9 #include "demangle-java.h"
10 #include "demangle-rust.h"
13 #include <symbol/kallsyms.h>
17 #define EM_AARCH64 183 /* ARM 64 bit */
20 typedef Elf64_Nhdr GElf_Nhdr;
22 #ifdef HAVE_CPLUS_DEMANGLE_SUPPORT
23 extern char *cplus_demangle(const char *, int);
25 static inline char *bfd_demangle(void __maybe_unused *v, const char *c, int i)
27 return cplus_demangle(c, i);
31 static inline char *bfd_demangle(void __maybe_unused *v,
32 const char __maybe_unused *c,
38 #define PACKAGE 'perf'
43 #ifndef HAVE_ELF_GETPHDRNUM_SUPPORT
44 static int elf_getphdrnum(Elf *elf, size_t *dst)
49 ehdr = gelf_getehdr(elf, &gehdr);
59 #ifndef HAVE_ELF_GETSHDRSTRNDX_SUPPORT
60 static int elf_getshdrstrndx(Elf *elf __maybe_unused, size_t *dst __maybe_unused)
62 pr_err("%s: update your libelf to > 0.140, this one lacks elf_getshdrstrndx().\n", __func__);
67 #ifndef NT_GNU_BUILD_ID
68 #define NT_GNU_BUILD_ID 3
72 * elf_symtab__for_each_symbol - iterate thru all the symbols
74 * @syms: struct elf_symtab instance to iterate
76 * @sym: GElf_Sym iterator
78 #define elf_symtab__for_each_symbol(syms, nr_syms, idx, sym) \
79 for (idx = 0, gelf_getsym(syms, idx, &sym);\
81 idx++, gelf_getsym(syms, idx, &sym))
83 static inline uint8_t elf_sym__type(const GElf_Sym *sym)
85 return GELF_ST_TYPE(sym->st_info);
89 #define STT_GNU_IFUNC 10
92 static inline int elf_sym__is_function(const GElf_Sym *sym)
94 return (elf_sym__type(sym) == STT_FUNC ||
95 elf_sym__type(sym) == STT_GNU_IFUNC) &&
97 sym->st_shndx != SHN_UNDEF;
100 static inline bool elf_sym__is_object(const GElf_Sym *sym)
102 return elf_sym__type(sym) == STT_OBJECT &&
104 sym->st_shndx != SHN_UNDEF;
107 static inline int elf_sym__is_label(const GElf_Sym *sym)
109 return elf_sym__type(sym) == STT_NOTYPE &&
111 sym->st_shndx != SHN_UNDEF &&
112 sym->st_shndx != SHN_ABS;
115 static bool elf_sym__is_a(GElf_Sym *sym, enum map_type type)
119 return elf_sym__is_function(sym);
121 return elf_sym__is_object(sym);
127 static inline const char *elf_sym__name(const GElf_Sym *sym,
128 const Elf_Data *symstrs)
130 return symstrs->d_buf + sym->st_name;
133 static inline const char *elf_sec__name(const GElf_Shdr *shdr,
134 const Elf_Data *secstrs)
136 return secstrs->d_buf + shdr->sh_name;
139 static inline int elf_sec__is_text(const GElf_Shdr *shdr,
140 const Elf_Data *secstrs)
142 return strstr(elf_sec__name(shdr, secstrs), "text") != NULL;
145 static inline bool elf_sec__is_data(const GElf_Shdr *shdr,
146 const Elf_Data *secstrs)
148 return strstr(elf_sec__name(shdr, secstrs), "data") != NULL;
151 static bool elf_sec__is_a(GElf_Shdr *shdr, Elf_Data *secstrs,
156 return elf_sec__is_text(shdr, secstrs);
158 return elf_sec__is_data(shdr, secstrs);
164 static size_t elf_addr_to_index(Elf *elf, GElf_Addr addr)
170 while ((sec = elf_nextscn(elf, sec)) != NULL) {
171 gelf_getshdr(sec, &shdr);
173 if ((addr >= shdr.sh_addr) &&
174 (addr < (shdr.sh_addr + shdr.sh_size)))
183 Elf_Scn *elf_section_by_name(Elf *elf, GElf_Ehdr *ep,
184 GElf_Shdr *shp, const char *name, size_t *idx)
189 /* Elf is corrupted/truncated, avoid calling elf_strptr. */
190 if (!elf_rawdata(elf_getscn(elf, ep->e_shstrndx), NULL))
193 while ((sec = elf_nextscn(elf, sec)) != NULL) {
196 gelf_getshdr(sec, shp);
197 str = elf_strptr(elf, ep->e_shstrndx, shp->sh_name);
198 if (str && !strcmp(name, str)) {
209 #define elf_section__for_each_rel(reldata, pos, pos_mem, idx, nr_entries) \
210 for (idx = 0, pos = gelf_getrel(reldata, 0, &pos_mem); \
212 ++idx, pos = gelf_getrel(reldata, idx, &pos_mem))
214 #define elf_section__for_each_rela(reldata, pos, pos_mem, idx, nr_entries) \
215 for (idx = 0, pos = gelf_getrela(reldata, 0, &pos_mem); \
217 ++idx, pos = gelf_getrela(reldata, idx, &pos_mem))
220 * We need to check if we have a .dynsym, so that we can handle the
221 * .plt, synthesizing its symbols, that aren't on the symtabs (be it
222 * .dynsym or .symtab).
223 * And always look at the original dso, not at debuginfo packages, that
224 * have the PLT data stripped out (shdr_rel_plt.sh_type == SHT_NOBITS).
226 int dso__synthesize_plt_symbols(struct dso *dso, struct symsrc *ss, struct map *map,
227 symbol_filter_t filter)
229 uint32_t nr_rel_entries, idx;
234 GElf_Shdr shdr_rel_plt, shdr_dynsym;
235 Elf_Data *reldata, *syms, *symstrs;
236 Elf_Scn *scn_plt_rel, *scn_symstrs, *scn_dynsym;
239 char sympltname[1024];
241 int nr = 0, symidx, err = 0;
249 scn_dynsym = ss->dynsym;
250 shdr_dynsym = ss->dynshdr;
251 dynsym_idx = ss->dynsym_idx;
253 if (scn_dynsym == NULL)
256 scn_plt_rel = elf_section_by_name(elf, &ehdr, &shdr_rel_plt,
258 if (scn_plt_rel == NULL) {
259 scn_plt_rel = elf_section_by_name(elf, &ehdr, &shdr_rel_plt,
261 if (scn_plt_rel == NULL)
267 if (shdr_rel_plt.sh_link != dynsym_idx)
270 if (elf_section_by_name(elf, &ehdr, &shdr_plt, ".plt", NULL) == NULL)
274 * Fetch the relocation section to find the idxes to the GOT
275 * and the symbols in the .dynsym they refer to.
277 reldata = elf_getdata(scn_plt_rel, NULL);
281 syms = elf_getdata(scn_dynsym, NULL);
285 scn_symstrs = elf_getscn(elf, shdr_dynsym.sh_link);
286 if (scn_symstrs == NULL)
289 symstrs = elf_getdata(scn_symstrs, NULL);
293 if (symstrs->d_size == 0)
296 nr_rel_entries = shdr_rel_plt.sh_size / shdr_rel_plt.sh_entsize;
297 plt_offset = shdr_plt.sh_offset;
299 if (shdr_rel_plt.sh_type == SHT_RELA) {
300 GElf_Rela pos_mem, *pos;
302 elf_section__for_each_rela(reldata, pos, pos_mem, idx,
304 symidx = GELF_R_SYM(pos->r_info);
305 plt_offset += shdr_plt.sh_entsize;
306 gelf_getsym(syms, symidx, &sym);
307 snprintf(sympltname, sizeof(sympltname),
308 "%s@plt", elf_sym__name(&sym, symstrs));
310 f = symbol__new(plt_offset, shdr_plt.sh_entsize,
311 STB_GLOBAL, sympltname);
315 if (filter && filter(map, f))
318 symbols__insert(&dso->symbols[map->type], f);
322 } else if (shdr_rel_plt.sh_type == SHT_REL) {
323 GElf_Rel pos_mem, *pos;
324 elf_section__for_each_rel(reldata, pos, pos_mem, idx,
326 symidx = GELF_R_SYM(pos->r_info);
327 plt_offset += shdr_plt.sh_entsize;
328 gelf_getsym(syms, symidx, &sym);
329 snprintf(sympltname, sizeof(sympltname),
330 "%s@plt", elf_sym__name(&sym, symstrs));
332 f = symbol__new(plt_offset, shdr_plt.sh_entsize,
333 STB_GLOBAL, sympltname);
337 if (filter && filter(map, f))
340 symbols__insert(&dso->symbols[map->type], f);
350 pr_debug("%s: problems reading %s PLT info.\n",
351 __func__, dso->long_name);
356 * Align offset to 4 bytes as needed for note name and descriptor data.
358 #define NOTE_ALIGN(n) (((n) + 3) & -4U)
360 static int elf_read_build_id(Elf *elf, void *bf, size_t size)
370 if (size < BUILD_ID_SIZE)
377 if (gelf_getehdr(elf, &ehdr) == NULL) {
378 pr_err("%s: cannot get elf header.\n", __func__);
383 * Check following sections for notes:
384 * '.note.gnu.build-id'
386 * '.note' (VDSO specific)
389 sec = elf_section_by_name(elf, &ehdr, &shdr,
390 ".note.gnu.build-id", NULL);
394 sec = elf_section_by_name(elf, &ehdr, &shdr,
399 sec = elf_section_by_name(elf, &ehdr, &shdr,
408 data = elf_getdata(sec, NULL);
413 while (ptr < (data->d_buf + data->d_size)) {
414 GElf_Nhdr *nhdr = ptr;
415 size_t namesz = NOTE_ALIGN(nhdr->n_namesz),
416 descsz = NOTE_ALIGN(nhdr->n_descsz);
419 ptr += sizeof(*nhdr);
422 if (nhdr->n_type == NT_GNU_BUILD_ID &&
423 nhdr->n_namesz == sizeof("GNU")) {
424 if (memcmp(name, "GNU", sizeof("GNU")) == 0) {
425 size_t sz = min(size, descsz);
427 memset(bf + sz, 0, size - sz);
439 int filename__read_build_id(const char *filename, void *bf, size_t size)
444 if (size < BUILD_ID_SIZE)
447 fd = open(filename, O_RDONLY);
451 elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL);
453 pr_debug2("%s: cannot read %s ELF file.\n", __func__, filename);
457 err = elf_read_build_id(elf, bf, size);
466 int sysfs__read_build_id(const char *filename, void *build_id, size_t size)
470 if (size < BUILD_ID_SIZE)
473 fd = open(filename, O_RDONLY);
480 size_t namesz, descsz;
482 if (read(fd, &nhdr, sizeof(nhdr)) != sizeof(nhdr))
485 namesz = NOTE_ALIGN(nhdr.n_namesz);
486 descsz = NOTE_ALIGN(nhdr.n_descsz);
487 if (nhdr.n_type == NT_GNU_BUILD_ID &&
488 nhdr.n_namesz == sizeof("GNU")) {
489 if (read(fd, bf, namesz) != (ssize_t)namesz)
491 if (memcmp(bf, "GNU", sizeof("GNU")) == 0) {
492 size_t sz = min(descsz, size);
493 if (read(fd, build_id, sz) == (ssize_t)sz) {
494 memset(build_id + sz, 0, size - sz);
498 } else if (read(fd, bf, descsz) != (ssize_t)descsz)
501 int n = namesz + descsz;
502 if (read(fd, bf, n) != n)
511 int filename__read_debuglink(const char *filename, char *debuglink,
522 fd = open(filename, O_RDONLY);
526 elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL);
528 pr_debug2("%s: cannot read %s ELF file.\n", __func__, filename);
536 if (gelf_getehdr(elf, &ehdr) == NULL) {
537 pr_err("%s: cannot get elf header.\n", __func__);
541 sec = elf_section_by_name(elf, &ehdr, &shdr,
542 ".gnu_debuglink", NULL);
546 data = elf_getdata(sec, NULL);
550 /* the start of this section is a zero-terminated string */
551 strncpy(debuglink, data->d_buf, size);
563 static int dso__swap_init(struct dso *dso, unsigned char eidata)
565 static unsigned int const endian = 1;
567 dso->needs_swap = DSO_SWAP__NO;
571 /* We are big endian, DSO is little endian. */
572 if (*(unsigned char const *)&endian != 1)
573 dso->needs_swap = DSO_SWAP__YES;
577 /* We are little endian, DSO is big endian. */
578 if (*(unsigned char const *)&endian != 0)
579 dso->needs_swap = DSO_SWAP__YES;
583 pr_err("unrecognized DSO data encoding %d\n", eidata);
590 static int decompress_kmodule(struct dso *dso, const char *name,
591 enum dso_binary_type type)
594 char tmpbuf[] = "/tmp/perf-kmod-XXXXXX";
597 if (type != DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP &&
598 type != DSO_BINARY_TYPE__GUEST_KMODULE_COMP &&
599 type != DSO_BINARY_TYPE__BUILD_ID_CACHE)
602 if (type == DSO_BINARY_TYPE__BUILD_ID_CACHE)
603 name = dso->long_name;
605 if (kmod_path__parse_ext(&m, name) || !m.comp)
608 fd = mkstemp(tmpbuf);
610 dso->load_errno = errno;
614 if (!decompress_to_file(m.ext, name, fd)) {
615 dso->load_errno = DSO_LOAD_ERRNO__DECOMPRESSION_FAILURE;
627 bool symsrc__possibly_runtime(struct symsrc *ss)
629 return ss->dynsym || ss->opdsec;
632 bool symsrc__has_symtab(struct symsrc *ss)
634 return ss->symtab != NULL;
637 void symsrc__destroy(struct symsrc *ss)
644 bool __weak elf__needs_adjust_symbols(GElf_Ehdr ehdr)
646 return ehdr.e_type == ET_EXEC || ehdr.e_type == ET_REL;
649 int symsrc__init(struct symsrc *ss, struct dso *dso, const char *name,
650 enum dso_binary_type type)
657 if (dso__needs_decompress(dso)) {
658 fd = decompress_kmodule(dso, name, type);
662 fd = open(name, O_RDONLY);
664 dso->load_errno = errno;
669 elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL);
671 pr_debug("%s: cannot read %s ELF file.\n", __func__, name);
672 dso->load_errno = DSO_LOAD_ERRNO__INVALID_ELF;
676 if (gelf_getehdr(elf, &ehdr) == NULL) {
677 dso->load_errno = DSO_LOAD_ERRNO__INVALID_ELF;
678 pr_debug("%s: cannot get elf header.\n", __func__);
682 if (dso__swap_init(dso, ehdr.e_ident[EI_DATA])) {
683 dso->load_errno = DSO_LOAD_ERRNO__INTERNAL_ERROR;
687 /* Always reject images with a mismatched build-id: */
688 if (dso->has_build_id) {
689 u8 build_id[BUILD_ID_SIZE];
691 if (elf_read_build_id(elf, build_id, BUILD_ID_SIZE) < 0) {
692 dso->load_errno = DSO_LOAD_ERRNO__CANNOT_READ_BUILDID;
696 if (!dso__build_id_equal(dso, build_id)) {
697 pr_debug("%s: build id mismatch for %s.\n", __func__, name);
698 dso->load_errno = DSO_LOAD_ERRNO__MISMATCHING_BUILDID;
703 ss->is_64_bit = (gelf_getclass(elf) == ELFCLASS64);
705 ss->symtab = elf_section_by_name(elf, &ehdr, &ss->symshdr, ".symtab",
707 if (ss->symshdr.sh_type != SHT_SYMTAB)
711 ss->dynsym = elf_section_by_name(elf, &ehdr, &ss->dynshdr, ".dynsym",
713 if (ss->dynshdr.sh_type != SHT_DYNSYM)
717 ss->opdsec = elf_section_by_name(elf, &ehdr, &ss->opdshdr, ".opd",
719 if (ss->opdshdr.sh_type != SHT_PROGBITS)
722 if (dso->kernel == DSO_TYPE_USER)
723 ss->adjust_symbols = true;
725 ss->adjust_symbols = elf__needs_adjust_symbols(ehdr);
727 ss->name = strdup(name);
729 dso->load_errno = errno;
748 * ref_reloc_sym_not_found - has kernel relocation symbol been found.
749 * @kmap: kernel maps and relocation reference symbol
751 * This function returns %true if we are dealing with the kernel maps and the
752 * relocation reference symbol has not yet been found. Otherwise %false is
755 static bool ref_reloc_sym_not_found(struct kmap *kmap)
757 return kmap && kmap->ref_reloc_sym && kmap->ref_reloc_sym->name &&
758 !kmap->ref_reloc_sym->unrelocated_addr;
762 * ref_reloc - kernel relocation offset.
763 * @kmap: kernel maps and relocation reference symbol
765 * This function returns the offset of kernel addresses as determined by using
766 * the relocation reference symbol i.e. if the kernel has not been relocated
767 * then the return value is zero.
769 static u64 ref_reloc(struct kmap *kmap)
771 if (kmap && kmap->ref_reloc_sym &&
772 kmap->ref_reloc_sym->unrelocated_addr)
773 return kmap->ref_reloc_sym->addr -
774 kmap->ref_reloc_sym->unrelocated_addr;
778 static bool want_demangle(bool is_kernel_sym)
780 return is_kernel_sym ? symbol_conf.demangle_kernel : symbol_conf.demangle;
783 void __weak arch__sym_update(struct symbol *s __maybe_unused,
784 GElf_Sym *sym __maybe_unused) { }
786 int dso__load_sym(struct dso *dso, struct map *map,
787 struct symsrc *syms_ss, struct symsrc *runtime_ss,
788 symbol_filter_t filter, int kmodule)
790 struct kmap *kmap = dso->kernel ? map__kmap(map) : NULL;
791 struct map_groups *kmaps = kmap ? map__kmaps(map) : NULL;
792 struct map *curr_map = map;
793 struct dso *curr_dso = dso;
794 Elf_Data *symstrs, *secstrs;
801 Elf_Data *syms, *opddata = NULL;
803 Elf_Scn *sec, *sec_strndx;
806 bool remap_kernel = false, adjust_kernel_syms = false;
811 dso->symtab_type = syms_ss->type;
812 dso->is_64_bit = syms_ss->is_64_bit;
813 dso->rel = syms_ss->ehdr.e_type == ET_REL;
816 * Modules may already have symbols from kallsyms, but those symbols
817 * have the wrong values for the dso maps, so remove them.
819 if (kmodule && syms_ss->symtab)
820 symbols__delete(&dso->symbols[map->type]);
822 if (!syms_ss->symtab) {
824 * If the vmlinux is stripped, fail so we will fall back
825 * to using kallsyms. The vmlinux runtime symbols aren't
831 syms_ss->symtab = syms_ss->dynsym;
832 syms_ss->symshdr = syms_ss->dynshdr;
836 ehdr = syms_ss->ehdr;
837 sec = syms_ss->symtab;
838 shdr = syms_ss->symshdr;
840 if (elf_section_by_name(runtime_ss->elf, &runtime_ss->ehdr, &tshdr,
842 dso->text_offset = tshdr.sh_addr - tshdr.sh_offset;
844 if (runtime_ss->opdsec)
845 opddata = elf_rawdata(runtime_ss->opdsec, NULL);
847 syms = elf_getdata(sec, NULL);
851 sec = elf_getscn(elf, shdr.sh_link);
855 symstrs = elf_getdata(sec, NULL);
859 sec_strndx = elf_getscn(runtime_ss->elf, runtime_ss->ehdr.e_shstrndx);
860 if (sec_strndx == NULL)
863 secstrs = elf_getdata(sec_strndx, NULL);
867 nr_syms = shdr.sh_size / shdr.sh_entsize;
869 memset(&sym, 0, sizeof(sym));
872 * The kernel relocation symbol is needed in advance in order to adjust
873 * kernel maps correctly.
875 if (ref_reloc_sym_not_found(kmap)) {
876 elf_symtab__for_each_symbol(syms, nr_syms, idx, sym) {
877 const char *elf_name = elf_sym__name(&sym, symstrs);
879 if (strcmp(elf_name, kmap->ref_reloc_sym->name))
881 kmap->ref_reloc_sym->unrelocated_addr = sym.st_value;
882 map->reloc = kmap->ref_reloc_sym->addr -
883 kmap->ref_reloc_sym->unrelocated_addr;
889 * Handle any relocation of vdso necessary because older kernels
890 * attempted to prelink vdso to its virtual address.
892 if (dso__is_vdso(dso))
893 map->reloc = map->start - dso->text_offset;
895 dso->adjust_symbols = runtime_ss->adjust_symbols || ref_reloc(kmap);
897 * Initial kernel and module mappings do not map to the dso. For
898 * function mappings, flag the fixups.
900 if (map->type == MAP__FUNCTION && (dso->kernel || kmodule)) {
902 adjust_kernel_syms = dso->adjust_symbols;
904 elf_symtab__for_each_symbol(syms, nr_syms, idx, sym) {
906 const char *elf_name = elf_sym__name(&sym, symstrs);
907 char *demangled = NULL;
908 int is_label = elf_sym__is_label(&sym);
909 const char *section_name;
910 bool used_opd = false;
912 if (!is_label && !elf_sym__is_a(&sym, map->type))
915 /* Reject ARM ELF "mapping symbols": these aren't unique and
916 * don't identify functions, so will confuse the profile
918 if (ehdr.e_machine == EM_ARM || ehdr.e_machine == EM_AARCH64) {
919 if (elf_name[0] == '$' && strchr("adtx", elf_name[1])
920 && (elf_name[2] == '\0' || elf_name[2] == '.'))
924 if (runtime_ss->opdsec && sym.st_shndx == runtime_ss->opdidx) {
925 u32 offset = sym.st_value - syms_ss->opdshdr.sh_addr;
926 u64 *opd = opddata->d_buf + offset;
927 sym.st_value = DSO__SWAP(dso, u64, *opd);
928 sym.st_shndx = elf_addr_to_index(runtime_ss->elf,
933 * When loading symbols in a data mapping, ABS symbols (which
934 * has a value of SHN_ABS in its st_shndx) failed at
935 * elf_getscn(). And it marks the loading as a failure so
936 * already loaded symbols cannot be fixed up.
938 * I'm not sure what should be done. Just ignore them for now.
941 if (sym.st_shndx == SHN_ABS)
944 sec = elf_getscn(runtime_ss->elf, sym.st_shndx);
948 gelf_getshdr(sec, &shdr);
950 if (is_label && !elf_sec__is_a(&shdr, secstrs, map->type))
953 section_name = elf_sec__name(&shdr, secstrs);
955 /* On ARM, symbols for thumb functions have 1 added to
956 * the symbol address as a flag - remove it */
957 if ((ehdr.e_machine == EM_ARM) &&
958 (map->type == MAP__FUNCTION) &&
962 if (dso->kernel || kmodule) {
963 char dso_name[PATH_MAX];
965 /* Adjust symbol to map to file offset */
966 if (adjust_kernel_syms)
967 sym.st_value -= shdr.sh_addr - shdr.sh_offset;
969 if (strcmp(section_name,
970 (curr_dso->short_name +
971 dso->short_name_len)) == 0)
974 if (strcmp(section_name, ".text") == 0) {
976 * The initial kernel mapping is based on
977 * kallsyms and identity maps. Overwrite it to
978 * map to the kernel dso.
980 if (remap_kernel && dso->kernel) {
981 remap_kernel = false;
982 map->start = shdr.sh_addr +
984 map->end = map->start + shdr.sh_size;
985 map->pgoff = shdr.sh_offset;
986 map->map_ip = map__map_ip;
987 map->unmap_ip = map__unmap_ip;
988 /* Ensure maps are correctly ordered */
991 map_groups__remove(kmaps, map);
992 map_groups__insert(kmaps, map);
998 * The initial module mapping is based on
999 * /proc/modules mapped to offset zero.
1000 * Overwrite it to map to the module dso.
1002 if (remap_kernel && kmodule) {
1003 remap_kernel = false;
1004 map->pgoff = shdr.sh_offset;
1015 snprintf(dso_name, sizeof(dso_name),
1016 "%s%s", dso->short_name, section_name);
1018 curr_map = map_groups__find_by_name(kmaps, map->type, dso_name);
1019 if (curr_map == NULL) {
1020 u64 start = sym.st_value;
1023 start += map->start + shdr.sh_offset;
1025 curr_dso = dso__new(dso_name);
1026 if (curr_dso == NULL)
1028 curr_dso->kernel = dso->kernel;
1029 curr_dso->long_name = dso->long_name;
1030 curr_dso->long_name_len = dso->long_name_len;
1031 curr_map = map__new2(start, curr_dso,
1034 if (curr_map == NULL) {
1037 if (adjust_kernel_syms) {
1038 curr_map->start = shdr.sh_addr +
1040 curr_map->end = curr_map->start +
1042 curr_map->pgoff = shdr.sh_offset;
1044 curr_map->map_ip = identity__map_ip;
1045 curr_map->unmap_ip = identity__map_ip;
1047 curr_dso->symtab_type = dso->symtab_type;
1048 map_groups__insert(kmaps, curr_map);
1050 * Add it before we drop the referece to curr_map,
1051 * i.e. while we still are sure to have a reference
1052 * to this DSO via curr_map->dso.
1054 dsos__add(&map->groups->machine->dsos, curr_dso);
1055 /* kmaps already got it */
1057 dso__set_loaded(curr_dso, map->type);
1059 curr_dso = curr_map->dso;
1064 if ((used_opd && runtime_ss->adjust_symbols)
1065 || (!used_opd && syms_ss->adjust_symbols)) {
1066 pr_debug4("%s: adjusting symbol: st_value: %#" PRIx64 " "
1067 "sh_addr: %#" PRIx64 " sh_offset: %#" PRIx64 "\n", __func__,
1068 (u64)sym.st_value, (u64)shdr.sh_addr,
1069 (u64)shdr.sh_offset);
1070 sym.st_value -= shdr.sh_addr - shdr.sh_offset;
1074 * We need to figure out if the object was created from C++ sources
1075 * DWARF DW_compile_unit has this, but we don't always have access
1078 if (want_demangle(dso->kernel || kmodule)) {
1079 int demangle_flags = DMGL_NO_OPTS;
1081 demangle_flags = DMGL_PARAMS | DMGL_ANSI;
1083 demangled = bfd_demangle(NULL, elf_name, demangle_flags);
1084 if (demangled == NULL)
1085 demangled = java_demangle_sym(elf_name, JAVA_DEMANGLE_NORET);
1086 else if (rust_is_mangled(demangled))
1088 * Input to Rust demangling is the BFD-demangled
1089 * name which it Rust-demangles in place.
1091 rust_demangle_sym(demangled);
1093 if (demangled != NULL)
1094 elf_name = demangled;
1096 f = symbol__new(sym.st_value, sym.st_size,
1097 GELF_ST_BIND(sym.st_info), elf_name);
1102 arch__sym_update(f, &sym);
1104 if (filter && filter(curr_map, f))
1107 symbols__insert(&curr_dso->symbols[curr_map->type], f);
1113 * For misannotated, zeroed, ASM function sizes.
1116 if (!symbol_conf.allow_aliases)
1117 symbols__fixup_duplicate(&dso->symbols[map->type]);
1118 symbols__fixup_end(&dso->symbols[map->type]);
1121 * We need to fixup this here too because we create new
1122 * maps here, for things like vsyscall sections.
1124 __map_groups__fixup_end(kmaps, map->type);
1132 static int elf_read_maps(Elf *elf, bool exe, mapfn_t mapfn, void *data)
1139 if (elf_getphdrnum(elf, &phdrnum))
1142 for (i = 0; i < phdrnum; i++) {
1143 if (gelf_getphdr(elf, i, &phdr) == NULL)
1145 if (phdr.p_type != PT_LOAD)
1148 if (!(phdr.p_flags & PF_X))
1151 if (!(phdr.p_flags & PF_R))
1154 sz = min(phdr.p_memsz, phdr.p_filesz);
1157 err = mapfn(phdr.p_vaddr, sz, phdr.p_offset, data);
1164 int file__read_maps(int fd, bool exe, mapfn_t mapfn, void *data,
1170 elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL);
1175 *is_64_bit = (gelf_getclass(elf) == ELFCLASS64);
1177 err = elf_read_maps(elf, exe, mapfn, data);
1183 enum dso_type dso__type_fd(int fd)
1185 enum dso_type dso_type = DSO__TYPE_UNKNOWN;
1190 elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL);
1195 if (ek != ELF_K_ELF)
1198 if (gelf_getclass(elf) == ELFCLASS64) {
1199 dso_type = DSO__TYPE_64BIT;
1203 if (gelf_getehdr(elf, &ehdr) == NULL)
1206 if (ehdr.e_machine == EM_X86_64)
1207 dso_type = DSO__TYPE_X32BIT;
1209 dso_type = DSO__TYPE_32BIT;
1216 static int copy_bytes(int from, off_t from_offs, int to, off_t to_offs, u64 len)
1221 char *buf = malloc(page_size);
1226 if (lseek(to, to_offs, SEEK_SET) != to_offs)
1229 if (lseek(from, from_offs, SEEK_SET) != from_offs)
1236 /* Use read because mmap won't work on proc files */
1237 r = read(from, buf, n);
1243 r = write(to, buf, n);
1264 static int kcore__open(struct kcore *kcore, const char *filename)
1268 kcore->fd = open(filename, O_RDONLY);
1269 if (kcore->fd == -1)
1272 kcore->elf = elf_begin(kcore->fd, ELF_C_READ, NULL);
1276 kcore->elfclass = gelf_getclass(kcore->elf);
1277 if (kcore->elfclass == ELFCLASSNONE)
1280 ehdr = gelf_getehdr(kcore->elf, &kcore->ehdr);
1287 elf_end(kcore->elf);
1293 static int kcore__init(struct kcore *kcore, char *filename, int elfclass,
1296 kcore->elfclass = elfclass;
1299 kcore->fd = mkstemp(filename);
1301 kcore->fd = open(filename, O_WRONLY | O_CREAT | O_EXCL, 0400);
1302 if (kcore->fd == -1)
1305 kcore->elf = elf_begin(kcore->fd, ELF_C_WRITE, NULL);
1309 if (!gelf_newehdr(kcore->elf, elfclass))
1312 memset(&kcore->ehdr, 0, sizeof(GElf_Ehdr));
1317 elf_end(kcore->elf);
1324 static void kcore__close(struct kcore *kcore)
1326 elf_end(kcore->elf);
1330 static int kcore__copy_hdr(struct kcore *from, struct kcore *to, size_t count)
1332 GElf_Ehdr *ehdr = &to->ehdr;
1333 GElf_Ehdr *kehdr = &from->ehdr;
1335 memcpy(ehdr->e_ident, kehdr->e_ident, EI_NIDENT);
1336 ehdr->e_type = kehdr->e_type;
1337 ehdr->e_machine = kehdr->e_machine;
1338 ehdr->e_version = kehdr->e_version;
1341 ehdr->e_flags = kehdr->e_flags;
1342 ehdr->e_phnum = count;
1343 ehdr->e_shentsize = 0;
1345 ehdr->e_shstrndx = 0;
1347 if (from->elfclass == ELFCLASS32) {
1348 ehdr->e_phoff = sizeof(Elf32_Ehdr);
1349 ehdr->e_ehsize = sizeof(Elf32_Ehdr);
1350 ehdr->e_phentsize = sizeof(Elf32_Phdr);
1352 ehdr->e_phoff = sizeof(Elf64_Ehdr);
1353 ehdr->e_ehsize = sizeof(Elf64_Ehdr);
1354 ehdr->e_phentsize = sizeof(Elf64_Phdr);
1357 if (!gelf_update_ehdr(to->elf, ehdr))
1360 if (!gelf_newphdr(to->elf, count))
1366 static int kcore__add_phdr(struct kcore *kcore, int idx, off_t offset,
1371 .p_flags = PF_R | PF_W | PF_X,
1377 .p_align = page_size,
1380 if (!gelf_update_phdr(kcore->elf, idx, &phdr))
1386 static off_t kcore__write(struct kcore *kcore)
1388 return elf_update(kcore->elf, ELF_C_WRITE);
1397 struct kcore_copy_info {
1403 u64 last_module_symbol;
1404 struct phdr_data kernel_map;
1405 struct phdr_data modules_map;
1408 static int kcore_copy__process_kallsyms(void *arg, const char *name, char type,
1411 struct kcore_copy_info *kci = arg;
1413 if (!symbol_type__is_a(type, MAP__FUNCTION))
1416 if (strchr(name, '[')) {
1417 if (start > kci->last_module_symbol)
1418 kci->last_module_symbol = start;
1422 if (!kci->first_symbol || start < kci->first_symbol)
1423 kci->first_symbol = start;
1425 if (!kci->last_symbol || start > kci->last_symbol)
1426 kci->last_symbol = start;
1428 if (!strcmp(name, "_stext")) {
1433 if (!strcmp(name, "_etext")) {
1441 static int kcore_copy__parse_kallsyms(struct kcore_copy_info *kci,
1444 char kallsyms_filename[PATH_MAX];
1446 scnprintf(kallsyms_filename, PATH_MAX, "%s/kallsyms", dir);
1448 if (symbol__restricted_filename(kallsyms_filename, "/proc/kallsyms"))
1451 if (kallsyms__parse(kallsyms_filename, kci,
1452 kcore_copy__process_kallsyms) < 0)
1458 static int kcore_copy__process_modules(void *arg,
1459 const char *name __maybe_unused,
1462 struct kcore_copy_info *kci = arg;
1464 if (!kci->first_module || start < kci->first_module)
1465 kci->first_module = start;
1470 static int kcore_copy__parse_modules(struct kcore_copy_info *kci,
1473 char modules_filename[PATH_MAX];
1475 scnprintf(modules_filename, PATH_MAX, "%s/modules", dir);
1477 if (symbol__restricted_filename(modules_filename, "/proc/modules"))
1480 if (modules__parse(modules_filename, kci,
1481 kcore_copy__process_modules) < 0)
1487 static void kcore_copy__map(struct phdr_data *p, u64 start, u64 end, u64 pgoff,
1490 if (p->addr || s < start || s >= end)
1494 p->offset = (s - start) + pgoff;
1495 p->len = e < end ? e - s : end - s;
1498 static int kcore_copy__read_map(u64 start, u64 len, u64 pgoff, void *data)
1500 struct kcore_copy_info *kci = data;
1501 u64 end = start + len;
1503 kcore_copy__map(&kci->kernel_map, start, end, pgoff, kci->stext,
1506 kcore_copy__map(&kci->modules_map, start, end, pgoff, kci->first_module,
1507 kci->last_module_symbol);
1512 static int kcore_copy__read_maps(struct kcore_copy_info *kci, Elf *elf)
1514 if (elf_read_maps(elf, true, kcore_copy__read_map, kci) < 0)
1520 static int kcore_copy__calc_maps(struct kcore_copy_info *kci, const char *dir,
1523 if (kcore_copy__parse_kallsyms(kci, dir))
1526 if (kcore_copy__parse_modules(kci, dir))
1530 kci->stext = round_down(kci->stext, page_size);
1532 kci->stext = round_down(kci->first_symbol, page_size);
1535 kci->etext = round_up(kci->etext, page_size);
1536 } else if (kci->last_symbol) {
1537 kci->etext = round_up(kci->last_symbol, page_size);
1538 kci->etext += page_size;
1541 kci->first_module = round_down(kci->first_module, page_size);
1543 if (kci->last_module_symbol) {
1544 kci->last_module_symbol = round_up(kci->last_module_symbol,
1546 kci->last_module_symbol += page_size;
1549 if (!kci->stext || !kci->etext)
1552 if (kci->first_module && !kci->last_module_symbol)
1555 return kcore_copy__read_maps(kci, elf);
1558 static int kcore_copy__copy_file(const char *from_dir, const char *to_dir,
1561 char from_filename[PATH_MAX];
1562 char to_filename[PATH_MAX];
1564 scnprintf(from_filename, PATH_MAX, "%s/%s", from_dir, name);
1565 scnprintf(to_filename, PATH_MAX, "%s/%s", to_dir, name);
1567 return copyfile_mode(from_filename, to_filename, 0400);
1570 static int kcore_copy__unlink(const char *dir, const char *name)
1572 char filename[PATH_MAX];
1574 scnprintf(filename, PATH_MAX, "%s/%s", dir, name);
1576 return unlink(filename);
1579 static int kcore_copy__compare_fds(int from, int to)
1587 buf_from = malloc(page_size);
1588 buf_to = malloc(page_size);
1589 if (!buf_from || !buf_to)
1593 /* Use read because mmap won't work on proc files */
1594 ret = read(from, buf_from, page_size);
1603 if (readn(to, buf_to, len) != (int)len)
1606 if (memcmp(buf_from, buf_to, len))
1617 static int kcore_copy__compare_files(const char *from_filename,
1618 const char *to_filename)
1620 int from, to, err = -1;
1622 from = open(from_filename, O_RDONLY);
1626 to = open(to_filename, O_RDONLY);
1628 goto out_close_from;
1630 err = kcore_copy__compare_fds(from, to);
1638 static int kcore_copy__compare_file(const char *from_dir, const char *to_dir,
1641 char from_filename[PATH_MAX];
1642 char to_filename[PATH_MAX];
1644 scnprintf(from_filename, PATH_MAX, "%s/%s", from_dir, name);
1645 scnprintf(to_filename, PATH_MAX, "%s/%s", to_dir, name);
1647 return kcore_copy__compare_files(from_filename, to_filename);
1651 * kcore_copy - copy kallsyms, modules and kcore from one directory to another.
1652 * @from_dir: from directory
1653 * @to_dir: to directory
1655 * This function copies kallsyms, modules and kcore files from one directory to
1656 * another. kallsyms and modules are copied entirely. Only code segments are
1657 * copied from kcore. It is assumed that two segments suffice: one for the
1658 * kernel proper and one for all the modules. The code segments are determined
1659 * from kallsyms and modules files. The kernel map starts at _stext or the
1660 * lowest function symbol, and ends at _etext or the highest function symbol.
1661 * The module map starts at the lowest module address and ends at the highest
1662 * module symbol. Start addresses are rounded down to the nearest page. End
1663 * addresses are rounded up to the nearest page. An extra page is added to the
1664 * highest kernel symbol and highest module symbol to, hopefully, encompass that
1665 * symbol too. Because it contains only code sections, the resulting kcore is
1666 * unusual. One significant peculiarity is that the mapping (start -> pgoff)
1667 * is not the same for the kernel map and the modules map. That happens because
1668 * the data is copied adjacently whereas the original kcore has gaps. Finally,
1669 * kallsyms and modules files are compared with their copies to check that
1670 * modules have not been loaded or unloaded while the copies were taking place.
1672 * Return: %0 on success, %-1 on failure.
1674 int kcore_copy(const char *from_dir, const char *to_dir)
1677 struct kcore extract;
1679 int idx = 0, err = -1;
1680 off_t offset = page_size, sz, modules_offset = 0;
1681 struct kcore_copy_info kci = { .stext = 0, };
1682 char kcore_filename[PATH_MAX];
1683 char extract_filename[PATH_MAX];
1685 if (kcore_copy__copy_file(from_dir, to_dir, "kallsyms"))
1688 if (kcore_copy__copy_file(from_dir, to_dir, "modules"))
1689 goto out_unlink_kallsyms;
1691 scnprintf(kcore_filename, PATH_MAX, "%s/kcore", from_dir);
1692 scnprintf(extract_filename, PATH_MAX, "%s/kcore", to_dir);
1694 if (kcore__open(&kcore, kcore_filename))
1695 goto out_unlink_modules;
1697 if (kcore_copy__calc_maps(&kci, from_dir, kcore.elf))
1698 goto out_kcore_close;
1700 if (kcore__init(&extract, extract_filename, kcore.elfclass, false))
1701 goto out_kcore_close;
1703 if (!kci.modules_map.addr)
1706 if (kcore__copy_hdr(&kcore, &extract, count))
1707 goto out_extract_close;
1709 if (kcore__add_phdr(&extract, idx++, offset, kci.kernel_map.addr,
1710 kci.kernel_map.len))
1711 goto out_extract_close;
1713 if (kci.modules_map.addr) {
1714 modules_offset = offset + kci.kernel_map.len;
1715 if (kcore__add_phdr(&extract, idx, modules_offset,
1716 kci.modules_map.addr, kci.modules_map.len))
1717 goto out_extract_close;
1720 sz = kcore__write(&extract);
1721 if (sz < 0 || sz > offset)
1722 goto out_extract_close;
1724 if (copy_bytes(kcore.fd, kci.kernel_map.offset, extract.fd, offset,
1725 kci.kernel_map.len))
1726 goto out_extract_close;
1728 if (modules_offset && copy_bytes(kcore.fd, kci.modules_map.offset,
1729 extract.fd, modules_offset,
1730 kci.modules_map.len))
1731 goto out_extract_close;
1733 if (kcore_copy__compare_file(from_dir, to_dir, "modules"))
1734 goto out_extract_close;
1736 if (kcore_copy__compare_file(from_dir, to_dir, "kallsyms"))
1737 goto out_extract_close;
1742 kcore__close(&extract);
1744 unlink(extract_filename);
1746 kcore__close(&kcore);
1749 kcore_copy__unlink(to_dir, "modules");
1750 out_unlink_kallsyms:
1752 kcore_copy__unlink(to_dir, "kallsyms");
1757 int kcore_extract__create(struct kcore_extract *kce)
1760 struct kcore extract;
1762 int idx = 0, err = -1;
1763 off_t offset = page_size, sz;
1765 if (kcore__open(&kcore, kce->kcore_filename))
1768 strcpy(kce->extract_filename, PERF_KCORE_EXTRACT);
1769 if (kcore__init(&extract, kce->extract_filename, kcore.elfclass, true))
1770 goto out_kcore_close;
1772 if (kcore__copy_hdr(&kcore, &extract, count))
1773 goto out_extract_close;
1775 if (kcore__add_phdr(&extract, idx, offset, kce->addr, kce->len))
1776 goto out_extract_close;
1778 sz = kcore__write(&extract);
1779 if (sz < 0 || sz > offset)
1780 goto out_extract_close;
1782 if (copy_bytes(kcore.fd, kce->offs, extract.fd, offset, kce->len))
1783 goto out_extract_close;
1788 kcore__close(&extract);
1790 unlink(kce->extract_filename);
1792 kcore__close(&kcore);
1797 void kcore_extract__delete(struct kcore_extract *kce)
1799 unlink(kce->extract_filename);
1802 #ifdef HAVE_GELF_GETNOTE_SUPPORT
1804 * populate_sdt_note : Parse raw data and identify SDT note
1805 * @elf: elf of the opened file
1806 * @data: raw data of a section with description offset applied
1807 * @len: note description size
1808 * @type: type of the note
1809 * @sdt_notes: List to add the SDT note
1811 * Responsible for parsing the @data in section .note.stapsdt in @elf and
1812 * if its an SDT note, it appends to @sdt_notes list.
1814 static int populate_sdt_note(Elf **elf, const char *data, size_t len,
1815 struct list_head *sdt_notes)
1817 const char *provider, *name;
1818 struct sdt_note *tmp = NULL;
1820 GElf_Addr base_off = 0;
1825 Elf64_Addr a64[NR_ADDR];
1826 Elf32_Addr a32[NR_ADDR];
1830 .d_buf = &buf, .d_type = ELF_T_ADDR, .d_version = EV_CURRENT,
1831 .d_size = gelf_fsize((*elf), ELF_T_ADDR, NR_ADDR, EV_CURRENT),
1832 .d_off = 0, .d_align = 0
1835 .d_buf = (void *) data, .d_type = ELF_T_ADDR,
1836 .d_version = EV_CURRENT, .d_size = dst.d_size, .d_off = 0,
1840 tmp = (struct sdt_note *)calloc(1, sizeof(struct sdt_note));
1846 INIT_LIST_HEAD(&tmp->note_list);
1848 if (len < dst.d_size + 3)
1851 /* Translation from file representation to memory representation */
1852 if (gelf_xlatetom(*elf, &dst, &src,
1853 elf_getident(*elf, NULL)[EI_DATA]) == NULL) {
1854 pr_err("gelf_xlatetom : %s\n", elf_errmsg(-1));
1858 /* Populate the fields of sdt_note */
1859 provider = data + dst.d_size;
1861 name = (const char *)memchr(provider, '\0', data + len - provider);
1865 tmp->provider = strdup(provider);
1866 if (!tmp->provider) {
1870 tmp->name = strdup(name);
1876 if (gelf_getclass(*elf) == ELFCLASS32) {
1877 memcpy(&tmp->addr, &buf, 3 * sizeof(Elf32_Addr));
1880 memcpy(&tmp->addr, &buf, 3 * sizeof(Elf64_Addr));
1884 if (!gelf_getehdr(*elf, &ehdr)) {
1885 pr_debug("%s : cannot get elf header.\n", __func__);
1890 /* Adjust the prelink effect :
1891 * Find out the .stapsdt.base section.
1892 * This scn will help us to handle prelinking (if present).
1893 * Compare the retrieved file offset of the base section with the
1894 * base address in the description of the SDT note. If its different,
1895 * then accordingly, adjust the note location.
1897 if (elf_section_by_name(*elf, &ehdr, &shdr, SDT_BASE_SCN, NULL)) {
1898 base_off = shdr.sh_offset;
1901 tmp->addr.a32[0] = tmp->addr.a32[0] + base_off -
1904 tmp->addr.a64[0] = tmp->addr.a64[0] + base_off -
1909 list_add_tail(&tmp->note_list, sdt_notes);
1915 free(tmp->provider);
1923 * construct_sdt_notes_list : constructs a list of SDT notes
1924 * @elf : elf to look into
1925 * @sdt_notes : empty list_head
1927 * Scans the sections in 'elf' for the section
1928 * .note.stapsdt. It, then calls populate_sdt_note to find
1929 * out the SDT events and populates the 'sdt_notes'.
1931 static int construct_sdt_notes_list(Elf *elf, struct list_head *sdt_notes)
1934 Elf_Scn *scn = NULL;
1937 size_t shstrndx, next;
1939 size_t name_off, desc_off, offset;
1942 if (gelf_getehdr(elf, &ehdr) == NULL) {
1946 if (elf_getshdrstrndx(elf, &shstrndx) != 0) {
1951 /* Look for the required section */
1952 scn = elf_section_by_name(elf, &ehdr, &shdr, SDT_NOTE_SCN, NULL);
1958 if ((shdr.sh_type != SHT_NOTE) || (shdr.sh_flags & SHF_ALLOC)) {
1963 data = elf_getdata(scn, NULL);
1965 /* Get the SDT notes */
1966 for (offset = 0; (next = gelf_getnote(data, offset, &nhdr, &name_off,
1967 &desc_off)) > 0; offset = next) {
1968 if (nhdr.n_namesz == sizeof(SDT_NOTE_NAME) &&
1969 !memcmp(data->d_buf + name_off, SDT_NOTE_NAME,
1970 sizeof(SDT_NOTE_NAME))) {
1971 /* Check the type of the note */
1972 if (nhdr.n_type != SDT_NOTE_TYPE)
1975 ret = populate_sdt_note(&elf, ((data->d_buf) + desc_off),
1976 nhdr.n_descsz, sdt_notes);
1981 if (list_empty(sdt_notes))
1989 * get_sdt_note_list : Wrapper to construct a list of sdt notes
1990 * @head : empty list_head
1991 * @target : file to find SDT notes from
1993 * This opens the file, initializes
1994 * the ELF and then calls construct_sdt_notes_list.
1996 int get_sdt_note_list(struct list_head *head, const char *target)
2001 fd = open(target, O_RDONLY);
2005 elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL);
2010 ret = construct_sdt_notes_list(elf, head);
2018 * cleanup_sdt_note_list : free the sdt notes' list
2019 * @sdt_notes: sdt notes' list
2021 * Free up the SDT notes in @sdt_notes.
2022 * Returns the number of SDT notes free'd.
2024 int cleanup_sdt_note_list(struct list_head *sdt_notes)
2026 struct sdt_note *tmp, *pos;
2029 list_for_each_entry_safe(pos, tmp, sdt_notes, note_list) {
2030 list_del(&pos->note_list);
2032 free(pos->provider);
2040 * sdt_notes__get_count: Counts the number of sdt events
2041 * @start: list_head to sdt_notes list
2043 * Returns the number of SDT notes in a list
2045 int sdt_notes__get_count(struct list_head *start)
2047 struct sdt_note *sdt_ptr;
2050 list_for_each_entry(sdt_ptr, start, note_list)
2056 void symbol__elf_init(void)
2058 elf_version(EV_CURRENT);