_filename, map)) {
2105 			strlcpy(dir, kallsyms_filename, dir_sz);
2106 			ret = 0;
2107 			break;
2108 		}
2109 	}
2110 
2111 	strlist__delete(dirs);
2112 
2113 	return ret;
2114 }
2115 
2116 /*
2117  * Use open(O_RDONLY) to check readability directly instead of access(R_OK)
2118  * since access(R_OK) only checks with real UID/GID but open() use effective
2119  * UID/GID and actual capabilities (e.g. /proc/kcore requires CAP_SYS_RAWIO).
2120  */
2121 static bool filename__readable(const char *file)
2122 {
2123 	int fd = open(file, O_RDONLY);
2124 	if (fd < 0)
2125 		return false;
2126 	close(fd);
2127 	return true;
2128 }
2129 
2130 static char *dso__find_kallsyms(struct dso *dso, struct map *map)
2131 {
2132 	struct build_id bid;
2133 	char sbuild_id[SBUILD_ID_SIZE];
2134 	bool is_host = false;
2135 	char path[PATH_MAX];
2136 
2137 	if (!dso->has_build_id) {
2138 		/*
2139 		 * Last resort, if we don't have a build-id and couldn't find
2140 		 * any vmlinux file, try the running kernel kallsyms table.
2141 		 */
2142 		goto proc_kallsyms;
2143 	}
2144 
2145 	if (sysfs__read_build_id("/sys/kernel/notes", &bid) == 0)
2146 		is_host = dso__build_id_equal(dso, &bid);
2147 
2148 	/* Try a fast path for /proc/kallsyms if possible */
2149 	if (is_host) {
2150 		/*
2151 		 * Do not check the build-id cache, unless we know we cannot use
2152 		 * /proc/kcore or module maps don't match to /proc/kallsyms.
2153 		 * To check readability of /proc/kcore, do not use access(R_OK)
2154 		 * since /proc/kcore requires CAP_SYS_RAWIO to read and access
2155 		 * can't check it.
2156 		 */
2157 		if (filename__readable("/proc/kcore") &&
2158 		    !validate_kcore_addresses("/proc/kallsyms", map))
2159 			goto proc_kallsyms;
2160 	}
2161 
2162 	build_id__sprintf(&dso->bid, sbuild_id);
2163 
2164 	/* Find kallsyms in build-id cache with kcore */
2165 	scnprintf(path, sizeof(path), "%s/%s/%s",
2166 		  buildid_dir, DSO__NAME_KCORE, sbuild_id);
2167 
2168 	if (!find_matching_kcore(map, path, sizeof(path)))
2169 		return strdup(path);
2170 
2171 	/* Use current /proc/kallsyms if possible */
2172 	if (is_host) {
2173 proc_kallsyms:
2174 		return strdup("/proc/kallsyms");
2175 	}
2176 
2177 	/* Finally, find a cache of kallsyms */
2178 	if (!build_id_cache__kallsyms_path(sbuild_id, path, sizeof(path))) {
2179 		pr_err("No kallsyms or vmlinux with build-id %s was found\n",
2180 		       sbuild_id);
2181 		return NULL;
2182 	}
2183 
2184 	return strdup(path);
2185 }
2186 
2187 static int dso__load_kernel_sym(struct dso *dso, struct map *map)
2188 {
2189 	int err;
2190 	const char *kallsyms_filename = NULL;
2191 	char *kallsyms_allocated_filename = NULL;
2192 	char *filename = NULL;
2193 
2194 	/*
2195 	 * Step 1: if the user specified a kallsyms or vmlinux filename, use
2196 	 * it and only it, reporting errors to the user if it cannot be used.
2197 	 *
2198 	 * For instance, try to analyse an ARM perf.data file _without_ a
2199 	 * build-id, or if the user specifies the wrong path to the right
2200 	 * vmlinux file, obviously we can't fallback to another vmlinux (a
2201 	 * x86_86 one, on the machine where analysis is being performed, say),
2202 	 * or worse, /proc/kallsyms.
2203 	 *
2204 	 * If the specified file _has_ a build-id and there is a build-id
2205 	 * section in the perf.data file, we will still do the expected
2206 	 * validation in dso__load_vmlinux and will bail out if they don't
2207 	 * match.
2208 	 */
2209 	if (symbol_conf.kallsyms_name != NULL) {
2210 		kallsyms_filename = symbol_conf.kallsyms_name;
2211 		goto do_kallsyms;
2212 	}
2213 
2214 	if (!symbol_conf.ignore_vmlinux && symbol_conf.vmlinux_name != NULL) {
2215 		return dso__load_vmlinux(dso, map, symbol_conf.vmlinux_name, false);
2216 	}
2217 
2218 	/*
2219 	 * Before checking on common vmlinux locations, check if it's
2220 	 * stored as standard build id binary (not kallsyms) under
2221 	 * .debug cache.
2222 	 */
2223 	if (!symbol_conf.ignore_vmlinux_buildid)
2224 		filename = __dso__build_id_filename(dso, NULL, 0, false, false);
2225 	if (filename != NULL) {
2226 		err = dso__load_vmlinux(dso, map, filename, true);
2227 		if (err > 0)
2228 			return err;
2229 		free(filename);
2230 	}
2231 
2232 	if (!symbol_conf.ignore_vmlinux && vmlinux_path != NULL) {
2233 		err = dso__load_vmlinux_path(dso, map);
2234 		if (err > 0)
2235 			return err;
2236 	}
2237 
2238 	/* do not try local files if a symfs was given */
2239 	if (symbol_conf.symfs[0] != 0)
2240 		return -1;
2241 
2242 	kallsyms_allocated_filename = dso__find_kallsyms(dso, map);
2243 	if (!kallsyms_allocated_filename)
2244 		return -1;
2245 
2246 	kallsyms_filename = kallsyms_allocated_filename;
2247 
2248 do_kallsyms:
2249 	err = dso__load_kallsyms(dso, kallsyms_filename, map);
2250 	if (err > 0)
2251 		pr_debug("Using %s for symbols\n", kallsyms_filename);
2252 	free(kallsyms_allocated_filename);
2253 
2254 	if (err > 0 && !dso__is_kcore(dso)) {
2255 		dso->binary_type = DSO_BINARY_TYPE__KALLSYMS;
2256 		dso__set_long_name(dso, DSO__NAME_KALLSYMS, false);
2257 		map__fixup_start(map);
2258 		map__fixup_end(map);
2259 	}
2260 
2261 	return err;
2262 }
2263 
2264 static int dso__load_guest_kernel_sym(struct dso *dso, struct map *map)
2265 {
2266 	int err;
2267 	const char *kallsyms_filename = NULL;
2268 	struct machine *machine = map__kmaps(map)->machine;
2269 	char path[PATH_MAX];
2270 
2271 	if (machine__is_default_guest(machine)) {
2272 		/*
2273 		 * if the user specified a vmlinux filename, use it and only
2274 		 * it, reporting errors to the user if it cannot be used.
2275 		 * Or use file guest_kallsyms inputted by user on commandline
2276 		 */
2277 		if (symbol_conf.default_guest_vmlinux_name != NULL) {
2278 			err = dso__load_vmlinux(dso, map,
2279 						symbol_conf.default_guest_vmlinux_name,
2280 						false);
2281 			return err;
2282 		}
2283 
2284 		kallsyms_filename = symbol_conf.default_guest_kallsyms;
2285 		if (!kallsyms_filename)
2286 			return -1;
2287 	} else {
2288 		sprintf(path, "%s/proc/kallsyms", machine->root_dir);
2289 		kallsyms_filename = path;
2290 	}
2291 
2292 	err = dso__load_kallsyms(dso, kallsyms_filename, map);
2293 	if (err > 0)
2294 		pr_debug("Using %s for symbols\n", kallsyms_filename);
2295 	if (err > 0 && !dso__is_kcore(dso)) {
2296 		dso->binary_type = DSO_BINARY_TYPE__GUEST_KALLSYMS;
2297 		dso__set_long_name(dso, machine->mmap_name, false);
2298 		map__fixup_start(map);
2299 		map__fixup_end(map);
2300 	}
2301 
2302 	return err;
2303 }
2304 
2305 static void vmlinux_path__exit(void)
2306 {
2307 	while (--vmlinux_path__nr_entries >= 0)
2308 		zfree(&vmlinux_path[vmlinux_path__nr_entries]);
2309 	vmlinux_path__nr_entries = 0;
2310 
2311 	zfree(&vmlinux_path);
2312 }
2313 
2314 static const char * const vmlinux_paths[] = {
2315 	"vmlinux",
2316 	"/boot/vmlinux"
2317 };
2318 
2319 static const char * const vmlinux_paths_upd[] = {
2320 	"/boot/vmlinux-%s",
2321 	"/usr/lib/debug/boot/vmlinux-%s",
2322 	"/lib/modules/%s/build/vmlinux",
2323 	"/usr/lib/debug/lib/modules/%s/vmlinux",
2324 	"/usr/lib/debug/boot/vmlinux-%s.debug"
2325 };
2326 
2327 static int vmlinux_path__add(const char *new_entry)
2328 {
2329 	vmlinux_path[vmlinux_path__nr_entries] = strdup(new_entry);
2330 	if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
2331 		return -1;
2332 	++vmlinux_path__nr_entries;
2333 
2334 	return 0;
2335 }
2336 
2337 static int vmlinux_path__init(struct perf_env *env)
2338 {
2339 	struct utsname uts;
2340 	char bf[PATH_MAX];
2341 	char *kernel_version;
2342 	unsigned int i;
2343 
2344 	vmlinux_path = malloc(sizeof(char *) * (ARRAY_SIZE(vmlinux_paths) +
2345 			      ARRAY_SIZE(vmlinux_paths_upd)));
2346 	if (vmlinux_path == NULL)
2347 		return -1;
2348 
2349 	for (i = 0; i < ARRAY_SIZE(vmlinux_paths); i++)
2350 		if (vmlinux_path__add(vmlinux_paths[i]) < 0)
2351 			goto out_fail;
2352 
2353 	/* only try kernel version if no symfs was given */
2354 	if (symbol_conf.symfs[0] != 0)
2355 		return 0;
2356 
2357 	if (env) {
2358 		kernel_version = env->os_release;
2359 	} else {
2360 		if (uname(&uts) < 0)
2361 			goto out_fail;
2362 
2363 		kernel_version = uts.release;
2364 	}
2365 
2366 	for (i = 0; i < ARRAY_SIZE(vmlinux_paths_upd); i++) {
2367 		snprintf(bf, sizeof(bf), vmlinux_paths_upd[i], kernel_version);
2368 		if (vmlinux_path__add(bf) < 0)
2369 			goto out_fail;
2370 	}
2371 
2372 	return 0;
2373 
2374 out_fail:
2375 	vmlinux_path__exit();
2376 	return -1;
2377 }
2378 
2379 int setup_list(struct strlist **list, const char *list_str,
2380 		      const char *list_name)
2381 {
2382 	if (list_str == NULL)
2383 		return 0;
2384 
2385 	*list = strlist__new(list_str, NULL);
2386 	if (!*list) {
2387 		pr_err("problems parsing %s list\n", list_name);
2388 		return -1;
2389 	}
2390 
2391 	symbol_conf.has_filter = true;
2392 	return 0;
2393 }
2394 
2395 int setup_intlist(struct intlist **list, const char *list_str,
2396 		  const char *list_name)
2397 {
2398 	if (list_str == NULL)
2399 		return 0;
2400 
2401 	*list = intlist__new(list_str);
2402 	if (!*list) {
2403 		pr_err("problems parsing %s list\n", list_name);
2404 		return -1;
2405 	}
2406 	return 0;
2407 }
2408 
2409 static bool symbol__read_kptr_restrict(void)
2410 {
2411 	bool value = false;
2412 	FILE *fp = fopen("/proc/sys/kernel/kptr_restrict", "r");
2413 
2414 	if (fp != NULL) {
2415 		char line[8];
2416 
2417 		if (fgets(line, sizeof(line), fp) != NULL)
2418 			value = perf_cap__capable(CAP_SYSLOG) ?
2419 					(atoi(line) >= 2) :
2420 					(atoi(line) != 0);
2421 
2422 		fclose(fp);
2423 	}
2424 
2425 	/* Per kernel/kallsyms.c:
2426 	 * we also restrict when perf_event_paranoid > 1 w/o CAP_SYSLOG
2427 	 */
2428 	if (perf_event_paranoid() > 1 && !perf_cap__capable(CAP_SYSLOG))
2429 		value = true;
2430 
2431 	return value;
2432 }
2433 
2434 int symbol__annotation_init(void)
2435 {
2436 	if (symbol_conf.init_annotation)
2437 		return 0;
2438 
2439 	if (symbol_conf.initialized) {
2440 		pr_err("Annotation needs to be init before symbol__init()\n");
2441 		return -1;
2442 	}
2443 
2444 	symbol_conf.priv_size += sizeof(struct annotation);
2445 	symbol_conf.init_annotation = true;
2446 	return 0;
2447 }
2448 
2449 int symbol__init(struct perf_env *env)
2450 {
2451 	const char *symfs;
2452 
2453 	if (symbol_conf.initialized)
2454 		return 0;
2455 
2456 	symbol_conf.priv_size = PERF_ALIGN(symbol_conf.priv_size, sizeof(u64));
2457 
2458 	symbol__elf_init();
2459 
2460 	if (symbol_conf.sort_by_name)
2461 		symbol_conf.priv_size += (sizeof(struct symbol_name_rb_node) -
2462 					  sizeof(struct symbol));
2463 
2464 	if (symbol_conf.try_vmlinux_path && vmlinux_path__init(env) < 0)
2465 		return -1;
2466 
2467 	if (symbol_conf.field_sep && *symbol_conf.field_sep == '.') {
2468 		pr_err("'.' is the only non valid --field-separator argument\n");
2469 		return -1;
2470 	}
2471 
2472 	if (setup_list(&symbol_conf.dso_list,
2473 		       symbol_conf.dso_list_str, "dso") < 0)
2474 		return -1;
2475 
2476 	if (setup_list(&symbol_conf.comm_list,
2477 		       symbol_conf.comm_list_str, "comm") < 0)
2478 		goto out_free_dso_list;
2479 
2480 	if (setup_intlist(&symbol_conf.pid_list,
2481 		       symbol_conf.pid_list_str, "pid") < 0)
2482 		goto out_free_comm_list;
2483 
2484 	if (setup_intlist(&symbol_conf.tid_list,
2485 		       symbol_conf.tid_list_str, "tid") < 0)
2486 		goto out_free_pid_list;
2487 
2488 	if (setup_list(&symbol_conf.sym_list,
2489 		       symbol_conf.sym_list_str, "symbol") < 0)
2490 		goto out_free_tid_list;
2491 
2492 	if (setup_list(&symbol_conf.bt_stop_list,
2493 		       symbol_conf.bt_stop_list_str, "symbol") < 0)
2494 		goto out_free_sym_list;
2495 
2496 	/*
2497 	 * A path to symbols of "/" is identical to ""
2498 	 * reset here for simplicity.
2499 	 */
2500 	symfs = realpath(symbol_conf.symfs, NULL);
2501 	if (symfs == NULL)
2502 		symfs = symbol_conf.symfs;
2503 	if (strcmp(symfs, "/") == 0)
2504 		symbol_conf.symfs = "";
2505 	if (symfs != symbol_conf.symfs)
2506 		free((void *)symfs);
2507 
2508 	symbol_conf.kptr_restrict = symbol__read_kptr_restrict();
2509 
2510 	symbol_conf.initialized = true;
2511 	return 0;
2512 
2513 out_free_sym_list:
2514 	strlist__delete(symbol_conf.sym_list);
2515 out_free_tid_list:
2516 	intlist__delete(symbol_conf.tid_list);
2517 out_free_pid_list:
2518 	intlist__delete(symbol_conf.pid_list);
2519 out_free_comm_list:
2520 	strlist__delete(symbol_conf.comm_list);
2521 out_free_dso_list:
2522 	strlist__delete(symbol_conf.dso_list);
2523 	return -1;
2524 }
2525 
2526 void symbol__exit(void)
2527 {
2528 	if (!symbol_conf.initialized)
2529 		return;
2530 	strlist__delete(symbol_conf.bt_stop_list);
2531 	strlist__delete(symbol_conf.sym_list);
2532 	strlist__delete(symbol_conf.dso_list);
2533 	strlist__delete(symbol_conf.comm_list);
2534 	intlist__delete(symbol_conf.tid_list);
2535 	intlist__delete(symbol_conf.pid_list);
2536 	vmlinux_path__exit();
2537 	symbol_conf.sym_list = symbol_conf.dso_list = symbol_conf.comm_list = NULL;
2538 	symbol_conf.bt_stop_list = NULL;
2539 	symbol_conf.initialized = false;
2540 }
2541 
2542 int symbol__config_symfs(const struct option *opt __maybe_unused,
2543 			 const char *dir, int unset __maybe_unused)
2544 {
2545 	char *bf = NULL;
2546 	int ret;
2547 
2548 	symbol_conf.symfs = strdup(dir);
2549 	if (symbol_conf.symfs == NULL)
2550 		return -ENOMEM;
2551 
2552 	/* skip the locally configured cache if a symfs is given, and
2553 	 * config buildid dir to symfs/.debug
2554 	 */
2555 	ret = asprintf(&bf, "%s/%s", dir, ".debug");
2556 	if (ret < 0)
2557 		return -ENOMEM;
2558 
2559 	set_buildid_dir(bf);
2560 
2561 	free(bf);
2562 	return 0;
2563 }
2564 
2565 struct mem_info *mem_info__get(struct mem_info *mi)
2566 {
2567 	if (mi)
2568 		refcount_inc(&mi->refcnt);
2569 	return mi;
2570 }
2571 
2572 void mem_info__put(struct mem_info *mi)
2573 {
2574 	if (mi && refcount_dec_and_test(&mi->refcnt))
2575 		free(mi);
2576 }
2577 
2578 struct mem_info *mem_info__new(void)
2579 {
2580 	struct mem_info *mi = zalloc(sizeof(*mi));
2581 
2582 	if (mi)
2583 		refcount_set(&mi->refcnt, 1);
2584 	return mi;
2585 }
2586