text: // SPDX-License-Identifier: GPL-2.0
  #include <dirent.h>
  #include <errno.h>
  #include <stdlib.h>
  #include <stdio.h>
  #include <string.h>
  #include <linux/kernel.h>
  #include <linux/mman.h>
  #include <sys/types.h>
  #include <sys/stat.h>
  #include <sys/param.h>
  #include <fcntl.h>
  #include <unistd.h>
  #include <inttypes.h>
  #include "annotate.h"
  #include "build-id.h"
  #include "util.h"
  #include "debug.h"
  #include "machine.h"
  #include "symbol.h"
  #include "strlist.h"
  #include "intlist.h"
  #include "namespaces.h"
  #include "header.h"
  #include "path.h"
  #include "sane_ctype.h"
  
  #include <elf.h>
  #include <limits.h>
  #include <symbol/kallsyms.h>
  #include <sys/utsname.h>
  
  static int dso__load_kernel_sym(struct dso *dso, struct map *map);
  static int dso__load_guest_kernel_sym(struct dso *dso, struct map *map);
  static bool symbol__is_idle(const char *name);
  
  int vmlinux_path__nr_entries;
  char **vmlinux_path;
  
  struct symbol_conf symbol_conf = {
  	.use_modules		= true,
  	.try_vmlinux_path	= true,
  	.demangle		= true,
  	.demangle_kernel	= false,
  	.cumulate_callchain	= true,
  	.show_hist_headers	= true,
  	.symfs			= "",
  	.event_group		= true,
  	.inline_name		= true,
  };
  
  static enum dso_binary_type binary_type_symtab[] = {
  	DSO_BINARY_TYPE__KALLSYMS,
  	DSO_BINARY_TYPE__GUEST_KALLSYMS,
  	DSO_BINARY_TYPE__JAVA_JIT,
  	DSO_BINARY_TYPE__DEBUGLINK,
  	DSO_BINARY_TYPE__BUILD_ID_CACHE,
  	DSO_BINARY_TYPE__BUILD_ID_CACHE_DEBUGINFO,
  	DSO_BINARY_TYPE__FEDORA_DEBUGINFO,
  	DSO_BINARY_TYPE__UBUNTU_DEBUGINFO,
  	DSO_BINARY_TYPE__BUILDID_DEBUGINFO,
  	DSO_BINARY_TYPE__SYSTEM_PATH_DSO,
  	DSO_BINARY_TYPE__GUEST_KMODULE,
  	DSO_BINARY_TYPE__GUEST_KMODULE_COMP,
  	DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE,
  	DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP,
  	DSO_BINARY_TYPE__OPENEMBEDDED_DEBUGINFO,
  	DSO_BINARY_TYPE__NOT_FOUND,
  };
  
  #define DSO_BINARY_TYPE__SYMTAB_CNT ARRAY_SIZE(binary_type_symtab)
  
  static bool symbol_type__filter(char symbol_type)
  {
  	symbol_type = toupper(symbol_type);
  	return symbol_type == 'T' || symbol_type == 'W' || symbol_type == 'D' || symbol_type == 'B';
  }
  
  static int prefix_underscores_count(const char *str)
  {
  	const char *tail = str;
  
  	while (*tail == '_')
  		tail++;
  
  	return tail - str;
  }
  
  const char * __weak arch__normalize_symbol_name(const char *name)
  {
  	return name;
  }
  
  int __weak arch__compare_symbol_names(const char *namea, const char *nameb)
  {
  	return strcmp(namea, nameb);
  }
  
  int __weak arch__compare_symbol_names_n(const char *namea, const char *nameb,
  					unsigned int n)
  {
  	return strncmp(namea, nameb, n);
  }
  
  int __weak arch__choose_best_symbol(struct symbol *syma,
  				    struct symbol *symb __maybe_unused)
  {
  	/* Avoid "SyS" kernel syscall aliases */
  	if (strlen(syma->name) >= 3 && !strncmp(syma->name, "SyS", 3))
  		return SYMBOL_B;
  	if (strlen(syma->name) >= 10 && !strncmp(syma->name, "compat_SyS", 10))
  		return SYMBOL_B;
  
  	return SYMBOL_A;
  }
  
  static int choose_best_symbol(struct symbol *syma, struct symbol *symb)
  {
  	s64 a;
  	s64 b;
  	size_t na, nb;
  
  	/* Prefer a symbol with non zero length */
  	a = syma->end - syma->start;
  	b = symb->end - symb->start;
  	if ((b == 0) && (a > 0))
  		return SYMBOL_A;
  	else if ((a == 0) && (b > 0))
  		return SYMBOL_B;
  
  	/* Prefer a non weak symbol over a weak one */
  	a = syma->binding == STB_WEAK;
  	b = symb->binding == STB_WEAK;
  	if (b && !a)
  		return SYMBOL_A;
  	if (a && !b)
  		return SYMBOL_B;
  
  	/* Prefer a global symbol over a non global one */
  	a = syma->binding == STB_GLOBAL;
  	b = symb->binding == STB_GLOBAL;
  	if (a && !b)
  		return SYMBOL_A;
  	if (b && !a)
  		return SYMBOL_B;
  
  	/* Prefer a symbol with less underscores */
  	a = prefix_underscores_count(syma->name);
  	b = prefix_underscores_count(symb->name);
  	if (b > a)
  		return SYMBOL_A;
  	else if (a > b)
  		return SYMBOL_B;
  
  	/* Choose the symbol with the longest name */
  	na = strlen(syma->name);
  	nb = strlen(symb->name);
  	if (na > nb)
  		return SYMBOL_A;
  	else if (na < nb)
  		return SYMBOL_B;
  
  	return arch__choose_best_symbol(syma, symb);
  }
  
  void symbols__fixup_duplicate(struct rb_root *symbols)
  {
  	struct rb_node *nd;
  	struct symbol *curr, *next;
  
  	if (symbol_conf.allow_aliases)
  		return;
  
  	nd = rb_first(symbols);
  
  	while (nd) {
  		curr = rb_entry(nd, struct symbol, rb_node);
  again:
  		nd = rb_next(&curr->rb_node);
  		next = rb_entry(nd, struct symbol, rb_node);
  
  		if (!nd)
  			break;
  
  		if (curr->start != next->start)
  			continue;
  
  		if (choose_best_symbol(curr, next) == SYMBOL_A) {
  			rb_erase(&next->rb_node, symbols);
  			symbol__delete(next);
  			goto again;
  		} else {
  			nd = rb_next(&curr->rb_node);
  			rb_erase(&curr->rb_node, symbols);
  			symbol__delete(curr);
  		}
  	}
  }
  
  void symbols__fixup_end(struct rb_root *symbols)
  {
  	struct rb_node *nd, *prevnd = rb_first(symbols);
  	struct symbol *curr, *prev;
  
  	if (prevnd == NULL)
  		return;
  
  	curr = rb_entry(prevnd, struct symbol, rb_node);
  
  	for (nd = rb_next(prevnd); nd; nd = rb_next(nd)) {
  		prev = curr;
  		curr = rb_entry(nd, struct symbol, rb_node);
  
  		if (prev->end == prev->start && prev->end != curr->start)
  			prev->end = curr->start;
  	}
  
  	/* Last entry */
  	if (curr->end == curr->start)
  		curr->end = roundup(curr->start, 4096) + 4096;
  }
  
  void map_groups__fixup_end(struct map_groups *mg)
  {
  	struct maps *maps = &mg->maps;
  	struct map *next, *curr;
  
  	down_write(&maps->lock);
  
  	curr = maps__first(maps);
  	if (curr == NULL)
  		goto out_unlock;
  
  	for (next = map__next(curr); next; next = map__next(curr)) {
  		if (!curr->end)
  			curr->end = next->start;
  		curr = next;
  	}
  
  	/*
  	 * We still haven't the actual symbols, so guess the
  	 * last map final address.
  	 */
  	if (!curr->end)
  		curr->end = ~0ULL;
  
  out_unlock:
  	up_write(&maps->lock);
  }
  
  struct symbol *symbol__new(u64 start, u64 len, u8 binding, u8 type, const char *name)
  {
  	size_t namelen = strlen(name) + 1;
  	struct symbol *sym = calloc(1, (symbol_conf.priv_size +
  					sizeof(*sym) + namelen));
  	if (sym == NULL)
  		return NULL;
  
  	if (symbol_conf.priv_size) {
  		if (symbol_conf.init_annotation) {
  			struct annotation *notes = (void *)sym;
  			pthread_mutex_init(&notes->lock, NULL);
  		}
  		sym = ((void *)sym) + symbol_conf.priv_size;
  	}
  
  	sym->start   = start;
  	sym->end     = len ? start + len : start;
  	sym->type    = type;
  	sym->binding = binding;
  	sym->namelen = namelen - 1;
  
  	pr_debug4("%s: %s %#" PRIx64 "-%#" PRIx64 "\n",
  		  __func__, name, start, sym->end);
  	memcpy(sym->name, name, namelen);
  
  	return sym;
  }
  
  void symbol__delete(struct symbol *sym)
  {
  	free(((void *)sym) - symbol_conf.priv_size);
  }
  
  void symbols__delete(struct rb_root *symbols)
  {
  	struct symbol *pos;
  	struct rb_node *next = rb_first(symbols);
  
  	while (next) {
  		pos = rb_entry(next, struct symbol, rb_node);
  		next = rb_next(&pos->rb_node);
  		rb_erase(&pos->rb_node, symbols);
  		symbol__delete(pos);
  	}
  }
  
  void __symbols__insert(struct rb_root *symbols, struct symbol *sym, bool kernel)
  {
  	struct rb_node **p = &symbols->rb_node;
  	struct rb_node *parent = NULL;
  	const u64 ip = sym->start;
  	struct symbol *s;
  
  	if (kernel) {
  		const char *name = sym->name;
  		/*
  		 * ppc64 uses function descriptors and appends a '.' to the
  		 * start of every instruction address. Remove it.
  		 */
  		if (name[0] == '.')
  			name++;
  		sym->idle = symbol__is_idle(name);
  	}
  
  	while (*p != NULL) {
  		parent = *p;
  		s = rb_entry(parent, struct symbol, rb_node);
  		if (ip < s->start)
  			p = &(*p)->rb_left;
  		else
  			p = &(*p)->rb_right;
  	}
  	rb_link_node(&sym->rb_node, parent, p);
  	rb_insert_color(&sym->rb_node, symbols);
  }
  
  void symbols__insert(struct rb_root *symbols, struct symbol *sym)
  {
  	__symbols__insert(symbols, sym, false);
  }
  
  static struct symbol *symbols__find(struct rb_root *symbols, u64 ip)
  {
  	struct rb_node *n;
  
  	if (symbols == NULL)
  		return NULL;
  
  	n = symbols->rb_node;
  
  	while (n) {
  		struct symbol *s = rb_entry(n, struct symbol, rb_node);
  
  		if (ip < s->start)
  			n = n->rb_left;
  		else if (ip > s->end || (ip == s->end && ip != s->start))
  			n = n->rb_right;
  		else
  			return s;
  	}
  
  	return NULL;
  }
  
  static struct symbol *symbols__first(struct rb_root *symbols)
  {
  	struct rb_node *n = rb_first(symbols);
  
  	if (n)
  		return rb_entry(n, struct symbol, rb_node);
  
  	return NULL;
  }
  
  static struct symbol *symbols__last(struct rb_root *symbols)
  {
  	struct rb_node *n = rb_last(symbols);
  
  	if (n)
  		return rb_entry(n, struct symbol, rb_node);
  
  	return NULL;
  }
  
  static struct symbol *symbols__next(struct symbol *sym)
  {
  	struct rb_node *n = rb_next(&sym->rb_node);
  
  	if (n)
  		return rb_entry(n, struct symbol, rb_node);
  
  	return NULL;
  }
  
  static void symbols__insert_by_name(struct rb_root *symbols, struct symbol *sym)
  {
  	struct rb_node **p = &symbols->rb_node;
  	struct rb_node *parent = NULL;
  	struct symbol_name_rb_node *symn, *s;
  
  	symn = container_of(sym, struct symbol_name_rb_node, sym);
  
  	while (*p != NULL) {
  		parent = *p;
  		s = rb_entry(parent, struct symbol_name_rb_node, rb_node);
  		if (strcmp(sym->name, s->sym.name) < 0)
  			p = &(*p)->rb_left;
  		else
  			p = &(*p)->rb_right;
  	}
  	rb_link_node(&symn->rb_node, parent, p);
  	rb_insert_color(&symn->rb_node, symbols);
  }
  
  static void symbols__sort_by_name(struct rb_root *symbols,
  				  struct rb_root *source)
  {
  	struct rb_node *nd;
  
  	for (nd = rb_first(source); nd; nd = rb_next(nd)) {
  		struct symbol *pos = rb_entry(nd, struct symbol, rb_node);
  		symbols__insert_by_name(symbols, pos);
  	}
  }
  
  int symbol__match_symbol_name(const char *name, const char *str,
  			      enum symbol_tag_include includes)
  {
  	const char *versioning;
  
  	if (includes == SYMBOL_TAG_INCLUDE__DEFAULT_ONLY &&
  	    (versioning = strstr(name, "@@"))) {
  		int len = strlen(str);
  
  		if (len < versioning - name)
  			len = versioning - name;
  
  		return arch__compare_symbol_names_n(name, str, len);
  	} else
  		return arch__compare_symbol_names(name, str);
  }
  
  static struct symbol *symbols__find_by_name(struct rb_root *symbols,
  					    const char *name,
  					    enum symbol_tag_include includes)
  {
  	struct rb_node *n;
  	struct symbol_name_rb_node *s = NULL;
  
  	if (symbols == NULL)
  		return NULL;
  
  	n = symbols->rb_node;
  
  	while (n) {
  		int cmp;
  
  		s = rb_entry(n, struct symbol_name_rb_node, rb_node);
  		cmp = symbol__match_symbol_name(s->sym.name, name, includes);
  
  		if (cmp > 0)
  			n = n->rb_left;
  		else if (cmp < 0)
  			n = n->rb_right;
  		else
  			break;
  	}
  
  	if (n == NULL)
  		return NULL;
  
  	if (includes != SYMBOL_TAG_INCLUDE__DEFAULT_ONLY)
  		/* return first symbol that has same name (if any) */
  		for (n = rb_prev(n); n; n = rb_prev(n)) {
  			struct symbol_name_rb_node *tmp;
  
  			tmp = rb_entry(n, struct symbol_name_rb_node, rb_node);
  			if (arch__compare_symbol_names(tmp->sym.name, s->sym.name))
  				break;
  
  			s = tmp;
  		}
  
  	return &s->sym;
  }
  
  void dso__reset_find_symbol_cache(struct dso *dso)
  {
  	dso->last_find_result.addr   = 0;
  	dso->last_find_result.symbol = NULL;
  }
  
  void dso__insert_symbol(struct dso *dso, struct symbol *sym)
  {
  	__symbols__insert(&dso->symbols, sym, dso->kernel);
  
  	/* update the symbol cache if necessary */
  	if (dso->last_find_result.addr >= sym->start &&
  	    (dso->last_find_result.addr < sym->end ||
  	    sym->start == sym->end)) {
  		dso->last_find_result.symbol = sym;
  	}
  }
  
  struct symbol *dso__find_symbol(struct dso *dso, u64 addr)
  {
  	if (dso->last_find_result.addr != addr || dso->last_find_result.symbol == NULL) {
  		dso->last_find_result.addr   = addr;
  		dso->last_find_result.symbol = symbols__find(&dso->symbols, addr);
  	}
  
  	return dso->last_find_result.symbol;
  }
  
  struct symbol *dso__first_symbol(struct dso *dso)
  {
  	return symbols__first(&dso->symbols);
  }
  
  struct symbol *dso__last_symbol(struct dso *dso)
  {
  	return symbols__last(&dso->symbols);
  }
  
  struct symbol *dso__next_symbol(struct symbol *sym)
  {
  	return symbols__next(sym);
  }
  
  struct symbol *symbol__next_by_name(struct symbol *sym)
  {
  	struct symbol_name_rb_node *s = container_of(sym, struct symbol_name_rb_node, sym);
  	struct rb_node *n = rb_next(&s->rb_node);
  
  	return n ? &rb_entry(n, struct symbol_name_rb_node, rb_node)->sym : NULL;
  }
  
   /*
    * Returns first symbol that matched with @name.
    */
  struct symbol *dso__find_symbol_by_name(struct dso *dso, const char *name)
  {
  	struct symbol *s = symbols__find_by_name(&dso->symbol_names, name,
  						 SYMBOL_TAG_INCLUDE__NONE);
  	if (!s)
  		s = symbols__find_by_name(&dso->symbol_names, name,
  					  SYMBOL_TAG_INCLUDE__DEFAULT_ONLY);
  	return s;
  }
  
  void dso__sort_by_name(struct dso *dso)
  {
  	dso__set_sorted_by_name(dso);
  	return symbols__sort_by_name(&dso->symbol_names, &dso->symbols);
  }
  
  int modules__parse(const char *filename, void *arg,
  		   int (*process_module)(void *arg, const char *name,
  					 u64 start, u64 size))
  {
  	char *line = NULL;
  	size_t n;
  	FILE *file;
  	int err = 0;
  
  	file = fopen(filename, "r");
  	if (file == NULL)
  		return -1;
  
  	while (1) {
  		char name[PATH_MAX];
  		u64 start, size;
  		char *sep, *endptr;
  		ssize_t line_len;
  
  		line_len = getline(&line, &n, file);
  		if (line_len < 0) {
  			if (feof(file))
  				break;
  			err = -1;
  			goto out;
  		}
  
  		if (!line) {
  			err = -1;
  			goto out;
  		}
  
  		line[--line_len] = '\0'; /* \n */
  
  		sep = strrchr(line, 'x');
  		if (sep == NULL)
  			continue;
  
  		hex2u64(sep + 1, &start);
  
  		sep = strchr(line, ' ');
  		if (sep == NULL)
  			continue;
  
  		*sep = '\0';
  
  		scnprintf(name, sizeof(name), "[%s]", line);
  
  		size = strtoul(sep + 1, &endptr, 0);
  		if (*endptr != ' ' && *endptr != '\t')
  			continue;
  
  		err = process_module(arg, name, start, size);
  		if (err)
  			break;
  	}
  out:
  	free(line);
  	fclose(file);
  	return err;
  }
  
  /*
   * These are symbols in the kernel image, so make sure that
   * sym is from a kernel DSO.
   */
  static bool symbol__is_idle(const char *name)
  {
  	const char * const idle_symbols[] = {
  		"cpu_idle",
  		"cpu_startup_entry",
  		"intel_idle",
  		"default_idle",
  		"native_safe_halt",
  		"enter_idle",
  		"exit_idle",
  		"mwait_idle",
  		"mwait_idle_with_hints",
  		"poll_idle",
  		"ppc64_runlatch_off",
  		"pseries_dedicated_idle_sleep",
  		NULL
  	};
  	int i;
  
  	for (i = 0; idle_symbols[i]; i++) {
  		if (!strcmp(idle_symbols[i], name))
  			return true;
  	}
  
  	return false;
  }
  
  static int map__process_kallsym_symbol(void *arg, const char *name,
  				       char type, u64 start)
  {
  	struct symbol *sym;
  	struct dso *dso = arg;
  	struct rb_root *root = &dso->symbols;
  
  	if (!symbol_type__filter(type))
  		return 0;
  
  	/*
  	 * module symbols are not sorted so we add all
  	 * symbols, setting length to 0, and rely on
  	 * symbols__fixup_end() to fix it up.
  	 */
  	sym = symbol__new(start, 0, kallsyms2elf_binding(type), kallsyms2elf_type(type), name);
  	if (sym == NULL)
  		return -ENOMEM;
  	/*
  	 * We will pass the symbols to the filter later, in
  	 * map__split_kallsyms, when we have split the maps per module
  	 */
  	__symbols__insert(root, sym, !strchr(name, '['));
  
  	return 0;
  }
  
  /*
   * Loads the function entries in /proc/kallsyms into kernel_map->dso,
   * so that we can in the next step set the symbol ->end address and then
   * call kernel_maps__split_kallsyms.
   */
  static int dso__load_all_kallsyms(struct dso *dso, const char *filename)
  {
  	return kallsyms__parse(filename, dso, map__process_kallsym_symbol);
  }
  
  static int map_groups__split_kallsyms_for_kcore(struct map_groups *kmaps, struct dso *dso)
  {
  	struct map *curr_map;
  	struct symbol *pos;
  	int count = 0;
  	struct rb_root old_root = dso->symbols;
  	struct rb_root *root = &dso->symbols;
  	struct rb_node *next = rb_first(root);
  
  	if (!kmaps)
  		return -1;
  
  	*root = RB_ROOT;
  
  	while (next) {
  		char *module;
  
  		pos = rb_entry(next, struct symbol, rb_node);
  		next = rb_next(&pos->rb_node);
  
  		rb_erase_init(&pos->rb_node, &old_root);
  
  		module = strchr(pos->name, '\t');
  		if (module)
  			*module = '\0';
  
  		curr_map = map_groups__find(kmaps, pos->start);
  
  		if (!curr_map) {
  			symbol__delete(pos);
  			continue;
  		}
  
  		pos->start -= curr_map->start - curr_map->pgoff;
  		if (pos->end)
  			pos->end -= curr_map->start - curr_map->pgoff;
  		symbols__insert(&curr_map->dso->symbols, pos);
  		++count;
  	}
  
  	/* Symbols have been adjusted */
  	dso->adjust_symbols = 1;
  
  	return count;
  }
  
  /*
   * Split the symbols into maps, making sure there are no overlaps, i.e. the
   * kernel range is broken in several maps, named [kernel].N, as we don't have
   * the original ELF section names vmlinux have.
   */
  static int map_groups__split_kallsyms(struct map_groups *kmaps, struct dso *dso, u64 delta,
  				      struct map *initial_map)
  {
  	struct machine *machine;
  	struct map *curr_map = initial_map;
  	struct symbol *pos;
  	int count = 0, moved = 0;
  	struct rb_root *root = &dso->symbols;
  	struct rb_node *next = rb_first(root);
  	int kernel_range = 0;
  	bool x86_64;
  
  	if (!kmaps)
  		return -1;
  
  	machine = kmaps->machine;
  
  	x86_64 = machine__is(machine, "x86_64");
  
  	while (next) {
  		char *module;
  
  		pos = rb_entry(next, struct symbol, rb_node);
  		next = rb_next(&pos->rb_node);
  
  		module = strchr(pos->name, '\t');
  		if (module) {
  			if (!symbol_conf.use_modules)
  				goto discard_symbol;
  
  			*module++ = '\0';
  
  			if (strcmp(curr_map->dso->short_name, module)) {
  				if (curr_map != initial_map &&
  				    dso->kernel == DSO_TYPE_GUEST_KERNEL &&
  				    machine__is_default_guest(machine)) {
  					/*
  					 * We assume all symbols of a module are
  					 * continuous in * kallsyms, so curr_map
  					 * points to a module and all its
  					 * symbols are in its kmap. Mark it as
  					 * loaded.
  					 */
  					dso__set_loaded(curr_map->dso);
  				}
  
  				curr_map = map_groups__find_by_name(kmaps, module);
  				if (curr_map == NULL) {
  					pr_debug("%s/proc/{kallsyms,modules} "
  					         "inconsistency while looking "
  						 "for \"%s\" module!\n",
  						 machine->root_dir, module);
  					curr_map = initial_map;
  					goto discard_symbol;
  				}
  
  				if (curr_map->dso->loaded &&
  				    !machine__is_default_guest(machine))
  					goto discard_symbol;
  			}
  			/*
  			 * So that we look just like we get from .ko files,
  			 * i.e. not prelinked, relative to initial_map->start.
  			 */
  			pos->start = curr_map->map_ip(curr_map, pos->start);
  			pos->end   = curr_map->map_ip(curr_map, pos->end);
  		} else if (x86_64 && is_entry_trampoline(pos->name)) {
  			/*
  			 * These symbols are not needed anymore since the
  			 * trampoline maps refer to the text section and it's
  			 * symbols instead. Avoid having to deal with
  			 * relocations, and the assumption that the first symbol
  			 * is the start of kernel text, by simply removing the
  			 * symbols at this point.
  			 */
  			goto discard_symbol;
  		} else if (curr_map != initial_map) {
  			char dso_name[PATH_MAX];
  			struct dso *ndso;
  
  			if (delta) {
  				/* Kernel was relocated at boot time */
  				pos->start -= delta;
  				pos->end -= delta;
  			}
  
  			if (count == 0) {
  				curr_map = initial_map;
  				goto add_symbol;
  			}
  
  			if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
  				snprintf(dso_name, sizeof(dso_name),
  					"[guest.kernel].%d",
  					kernel_range++);
  			else
  				snprintf(dso_name, sizeof(dso_name),
  					"[kernel].%d",
  					kernel_range++);
  
  			ndso = dso__new(dso_name);
  			if (ndso == NULL)
  				return -1;
  
  			ndso->kernel = dso->kernel;
  
  			curr_map = map__new2(pos->start, ndso);
  			if (curr_map == NULL) {
  				dso__put(ndso);
  				return -1;
  			}
  
  			curr_map->map_ip = curr_map->unmap_ip = identity__map_ip;
  			map_groups__insert(kmaps, curr_map);
  			++kernel_range;
  		} else if (delta) {
  			/* Kernel was relocated at boot time */
  			pos->start -= delta;
  			pos->end -= delta;
  		}
  add_symbol:
  		if (curr_map != initial_map) {
  			rb_erase(&pos->rb_node, root);
  			symbols__insert(&curr_map->dso->symbols, pos);
  			++moved;
  		} else
  			++count;
  
  		continue;
  discard_symbol:
  		rb_erase(&pos->rb_node, root);
  		symbol__delete(pos);
  	}
  
  	if (curr_map != initial_map &&
  	    dso->kernel == DSO_TYPE_GUEST_KERNEL &&
  	    machine__is_default_guest(kmaps->machine)) {
  		dso__set_loaded(curr_map->dso);
  	}
  
  	return count + moved;
  }
  
  bool symbol__restricted_filename(const char *filename,
  				 const char *restricted_filename)
  {
  	bool restricted = false;
  
  	if (symbol_conf.kptr_restrict) {
  		char *r = realpath(filename, NULL);
  
  		if (r != NULL) {
  			restricted = strcmp(r, restricted_filename) == 0;
  			free(r);
  			return restricted;
  		}
  	}
  
  	return restricted;
  }
  
  struct module_info {
  	struct rb_node rb_node;
  	char *name;
  	u64 start;
  };
  
  static void add_module(struct module_info *mi, struct rb_root *modules)
  {
  	struct rb_node **p = &modules->rb_node;
  	struct rb_node *parent = NULL;
  	struct module_info *m;
  
  	while (*p != NULL) {
  		parent = *p;
  		m = rb_entry(parent, struct module_info, rb_node);
  		if (strcmp(mi->name, m->name) < 0)
  			p = &(*p)->rb_left;
  		else
  			p = &(*p)->rb_right;
  	}
  	rb_link_node(&mi->rb_node, parent, p);
  	rb_insert_color(&mi->rb_node, modules);
  }
  
  static void delete_modules(struct rb_root *modules)
  {
  	struct module_info *mi;
  	struct rb_node *next = rb_first(modules);
  
  	while (next) {
  		mi = rb_entry(next, struct module_info, rb_node);
  		next = rb_next(&mi->rb_node);
  		rb_erase(&mi->rb_node, modules);
  		zfree(&mi->name);
  		free(mi);
  	}
  }
  
  static struct module_info *find_module(const char *name,
  				       struct rb_root *modules)
  {
  	struct rb_node *n = modules->rb_node;
  
  	while (n) {
  		struct module_info *m;
  		int cmp;
  
  		m = rb_entry(n, struct module_info, rb_node);
  		cmp = strcmp(name, m->name);
  		if (cmp < 0)
  			n = n->rb_left;
  		else if (cmp > 0)
  			n = n->rb_right;
  		else
  			return m;
  	}
  
  	return NULL;
  }
  
  static int __read_proc_modules(void *arg, const char *name, u64 start,
  			       u64 size __maybe_unused)
  {
  	struct rb_root *modules = arg;
  	struct module_info *mi;
  
  	mi = zalloc(sizeof(struct module_info));
  	if (!mi)
  		return -ENOMEM;
  
  	mi->name = strdup(name);
  	mi->start = start;
  
  	if (!mi->name) {
  		free(mi);
  		return -ENOMEM;
  	}
  
  	add_module(mi, modules);
  
  	return 0;
  }
  
  static int read_proc_modules(const char *filename, struct rb_root *modules)
  {
  	if (symbol__restricted_filename(filename, "/proc/modules"))
  		return -1;
  
  	if (modules__parse(filename, modules, __read_proc_modules)) {
  		delete_modules(modules);
  		return -1;
  	}
  
  	return 0;
  }
  
  int compare_proc_modules(const char *from, const char *to)
  {
  	struct rb_root from_modules = RB_ROOT;
  	struct rb_root to_modules = RB_ROOT;
  	struct rb_node *from_node, *to_node;
  	struct module_info *from_m, *to_m;
  	int ret = -1;
  
  	if (read_proc_modules(from, &from_modules))
  		return -1;
  
  	if (read_proc_modules(to, &to_modules))
  		goto out_delete_from;
  
  	from_node = rb_first(&from_modules);
  	to_node = rb_first(&to_modules);
  	while (from_node) {
  		if (!to_node)
  			break;
  
  		from_m = rb_entry(from_node, struct module_info, rb_node);
  		to_m = rb_entry(to_node, struct module_info, rb_node);
  
  		if (from_m->start != to_m->start ||
  		    strcmp(from_m->name, to_m->name))
  			break;
  
  		from_node = rb_next(from_node);
  		to_node = rb_next(to_node);
  	}
  
  	if (!from_node && !to_node)
  		ret = 0;
  
  	delete_modules(&to_modules);
  out_delete_from:
  	delete_modules(&from_modules);
  
  	return ret;
  }
  
  struct map *map_groups__first(struct map_groups *mg)
  {
  	return maps__first(&mg->maps);
  }
  
  static int do_validate_kcore_modules(const char *filename,
  				  struct map_groups *kmaps)
  {
  	struct rb_root modules = RB_ROOT;
  	struct map *old_map;
  	int err;
  
  	err = read_proc_modules(filename, &modules);
  	if (err)
  		return err;
  
  	old_map = map_groups__first(kmaps);
  	while (old_map) {
  		struct map *next = map_groups__next(old_map);
  		struct module_info *mi;
  
  		if (!__map__is_kmodule(old_map)) {
  			old_map = next;
  			continue;
  		}
  
  		/* Module must be in memory at the same address */
  		mi = find_module(old_map->dso->short_name, &modules);
  		if (!mi || mi->start != old_map->start) {
  			err = -EINVAL;
  			goto out;
  		}
  
  		old_map = next;
  	}
  out:
  	delete_modules(&modules);
  	return err;
  }
  
  /*
   * If kallsyms is referenced by name then we look for filename in the same
   * directory.
   */
  static bool filename_from_kallsyms_filename(char *filename,
  					    const char *base_name,
  					    const char *kallsyms_filename)
  {
  	char *name;
  
  	strcpy(filename, kallsyms_filename);
  	name = strrchr(filename, '/');
  	if (!name)
  		return false;
  
  	name += 1;
  
  	if (!strcmp(name, "kallsyms")) {
  		strcpy(name, base_name);
  		return true;
  	}
  
  	return false;
  }
  
  static int validate_kcore_modules(const char *kallsyms_filename,
  				  struct map *map)
  {
  	struct map_groups *kmaps = map__kmaps(map);
  	char modules_filename[PATH_MAX];
  
  	if (!kmaps)
  		return -EINVAL;
  
  	if (!filename_from_kallsyms_filename(modules_filename, "modules",
  					     kallsyms_filename))
  		return -EINVAL;
  
  	if (do_validate_kcore_modules(modules_filename, kmaps))
  		return -EINVAL;
  
  	return 0;
  }
  
  static int validate_kcore_addresses(const char *kallsyms_filename,
  				    struct map *map)
  {
  	struct kmap *kmap = map__kmap(map);
  
  	if (!kmap)
  		return -EINVAL;
  
  	if (kmap->ref_reloc_sym && kmap->ref_reloc_sym->name) {
  		u64 start;
  
  		if (kallsyms__get_function_start(kallsyms_filename,
  						 kmap->ref_reloc_sym->name, &start))
  			return -ENOENT;
  		if (start != kmap->ref_reloc_sym->addr)
  			return -EINVAL;
  	}
  
  	return validate_kcore_modules(kallsyms_filename, map);
  }
  
  struct kcore_mapfn_data {
  	struct dso *dso;
  	struct list_head maps;
  };
  
  static int kcore_mapfn(u64 start, u64 len, u64 pgoff, void *data)
  {
  	struct kcore_mapfn_data *md = data;
  	struct map *map;
  
  	map = map__new2(start, md->dso);
  	if (map == NULL)
  		return -ENOMEM;
  
  	map->end = map->start + len;
  	map->pgoff = pgoff;
  
  	list_add(&map->node, &md->maps);
  
  	return 0;
  }
  
  static int dso__load_kcore(struct dso *dso, struct map *map,
  			   const char *kallsyms_filename)
  {
  	struct map_groups *kmaps = map__kmaps(map);
  	struct kcore_mapfn_data md;
  	struct map *old_map, *new_map, *replacement_map = NULL;
  	struct machine *machine;
  	bool is_64_bit;
  	int err, fd;
  	char kcore_filename[PATH_MAX];
  	u64 stext;
  
  	if (!kmaps)
  		return -EINVAL;
  
  	machine = kmaps->machine;
  
  	/* This function requires that the map is the kernel map */
  	if (!__map__is_kernel(map))
  		return -EINVAL;
  
  	if (!filename_from_kallsyms_filename(kcore_filename, "kcore",
  					     kallsyms_filename))
  		return -EINVAL;
  
  	/* Modules and kernel must be present at their original addresses */
  	if (validate_kcore_addresses(kallsyms_filename, map))
  		return -EINVAL;
  
  	md.dso = dso;
  	INIT_LIST_HEAD(&md.maps);
  
  	fd = open(kcore_filename, O_RDONLY);
  	if (fd < 0) {
  		pr_debug("Failed to open %s. Note /proc/kcore requires CAP_SYS_RAWIO capability to access.\n",
  			 kcore_filename);
  		return -EINVAL;
  	}
  
  	/* Read new maps into temporary lists */
  	err = file__read_maps(fd, map->prot & PROT_EXEC, kcore_mapfn, &md,
  			      &is_64_bit);
  	if (err)
  		goto out_err;
  	dso->is_64_bit = is_64_bit;
  
  	if (list_empty(&md.maps)) {
  		err = -EINVAL;
  		goto out_err;
  	}
  
  	/* Remove old maps */
  	old_map = map_groups__first(kmaps);
  	while (old_map) {
  		struct map *next = map_groups__next(old_map);
  
  		if (old_map != map)
  			map_groups__remove(kmaps, old_map);
  		old_map = next;
  	}
  	machine->trampolines_mapped = false;
  
  	/* Find the kernel map using the '_stext' symbol */
  	if (!kallsyms__get_function_start(kallsyms_filename, "_stext", &stext)) {
  		list_for_each_entry(new_map, &md.maps, node) {
  			if (stext >= new_map->start && stext < new_map->end) {
  				replacement_map = new_map;
  				break;
  			}
  		}
  	}
  
  	if (!replacement_map)
  		replacement_map = list_entry(md.maps.next, struct map, node);
  
  	/* Add new maps */
  	while (!list_empty(&md.maps)) {
  		new_map = list_entry(md.maps.next, struct map, node);
  		list_del_init(&new_map->node);
  		if (new_map == replacement_map) {
  			map->start	= new_map->start;
  			map->end	= new_map->end;
  			map->pgoff	= new_map->pgoff;
  			map->map_ip	= new_map->map_ip;
  			map->unmap_ip	= new_map->unmap_ip;
  			/* Ensure maps are correctly ordered */
  			map__get(map);
  			map_groups__remove(kmaps, map);
  			map_groups__insert(kmaps, map);
  			map__put(map);
  		} else {
  			map_groups__insert(kmaps, new_map);
  		}
  
  		map__put(new_map);
  	}
  
  	if (machine__is(machine, "x86_64")) {
  		u64 addr;
  
  		/*
  		 * If one of the corresponding symbols is there, assume the
  		 * entry trampoline maps are too.
  		 */
  		if (!kallsyms__get_function_start(kallsyms_filename,
  						  ENTRY_TRAMPOLINE_NAME,
  						  &addr))
  			machine->trampolines_mapped = true;
  	}
  
  	/*
  	 * Set the data type and long name so that kcore can be read via
  	 * dso__data_read_addr().
  	 */
  	if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
  		dso->binary_type = DSO_BINARY_TYPE__GUEST_KCORE;
  	else
  		dso->binary_type = DSO_BINARY_TYPE__KCORE;
  	dso__set_long_name(dso, strdup(kcore_filename), true);
  
  	close(fd);
  
  	if (map->prot & PROT_EXEC)
  		pr_debug("Using %s for kernel object code\n", kcore_filename);
  	else
  		pr_debug("Using %s for kernel data\n", kcore_filename);
  
  	return 0;
  
  out_err:
  	while (!list_empty(&md.maps)) {
  		map = list_entry(md.maps.next, struct map, node);
  		list_del_init(&map->node);
  		map__put(map);
  	}
  	close(fd);
  	return -EINVAL;
  }
  
  /*
   * If the kernel is relocated at boot time, kallsyms won't match.  Compute the
   * delta based on the relocation reference symbol.
   */
  static int kallsyms__delta(struct kmap *kmap, const char *filename, u64 *delta)
  {
  	u64 addr;
  
  	if (!kmap->ref_reloc_sym || !kmap->ref_reloc_sym->name)
  		return 0;
  
  	if (kallsyms__get_function_start(filename, kmap->ref_reloc_sym->name, &addr))
  		return -1;
  
  	*delta = addr - kmap->ref_reloc_sym->addr;
  	return 0;
  }
  
  int __dso__load_kallsyms(struct dso *dso, const char *filename,
  			 struct map *map, bool no_kcore)
  {
  	struct kmap *kmap = map__kmap(map);
  	u64 delta = 0;
  
  	if (symbol__restricted_filename(filename, "/proc/kallsyms"))
  		return -1;
  
  	if (!kmap || !kmap->kmaps)
  		return -1;
  
  	if (dso__load_all_kallsyms(dso, filename) < 0)
  		return -1;
  
  	if (kallsyms__delta(kmap, filename, &delta))
  		return -1;
  
  	symbols__fixup_end(&dso->symbols);
  	symbols__fixup_duplicate(&dso->symbols);
  
  	if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
  		dso->symtab_type = DSO_BINARY_TYPE__GUEST_KALLSYMS;
  	else
  		dso->symtab_type = DSO_BINARY_TYPE__KALLSYMS;
  
  	if (!no_kcore && !dso__load_kcore(dso, map, filename))
  		return map_groups__split_kallsyms_for_kcore(kmap->kmaps, dso);
  	else
  		return map_groups__split_kallsyms(kmap->kmaps, dso, delta, map);
  }
  
  int dso__load_kallsyms(struct dso *dso, const char *filename,
  		       struct map *map)
  {
  	return __dso__load_kallsyms(dso, filename, map, false);
  }
  
  static int dso__load_perf_map(const char *map_path, struct dso *dso)
  {
  	char *line = NULL;
  	size_t n;
  	FILE *file;
  	int nr_syms = 0;
  
  	file = fopen(map_path, "r");
  	if (file == NULL)
  		goto out_failure;
  
  	while (!feof(file)) {
  		u64 start, size;
  		struct symbol *sym;
  		int line_len, len;
  
  		line_len = getline(&line, &n, file);
  		if (line_len < 0)
  			break;
  
  		if (!line)
  			goto out_failure;
  
  		line[--line_len] = '\0'; /* \n */
  
  		len = hex2u64(line, &start);
  
  		len++;
  		if (len + 2 >= line_len)
  			continue;
  
  		len += hex2u64(line + len, &size);
  
  		len++;
  		if (len + 2 >= line_len)
  			continue;
  
  		sym = symbol__new(start, size, STB_GLOBAL, STT_FUNC, line + len);
  
  		if (sym == NULL)
  			goto out_delete_line;
  
  		symbols__insert(&dso->symbols, sym);
  		nr_syms++;
  	}
  
  	free(line);
  	fclose(file);
  
  	return nr_syms;
  
  out_delete_line:
  	free(line);
  out_failure:
  	return -1;
  }
  
  static bool dso__is_compatible_symtab_type(struct dso *dso, bool kmod,
  					   enum dso_binary_type type)
  {
  	switch (type) {
  	case DSO_BINARY_TYPE__JAVA_JIT:
  	case DSO_BINARY_TYPE__DEBUGLINK:
  	case DSO_BINARY_TYPE__SYSTEM_PATH_DSO:
  	case DSO_BINARY_TYPE__FEDORA_DEBUGINFO:
  	case DSO_BINARY_TYPE__UBUNTU_DEBUGINFO:
  	case DSO_BINARY_TYPE__BUILDID_DEBUGINFO:
  	case DSO_BINARY_TYPE__OPENEMBEDDED_DEBUGINFO:
  		return !kmod && dso->kernel == DSO_TYPE_USER;
  
  	case DSO_BINARY_TYPE__KALLSYMS:
  	case DSO_BINARY_TYPE__VMLINUX:
  	case DSO_BINARY_TYPE__KCORE:
  		return dso->kernel == DSO_TYPE_KERNEL;
  
  	case DSO_BINARY_TYPE__GUEST_KALLSYMS:
  	case DSO_BINARY_TYPE__GUEST_VMLINUX:
  	case DSO_BINARY_TYPE__GUEST_KCORE:
  		return dso->kernel == DSO_TYPE_GUEST_KERNEL;
  
  	case DSO_BINARY_TYPE__GUEST_KMODULE:
  	case DSO_BINARY_TYPE__GUEST_KMODULE_COMP:
  	case DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE:
  	case DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP:
  		/*
  		 * kernel modules know their symtab type - it's set when
  		 * creating a module dso in machine__findnew_module_map().
  		 */
  		return kmod && dso->symtab_type == type;
  
  	case DSO_BINARY_TYPE__BUILD_ID_CACHE:
  	case DSO_BINARY_TYPE__BUILD_ID_CACHE_DEBUGINFO:
  		return true;
  
  	case DSO_BINARY_TYPE__NOT_FOUND:
  	default:
  		return false;
  	}
  }
  
  /* Checks for the existence of the perf-<pid>.map file in two different
   * locations.  First, if the process is a separate mount namespace, check in
   * that namespace using the pid of the innermost pid namespace.  If's not in a
   * namespace, or the file can't be found there, try in the mount namespace of
   * the tracing process using our view of its pid.
   */
  static int dso__find_perf_map(char *filebuf, size_t bufsz,
  			      struct nsinfo **nsip)
  {
  	struct nscookie nsc;
  	struct nsinfo *nsi;
  	struct nsinfo *nnsi;
  	int rc = -1;
  
  	nsi = *nsip;
  
  	if (nsi->need_setns) {
  		snprintf(filebuf, bufsz, "/tmp/perf-%d.map", nsi->nstgid);
  		nsinfo__mountns_enter(nsi, &nsc);
  		rc = access(filebuf, R_OK);
  		nsinfo__mountns_exit(&nsc);
  		if (rc == 0)
  			return rc;
  	}
  
  	nnsi = nsinfo__copy(nsi);
  	if (nnsi) {
  		nsinfo__put(nsi);
  
  		nnsi->need_setns = false;
  		snprintf(filebuf, bufsz, "/tmp/perf-%d.map", nnsi->tgid);
  		*nsip = nnsi;
  		rc = 0;
  	}
  
  	return rc;
  }
  
  int dso__load(struct dso *dso, struct map *map)
  {
  	char *name;
  	int ret = -1;
  	u_int i;
  	struct machine *machine;
  	char *root_dir = (char *) "";
  	int ss_pos = 0;
  	struct symsrc ss_[2];
  	struct symsrc *syms_ss = NULL, *runtime_ss = NULL;
  	bool kmod;
  	bool perfmap;
  	unsigned char build_id[BUILD_ID_SIZE];
  	struct nscookie nsc;
  	char newmapname[PATH_MAX];
  	const char *map_path = dso->long_name;
  
  	perfmap = strncmp(dso->name, "/tmp/perf-", 10) == 0;
  	if (perfmap) {
  		if (dso->nsinfo && (dso__find_perf_map(newmapname,
  		    sizeof(newmapname), &dso->nsinfo) == 0)) {
  			map_path = newmapname;
  		}
  	}
  
  	nsinfo__mountns_enter(dso->nsinfo, &nsc);
  	pthread_mutex_lock(&dso->lock);
  
  	/* check again under the dso->lock */
  	if (dso__loaded(dso)) {
  		ret = 1;
  		goto out;
  	}
  
  	if (map->groups && map->groups->machine)
  		machine = map->groups->machine;
  	else
  		machine = NULL;
  
  	if (dso->kernel) {
  		if (dso->kernel == DSO_TYPE_KERNEL)
  			ret = dso__load_kernel_sym(dso, map);
  		else if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
  			ret = dso__load_guest_kernel_sym(dso, map);
  
  		if (machine__is(machine, "x86_64"))
  			machine__map_x86_64_entry_trampolines(machine, dso);
  		goto out;
  	}
  
  	dso->adjust_symbols = 0;
  
  	if (perfmap) {
  		struct stat st;
  
  		if (lstat(map_path, &st) < 0)
  			goto out;
  
  		if (!symbol_conf.force && st.st_uid && (st.st_uid != geteuid())) {
  			pr_warning("File %s not owned by current user or root, "
  				   "ignoring it (use -f to override).\n", map_path);
  			goto out;
  		}
  
  		ret = dso__load_perf_map(map_path, dso);
  		dso->symtab_type = ret > 0 ? DSO_BINARY_TYPE__JAVA_JIT :
  					     DSO_BINARY_TYPE__NOT_FOUND;
  		goto out;
  	}
  
  	if (machine)
  		root_dir = machine->root_dir;
  
  	name = malloc(PATH_MAX);
  	if (!name)
  		goto out;
  
  	kmod = dso->symtab_type == DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE ||
  		dso->symtab_type == DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP ||
  		dso->symtab_type == DSO_BINARY_TYPE__GUEST_KMODULE ||
  		dso->symtab_type == DSO_BINARY_TYPE__GUEST_KMODULE_COMP;
  
  
  	/*
  	 * Read the build id if possible. This is required for
  	 * DSO_BINARY_TYPE__BUILDID_DEBUGINFO to work
  	 */
  	if (!dso->has_build_id &&
  	    is_regular_file(dso->long_name)) {
  	    __symbol__join_symfs(name, PATH_MAX, dso->long_name);
  	    if (filename__read_build_id(name, build_id, BUILD_ID_SIZE) > 0)
  		dso__set_build_id(dso, build_id);
  	}
  
  	/*
  	 * Iterate over candidate debug images.
  	 * Keep track of "interesting" ones (those which have a symtab, dynsym,
  	 * and/or opd section) for processing.
  	 */
  	for (i = 0; i < DSO_BINARY_TYPE__SYMTAB_CNT; i++) {
  		struct symsrc *ss = &ss_[ss_pos];
  		bool next_slot = false;
  		bool is_reg;
  		bool nsexit;
  		int sirc = -1;
  
  		enum dso_binary_type symtab_type = binary_type_symtab[i];
  
  		nsexit = (symtab_type == DSO_BINARY_TYPE__BUILD_ID_CACHE ||
  		    symtab_type == DSO_BINARY_TYPE__BUILD_ID_CACHE_DEBUGINFO);
  
  		if (!dso__is_compatible_symtab_type(dso, kmod, symtab_type))
  			continue;
  
  		if (dso__read_binary_type_filename(dso, symtab_type,
  						   root_dir, name, PATH_MAX))
  			continue;
  
  		if (nsexit)
  			nsinfo__mountns_exit(&nsc);
  
  		is_reg = is_regular_file(name);
  		if (is_reg)
  			sirc = symsrc__init(ss, dso, name, symtab_type);
  
  		if (nsexit)
  			nsinfo__mountns_enter(dso->nsinfo, &nsc);
  
  		if (!is_reg || sirc < 0)
  			continue;
  
  		if (!syms_ss && symsrc__has_symtab(ss)) {
  			syms_ss = ss;
  			next_slot = true;
  			if (!dso->symsrc_filename)
  				dso->symsrc_filename = strdup(name);
  		}
  
  		if (!runtime_ss && symsrc__possibly_runtime(ss)) {
  			runtime_ss = ss;
  			next_slot = true;
  		}
  
  		if (next_slot) {
  			ss_pos++;
  
  			if (syms_ss && runtime_ss)
  				break;
  		} else {
  			symsrc__destroy(ss);
  		}
  
  	}
  
  	if (!runtime_ss && !syms_ss)
  		goto out_free;
  
  	if (runtime_ss && !syms_ss) {
  		syms_ss = runtime_ss;
  	}
  
  	/* We'll have to hope for the best */
  	if (!runtime_ss && syms_ss)
  		runtime_ss = syms_ss;
  
  	if (syms_ss)
  		ret = dso__load_sym(dso, map, syms_ss, runtime_ss, kmod);
  	else
  		ret = -1;
  
  	if (ret > 0) {
  		int nr_plt;
  
  		nr_plt = dso__synthesize_plt_symbols(dso, runtime_ss);
  		if (nr_plt > 0)
  			ret += nr_plt;
  	}
  
  	for (; ss_pos > 0; ss_pos--)
  		symsrc__destroy(&ss_[ss_pos - 1]);
  out_free:
  	free(name);
  	if (ret < 0 && strstr(dso->name, " (deleted)") != NULL)
  		ret = 0;
  out:
  	dso__set_loaded(dso);
  	pthread_mutex_unlock(&dso->lock);
  	nsinfo__mountns_exit(&nsc);
  
  	return ret;
  }
  
  struct map *map_groups__find_by_name(struct map_groups *mg, const char *name)
  {
  	struct maps *maps = &mg->maps;
  	struct map *map;
  
  	down_read(&maps->lock);
  
  	for (map = maps__first(maps); map; map = map__next(map)) {
  		if (map->dso && strcmp(map->dso->short_name, name) == 0)
  			goto out_unlock;
  	}
  
  	map = NULL;
  
  out_unlock:
  	up_read(&maps->lock);
  	return map;
  }
  
  int dso__load_vmlinux(struct dso *dso, struct map *map,
  		      const char *vmlinux, bool vmlinux_allocated)
  {
  	int err = -1;
  	struct symsrc ss;
  	char symfs_vmlinux[PATH_MAX];
  	enum dso_binary_type symtab_type;
  
  	if (vmlinux[0] == '/')
  		snprintf(symfs_vmlinux, sizeof(symfs_vmlinux), "%s", vmlinux);
  	else
  		symbol__join_symfs(symfs_vmlinux, vmlinux);
  
  	if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
  		symtab_type = DSO_BINARY_TYPE__GUEST_VMLINUX;
  	else
  		symtab_type = DSO_BINARY_TYPE__VMLINUX;
  
  	if (symsrc__init(&ss, dso, symfs_vmlinux, symtab_type))
  		return -1;
  
  	err = dso__load_sym(dso, map, &ss, &ss, 0);
  	symsrc__destroy(&ss);
  
  	if (err > 0) {
  		if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
  			dso->binary_type = DSO_BINARY_TYPE__GUEST_VMLINUX;
  		else
  			dso->binary_type = DSO_BINARY_TYPE__VMLINUX;
  		dso__set_long_name(dso, vmlinux, vmlinux_allocated);
  		dso__set_loaded(dso);
  		pr_debug("Using %s for symbols\n", symfs_vmlinux);
  	}
  
  	return err;
  }
  
  int dso__load_vmlinux_path(struct dso *dso, struct map *map)
  {
  	int i, err = 0;
  	char *filename = NULL;
  
  	pr_debug("Looking at the vmlinux_path (%d entries long)\n",
  		 vmlinux_path__nr_entries + 1);
  
  	for (i = 0; i < vmlinux_path__nr_entries; ++i) {
  		err = dso__load_vmlinux(dso, map, vmlinux_path[i], false);
  		if (err > 0)
  			goto out;
  	}
  
  	if (!symbol_conf.ignore_vmlinux_buildid)
  		filename = dso__build_id_filename(dso, NULL, 0, false);
  	if (filename != NULL) {
  		err = dso__load_vmlinux(dso, map, filename, true);
  		if (err > 0)
  			goto out;
  		free(filename);
  	}
  out:
  	return err;
  }
  
  static bool visible_dir_filter(const char *name, struct dirent *d)
  {
  	if (d->d_type != DT_DIR)
  		return false;
  	return lsdir_no_dot_filter(name, d);
  }
  
  static int find_matching_kcore(struct map *map, char *dir, size_t dir_sz)
  {
  	char kallsyms_filename[PATH_MAX];
  	int ret = -1;
  	struct strlist *dirs;
  	struct str_node *nd;
  
  	dirs = lsdir(dir, visible_dir_filter);
  	if (!dirs)
  		return -1;
  
  	strlist__for_each_entry(nd, dirs) {
  		scnprintf(kallsyms_filename, sizeof(kallsyms_filename),
  			  "%s/%s/kallsyms", dir, nd->s);
  		if (!validate_kcore_addresses(kallsyms_filename, map)) {
  			strlcpy(dir, kallsyms_filename, dir_sz);
  			ret = 0;
  			break;
  		}
  	}
  
  	strlist__delete(dirs);
  
  	return ret;
  }
  
  /*
   * Use open(O_RDONLY) to check readability directly instead of access(R_OK)
   * since access(R_OK) only checks with real UID/GID but open() use effective
   * UID/GID and actual capabilities (e.g. /proc/kcore requires CAP_SYS_RAWIO).
   */
  static bool filename__readable(const char *file)
  {
  	int fd = open(file, O_RDONLY);
  	if (fd < 0)
  		return false;
  	close(fd);
  	return true;
  }
  
  static char *dso__find_kallsyms(struct dso *dso, struct map *map)
  {
  	u8 host_build_id[BUILD_ID_SIZE];
  	char sbuild_id[SBUILD_ID_SIZE];
  	bool is_host = false;
  	char path[PATH_MAX];
  
  	if (!dso->has_build_id) {
  		/*
  		 * Last resort, if we don't have a build-id and couldn't find
  		 * any vmlinux file, try the running kernel kallsyms table.
  		 */
  		goto proc_kallsyms;
  	}
  
  	if (sysfs__read_build_id("/sys/kernel/notes", host_build_id,
  				 sizeof(host_build_id)) == 0)
  		is_host = dso__build_id_equal(dso, host_build_id);
  
  	/* Try a fast path for /proc/kallsyms if possible */
  	if (is_host) {
  		/*
  		 * Do not check the build-id cache, unless we know we cannot use
  		 * /proc/kcore or module maps don't match to /proc/kallsyms.
  		 * To check readability of /proc/kcore, do not use access(R_OK)
  		 * since /proc/kcore requires CAP_SYS_RAWIO to read and access
  		 * can't check it.
  		 */
  		if (filename__readable("/proc/kcore") &&
  		    !validate_kcore_addresses("/proc/kallsyms", map))
  			goto proc_kallsyms;
  	}
  
  	build_id__sprintf(dso->build_id, sizeof(dso->build_id), sbuild_id);
  
  	/* Find kallsyms in build-id cache with kcore */
  	scnprintf(path, sizeof(path), "%s/%s/%s",
  		  buildid_dir, DSO__NAME_KCORE, sbuild_id);
  
  	if (!find_matching_kcore(map, path, sizeof(path)))
  		return strdup(path);
  
  	/* Use current /proc/kallsyms if possible */
  	if (is_host) {
  proc_kallsyms:
  		return strdup("/proc/kallsyms");
  	}
  
  	/* Finally, find a cache of kallsyms */
  	if (!build_id_cache__kallsyms_path(sbuild_id, path, sizeof(path))) {
  		pr_err("No kallsyms or vmlinux with build-id %s was found\n",
  		       sbuild_id);
  		return NULL;
  	}
  
  	return strdup(path);
  }
  
  static int dso__load_kernel_sym(struct dso *dso, struct map *map)
  {
  	int err;
  	const char *kallsyms_filename = NULL;
  	char *kallsyms_allocated_filename = NULL;
  	/*
  	 * Step 1: if the user specified a kallsyms or vmlinux filename, use
  	 * it and only it, reporting errors to the user if it cannot be used.
  	 *
  	 * For instance, try to analyse an ARM perf.data file _without_ a
  	 * build-id, or if the user specifies the wrong path to the right
  	 * vmlinux file, obviously we can't fallback to another vmlinux (a
  	 * x86_86 one, on the machine where analysis is being performed, say),
  	 * or worse, /proc/kallsyms.
  	 *
  	 * If the specified file _has_ a build-id and there is a build-id
  	 * section in the perf.data file, we will still do the expected
  	 * validation in dso__load_vmlinux and will bail out if they don't
  	 * match.
  	 */
  	if (symbol_conf.kallsyms_name != NULL) {
  		kallsyms_filename = symbol_conf.kallsyms_name;
  		goto do_kallsyms;
  	}
  
  	if (!symbol_conf.ignore_vmlinux && symbol_conf.vmlinux_name != NULL) {
  		return dso__load_vmlinux(dso, map, symbol_conf.vmlinux_name, false);
  	}
  
  	if (!symbol_conf.ignore_vmlinux && vmlinux_path != NULL) {
  		err = dso__load_vmlinux_path(dso, map);
  		if (err > 0)
  			return err;
  	}
  
  	/* do not try local files if a symfs was given */
  	if (symbol_conf.symfs[0] != 0)
  		return -1;
  
  	kallsyms_allocated_filename = dso__find_kallsyms(dso, map);
  	if (!kallsyms_allocated_filename)
  		return -1;
  
  	kallsyms_filename = kallsyms_allocated_filename;
  
  do_kallsyms:
  	err = dso__load_kallsyms(dso, kallsyms_filename, map);
  	if (err > 0)
  		pr_debug("Using %s for symbols\n", kallsyms_filename);
  	free(kallsyms_allocated_filename);
  
  	if (err > 0 && !dso__is_kcore(dso)) {
  		dso->binary_type = DSO_BINARY_TYPE__KALLSYMS;
  		dso__set_long_name(dso, DSO__NAME_KALLSYMS, false);
  		map__fixup_start(map);
  		map__fixup_end(map);
  	}
  
  	return err;
  }
  
  static int dso__load_guest_kernel_sym(struct dso *dso, struct map *map)
  {
  	int err;
  	const char *kallsyms_filename = NULL;
  	struct machine *machine;
  	char path[PATH_MAX];
  
  	if (!map->groups) {
  		pr_debug("Guest kernel map hasn't the point to groups\n");
  		return -1;
  	}
  	machine = map->groups->machine;
  
  	if (machine__is_default_guest(machine)) {
  		/*
  		 * if the user specified a vmlinux filename, use it and only
  		 * it, reporting errors to the user if it cannot be used.
  		 * Or use file guest_kallsyms inputted by user on commandline
  		 */
  		if (symbol_conf.default_guest_vmlinux_name != NULL) {
  			err = dso__load_vmlinux(dso, map,
  						symbol_conf.default_guest_vmlinux_name,
  						false);
  			return err;
  		}
  
  		kallsyms_filename = symbol_conf.default_guest_kallsyms;
  		if (!kallsyms_filename)
  			return -1;
  	} else {
  		sprintf(path, "%s/proc/kallsyms", machine->root_dir);
  		kallsyms_filename = path;
  	}
  
  	err = dso__load_kallsyms(dso, kallsyms_filename, map);
  	if (err > 0)
  		pr_debug("Using %s for symbols\n", kallsyms_filename);
  	if (err > 0 && !dso__is_kcore(dso)) {
  		dso->binary_type = DSO_BINARY_TYPE__GUEST_KALLSYMS;
  		dso__set_long_name(dso, machine->mmap_name, false);
  		map__fixup_start(map);
  		map__fixup_end(map);
  	}
  
  	return err;
  }
  
  static void vmlinux_path__exit(void)
  {
  	while (--vmlinux_path__nr_entries >= 0)
  		zfree(&vmlinux_path[vmlinux_path__nr_entries]);
  	vmlinux_path__nr_entries = 0;
  
  	zfree(&vmlinux_path);
  }
  
  static const char * const vmlinux_paths[] = {
  	"vmlinux",
  	"/boot/vmlinux"
  };
  
  static const char * const vmlinux_paths_upd[] = {
  	"/boot/vmlinux-%s",
  	"/usr/lib/debug/boot/vmlinux-%s",
  	"/lib/modules/%s/build/vmlinux",
  	"/usr/lib/debug/lib/modules/%s/vmlinux",
  	"/usr/lib/debug/boot/vmlinux-%s.debug"
  };
  
  static int vmlinux_path__add(const char *new_entry)
  {
  	vmlinux_path[vmlinux_path__nr_entries] = strdup(new_entry);
  	if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
  		return -1;
  	++vmlinux_path__nr_entries;
  
  	return 0;
  }
  
  static int vmlinux_path__init(struct perf_env *env)
  {
  	struct utsname uts;
  	char bf[PATH_MAX];
  	char *kernel_version;
  	unsigned int i;
  
  	vmlinux_path = malloc(sizeof(char *) * (ARRAY_SIZE(vmlinux_paths) +
  			      ARRAY_SIZE(vmlinux_paths_upd)));
  	if (vmlinux_path == NULL)
  		return -1;
  
  	for (i = 0; i < ARRAY_SIZE(vmlinux_paths); i++)
  		if (vmlinux_path__add(vmlinux_paths[i]) < 0)
  			goto out_fail;
  
  	/* only try kernel version if no symfs was given */
  	if (symbol_conf.symfs[0] != 0)
  		return 0;
  
  	if (env) {
  		kernel_version = env->os_release;
  	} else {
  		if (uname(&uts) < 0)
  			goto out_fail;
  
  		kernel_version = uts.release;
  	}
  
  	for (i = 0; i < ARRAY_SIZE(vmlinux_paths_upd); i++) {
  		snprintf(bf, sizeof(bf), vmlinux_paths_upd[i], kernel_version);
  		if (vmlinux_path__add(bf) < 0)
  			goto out_fail;
  	}
  
  	return 0;
  
  out_fail:
  	vmlinux_path__exit();
  	return -1;
  }
  
  int setup_list(struct strlist **list, const char *list_str,
  		      const char *list_name)
  {
  	if (list_str == NULL)
  		return 0;
  
  	*list = strlist__new(list_str, NULL);
  	if (!*list) {
  		pr_err("problems parsing %s list\n", list_name);
  		return -1;
  	}
  
  	symbol_conf.has_filter = true;
  	return 0;
  }
  
  int setup_intlist(struct intlist **list, const char *list_str,
  		  const char *list_name)
  {
  	if (list_str == NULL)
  		return 0;
  
  	*list = intlist__new(list_str);
  	if (!*list) {
  		pr_err("problems parsing %s list\n", list_name);
  		return -1;
  	}
  	return 0;
  }
  
  static bool symbol__read_kptr_restrict(void)
  {
  	bool value = false;
  	FILE *fp = fopen("/proc/sys/kernel/kptr_restrict", "r");
  
  	if (fp != NULL) {
  		char line[8];
  
  		if (fgets(line, sizeof(line), fp) != NULL)
  			value = ((geteuid() != 0) || (getuid() != 0)) ?
  					(atoi(line) != 0) :
  					(atoi(line) == 2);
  
  		fclose(fp);
  	}
  
  	return value;
  }
  
  int symbol__annotation_init(void)
  {
  	if (symbol_conf.init_annotation)
  		return 0;
  
  	if (symbol_conf.initialized) {
  		pr_err("Annotation needs to be init before symbol__init()\n");
  		return -1;
  	}
  
  	symbol_conf.priv_size += sizeof(struct annotation);
  	symbol_conf.init_annotation = true;
  	return 0;
  }
  
  int symbol__init(struct perf_env *env)
  {
  	const char *symfs;
  
  	if (symbol_conf.initialized)
  		return 0;
  
  	symbol_conf.priv_size = PERF_ALIGN(symbol_conf.priv_size, sizeof(u64));
  
  	symbol__elf_init();
  
  	if (symbol_conf.sort_by_name)
  		symbol_conf.priv_size += (sizeof(struct symbol_name_rb_node) -
  					  sizeof(struct symbol));
  
  	if (symbol_conf.try_vmlinux_path && vmlinux_path__init(env) < 0)
  		return -1;
  
  	if (symbol_conf.field_sep && *symbol_conf.field_sep == '.') {
  		pr_err("'.' is the only non valid --field-separator argument\n");
  		return -1;
  	}
  
  	if (setup_list(&symbol_conf.dso_list,
  		       symbol_conf.dso_list_str, "dso") < 0)
  		return -1;
  
  	if (setup_list(&symbol_conf.comm_list,
  		       symbol_conf.comm_list_str, "comm") < 0)
  		goto out_free_dso_list;
  
  	if (setup_intlist(&symbol_conf.pid_list,
  		       symbol_conf.pid_list_str, "pid") < 0)
  		goto out_free_comm_list;
  
  	if (setup_intlist(&symbol_conf.tid_list,
  		       symbol_conf.tid_list_str, "tid") < 0)
  		goto out_free_pid_list;
  
  	if (setup_list(&symbol_conf.sym_list,
  		       symbol_conf.sym_list_str, "symbol") < 0)
  		goto out_free_tid_list;
  
  	if (setup_list(&symbol_conf.bt_stop_list,
  		       symbol_conf.bt_stop_list_str, "symbol") < 0)
  		goto out_free_sym_list;
  
  	/*
  	 * A path to symbols of "/" is identical to ""
  	 * reset here for simplicity.
  	 */
  	symfs = realpath(symbol_conf.symfs, NULL);
  	if (symfs == NULL)
  		symfs = symbol_conf.symfs;
  	if (strcmp(symfs, "/") == 0)
  		symbol_conf.symfs = "";
  	if (symfs != symbol_conf.symfs)
  		free((void *)symfs);
  
  	symbol_conf.kptr_restrict = symbol__read_kptr_restrict();
  
  	symbol_conf.initialized = true;
  	return 0;
  
  out_free_sym_list:
  	strlist__delete(symbol_conf.sym_list);
  out_free_tid_list:
  	intlist__delete(symbol_conf.tid_list);
  out_free_pid_list:
  	intlist__delete(symbol_conf.pid_list);
  out_free_comm_list:
  	strlist__delete(symbol_conf.comm_list);
  out_free_dso_list:
  	strlist__delete(symbol_conf.dso_list);
  	return -1;
  }
  
  void symbol__exit(void)
  {
  	if (!symbol_conf.initialized)
  		return;
  	strlist__delete(symbol_conf.bt_stop_list);
  	strlist__delete(symbol_conf.sym_list);
  	strlist__delete(symbol_conf.dso_list);
  	strlist__delete(symbol_conf.comm_list);
  	intlist__delete(symbol_conf.tid_list);
  	intlist__delete(symbol_conf.pid_list);
  	vmlinux_path__exit();
  	symbol_conf.sym_list = symbol_conf.dso_list = symbol_conf.comm_list = NULL;
  	symbol_conf.bt_stop_list = NULL;
  	symbol_conf.initialized = false;
  }
  
  int symbol__config_symfs(const struct option *opt __maybe_unused,
  			 const char *dir, int unset __maybe_unused)
  {
  	char *bf = NULL;
  	int ret;
  
  	symbol_conf.symfs = strdup(dir);
  	if (symbol_conf.symfs == NULL)
  		return -ENOMEM;
  
  	/* skip the locally configured cache if a symfs is given, and
  	 * config buildid dir to symfs/.debug
  	 */
  	ret = asprintf(&bf, "%s/%s", dir, ".debug");
  	if (ret < 0)
  		return -ENOMEM;
  
  	set_buildid_dir(bf);
  
  	free(bf);
  	return 0;
  }
  
  struct mem_info *mem_info__get(struct mem_info *mi)
  {
  	if (mi)
  		refcount_inc(&mi->refcnt);
  	return mi;
  }
  
  void mem_info__put(struct mem_info *mi)
  {
  	if (mi && refcount_dec_and_test(&mi->refcnt))
  		free(mi);
  }
  
  struct mem_info *mem_info__new(void)
  {
  	struct mem_info *mi = zalloc(sizeof(*mi));
  
  	if (mi)
  		refcount_set(&mi->refcnt, 1);
  	return mi;
  }
  