xref: /openbmc/linux/tools/perf/util/symbol.c (revision 83f865d7)
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);
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 }
2563