11 #include <symbol/kallsyms.h>
15 #define EM_AARCH64 183 /* ARM 64 bit */
19 #ifdef HAVE_CPLUS_DEMANGLE_SUPPORT
20 extern char *cplus_demangle(const char *, int);
22 static inline char *bfd_demangle(void __maybe_unused
*v
, const char *c
, int i
)
24 return cplus_demangle(c
, i
);
28 static inline char *bfd_demangle(void __maybe_unused
*v
,
29 const char __maybe_unused
*c
,
35 #define PACKAGE 'perf'
40 #ifndef HAVE_ELF_GETPHDRNUM_SUPPORT
41 static int elf_getphdrnum(Elf
*elf
, size_t *dst
)
46 ehdr
= gelf_getehdr(elf
, &gehdr
);
56 #ifndef NT_GNU_BUILD_ID
57 #define NT_GNU_BUILD_ID 3
61 * elf_symtab__for_each_symbol - iterate thru all the symbols
63 * @syms: struct elf_symtab instance to iterate
65 * @sym: GElf_Sym iterator
67 #define elf_symtab__for_each_symbol(syms, nr_syms, idx, sym) \
68 for (idx = 0, gelf_getsym(syms, idx, &sym);\
70 idx++, gelf_getsym(syms, idx, &sym))
72 static inline uint8_t elf_sym__type(const GElf_Sym
*sym
)
74 return GELF_ST_TYPE(sym
->st_info
);
77 static inline int elf_sym__is_function(const GElf_Sym
*sym
)
79 return (elf_sym__type(sym
) == STT_FUNC
||
80 elf_sym__type(sym
) == STT_GNU_IFUNC
) &&
82 sym
->st_shndx
!= SHN_UNDEF
;
85 static inline bool elf_sym__is_object(const GElf_Sym
*sym
)
87 return elf_sym__type(sym
) == STT_OBJECT
&&
89 sym
->st_shndx
!= SHN_UNDEF
;
92 static inline int elf_sym__is_label(const GElf_Sym
*sym
)
94 return elf_sym__type(sym
) == STT_NOTYPE
&&
96 sym
->st_shndx
!= SHN_UNDEF
&&
97 sym
->st_shndx
!= SHN_ABS
;
100 static bool elf_sym__is_a(GElf_Sym
*sym
, enum map_type type
)
104 return elf_sym__is_function(sym
);
106 return elf_sym__is_object(sym
);
112 static inline const char *elf_sym__name(const GElf_Sym
*sym
,
113 const Elf_Data
*symstrs
)
115 return symstrs
->d_buf
+ sym
->st_name
;
118 static inline const char *elf_sec__name(const GElf_Shdr
*shdr
,
119 const Elf_Data
*secstrs
)
121 return secstrs
->d_buf
+ shdr
->sh_name
;
124 static inline int elf_sec__is_text(const GElf_Shdr
*shdr
,
125 const Elf_Data
*secstrs
)
127 return strstr(elf_sec__name(shdr
, secstrs
), "text") != NULL
;
130 static inline bool elf_sec__is_data(const GElf_Shdr
*shdr
,
131 const Elf_Data
*secstrs
)
133 return strstr(elf_sec__name(shdr
, secstrs
), "data") != NULL
;
136 static bool elf_sec__is_a(GElf_Shdr
*shdr
, Elf_Data
*secstrs
,
141 return elf_sec__is_text(shdr
, secstrs
);
143 return elf_sec__is_data(shdr
, secstrs
);
149 static size_t elf_addr_to_index(Elf
*elf
, GElf_Addr addr
)
155 while ((sec
= elf_nextscn(elf
, sec
)) != NULL
) {
156 gelf_getshdr(sec
, &shdr
);
158 if ((addr
>= shdr
.sh_addr
) &&
159 (addr
< (shdr
.sh_addr
+ shdr
.sh_size
)))
168 Elf_Scn
*elf_section_by_name(Elf
*elf
, GElf_Ehdr
*ep
,
169 GElf_Shdr
*shp
, const char *name
, size_t *idx
)
174 /* Elf is corrupted/truncated, avoid calling elf_strptr. */
175 if (!elf_rawdata(elf_getscn(elf
, ep
->e_shstrndx
), NULL
))
178 while ((sec
= elf_nextscn(elf
, sec
)) != NULL
) {
181 gelf_getshdr(sec
, shp
);
182 str
= elf_strptr(elf
, ep
->e_shstrndx
, shp
->sh_name
);
183 if (str
&& !strcmp(name
, str
)) {
194 #define elf_section__for_each_rel(reldata, pos, pos_mem, idx, nr_entries) \
195 for (idx = 0, pos = gelf_getrel(reldata, 0, &pos_mem); \
197 ++idx, pos = gelf_getrel(reldata, idx, &pos_mem))
199 #define elf_section__for_each_rela(reldata, pos, pos_mem, idx, nr_entries) \
200 for (idx = 0, pos = gelf_getrela(reldata, 0, &pos_mem); \
202 ++idx, pos = gelf_getrela(reldata, idx, &pos_mem))
205 * We need to check if we have a .dynsym, so that we can handle the
206 * .plt, synthesizing its symbols, that aren't on the symtabs (be it
207 * .dynsym or .symtab).
208 * And always look at the original dso, not at debuginfo packages, that
209 * have the PLT data stripped out (shdr_rel_plt.sh_type == SHT_NOBITS).
211 int dso__synthesize_plt_symbols(struct dso
*dso
, struct symsrc
*ss
, struct map
*map
,
212 symbol_filter_t filter
)
214 uint32_t nr_rel_entries
, idx
;
219 GElf_Shdr shdr_rel_plt
, shdr_dynsym
;
220 Elf_Data
*reldata
, *syms
, *symstrs
;
221 Elf_Scn
*scn_plt_rel
, *scn_symstrs
, *scn_dynsym
;
224 char sympltname
[1024];
226 int nr
= 0, symidx
, err
= 0;
234 scn_dynsym
= ss
->dynsym
;
235 shdr_dynsym
= ss
->dynshdr
;
236 dynsym_idx
= ss
->dynsym_idx
;
238 if (scn_dynsym
== NULL
)
241 scn_plt_rel
= elf_section_by_name(elf
, &ehdr
, &shdr_rel_plt
,
243 if (scn_plt_rel
== NULL
) {
244 scn_plt_rel
= elf_section_by_name(elf
, &ehdr
, &shdr_rel_plt
,
246 if (scn_plt_rel
== NULL
)
252 if (shdr_rel_plt
.sh_link
!= dynsym_idx
)
255 if (elf_section_by_name(elf
, &ehdr
, &shdr_plt
, ".plt", NULL
) == NULL
)
259 * Fetch the relocation section to find the idxes to the GOT
260 * and the symbols in the .dynsym they refer to.
262 reldata
= elf_getdata(scn_plt_rel
, NULL
);
266 syms
= elf_getdata(scn_dynsym
, NULL
);
270 scn_symstrs
= elf_getscn(elf
, shdr_dynsym
.sh_link
);
271 if (scn_symstrs
== NULL
)
274 symstrs
= elf_getdata(scn_symstrs
, NULL
);
278 if (symstrs
->d_size
== 0)
281 nr_rel_entries
= shdr_rel_plt
.sh_size
/ shdr_rel_plt
.sh_entsize
;
282 plt_offset
= shdr_plt
.sh_offset
;
284 if (shdr_rel_plt
.sh_type
== SHT_RELA
) {
285 GElf_Rela pos_mem
, *pos
;
287 elf_section__for_each_rela(reldata
, pos
, pos_mem
, idx
,
289 symidx
= GELF_R_SYM(pos
->r_info
);
290 plt_offset
+= shdr_plt
.sh_entsize
;
291 gelf_getsym(syms
, symidx
, &sym
);
292 snprintf(sympltname
, sizeof(sympltname
),
293 "%s@plt", elf_sym__name(&sym
, symstrs
));
295 f
= symbol__new(plt_offset
, shdr_plt
.sh_entsize
,
296 STB_GLOBAL
, sympltname
);
300 if (filter
&& filter(map
, f
))
303 symbols__insert(&dso
->symbols
[map
->type
], f
);
307 } else if (shdr_rel_plt
.sh_type
== SHT_REL
) {
308 GElf_Rel pos_mem
, *pos
;
309 elf_section__for_each_rel(reldata
, pos
, pos_mem
, idx
,
311 symidx
= GELF_R_SYM(pos
->r_info
);
312 plt_offset
+= shdr_plt
.sh_entsize
;
313 gelf_getsym(syms
, symidx
, &sym
);
314 snprintf(sympltname
, sizeof(sympltname
),
315 "%s@plt", elf_sym__name(&sym
, symstrs
));
317 f
= symbol__new(plt_offset
, shdr_plt
.sh_entsize
,
318 STB_GLOBAL
, sympltname
);
322 if (filter
&& filter(map
, f
))
325 symbols__insert(&dso
->symbols
[map
->type
], f
);
335 pr_debug("%s: problems reading %s PLT info.\n",
336 __func__
, dso
->long_name
);
341 * Align offset to 4 bytes as needed for note name and descriptor data.
343 #define NOTE_ALIGN(n) (((n) + 3) & -4U)
345 static int elf_read_build_id(Elf
*elf
, void *bf
, size_t size
)
355 if (size
< BUILD_ID_SIZE
)
362 if (gelf_getehdr(elf
, &ehdr
) == NULL
) {
363 pr_err("%s: cannot get elf header.\n", __func__
);
368 * Check following sections for notes:
369 * '.note.gnu.build-id'
371 * '.note' (VDSO specific)
374 sec
= elf_section_by_name(elf
, &ehdr
, &shdr
,
375 ".note.gnu.build-id", NULL
);
379 sec
= elf_section_by_name(elf
, &ehdr
, &shdr
,
384 sec
= elf_section_by_name(elf
, &ehdr
, &shdr
,
393 data
= elf_getdata(sec
, NULL
);
398 while (ptr
< (data
->d_buf
+ data
->d_size
)) {
399 GElf_Nhdr
*nhdr
= ptr
;
400 size_t namesz
= NOTE_ALIGN(nhdr
->n_namesz
),
401 descsz
= NOTE_ALIGN(nhdr
->n_descsz
);
404 ptr
+= sizeof(*nhdr
);
407 if (nhdr
->n_type
== NT_GNU_BUILD_ID
&&
408 nhdr
->n_namesz
== sizeof("GNU")) {
409 if (memcmp(name
, "GNU", sizeof("GNU")) == 0) {
410 size_t sz
= min(size
, descsz
);
412 memset(bf
+ sz
, 0, size
- sz
);
424 int filename__read_build_id(const char *filename
, void *bf
, size_t size
)
429 if (size
< BUILD_ID_SIZE
)
432 fd
= open(filename
, O_RDONLY
);
436 elf
= elf_begin(fd
, PERF_ELF_C_READ_MMAP
, NULL
);
438 pr_debug2("%s: cannot read %s ELF file.\n", __func__
, filename
);
442 err
= elf_read_build_id(elf
, bf
, size
);
451 int sysfs__read_build_id(const char *filename
, void *build_id
, size_t size
)
455 if (size
< BUILD_ID_SIZE
)
458 fd
= open(filename
, O_RDONLY
);
465 size_t namesz
, descsz
;
467 if (read(fd
, &nhdr
, sizeof(nhdr
)) != sizeof(nhdr
))
470 namesz
= NOTE_ALIGN(nhdr
.n_namesz
);
471 descsz
= NOTE_ALIGN(nhdr
.n_descsz
);
472 if (nhdr
.n_type
== NT_GNU_BUILD_ID
&&
473 nhdr
.n_namesz
== sizeof("GNU")) {
474 if (read(fd
, bf
, namesz
) != (ssize_t
)namesz
)
476 if (memcmp(bf
, "GNU", sizeof("GNU")) == 0) {
477 size_t sz
= min(descsz
, size
);
478 if (read(fd
, build_id
, sz
) == (ssize_t
)sz
) {
479 memset(build_id
+ sz
, 0, size
- sz
);
483 } else if (read(fd
, bf
, descsz
) != (ssize_t
)descsz
)
486 int n
= namesz
+ descsz
;
487 if (read(fd
, bf
, n
) != n
)
496 int filename__read_debuglink(const char *filename
, char *debuglink
,
507 fd
= open(filename
, O_RDONLY
);
511 elf
= elf_begin(fd
, PERF_ELF_C_READ_MMAP
, NULL
);
513 pr_debug2("%s: cannot read %s ELF file.\n", __func__
, filename
);
521 if (gelf_getehdr(elf
, &ehdr
) == NULL
) {
522 pr_err("%s: cannot get elf header.\n", __func__
);
526 sec
= elf_section_by_name(elf
, &ehdr
, &shdr
,
527 ".gnu_debuglink", NULL
);
531 data
= elf_getdata(sec
, NULL
);
535 /* the start of this section is a zero-terminated string */
536 strncpy(debuglink
, data
->d_buf
, size
);
548 static int dso__swap_init(struct dso
*dso
, unsigned char eidata
)
550 static unsigned int const endian
= 1;
552 dso
->needs_swap
= DSO_SWAP__NO
;
556 /* We are big endian, DSO is little endian. */
557 if (*(unsigned char const *)&endian
!= 1)
558 dso
->needs_swap
= DSO_SWAP__YES
;
562 /* We are little endian, DSO is big endian. */
563 if (*(unsigned char const *)&endian
!= 0)
564 dso
->needs_swap
= DSO_SWAP__YES
;
568 pr_err("unrecognized DSO data encoding %d\n", eidata
);
575 static int decompress_kmodule(struct dso
*dso
, const char *name
,
576 enum dso_binary_type type
)
579 const char *ext
= strrchr(name
, '.');
580 char tmpbuf
[] = "/tmp/perf-kmod-XXXXXX";
582 if (type
!= DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP
&&
583 type
!= DSO_BINARY_TYPE__GUEST_KMODULE_COMP
&&
584 type
!= DSO_BINARY_TYPE__BUILD_ID_CACHE
)
587 if (!ext
|| !is_supported_compression(ext
+ 1)) {
588 ext
= strrchr(dso
->name
, '.');
589 if (!ext
|| !is_supported_compression(ext
+ 1))
593 fd
= mkstemp(tmpbuf
);
597 if (!decompress_to_file(ext
+ 1, name
, fd
)) {
607 bool symsrc__possibly_runtime(struct symsrc
*ss
)
609 return ss
->dynsym
|| ss
->opdsec
;
612 bool symsrc__has_symtab(struct symsrc
*ss
)
614 return ss
->symtab
!= NULL
;
617 void symsrc__destroy(struct symsrc
*ss
)
624 int symsrc__init(struct symsrc
*ss
, struct dso
*dso
, const char *name
,
625 enum dso_binary_type type
)
632 if (dso__needs_decompress(dso
))
633 fd
= decompress_kmodule(dso
, name
, type
);
635 fd
= open(name
, O_RDONLY
);
640 elf
= elf_begin(fd
, PERF_ELF_C_READ_MMAP
, NULL
);
642 pr_debug("%s: cannot read %s ELF file.\n", __func__
, name
);
646 if (gelf_getehdr(elf
, &ehdr
) == NULL
) {
647 pr_debug("%s: cannot get elf header.\n", __func__
);
651 if (dso__swap_init(dso
, ehdr
.e_ident
[EI_DATA
]))
654 /* Always reject images with a mismatched build-id: */
655 if (dso
->has_build_id
) {
656 u8 build_id
[BUILD_ID_SIZE
];
658 if (elf_read_build_id(elf
, build_id
, BUILD_ID_SIZE
) < 0)
661 if (!dso__build_id_equal(dso
, build_id
))
665 ss
->is_64_bit
= (gelf_getclass(elf
) == ELFCLASS64
);
667 ss
->symtab
= elf_section_by_name(elf
, &ehdr
, &ss
->symshdr
, ".symtab",
669 if (ss
->symshdr
.sh_type
!= SHT_SYMTAB
)
673 ss
->dynsym
= elf_section_by_name(elf
, &ehdr
, &ss
->dynshdr
, ".dynsym",
675 if (ss
->dynshdr
.sh_type
!= SHT_DYNSYM
)
679 ss
->opdsec
= elf_section_by_name(elf
, &ehdr
, &ss
->opdshdr
, ".opd",
681 if (ss
->opdshdr
.sh_type
!= SHT_PROGBITS
)
684 if (dso
->kernel
== DSO_TYPE_USER
) {
686 ss
->adjust_symbols
= (ehdr
.e_type
== ET_EXEC
||
687 ehdr
.e_type
== ET_REL
||
689 elf_section_by_name(elf
, &ehdr
, &shdr
,
693 ss
->adjust_symbols
= ehdr
.e_type
== ET_EXEC
||
694 ehdr
.e_type
== ET_REL
;
697 ss
->name
= strdup(name
);
716 * ref_reloc_sym_not_found - has kernel relocation symbol been found.
717 * @kmap: kernel maps and relocation reference symbol
719 * This function returns %true if we are dealing with the kernel maps and the
720 * relocation reference symbol has not yet been found. Otherwise %false is
723 static bool ref_reloc_sym_not_found(struct kmap
*kmap
)
725 return kmap
&& kmap
->ref_reloc_sym
&& kmap
->ref_reloc_sym
->name
&&
726 !kmap
->ref_reloc_sym
->unrelocated_addr
;
730 * ref_reloc - kernel relocation offset.
731 * @kmap: kernel maps and relocation reference symbol
733 * This function returns the offset of kernel addresses as determined by using
734 * the relocation reference symbol i.e. if the kernel has not been relocated
735 * then the return value is zero.
737 static u64
ref_reloc(struct kmap
*kmap
)
739 if (kmap
&& kmap
->ref_reloc_sym
&&
740 kmap
->ref_reloc_sym
->unrelocated_addr
)
741 return kmap
->ref_reloc_sym
->addr
-
742 kmap
->ref_reloc_sym
->unrelocated_addr
;
746 static bool want_demangle(bool is_kernel_sym
)
748 return is_kernel_sym
? symbol_conf
.demangle_kernel
: symbol_conf
.demangle
;
751 int dso__load_sym(struct dso
*dso
, struct map
*map
,
752 struct symsrc
*syms_ss
, struct symsrc
*runtime_ss
,
753 symbol_filter_t filter
, int kmodule
)
755 struct kmap
*kmap
= dso
->kernel
? map__kmap(map
) : NULL
;
756 struct map
*curr_map
= map
;
757 struct dso
*curr_dso
= dso
;
758 Elf_Data
*symstrs
, *secstrs
;
764 Elf_Data
*syms
, *opddata
= NULL
;
766 Elf_Scn
*sec
, *sec_strndx
;
769 bool remap_kernel
= false, adjust_kernel_syms
= false;
771 dso
->symtab_type
= syms_ss
->type
;
772 dso
->is_64_bit
= syms_ss
->is_64_bit
;
773 dso
->rel
= syms_ss
->ehdr
.e_type
== ET_REL
;
776 * Modules may already have symbols from kallsyms, but those symbols
777 * have the wrong values for the dso maps, so remove them.
779 if (kmodule
&& syms_ss
->symtab
)
780 symbols__delete(&dso
->symbols
[map
->type
]);
782 if (!syms_ss
->symtab
) {
784 * If the vmlinux is stripped, fail so we will fall back
785 * to using kallsyms. The vmlinux runtime symbols aren't
791 syms_ss
->symtab
= syms_ss
->dynsym
;
792 syms_ss
->symshdr
= syms_ss
->dynshdr
;
796 ehdr
= syms_ss
->ehdr
;
797 sec
= syms_ss
->symtab
;
798 shdr
= syms_ss
->symshdr
;
800 if (runtime_ss
->opdsec
)
801 opddata
= elf_rawdata(runtime_ss
->opdsec
, NULL
);
803 syms
= elf_getdata(sec
, NULL
);
807 sec
= elf_getscn(elf
, shdr
.sh_link
);
811 symstrs
= elf_getdata(sec
, NULL
);
815 sec_strndx
= elf_getscn(runtime_ss
->elf
, runtime_ss
->ehdr
.e_shstrndx
);
816 if (sec_strndx
== NULL
)
819 secstrs
= elf_getdata(sec_strndx
, NULL
);
823 nr_syms
= shdr
.sh_size
/ shdr
.sh_entsize
;
825 memset(&sym
, 0, sizeof(sym
));
828 * The kernel relocation symbol is needed in advance in order to adjust
829 * kernel maps correctly.
831 if (ref_reloc_sym_not_found(kmap
)) {
832 elf_symtab__for_each_symbol(syms
, nr_syms
, idx
, sym
) {
833 const char *elf_name
= elf_sym__name(&sym
, symstrs
);
835 if (strcmp(elf_name
, kmap
->ref_reloc_sym
->name
))
837 kmap
->ref_reloc_sym
->unrelocated_addr
= sym
.st_value
;
838 map
->reloc
= kmap
->ref_reloc_sym
->addr
-
839 kmap
->ref_reloc_sym
->unrelocated_addr
;
844 dso
->adjust_symbols
= runtime_ss
->adjust_symbols
|| ref_reloc(kmap
);
846 * Initial kernel and module mappings do not map to the dso. For
847 * function mappings, flag the fixups.
849 if (map
->type
== MAP__FUNCTION
&& (dso
->kernel
|| kmodule
)) {
851 adjust_kernel_syms
= dso
->adjust_symbols
;
853 elf_symtab__for_each_symbol(syms
, nr_syms
, idx
, sym
) {
855 const char *elf_name
= elf_sym__name(&sym
, symstrs
);
856 char *demangled
= NULL
;
857 int is_label
= elf_sym__is_label(&sym
);
858 const char *section_name
;
859 bool used_opd
= false;
861 if (!is_label
&& !elf_sym__is_a(&sym
, map
->type
))
864 /* Reject ARM ELF "mapping symbols": these aren't unique and
865 * don't identify functions, so will confuse the profile
867 if (ehdr
.e_machine
== EM_ARM
) {
868 if (!strcmp(elf_name
, "$a") ||
869 !strcmp(elf_name
, "$d") ||
870 !strcmp(elf_name
, "$t"))
874 if (runtime_ss
->opdsec
&& sym
.st_shndx
== runtime_ss
->opdidx
) {
875 u32 offset
= sym
.st_value
- syms_ss
->opdshdr
.sh_addr
;
876 u64
*opd
= opddata
->d_buf
+ offset
;
877 sym
.st_value
= DSO__SWAP(dso
, u64
, *opd
);
878 sym
.st_shndx
= elf_addr_to_index(runtime_ss
->elf
,
883 * When loading symbols in a data mapping, ABS symbols (which
884 * has a value of SHN_ABS in its st_shndx) failed at
885 * elf_getscn(). And it marks the loading as a failure so
886 * already loaded symbols cannot be fixed up.
888 * I'm not sure what should be done. Just ignore them for now.
891 if (sym
.st_shndx
== SHN_ABS
)
894 sec
= elf_getscn(runtime_ss
->elf
, sym
.st_shndx
);
898 gelf_getshdr(sec
, &shdr
);
900 if (is_label
&& !elf_sec__is_a(&shdr
, secstrs
, map
->type
))
903 section_name
= elf_sec__name(&shdr
, secstrs
);
905 /* On ARM, symbols for thumb functions have 1 added to
906 * the symbol address as a flag - remove it */
907 if ((ehdr
.e_machine
== EM_ARM
) &&
908 (map
->type
== MAP__FUNCTION
) &&
912 if (dso
->kernel
|| kmodule
) {
913 char dso_name
[PATH_MAX
];
915 /* Adjust symbol to map to file offset */
916 if (adjust_kernel_syms
)
917 sym
.st_value
-= shdr
.sh_addr
- shdr
.sh_offset
;
919 if (strcmp(section_name
,
920 (curr_dso
->short_name
+
921 dso
->short_name_len
)) == 0)
924 if (strcmp(section_name
, ".text") == 0) {
926 * The initial kernel mapping is based on
927 * kallsyms and identity maps. Overwrite it to
928 * map to the kernel dso.
930 if (remap_kernel
&& dso
->kernel
) {
931 remap_kernel
= false;
932 map
->start
= shdr
.sh_addr
+
934 map
->end
= map
->start
+ shdr
.sh_size
;
935 map
->pgoff
= shdr
.sh_offset
;
936 map
->map_ip
= map__map_ip
;
937 map
->unmap_ip
= map__unmap_ip
;
938 /* Ensure maps are correctly ordered */
939 map_groups__remove(kmap
->kmaps
, map
);
940 map_groups__insert(kmap
->kmaps
, map
);
944 * The initial module mapping is based on
945 * /proc/modules mapped to offset zero.
946 * Overwrite it to map to the module dso.
948 if (remap_kernel
&& kmodule
) {
949 remap_kernel
= false;
950 map
->pgoff
= shdr
.sh_offset
;
961 snprintf(dso_name
, sizeof(dso_name
),
962 "%s%s", dso
->short_name
, section_name
);
964 curr_map
= map_groups__find_by_name(kmap
->kmaps
, map
->type
, dso_name
);
965 if (curr_map
== NULL
) {
966 u64 start
= sym
.st_value
;
969 start
+= map
->start
+ shdr
.sh_offset
;
971 curr_dso
= dso__new(dso_name
);
972 if (curr_dso
== NULL
)
974 curr_dso
->kernel
= dso
->kernel
;
975 curr_dso
->long_name
= dso
->long_name
;
976 curr_dso
->long_name_len
= dso
->long_name_len
;
977 curr_map
= map__new2(start
, curr_dso
,
979 if (curr_map
== NULL
) {
980 dso__delete(curr_dso
);
983 if (adjust_kernel_syms
) {
984 curr_map
->start
= shdr
.sh_addr
+
986 curr_map
->end
= curr_map
->start
+
988 curr_map
->pgoff
= shdr
.sh_offset
;
990 curr_map
->map_ip
= identity__map_ip
;
991 curr_map
->unmap_ip
= identity__map_ip
;
993 curr_dso
->symtab_type
= dso
->symtab_type
;
994 map_groups__insert(kmap
->kmaps
, curr_map
);
996 * The new DSO should go to the kernel DSOS
998 dsos__add(&map
->groups
->machine
->kernel_dsos
,
1000 dso__set_loaded(curr_dso
, map
->type
);
1002 curr_dso
= curr_map
->dso
;
1007 if ((used_opd
&& runtime_ss
->adjust_symbols
)
1008 || (!used_opd
&& syms_ss
->adjust_symbols
)) {
1009 pr_debug4("%s: adjusting symbol: st_value: %#" PRIx64
" "
1010 "sh_addr: %#" PRIx64
" sh_offset: %#" PRIx64
"\n", __func__
,
1011 (u64
)sym
.st_value
, (u64
)shdr
.sh_addr
,
1012 (u64
)shdr
.sh_offset
);
1013 sym
.st_value
-= shdr
.sh_addr
- shdr
.sh_offset
;
1017 * We need to figure out if the object was created from C++ sources
1018 * DWARF DW_compile_unit has this, but we don't always have access
1021 if (want_demangle(dso
->kernel
|| kmodule
)) {
1022 int demangle_flags
= DMGL_NO_OPTS
;
1024 demangle_flags
= DMGL_PARAMS
| DMGL_ANSI
;
1026 demangled
= bfd_demangle(NULL
, elf_name
, demangle_flags
);
1027 if (demangled
!= NULL
)
1028 elf_name
= demangled
;
1030 f
= symbol__new(sym
.st_value
, sym
.st_size
,
1031 GELF_ST_BIND(sym
.st_info
), elf_name
);
1036 if (filter
&& filter(curr_map
, f
))
1039 symbols__insert(&curr_dso
->symbols
[curr_map
->type
], f
);
1045 * For misannotated, zeroed, ASM function sizes.
1048 symbols__fixup_duplicate(&dso
->symbols
[map
->type
]);
1049 symbols__fixup_end(&dso
->symbols
[map
->type
]);
1052 * We need to fixup this here too because we create new
1053 * maps here, for things like vsyscall sections.
1055 __map_groups__fixup_end(kmap
->kmaps
, map
->type
);
1063 static int elf_read_maps(Elf
*elf
, bool exe
, mapfn_t mapfn
, void *data
)
1070 if (elf_getphdrnum(elf
, &phdrnum
))
1073 for (i
= 0; i
< phdrnum
; i
++) {
1074 if (gelf_getphdr(elf
, i
, &phdr
) == NULL
)
1076 if (phdr
.p_type
!= PT_LOAD
)
1079 if (!(phdr
.p_flags
& PF_X
))
1082 if (!(phdr
.p_flags
& PF_R
))
1085 sz
= min(phdr
.p_memsz
, phdr
.p_filesz
);
1088 err
= mapfn(phdr
.p_vaddr
, sz
, phdr
.p_offset
, data
);
1095 int file__read_maps(int fd
, bool exe
, mapfn_t mapfn
, void *data
,
1101 elf
= elf_begin(fd
, PERF_ELF_C_READ_MMAP
, NULL
);
1106 *is_64_bit
= (gelf_getclass(elf
) == ELFCLASS64
);
1108 err
= elf_read_maps(elf
, exe
, mapfn
, data
);
1114 enum dso_type
dso__type_fd(int fd
)
1116 enum dso_type dso_type
= DSO__TYPE_UNKNOWN
;
1121 elf
= elf_begin(fd
, PERF_ELF_C_READ_MMAP
, NULL
);
1126 if (ek
!= ELF_K_ELF
)
1129 if (gelf_getclass(elf
) == ELFCLASS64
) {
1130 dso_type
= DSO__TYPE_64BIT
;
1134 if (gelf_getehdr(elf
, &ehdr
) == NULL
)
1137 if (ehdr
.e_machine
== EM_X86_64
)
1138 dso_type
= DSO__TYPE_X32BIT
;
1140 dso_type
= DSO__TYPE_32BIT
;
1147 static int copy_bytes(int from
, off_t from_offs
, int to
, off_t to_offs
, u64 len
)
1152 char *buf
= malloc(page_size
);
1157 if (lseek(to
, to_offs
, SEEK_SET
) != to_offs
)
1160 if (lseek(from
, from_offs
, SEEK_SET
) != from_offs
)
1167 /* Use read because mmap won't work on proc files */
1168 r
= read(from
, buf
, n
);
1174 r
= write(to
, buf
, n
);
1195 static int kcore__open(struct kcore
*kcore
, const char *filename
)
1199 kcore
->fd
= open(filename
, O_RDONLY
);
1200 if (kcore
->fd
== -1)
1203 kcore
->elf
= elf_begin(kcore
->fd
, ELF_C_READ
, NULL
);
1207 kcore
->elfclass
= gelf_getclass(kcore
->elf
);
1208 if (kcore
->elfclass
== ELFCLASSNONE
)
1211 ehdr
= gelf_getehdr(kcore
->elf
, &kcore
->ehdr
);
1218 elf_end(kcore
->elf
);
1224 static int kcore__init(struct kcore
*kcore
, char *filename
, int elfclass
,
1229 kcore
->elfclass
= elfclass
;
1232 kcore
->fd
= mkstemp(filename
);
1234 kcore
->fd
= open(filename
, O_WRONLY
| O_CREAT
| O_EXCL
, 0400);
1235 if (kcore
->fd
== -1)
1238 kcore
->elf
= elf_begin(kcore
->fd
, ELF_C_WRITE
, NULL
);
1242 if (!gelf_newehdr(kcore
->elf
, elfclass
))
1245 ehdr
= gelf_getehdr(kcore
->elf
, &kcore
->ehdr
);
1252 elf_end(kcore
->elf
);
1259 static void kcore__close(struct kcore
*kcore
)
1261 elf_end(kcore
->elf
);
1265 static int kcore__copy_hdr(struct kcore
*from
, struct kcore
*to
, size_t count
)
1267 GElf_Ehdr
*ehdr
= &to
->ehdr
;
1268 GElf_Ehdr
*kehdr
= &from
->ehdr
;
1270 memcpy(ehdr
->e_ident
, kehdr
->e_ident
, EI_NIDENT
);
1271 ehdr
->e_type
= kehdr
->e_type
;
1272 ehdr
->e_machine
= kehdr
->e_machine
;
1273 ehdr
->e_version
= kehdr
->e_version
;
1276 ehdr
->e_flags
= kehdr
->e_flags
;
1277 ehdr
->e_phnum
= count
;
1278 ehdr
->e_shentsize
= 0;
1280 ehdr
->e_shstrndx
= 0;
1282 if (from
->elfclass
== ELFCLASS32
) {
1283 ehdr
->e_phoff
= sizeof(Elf32_Ehdr
);
1284 ehdr
->e_ehsize
= sizeof(Elf32_Ehdr
);
1285 ehdr
->e_phentsize
= sizeof(Elf32_Phdr
);
1287 ehdr
->e_phoff
= sizeof(Elf64_Ehdr
);
1288 ehdr
->e_ehsize
= sizeof(Elf64_Ehdr
);
1289 ehdr
->e_phentsize
= sizeof(Elf64_Phdr
);
1292 if (!gelf_update_ehdr(to
->elf
, ehdr
))
1295 if (!gelf_newphdr(to
->elf
, count
))
1301 static int kcore__add_phdr(struct kcore
*kcore
, int idx
, off_t offset
,
1307 phdr
= gelf_getphdr(kcore
->elf
, idx
, &gphdr
);
1311 phdr
->p_type
= PT_LOAD
;
1312 phdr
->p_flags
= PF_R
| PF_W
| PF_X
;
1313 phdr
->p_offset
= offset
;
1314 phdr
->p_vaddr
= addr
;
1316 phdr
->p_filesz
= len
;
1317 phdr
->p_memsz
= len
;
1318 phdr
->p_align
= page_size
;
1320 if (!gelf_update_phdr(kcore
->elf
, idx
, phdr
))
1326 static off_t
kcore__write(struct kcore
*kcore
)
1328 return elf_update(kcore
->elf
, ELF_C_WRITE
);
1337 struct kcore_copy_info
{
1343 u64 last_module_symbol
;
1344 struct phdr_data kernel_map
;
1345 struct phdr_data modules_map
;
1348 static int kcore_copy__process_kallsyms(void *arg
, const char *name
, char type
,
1351 struct kcore_copy_info
*kci
= arg
;
1353 if (!symbol_type__is_a(type
, MAP__FUNCTION
))
1356 if (strchr(name
, '[')) {
1357 if (start
> kci
->last_module_symbol
)
1358 kci
->last_module_symbol
= start
;
1362 if (!kci
->first_symbol
|| start
< kci
->first_symbol
)
1363 kci
->first_symbol
= start
;
1365 if (!kci
->last_symbol
|| start
> kci
->last_symbol
)
1366 kci
->last_symbol
= start
;
1368 if (!strcmp(name
, "_stext")) {
1373 if (!strcmp(name
, "_etext")) {
1381 static int kcore_copy__parse_kallsyms(struct kcore_copy_info
*kci
,
1384 char kallsyms_filename
[PATH_MAX
];
1386 scnprintf(kallsyms_filename
, PATH_MAX
, "%s/kallsyms", dir
);
1388 if (symbol__restricted_filename(kallsyms_filename
, "/proc/kallsyms"))
1391 if (kallsyms__parse(kallsyms_filename
, kci
,
1392 kcore_copy__process_kallsyms
) < 0)
1398 static int kcore_copy__process_modules(void *arg
,
1399 const char *name __maybe_unused
,
1402 struct kcore_copy_info
*kci
= arg
;
1404 if (!kci
->first_module
|| start
< kci
->first_module
)
1405 kci
->first_module
= start
;
1410 static int kcore_copy__parse_modules(struct kcore_copy_info
*kci
,
1413 char modules_filename
[PATH_MAX
];
1415 scnprintf(modules_filename
, PATH_MAX
, "%s/modules", dir
);
1417 if (symbol__restricted_filename(modules_filename
, "/proc/modules"))
1420 if (modules__parse(modules_filename
, kci
,
1421 kcore_copy__process_modules
) < 0)
1427 static void kcore_copy__map(struct phdr_data
*p
, u64 start
, u64 end
, u64 pgoff
,
1430 if (p
->addr
|| s
< start
|| s
>= end
)
1434 p
->offset
= (s
- start
) + pgoff
;
1435 p
->len
= e
< end
? e
- s
: end
- s
;
1438 static int kcore_copy__read_map(u64 start
, u64 len
, u64 pgoff
, void *data
)
1440 struct kcore_copy_info
*kci
= data
;
1441 u64 end
= start
+ len
;
1443 kcore_copy__map(&kci
->kernel_map
, start
, end
, pgoff
, kci
->stext
,
1446 kcore_copy__map(&kci
->modules_map
, start
, end
, pgoff
, kci
->first_module
,
1447 kci
->last_module_symbol
);
1452 static int kcore_copy__read_maps(struct kcore_copy_info
*kci
, Elf
*elf
)
1454 if (elf_read_maps(elf
, true, kcore_copy__read_map
, kci
) < 0)
1460 static int kcore_copy__calc_maps(struct kcore_copy_info
*kci
, const char *dir
,
1463 if (kcore_copy__parse_kallsyms(kci
, dir
))
1466 if (kcore_copy__parse_modules(kci
, dir
))
1470 kci
->stext
= round_down(kci
->stext
, page_size
);
1472 kci
->stext
= round_down(kci
->first_symbol
, page_size
);
1475 kci
->etext
= round_up(kci
->etext
, page_size
);
1476 } else if (kci
->last_symbol
) {
1477 kci
->etext
= round_up(kci
->last_symbol
, page_size
);
1478 kci
->etext
+= page_size
;
1481 kci
->first_module
= round_down(kci
->first_module
, page_size
);
1483 if (kci
->last_module_symbol
) {
1484 kci
->last_module_symbol
= round_up(kci
->last_module_symbol
,
1486 kci
->last_module_symbol
+= page_size
;
1489 if (!kci
->stext
|| !kci
->etext
)
1492 if (kci
->first_module
&& !kci
->last_module_symbol
)
1495 return kcore_copy__read_maps(kci
, elf
);
1498 static int kcore_copy__copy_file(const char *from_dir
, const char *to_dir
,
1501 char from_filename
[PATH_MAX
];
1502 char to_filename
[PATH_MAX
];
1504 scnprintf(from_filename
, PATH_MAX
, "%s/%s", from_dir
, name
);
1505 scnprintf(to_filename
, PATH_MAX
, "%s/%s", to_dir
, name
);
1507 return copyfile_mode(from_filename
, to_filename
, 0400);
1510 static int kcore_copy__unlink(const char *dir
, const char *name
)
1512 char filename
[PATH_MAX
];
1514 scnprintf(filename
, PATH_MAX
, "%s/%s", dir
, name
);
1516 return unlink(filename
);
1519 static int kcore_copy__compare_fds(int from
, int to
)
1527 buf_from
= malloc(page_size
);
1528 buf_to
= malloc(page_size
);
1529 if (!buf_from
|| !buf_to
)
1533 /* Use read because mmap won't work on proc files */
1534 ret
= read(from
, buf_from
, page_size
);
1543 if (readn(to
, buf_to
, len
) != (int)len
)
1546 if (memcmp(buf_from
, buf_to
, len
))
1557 static int kcore_copy__compare_files(const char *from_filename
,
1558 const char *to_filename
)
1560 int from
, to
, err
= -1;
1562 from
= open(from_filename
, O_RDONLY
);
1566 to
= open(to_filename
, O_RDONLY
);
1568 goto out_close_from
;
1570 err
= kcore_copy__compare_fds(from
, to
);
1578 static int kcore_copy__compare_file(const char *from_dir
, const char *to_dir
,
1581 char from_filename
[PATH_MAX
];
1582 char to_filename
[PATH_MAX
];
1584 scnprintf(from_filename
, PATH_MAX
, "%s/%s", from_dir
, name
);
1585 scnprintf(to_filename
, PATH_MAX
, "%s/%s", to_dir
, name
);
1587 return kcore_copy__compare_files(from_filename
, to_filename
);
1591 * kcore_copy - copy kallsyms, modules and kcore from one directory to another.
1592 * @from_dir: from directory
1593 * @to_dir: to directory
1595 * This function copies kallsyms, modules and kcore files from one directory to
1596 * another. kallsyms and modules are copied entirely. Only code segments are
1597 * copied from kcore. It is assumed that two segments suffice: one for the
1598 * kernel proper and one for all the modules. The code segments are determined
1599 * from kallsyms and modules files. The kernel map starts at _stext or the
1600 * lowest function symbol, and ends at _etext or the highest function symbol.
1601 * The module map starts at the lowest module address and ends at the highest
1602 * module symbol. Start addresses are rounded down to the nearest page. End
1603 * addresses are rounded up to the nearest page. An extra page is added to the
1604 * highest kernel symbol and highest module symbol to, hopefully, encompass that
1605 * symbol too. Because it contains only code sections, the resulting kcore is
1606 * unusual. One significant peculiarity is that the mapping (start -> pgoff)
1607 * is not the same for the kernel map and the modules map. That happens because
1608 * the data is copied adjacently whereas the original kcore has gaps. Finally,
1609 * kallsyms and modules files are compared with their copies to check that
1610 * modules have not been loaded or unloaded while the copies were taking place.
1612 * Return: %0 on success, %-1 on failure.
1614 int kcore_copy(const char *from_dir
, const char *to_dir
)
1617 struct kcore extract
;
1619 int idx
= 0, err
= -1;
1620 off_t offset
= page_size
, sz
, modules_offset
= 0;
1621 struct kcore_copy_info kci
= { .stext
= 0, };
1622 char kcore_filename
[PATH_MAX
];
1623 char extract_filename
[PATH_MAX
];
1625 if (kcore_copy__copy_file(from_dir
, to_dir
, "kallsyms"))
1628 if (kcore_copy__copy_file(from_dir
, to_dir
, "modules"))
1629 goto out_unlink_kallsyms
;
1631 scnprintf(kcore_filename
, PATH_MAX
, "%s/kcore", from_dir
);
1632 scnprintf(extract_filename
, PATH_MAX
, "%s/kcore", to_dir
);
1634 if (kcore__open(&kcore
, kcore_filename
))
1635 goto out_unlink_modules
;
1637 if (kcore_copy__calc_maps(&kci
, from_dir
, kcore
.elf
))
1638 goto out_kcore_close
;
1640 if (kcore__init(&extract
, extract_filename
, kcore
.elfclass
, false))
1641 goto out_kcore_close
;
1643 if (!kci
.modules_map
.addr
)
1646 if (kcore__copy_hdr(&kcore
, &extract
, count
))
1647 goto out_extract_close
;
1649 if (kcore__add_phdr(&extract
, idx
++, offset
, kci
.kernel_map
.addr
,
1650 kci
.kernel_map
.len
))
1651 goto out_extract_close
;
1653 if (kci
.modules_map
.addr
) {
1654 modules_offset
= offset
+ kci
.kernel_map
.len
;
1655 if (kcore__add_phdr(&extract
, idx
, modules_offset
,
1656 kci
.modules_map
.addr
, kci
.modules_map
.len
))
1657 goto out_extract_close
;
1660 sz
= kcore__write(&extract
);
1661 if (sz
< 0 || sz
> offset
)
1662 goto out_extract_close
;
1664 if (copy_bytes(kcore
.fd
, kci
.kernel_map
.offset
, extract
.fd
, offset
,
1665 kci
.kernel_map
.len
))
1666 goto out_extract_close
;
1668 if (modules_offset
&& copy_bytes(kcore
.fd
, kci
.modules_map
.offset
,
1669 extract
.fd
, modules_offset
,
1670 kci
.modules_map
.len
))
1671 goto out_extract_close
;
1673 if (kcore_copy__compare_file(from_dir
, to_dir
, "modules"))
1674 goto out_extract_close
;
1676 if (kcore_copy__compare_file(from_dir
, to_dir
, "kallsyms"))
1677 goto out_extract_close
;
1682 kcore__close(&extract
);
1684 unlink(extract_filename
);
1686 kcore__close(&kcore
);
1689 kcore_copy__unlink(to_dir
, "modules");
1690 out_unlink_kallsyms
:
1692 kcore_copy__unlink(to_dir
, "kallsyms");
1697 int kcore_extract__create(struct kcore_extract
*kce
)
1700 struct kcore extract
;
1702 int idx
= 0, err
= -1;
1703 off_t offset
= page_size
, sz
;
1705 if (kcore__open(&kcore
, kce
->kcore_filename
))
1708 strcpy(kce
->extract_filename
, PERF_KCORE_EXTRACT
);
1709 if (kcore__init(&extract
, kce
->extract_filename
, kcore
.elfclass
, true))
1710 goto out_kcore_close
;
1712 if (kcore__copy_hdr(&kcore
, &extract
, count
))
1713 goto out_extract_close
;
1715 if (kcore__add_phdr(&extract
, idx
, offset
, kce
->addr
, kce
->len
))
1716 goto out_extract_close
;
1718 sz
= kcore__write(&extract
);
1719 if (sz
< 0 || sz
> offset
)
1720 goto out_extract_close
;
1722 if (copy_bytes(kcore
.fd
, kce
->offs
, extract
.fd
, offset
, kce
->len
))
1723 goto out_extract_close
;
1728 kcore__close(&extract
);
1730 unlink(kce
->extract_filename
);
1732 kcore__close(&kcore
);
1737 void kcore_extract__delete(struct kcore_extract
*kce
)
1739 unlink(kce
->extract_filename
);
1742 void symbol__elf_init(void)
1744 elf_version(EV_CURRENT
);