1 /* Postprocess module symbol versions
3 * Copyright 2003 Kai Germaschewski
4 * Copyright 2002-2004 Rusty Russell, IBM Corporation
5 * Copyright 2006-2008 Sam Ravnborg
6 * Based in part on module-init-tools/depmod.c,file2alias
8 * This software may be used and distributed according to the terms
9 * of the GNU General Public License, incorporated herein by reference.
11 * Usage: modpost vmlinux module1.o module2.o ...
18 #include "../../include/linux/license.h"
20 /* Are we using CONFIG_MODVERSIONS? */
22 /* Warn about undefined symbols? (do so if we have vmlinux) */
24 /* Is CONFIG_MODULE_SRCVERSION_ALL set? */
25 static int all_versions
= 0;
26 /* If we are modposting external module set to 1 */
27 static int external_module
= 0;
28 /* Warn about section mismatch in vmlinux if set to 1 */
29 static int vmlinux_section_warnings
= 1;
30 /* Only warn about unresolved symbols */
31 static int warn_unresolved
= 0;
32 /* How a symbol is exported */
33 static int sec_mismatch_count
= 0;
34 static int sec_mismatch_verbose
= 1;
37 export_plain
, export_unused
, export_gpl
,
38 export_unused_gpl
, export_gpl_future
, export_unknown
41 #define PRINTF __attribute__ ((format (printf, 1, 2)))
43 PRINTF
void fatal(const char *fmt
, ...)
47 fprintf(stderr
, "FATAL: ");
49 va_start(arglist
, fmt
);
50 vfprintf(stderr
, fmt
, arglist
);
56 PRINTF
void warn(const char *fmt
, ...)
60 fprintf(stderr
, "WARNING: ");
62 va_start(arglist
, fmt
);
63 vfprintf(stderr
, fmt
, arglist
);
67 PRINTF
void merror(const char *fmt
, ...)
71 fprintf(stderr
, "ERROR: ");
73 va_start(arglist
, fmt
);
74 vfprintf(stderr
, fmt
, arglist
);
78 static int is_vmlinux(const char *modname
)
82 myname
= strrchr(modname
, '/');
88 return (strcmp(myname
, "vmlinux") == 0) ||
89 (strcmp(myname
, "vmlinux.o") == 0);
92 void *do_nofail(void *ptr
, const char *expr
)
95 fatal("modpost: Memory allocation failure: %s.\n", expr
);
100 /* A list of all modules we processed */
101 static struct module
*modules
;
103 static struct module
*find_module(char *modname
)
107 for (mod
= modules
; mod
; mod
= mod
->next
)
108 if (strcmp(mod
->name
, modname
) == 0)
113 static struct module
*new_module(char *modname
)
118 mod
= NOFAIL(malloc(sizeof(*mod
)));
119 memset(mod
, 0, sizeof(*mod
));
120 p
= NOFAIL(strdup(modname
));
122 /* strip trailing .o */
125 if (strcmp(s
, ".o") == 0)
130 mod
->gpl_compatible
= -1;
137 /* A hash of all exported symbols,
138 * struct symbol is also used for lists of unresolved symbols */
140 #define SYMBOL_HASH_SIZE 1024
144 struct module
*module
;
148 unsigned int vmlinux
:1; /* 1 if symbol is defined in vmlinux */
149 unsigned int kernel
:1; /* 1 if symbol is from kernel
150 * (only for external modules) **/
151 unsigned int preloaded
:1; /* 1 if symbol from Module.symvers */
152 enum export export
; /* Type of export */
156 static struct symbol
*symbolhash
[SYMBOL_HASH_SIZE
];
158 /* This is based on the hash agorithm from gdbm, via tdb */
159 static inline unsigned int tdb_hash(const char *name
)
161 unsigned value
; /* Used to compute the hash value. */
162 unsigned i
; /* Used to cycle through random values. */
164 /* Set the initial value from the key size. */
165 for (value
= 0x238F13AF * strlen(name
), i
= 0; name
[i
]; i
++)
166 value
= (value
+ (((unsigned char *)name
)[i
] << (i
*5 % 24)));
168 return (1103515243 * value
+ 12345);
172 * Allocate a new symbols for use in the hash of exported symbols or
173 * the list of unresolved symbols per module
175 static struct symbol
*alloc_symbol(const char *name
, unsigned int weak
,
178 struct symbol
*s
= NOFAIL(malloc(sizeof(*s
) + strlen(name
) + 1));
180 memset(s
, 0, sizeof(*s
));
181 strcpy(s
->name
, name
);
187 /* For the hash of exported symbols */
188 static struct symbol
*new_symbol(const char *name
, struct module
*module
,
194 hash
= tdb_hash(name
) % SYMBOL_HASH_SIZE
;
195 new = symbolhash
[hash
] = alloc_symbol(name
, 0, symbolhash
[hash
]);
196 new->module
= module
;
197 new->export
= export
;
201 static struct symbol
*find_symbol(const char *name
)
205 /* For our purposes, .foo matches foo. PPC64 needs this. */
209 for (s
= symbolhash
[tdb_hash(name
) % SYMBOL_HASH_SIZE
]; s
; s
= s
->next
) {
210 if (strcmp(s
->name
, name
) == 0)
220 { .str
= "EXPORT_SYMBOL", .export
= export_plain
},
221 { .str
= "EXPORT_UNUSED_SYMBOL", .export
= export_unused
},
222 { .str
= "EXPORT_SYMBOL_GPL", .export
= export_gpl
},
223 { .str
= "EXPORT_UNUSED_SYMBOL_GPL", .export
= export_unused_gpl
},
224 { .str
= "EXPORT_SYMBOL_GPL_FUTURE", .export
= export_gpl_future
},
225 { .str
= "(unknown)", .export
= export_unknown
},
229 static const char *export_str(enum export ex
)
231 return export_list
[ex
].str
;
234 static enum export
export_no(const char *s
)
239 return export_unknown
;
240 for (i
= 0; export_list
[i
].export
!= export_unknown
; i
++) {
241 if (strcmp(export_list
[i
].str
, s
) == 0)
242 return export_list
[i
].export
;
244 return export_unknown
;
247 static enum export
export_from_sec(struct elf_info
*elf
, Elf_Section sec
)
249 if (sec
== elf
->export_sec
)
251 else if (sec
== elf
->export_unused_sec
)
252 return export_unused
;
253 else if (sec
== elf
->export_gpl_sec
)
255 else if (sec
== elf
->export_unused_gpl_sec
)
256 return export_unused_gpl
;
257 else if (sec
== elf
->export_gpl_future_sec
)
258 return export_gpl_future
;
260 return export_unknown
;
264 * Add an exported symbol - it may have already been added without a
265 * CRC, in this case just update the CRC
267 static struct symbol
*sym_add_exported(const char *name
, struct module
*mod
,
270 struct symbol
*s
= find_symbol(name
);
273 s
= new_symbol(name
, mod
, export
);
276 warn("%s: '%s' exported twice. Previous export "
277 "was in %s%s\n", mod
->name
, name
,
279 is_vmlinux(s
->module
->name
) ?"":".ko");
281 /* In case Modules.symvers was out of date */
286 s
->vmlinux
= is_vmlinux(mod
->name
);
292 static void sym_update_crc(const char *name
, struct module
*mod
,
293 unsigned int crc
, enum export export
)
295 struct symbol
*s
= find_symbol(name
);
298 s
= new_symbol(name
, mod
, export
);
303 void *grab_file(const char *filename
, unsigned long *size
)
309 fd
= open(filename
, O_RDONLY
);
310 if (fd
< 0 || fstat(fd
, &st
) != 0)
314 map
= mmap(NULL
, *size
, PROT_READ
|PROT_WRITE
, MAP_PRIVATE
, fd
, 0);
317 if (map
== MAP_FAILED
)
323 * Return a copy of the next line in a mmap'ed file.
324 * spaces in the beginning of the line is trimmed away.
325 * Return a pointer to a static buffer.
327 char *get_next_line(unsigned long *pos
, void *file
, unsigned long size
)
329 static char line
[4096];
332 signed char *p
= (signed char *)file
+ *pos
;
335 for (; *pos
< size
; (*pos
)++) {
336 if (skip
&& isspace(*p
)) {
341 if (*p
!= '\n' && (*pos
< size
)) {
345 break; /* Too long, stop */
356 void release_file(void *file
, unsigned long size
)
361 static int parse_elf(struct elf_info
*info
, const char *filename
)
368 hdr
= grab_file(filename
, &info
->size
);
374 if (info
->size
< sizeof(*hdr
)) {
375 /* file too small, assume this is an empty .o file */
378 /* Is this a valid ELF file? */
379 if ((hdr
->e_ident
[EI_MAG0
] != ELFMAG0
) ||
380 (hdr
->e_ident
[EI_MAG1
] != ELFMAG1
) ||
381 (hdr
->e_ident
[EI_MAG2
] != ELFMAG2
) ||
382 (hdr
->e_ident
[EI_MAG3
] != ELFMAG3
)) {
383 /* Not an ELF file - silently ignore it */
386 /* Fix endianness in ELF header */
387 hdr
->e_shoff
= TO_NATIVE(hdr
->e_shoff
);
388 hdr
->e_shstrndx
= TO_NATIVE(hdr
->e_shstrndx
);
389 hdr
->e_shnum
= TO_NATIVE(hdr
->e_shnum
);
390 hdr
->e_machine
= TO_NATIVE(hdr
->e_machine
);
391 hdr
->e_type
= TO_NATIVE(hdr
->e_type
);
392 sechdrs
= (void *)hdr
+ hdr
->e_shoff
;
393 info
->sechdrs
= sechdrs
;
395 /* Check if file offset is correct */
396 if (hdr
->e_shoff
> info
->size
) {
397 fatal("section header offset=%lu in file '%s' is bigger than "
398 "filesize=%lu\n", (unsigned long)hdr
->e_shoff
,
399 filename
, info
->size
);
403 /* Fix endianness in section headers */
404 for (i
= 0; i
< hdr
->e_shnum
; i
++) {
405 sechdrs
[i
].sh_type
= TO_NATIVE(sechdrs
[i
].sh_type
);
406 sechdrs
[i
].sh_offset
= TO_NATIVE(sechdrs
[i
].sh_offset
);
407 sechdrs
[i
].sh_size
= TO_NATIVE(sechdrs
[i
].sh_size
);
408 sechdrs
[i
].sh_link
= TO_NATIVE(sechdrs
[i
].sh_link
);
409 sechdrs
[i
].sh_name
= TO_NATIVE(sechdrs
[i
].sh_name
);
410 sechdrs
[i
].sh_info
= TO_NATIVE(sechdrs
[i
].sh_info
);
411 sechdrs
[i
].sh_addr
= TO_NATIVE(sechdrs
[i
].sh_addr
);
413 /* Find symbol table. */
414 for (i
= 1; i
< hdr
->e_shnum
; i
++) {
415 const char *secstrings
416 = (void *)hdr
+ sechdrs
[hdr
->e_shstrndx
].sh_offset
;
419 if (sechdrs
[i
].sh_offset
> info
->size
) {
420 fatal("%s is truncated. sechdrs[i].sh_offset=%lu > "
421 "sizeof(*hrd)=%zu\n", filename
,
422 (unsigned long)sechdrs
[i
].sh_offset
,
426 secname
= secstrings
+ sechdrs
[i
].sh_name
;
427 if (strcmp(secname
, ".modinfo") == 0) {
428 info
->modinfo
= (void *)hdr
+ sechdrs
[i
].sh_offset
;
429 info
->modinfo_len
= sechdrs
[i
].sh_size
;
430 } else if (strcmp(secname
, "__ksymtab") == 0)
431 info
->export_sec
= i
;
432 else if (strcmp(secname
, "__ksymtab_unused") == 0)
433 info
->export_unused_sec
= i
;
434 else if (strcmp(secname
, "__ksymtab_gpl") == 0)
435 info
->export_gpl_sec
= i
;
436 else if (strcmp(secname
, "__ksymtab_unused_gpl") == 0)
437 info
->export_unused_gpl_sec
= i
;
438 else if (strcmp(secname
, "__ksymtab_gpl_future") == 0)
439 info
->export_gpl_future_sec
= i
;
440 else if (strcmp(secname
, "__markers_strings") == 0)
441 info
->markers_strings_sec
= i
;
443 if (sechdrs
[i
].sh_type
!= SHT_SYMTAB
)
446 info
->symtab_start
= (void *)hdr
+ sechdrs
[i
].sh_offset
;
447 info
->symtab_stop
= (void *)hdr
+ sechdrs
[i
].sh_offset
448 + sechdrs
[i
].sh_size
;
449 info
->strtab
= (void *)hdr
+
450 sechdrs
[sechdrs
[i
].sh_link
].sh_offset
;
452 if (!info
->symtab_start
)
453 fatal("%s has no symtab?\n", filename
);
455 /* Fix endianness in symbols */
456 for (sym
= info
->symtab_start
; sym
< info
->symtab_stop
; sym
++) {
457 sym
->st_shndx
= TO_NATIVE(sym
->st_shndx
);
458 sym
->st_name
= TO_NATIVE(sym
->st_name
);
459 sym
->st_value
= TO_NATIVE(sym
->st_value
);
460 sym
->st_size
= TO_NATIVE(sym
->st_size
);
465 static void parse_elf_finish(struct elf_info
*info
)
467 release_file(info
->hdr
, info
->size
);
470 static int ignore_undef_symbol(struct elf_info
*info
, const char *symname
)
472 /* ignore __this_module, it will be resolved shortly */
473 if (strcmp(symname
, MODULE_SYMBOL_PREFIX
"__this_module") == 0)
475 /* ignore global offset table */
476 if (strcmp(symname
, "_GLOBAL_OFFSET_TABLE_") == 0)
478 if (info
->hdr
->e_machine
== EM_PPC
)
479 /* Special register function linked on all modules during final link of .ko */
480 if (strncmp(symname
, "_restgpr_", sizeof("_restgpr_") - 1) == 0 ||
481 strncmp(symname
, "_savegpr_", sizeof("_savegpr_") - 1) == 0 ||
482 strncmp(symname
, "_rest32gpr_", sizeof("_rest32gpr_") - 1) == 0 ||
483 strncmp(symname
, "_save32gpr_", sizeof("_save32gpr_") - 1) == 0)
485 /* Do not ignore this symbol */
489 #define CRC_PFX MODULE_SYMBOL_PREFIX "__crc_"
490 #define KSYMTAB_PFX MODULE_SYMBOL_PREFIX "__ksymtab_"
492 static void handle_modversions(struct module
*mod
, struct elf_info
*info
,
493 Elf_Sym
*sym
, const char *symname
)
496 enum export export
= export_from_sec(info
, sym
->st_shndx
);
498 switch (sym
->st_shndx
) {
500 warn("\"%s\" [%s] is COMMON symbol\n", symname
, mod
->name
);
504 if (memcmp(symname
, CRC_PFX
, strlen(CRC_PFX
)) == 0) {
505 crc
= (unsigned int) sym
->st_value
;
506 sym_update_crc(symname
+ strlen(CRC_PFX
), mod
, crc
,
511 /* undefined symbol */
512 if (ELF_ST_BIND(sym
->st_info
) != STB_GLOBAL
&&
513 ELF_ST_BIND(sym
->st_info
) != STB_WEAK
)
515 if (ignore_undef_symbol(info
, symname
))
517 /* cope with newer glibc (2.3.4 or higher) STT_ definition in elf.h */
518 #if defined(STT_REGISTER) || defined(STT_SPARC_REGISTER)
519 /* add compatibility with older glibc */
520 #ifndef STT_SPARC_REGISTER
521 #define STT_SPARC_REGISTER STT_REGISTER
523 if (info
->hdr
->e_machine
== EM_SPARC
||
524 info
->hdr
->e_machine
== EM_SPARCV9
) {
525 /* Ignore register directives. */
526 if (ELF_ST_TYPE(sym
->st_info
) == STT_SPARC_REGISTER
)
528 if (symname
[0] == '.') {
529 char *munged
= strdup(symname
);
531 munged
[1] = toupper(munged
[1]);
537 if (memcmp(symname
, MODULE_SYMBOL_PREFIX
,
538 strlen(MODULE_SYMBOL_PREFIX
)) == 0) {
540 alloc_symbol(symname
+
541 strlen(MODULE_SYMBOL_PREFIX
),
542 ELF_ST_BIND(sym
->st_info
) == STB_WEAK
,
547 /* All exported symbols */
548 if (memcmp(symname
, KSYMTAB_PFX
, strlen(KSYMTAB_PFX
)) == 0) {
549 sym_add_exported(symname
+ strlen(KSYMTAB_PFX
), mod
,
552 if (strcmp(symname
, MODULE_SYMBOL_PREFIX
"init_module") == 0)
554 if (strcmp(symname
, MODULE_SYMBOL_PREFIX
"cleanup_module") == 0)
555 mod
->has_cleanup
= 1;
561 * Parse tag=value strings from .modinfo section
563 static char *next_string(char *string
, unsigned long *secsize
)
565 /* Skip non-zero chars */
568 if ((*secsize
)-- <= 1)
572 /* Skip any zero padding. */
575 if ((*secsize
)-- <= 1)
581 static char *get_next_modinfo(void *modinfo
, unsigned long modinfo_len
,
582 const char *tag
, char *info
)
585 unsigned int taglen
= strlen(tag
);
586 unsigned long size
= modinfo_len
;
589 size
-= info
- (char *)modinfo
;
590 modinfo
= next_string(info
, &size
);
593 for (p
= modinfo
; p
; p
= next_string(p
, &size
)) {
594 if (strncmp(p
, tag
, taglen
) == 0 && p
[taglen
] == '=')
595 return p
+ taglen
+ 1;
600 static char *get_modinfo(void *modinfo
, unsigned long modinfo_len
,
604 return get_next_modinfo(modinfo
, modinfo_len
, tag
, NULL
);
608 * Test if string s ends in string sub
611 static int strrcmp(const char *s
, const char *sub
)
619 sublen
= strlen(sub
);
621 if ((slen
== 0) || (sublen
== 0))
627 return memcmp(s
+ slen
- sublen
, sub
, sublen
);
630 static const char *sym_name(struct elf_info
*elf
, Elf_Sym
*sym
)
633 return elf
->strtab
+ sym
->st_name
;
638 static const char *sec_name(struct elf_info
*elf
, int shndx
)
640 Elf_Shdr
*sechdrs
= elf
->sechdrs
;
641 return (void *)elf
->hdr
+
642 elf
->sechdrs
[elf
->hdr
->e_shstrndx
].sh_offset
+
643 sechdrs
[shndx
].sh_name
;
646 static const char *sech_name(struct elf_info
*elf
, Elf_Shdr
*sechdr
)
648 return (void *)elf
->hdr
+
649 elf
->sechdrs
[elf
->hdr
->e_shstrndx
].sh_offset
+
653 /* if sym is empty or point to a string
654 * like ".[0-9]+" then return 1.
655 * This is the optional prefix added by ld to some sections
657 static int number_prefix(const char *sym
)
665 if (c
< '0' || c
> '9')
671 /* The pattern is an array of simple patterns.
672 * "foo" will match an exact string equal to "foo"
673 * "*foo" will match a string that ends with "foo"
674 * "foo*" will match a string that begins with "foo"
675 * "foo$" will match a string equal to "foo" or "foo.1"
676 * where the '1' can be any number including several digits.
677 * The $ syntax is for sections where ld append a dot number
678 * to make section name unique.
680 int match(const char *sym
, const char * const pat
[])
685 const char *endp
= p
+ strlen(p
) - 1;
689 if (strrcmp(sym
, p
+ 1) == 0)
693 else if (*endp
== '*') {
694 if (strncmp(sym
, p
, strlen(p
) - 1) == 0)
698 else if (*endp
== '$') {
699 if (strncmp(sym
, p
, strlen(p
) - 1) == 0) {
700 if (number_prefix(sym
+ strlen(p
) - 1))
706 if (strcmp(p
, sym
) == 0)
714 /* sections that we do not want to do full section mismatch check on */
715 static const char *section_white_list
[] =
716 { ".debug*", ".stab*", ".note*", ".got*", ".toc*", NULL
};
719 * Is this section one we do not want to check?
720 * This is often debug sections.
721 * If we are going to check this section then
722 * test if section name ends with a dot and a number.
723 * This is used to find sections where the linker have
724 * appended a dot-number to make the name unique.
725 * The cause of this is often a section specified in assembler
726 * without "ax" / "aw" and the same section used in .c
727 * code where gcc add these.
729 static int check_section(const char *modname
, const char *sec
)
731 const char *e
= sec
+ strlen(sec
) - 1;
732 if (match(sec
, section_white_list
))
735 if (*e
&& isdigit(*e
)) {
736 /* consume all digits */
737 while (*e
&& e
!= sec
&& isdigit(*e
))
739 if (*e
== '.' && !strstr(sec
, ".linkonce")) {
740 warn("%s (%s): unexpected section name.\n"
741 "The (.[number]+) following section name are "
742 "ld generated and not expected.\n"
743 "Did you forget to use \"ax\"/\"aw\" "
745 "Note that for example <linux/init.h> contains\n"
746 "section definitions for use in .S files.\n\n",
755 #define ALL_INIT_DATA_SECTIONS \
756 ".init.data$", ".devinit.data$", ".cpuinit.data$", ".meminit.data$"
757 #define ALL_EXIT_DATA_SECTIONS \
758 ".exit.data$", ".devexit.data$", ".cpuexit.data$", ".memexit.data$"
760 #define ALL_INIT_TEXT_SECTIONS \
761 ".init.text$", ".devinit.text$", ".cpuinit.text$", ".meminit.text$"
762 #define ALL_EXIT_TEXT_SECTIONS \
763 ".exit.text$", ".devexit.text$", ".cpuexit.text$", ".memexit.text$"
765 #define ALL_INIT_SECTIONS ALL_INIT_DATA_SECTIONS, ALL_INIT_TEXT_SECTIONS
766 #define ALL_EXIT_SECTIONS ALL_EXIT_DATA_SECTIONS, ALL_EXIT_TEXT_SECTIONS
768 #define DATA_SECTIONS ".data$", ".data.rel$"
769 #define TEXT_SECTIONS ".text$"
771 #define INIT_SECTIONS ".init.data$", ".init.text$"
772 #define DEV_INIT_SECTIONS ".devinit.data$", ".devinit.text$"
773 #define CPU_INIT_SECTIONS ".cpuinit.data$", ".cpuinit.text$"
774 #define MEM_INIT_SECTIONS ".meminit.data$", ".meminit.text$"
776 #define EXIT_SECTIONS ".exit.data$", ".exit.text$"
777 #define DEV_EXIT_SECTIONS ".devexit.data$", ".devexit.text$"
778 #define CPU_EXIT_SECTIONS ".cpuexit.data$", ".cpuexit.text$"
779 #define MEM_EXIT_SECTIONS ".memexit.data$", ".memexit.text$"
781 /* init data sections */
782 static const char *init_data_sections
[] = { ALL_INIT_DATA_SECTIONS
, NULL
};
784 /* all init sections */
785 static const char *init_sections
[] = { ALL_INIT_SECTIONS
, NULL
};
787 /* All init and exit sections (code + data) */
788 static const char *init_exit_sections
[] =
789 {ALL_INIT_SECTIONS
, ALL_EXIT_SECTIONS
, NULL
};
792 static const char *data_sections
[] = { DATA_SECTIONS
, NULL
};
794 /* sections that may refer to an init/exit section with no warning */
795 static const char *initref_sections
[] =
804 /* symbols in .data that may refer to init/exit sections */
805 static const char *symbol_white_list
[] =
808 "*_template", /* scsi uses *_template a lot */
809 "*_timer", /* arm uses ops structures named _timer a lot */
810 "*_sht", /* scsi also used *_sht to some extent */
818 static const char *head_sections
[] = { ".head.text*", NULL
};
819 static const char *linker_symbols
[] =
820 { "__init_begin", "_sinittext", "_einittext", NULL
};
835 struct sectioncheck
{
836 const char *fromsec
[20];
837 const char *tosec
[20];
838 enum mismatch mismatch
;
841 const struct sectioncheck sectioncheck
[] = {
842 /* Do not reference init/exit code/data from
843 * normal code and data
846 .fromsec
= { TEXT_SECTIONS
, NULL
},
847 .tosec
= { ALL_INIT_SECTIONS
, NULL
},
848 .mismatch
= TEXT_TO_INIT
,
851 .fromsec
= { DATA_SECTIONS
, NULL
},
852 .tosec
= { ALL_INIT_SECTIONS
, NULL
},
853 .mismatch
= DATA_TO_INIT
,
856 .fromsec
= { TEXT_SECTIONS
, NULL
},
857 .tosec
= { ALL_EXIT_SECTIONS
, NULL
},
858 .mismatch
= TEXT_TO_EXIT
,
861 .fromsec
= { DATA_SECTIONS
, NULL
},
862 .tosec
= { ALL_EXIT_SECTIONS
, NULL
},
863 .mismatch
= DATA_TO_EXIT
,
865 /* Do not reference init code/data from devinit/cpuinit/meminit code/data */
867 .fromsec
= { DEV_INIT_SECTIONS
, CPU_INIT_SECTIONS
, MEM_INIT_SECTIONS
, NULL
},
868 .tosec
= { INIT_SECTIONS
, NULL
},
869 .mismatch
= XXXINIT_TO_INIT
,
871 /* Do not reference exit code/data from devexit/cpuexit/memexit code/data */
873 .fromsec
= { DEV_EXIT_SECTIONS
, CPU_EXIT_SECTIONS
, MEM_EXIT_SECTIONS
, NULL
},
874 .tosec
= { EXIT_SECTIONS
, NULL
},
875 .mismatch
= XXXEXIT_TO_EXIT
,
877 /* Do not use exit code/data from init code */
879 .fromsec
= { ALL_INIT_SECTIONS
, NULL
},
880 .tosec
= { ALL_EXIT_SECTIONS
, NULL
},
881 .mismatch
= INIT_TO_EXIT
,
883 /* Do not use init code/data from exit code */
885 .fromsec
= { ALL_EXIT_SECTIONS
, NULL
},
886 .tosec
= { ALL_INIT_SECTIONS
, NULL
},
887 .mismatch
= EXIT_TO_INIT
,
889 /* Do not export init/exit functions or data */
891 .fromsec
= { "__ksymtab*", NULL
},
892 .tosec
= { INIT_SECTIONS
, EXIT_SECTIONS
, NULL
},
893 .mismatch
= EXPORT_TO_INIT_EXIT
897 static int section_mismatch(const char *fromsec
, const char *tosec
)
900 int elems
= sizeof(sectioncheck
) / sizeof(struct sectioncheck
);
901 const struct sectioncheck
*check
= §ioncheck
[0];
903 for (i
= 0; i
< elems
; i
++) {
904 if (match(fromsec
, check
->fromsec
) &&
905 match(tosec
, check
->tosec
))
906 return check
->mismatch
;
913 * Whitelist to allow certain references to pass with no warning.
916 * Do not warn if funtion/data are marked with __init_refok/__initdata_refok.
917 * The pattern is identified by:
918 * fromsec = .text.init.refok* | .data.init.refok*
921 * If a module parameter is declared __initdata and permissions=0
922 * then this is legal despite the warning generated.
923 * We cannot see value of permissions here, so just ignore
925 * The pattern is identified by:
931 * Many drivers utilise a *driver container with references to
932 * add, remove, probe functions etc.
933 * These functions may often be marked __init and we do not want to
935 * the pattern is identified by:
936 * tosec = init or exit section
937 * fromsec = data section
938 * atsym = *driver, *_template, *_sht, *_ops, *_probe,
939 * *probe_one, *_console, *_timer
942 * Whitelist all refereces from .text.head to .init.data
943 * Whitelist all refereces from .text.head to .init.text
946 * Some symbols belong to init section but still it is ok to reference
947 * these from non-init sections as these symbols don't have any memory
948 * allocated for them and symbol address and value are same. So even
949 * if init section is freed, its ok to reference those symbols.
950 * For ex. symbols marking the init section boundaries.
951 * This pattern is identified by
952 * refsymname = __init_begin, _sinittext, _einittext
955 static int secref_whitelist(const char *fromsec
, const char *fromsym
,
956 const char *tosec
, const char *tosym
)
958 /* Check for pattern 0 */
959 if (match(fromsec
, initref_sections
))
962 /* Check for pattern 1 */
963 if (match(tosec
, init_data_sections
) &&
964 match(fromsec
, data_sections
) &&
965 (strncmp(fromsym
, "__param", strlen("__param")) == 0))
968 /* Check for pattern 2 */
969 if (match(tosec
, init_exit_sections
) &&
970 match(fromsec
, data_sections
) &&
971 match(fromsym
, symbol_white_list
))
974 /* Check for pattern 3 */
975 if (match(fromsec
, head_sections
) &&
976 match(tosec
, init_sections
))
979 /* Check for pattern 4 */
980 if (match(tosym
, linker_symbols
))
987 * Find symbol based on relocation record info.
988 * In some cases the symbol supplied is a valid symbol so
989 * return refsym. If st_name != 0 we assume this is a valid symbol.
990 * In other cases the symbol needs to be looked up in the symbol table
991 * based on section and address.
993 static Elf_Sym
*find_elf_symbol(struct elf_info
*elf
, Elf64_Sword addr
,
997 Elf_Sym
*near
= NULL
;
998 Elf64_Sword distance
= 20;
1001 if (relsym
->st_name
!= 0)
1003 for (sym
= elf
->symtab_start
; sym
< elf
->symtab_stop
; sym
++) {
1004 if (sym
->st_shndx
!= relsym
->st_shndx
)
1006 if (ELF_ST_TYPE(sym
->st_info
) == STT_SECTION
)
1008 if (sym
->st_value
== addr
)
1010 /* Find a symbol nearby - addr are maybe negative */
1011 d
= sym
->st_value
- addr
;
1013 d
= addr
- sym
->st_value
;
1019 /* We need a close match */
1026 static inline int is_arm_mapping_symbol(const char *str
)
1028 return str
[0] == '$' && strchr("atd", str
[1])
1029 && (str
[2] == '\0' || str
[2] == '.');
1033 * If there's no name there, ignore it; likewise, ignore it if it's
1034 * one of the magic symbols emitted used by current ARM tools.
1036 * Otherwise if find_symbols_between() returns those symbols, they'll
1037 * fail the whitelist tests and cause lots of false alarms ... fixable
1038 * only by merging __exit and __init sections into __text, bloating
1039 * the kernel (which is especially evil on embedded platforms).
1041 static inline int is_valid_name(struct elf_info
*elf
, Elf_Sym
*sym
)
1043 const char *name
= elf
->strtab
+ sym
->st_name
;
1045 if (!name
|| !strlen(name
))
1047 return !is_arm_mapping_symbol(name
);
1051 * Find symbols before or equal addr and after addr - in the section sec.
1052 * If we find two symbols with equal offset prefer one with a valid name.
1053 * The ELF format may have a better way to detect what type of symbol
1054 * it is, but this works for now.
1056 static Elf_Sym
*find_elf_symbol2(struct elf_info
*elf
, Elf_Addr addr
,
1060 Elf_Sym
*near
= NULL
;
1061 Elf_Addr distance
= ~0;
1063 for (sym
= elf
->symtab_start
; sym
< elf
->symtab_stop
; sym
++) {
1066 if (sym
->st_shndx
>= SHN_LORESERVE
)
1068 symsec
= sec_name(elf
, sym
->st_shndx
);
1069 if (strcmp(symsec
, sec
) != 0)
1071 if (!is_valid_name(elf
, sym
))
1073 if (sym
->st_value
<= addr
) {
1074 if ((addr
- sym
->st_value
) < distance
) {
1075 distance
= addr
- sym
->st_value
;
1077 } else if ((addr
- sym
->st_value
) == distance
) {
1086 * Convert a section name to the function/data attribute
1087 * .init.text => __init
1088 * .cpuinit.data => __cpudata
1089 * .memexitconst => __memconst
1092 static char *sec2annotation(const char *s
)
1094 if (match(s
, init_exit_sections
)) {
1095 char *p
= malloc(20);
1102 while (*s
&& *s
!= '.')
1107 if (strstr(s
, "rodata") != NULL
)
1108 strcat(p
, "const ");
1109 else if (strstr(s
, "data") != NULL
)
1113 return r
; /* we leak her but we do not care */
1119 static int is_function(Elf_Sym
*sym
)
1122 return ELF_ST_TYPE(sym
->st_info
) == STT_FUNC
;
1128 * Print a warning about a section mismatch.
1129 * Try to find symbols near it so user can find it.
1130 * Check whitelist before warning - it may be a false positive.
1132 static void report_sec_mismatch(const char *modname
, enum mismatch mismatch
,
1133 const char *fromsec
,
1134 unsigned long long fromaddr
,
1135 const char *fromsym
,
1137 const char *tosec
, const char *tosym
,
1140 const char *from
, *from_p
;
1141 const char *to
, *to_p
;
1143 switch (from_is_func
) {
1144 case 0: from
= "variable"; from_p
= ""; break;
1145 case 1: from
= "function"; from_p
= "()"; break;
1146 default: from
= "(unknown reference)"; from_p
= ""; break;
1148 switch (to_is_func
) {
1149 case 0: to
= "variable"; to_p
= ""; break;
1150 case 1: to
= "function"; to_p
= "()"; break;
1151 default: to
= "(unknown reference)"; to_p
= ""; break;
1154 sec_mismatch_count
++;
1155 if (!sec_mismatch_verbose
)
1158 warn("%s(%s+0x%llx): Section mismatch in reference from the %s %s%s "
1159 "to the %s %s:%s%s\n",
1160 modname
, fromsec
, fromaddr
, from
, fromsym
, from_p
, to
, tosec
,
1166 "The function %s%s() references\n"
1168 "This is often because %s lacks a %s\n"
1169 "annotation or the annotation of %s is wrong.\n",
1170 sec2annotation(fromsec
), fromsym
,
1171 to
, sec2annotation(tosec
), tosym
, to_p
,
1172 fromsym
, sec2annotation(tosec
), tosym
);
1174 case DATA_TO_INIT
: {
1175 const char **s
= symbol_white_list
;
1177 "The variable %s references\n"
1179 "If the reference is valid then annotate the\n"
1180 "variable with __init* (see linux/init.h) "
1181 "or name the variable:\n",
1182 fromsym
, to
, sec2annotation(tosec
), tosym
, to_p
);
1184 fprintf(stderr
, "%s, ", *s
++);
1185 fprintf(stderr
, "\n");
1190 "The function %s() references a %s in an exit section.\n"
1191 "Often the %s %s%s has valid usage outside the exit section\n"
1192 "and the fix is to remove the %sannotation of %s.\n",
1193 fromsym
, to
, to
, tosym
, to_p
, sec2annotation(tosec
), tosym
);
1195 case DATA_TO_EXIT
: {
1196 const char **s
= symbol_white_list
;
1198 "The variable %s references\n"
1200 "If the reference is valid then annotate the\n"
1201 "variable with __exit* (see linux/init.h) or "
1202 "name the variable:\n",
1203 fromsym
, to
, sec2annotation(tosec
), tosym
, to_p
);
1205 fprintf(stderr
, "%s, ", *s
++);
1206 fprintf(stderr
, "\n");
1209 case XXXINIT_TO_INIT
:
1210 case XXXEXIT_TO_EXIT
:
1212 "The %s %s%s%s references\n"
1214 "If %s is only used by %s then\n"
1215 "annotate %s with a matching annotation.\n",
1216 from
, sec2annotation(fromsec
), fromsym
, from_p
,
1217 to
, sec2annotation(tosec
), tosym
, to_p
,
1218 tosym
, fromsym
, tosym
);
1222 "The %s %s%s%s references\n"
1224 "This is often seen when error handling "
1225 "in the init function\n"
1226 "uses functionality in the exit path.\n"
1227 "The fix is often to remove the %sannotation of\n"
1228 "%s%s so it may be used outside an exit section.\n",
1229 from
, sec2annotation(fromsec
), fromsym
, from_p
,
1230 to
, sec2annotation(tosec
), tosym
, to_p
,
1231 sec2annotation(tosec
), tosym
, to_p
);
1235 "The %s %s%s%s references\n"
1237 "This is often seen when error handling "
1238 "in the exit function\n"
1239 "uses functionality in the init path.\n"
1240 "The fix is often to remove the %sannotation of\n"
1241 "%s%s so it may be used outside an init section.\n",
1242 from
, sec2annotation(fromsec
), fromsym
, from_p
,
1243 to
, sec2annotation(tosec
), tosym
, to_p
,
1244 sec2annotation(tosec
), tosym
, to_p
);
1246 case EXPORT_TO_INIT_EXIT
:
1248 "The symbol %s is exported and annotated %s\n"
1249 "Fix this by removing the %sannotation of %s "
1250 "or drop the export.\n",
1251 tosym
, sec2annotation(tosec
), sec2annotation(tosec
), tosym
);
1253 /* To get warnings on missing members */
1256 fprintf(stderr
, "\n");
1259 static void check_section_mismatch(const char *modname
, struct elf_info
*elf
,
1260 Elf_Rela
*r
, Elf_Sym
*sym
, const char *fromsec
)
1263 enum mismatch mismatch
;
1265 tosec
= sec_name(elf
, sym
->st_shndx
);
1266 mismatch
= section_mismatch(fromsec
, tosec
);
1267 if (mismatch
!= NO_MISMATCH
) {
1271 const char *fromsym
;
1273 from
= find_elf_symbol2(elf
, r
->r_offset
, fromsec
);
1274 fromsym
= sym_name(elf
, from
);
1275 to
= find_elf_symbol(elf
, r
->r_addend
, sym
);
1276 tosym
= sym_name(elf
, to
);
1278 /* check whitelist - we may ignore it */
1279 if (secref_whitelist(fromsec
, fromsym
, tosec
, tosym
)) {
1280 report_sec_mismatch(modname
, mismatch
,
1281 fromsec
, r
->r_offset
, fromsym
,
1282 is_function(from
), tosec
, tosym
,
1288 static unsigned int *reloc_location(struct elf_info
*elf
,
1289 Elf_Shdr
*sechdr
, Elf_Rela
*r
)
1291 Elf_Shdr
*sechdrs
= elf
->sechdrs
;
1292 int section
= sechdr
->sh_info
;
1294 return (void *)elf
->hdr
+ sechdrs
[section
].sh_offset
+
1295 (r
->r_offset
- sechdrs
[section
].sh_addr
);
1298 static int addend_386_rel(struct elf_info
*elf
, Elf_Shdr
*sechdr
, Elf_Rela
*r
)
1300 unsigned int r_typ
= ELF_R_TYPE(r
->r_info
);
1301 unsigned int *location
= reloc_location(elf
, sechdr
, r
);
1305 r
->r_addend
= TO_NATIVE(*location
);
1308 r
->r_addend
= TO_NATIVE(*location
) + 4;
1309 /* For CONFIG_RELOCATABLE=y */
1310 if (elf
->hdr
->e_type
== ET_EXEC
)
1311 r
->r_addend
+= r
->r_offset
;
1317 static int addend_arm_rel(struct elf_info
*elf
, Elf_Shdr
*sechdr
, Elf_Rela
*r
)
1319 unsigned int r_typ
= ELF_R_TYPE(r
->r_info
);
1323 /* From ARM ABI: (S + A) | T */
1324 r
->r_addend
= (int)(long)
1325 (elf
->symtab_start
+ ELF_R_SYM(r
->r_info
));
1328 /* From ARM ABI: ((S + A) | T) - P */
1329 r
->r_addend
= (int)(long)(elf
->hdr
+
1331 (r
->r_offset
- sechdr
->sh_addr
));
1339 static int addend_mips_rel(struct elf_info
*elf
, Elf_Shdr
*sechdr
, Elf_Rela
*r
)
1341 unsigned int r_typ
= ELF_R_TYPE(r
->r_info
);
1342 unsigned int *location
= reloc_location(elf
, sechdr
, r
);
1345 if (r_typ
== R_MIPS_HI16
)
1346 return 1; /* skip this */
1347 inst
= TO_NATIVE(*location
);
1350 r
->r_addend
= inst
& 0xffff;
1353 r
->r_addend
= (inst
& 0x03ffffff) << 2;
1362 static void section_rela(const char *modname
, struct elf_info
*elf
,
1369 const char *fromsec
;
1371 Elf_Rela
*start
= (void *)elf
->hdr
+ sechdr
->sh_offset
;
1372 Elf_Rela
*stop
= (void *)start
+ sechdr
->sh_size
;
1374 fromsec
= sech_name(elf
, sechdr
);
1375 fromsec
+= strlen(".rela");
1376 /* if from section (name) is know good then skip it */
1377 if (check_section(modname
, fromsec
))
1380 for (rela
= start
; rela
< stop
; rela
++) {
1381 r
.r_offset
= TO_NATIVE(rela
->r_offset
);
1382 #if KERNEL_ELFCLASS == ELFCLASS64
1383 if (elf
->hdr
->e_machine
== EM_MIPS
) {
1385 r_sym
= ELF64_MIPS_R_SYM(rela
->r_info
);
1386 r_sym
= TO_NATIVE(r_sym
);
1387 r_typ
= ELF64_MIPS_R_TYPE(rela
->r_info
);
1388 r
.r_info
= ELF64_R_INFO(r_sym
, r_typ
);
1390 r
.r_info
= TO_NATIVE(rela
->r_info
);
1391 r_sym
= ELF_R_SYM(r
.r_info
);
1394 r
.r_info
= TO_NATIVE(rela
->r_info
);
1395 r_sym
= ELF_R_SYM(r
.r_info
);
1397 r
.r_addend
= TO_NATIVE(rela
->r_addend
);
1398 sym
= elf
->symtab_start
+ r_sym
;
1399 /* Skip special sections */
1400 if (sym
->st_shndx
>= SHN_LORESERVE
)
1402 check_section_mismatch(modname
, elf
, &r
, sym
, fromsec
);
1406 static void section_rel(const char *modname
, struct elf_info
*elf
,
1413 const char *fromsec
;
1415 Elf_Rel
*start
= (void *)elf
->hdr
+ sechdr
->sh_offset
;
1416 Elf_Rel
*stop
= (void *)start
+ sechdr
->sh_size
;
1418 fromsec
= sech_name(elf
, sechdr
);
1419 fromsec
+= strlen(".rel");
1420 /* if from section (name) is know good then skip it */
1421 if (check_section(modname
, fromsec
))
1424 for (rel
= start
; rel
< stop
; rel
++) {
1425 r
.r_offset
= TO_NATIVE(rel
->r_offset
);
1426 #if KERNEL_ELFCLASS == ELFCLASS64
1427 if (elf
->hdr
->e_machine
== EM_MIPS
) {
1429 r_sym
= ELF64_MIPS_R_SYM(rel
->r_info
);
1430 r_sym
= TO_NATIVE(r_sym
);
1431 r_typ
= ELF64_MIPS_R_TYPE(rel
->r_info
);
1432 r
.r_info
= ELF64_R_INFO(r_sym
, r_typ
);
1434 r
.r_info
= TO_NATIVE(rel
->r_info
);
1435 r_sym
= ELF_R_SYM(r
.r_info
);
1438 r
.r_info
= TO_NATIVE(rel
->r_info
);
1439 r_sym
= ELF_R_SYM(r
.r_info
);
1442 switch (elf
->hdr
->e_machine
) {
1444 if (addend_386_rel(elf
, sechdr
, &r
))
1448 if (addend_arm_rel(elf
, sechdr
, &r
))
1452 if (addend_mips_rel(elf
, sechdr
, &r
))
1456 sym
= elf
->symtab_start
+ r_sym
;
1457 /* Skip special sections */
1458 if (sym
->st_shndx
>= SHN_LORESERVE
)
1460 check_section_mismatch(modname
, elf
, &r
, sym
, fromsec
);
1465 * A module includes a number of sections that are discarded
1466 * either when loaded or when used as built-in.
1467 * For loaded modules all functions marked __init and all data
1468 * marked __initdata will be discarded when the module has been intialized.
1469 * Likewise for modules used built-in the sections marked __exit
1470 * are discarded because __exit marked function are supposed to be called
1471 * only when a module is unloaded which never happens for built-in modules.
1472 * The check_sec_ref() function traverses all relocation records
1473 * to find all references to a section that reference a section that will
1474 * be discarded and warns about it.
1476 static void check_sec_ref(struct module
*mod
, const char *modname
,
1477 struct elf_info
*elf
)
1480 Elf_Shdr
*sechdrs
= elf
->sechdrs
;
1482 /* Walk through all sections */
1483 for (i
= 0; i
< elf
->hdr
->e_shnum
; i
++) {
1484 /* We want to process only relocation sections and not .init */
1485 if (sechdrs
[i
].sh_type
== SHT_RELA
)
1486 section_rela(modname
, elf
, &elf
->sechdrs
[i
]);
1487 else if (sechdrs
[i
].sh_type
== SHT_REL
)
1488 section_rel(modname
, elf
, &elf
->sechdrs
[i
]);
1492 static void get_markers(struct elf_info
*info
, struct module
*mod
)
1494 const Elf_Shdr
*sh
= &info
->sechdrs
[info
->markers_strings_sec
];
1495 const char *strings
= (const char *) info
->hdr
+ sh
->sh_offset
;
1496 const Elf_Sym
*sym
, *first_sym
, *last_sym
;
1499 if (!info
->markers_strings_sec
)
1503 * First count the strings. We look for all the symbols defined
1504 * in the __markers_strings section named __mstrtab_*. For
1505 * these local names, the compiler puts a random .NNN suffix on,
1506 * so the names don't correspond exactly.
1508 first_sym
= last_sym
= NULL
;
1510 for (sym
= info
->symtab_start
; sym
< info
->symtab_stop
; sym
++)
1511 if (ELF_ST_TYPE(sym
->st_info
) == STT_OBJECT
&&
1512 sym
->st_shndx
== info
->markers_strings_sec
&&
1513 !strncmp(info
->strtab
+ sym
->st_name
,
1514 "__mstrtab_", sizeof "__mstrtab_" - 1)) {
1515 if (first_sym
== NULL
)
1525 * Now collect each name and format into a line for the output.
1527 * marker_name vmlinux marker %s format %d
1528 * The format string after the second \t can use whitespace.
1530 mod
->markers
= NOFAIL(malloc(sizeof mod
->markers
[0] * n
));
1534 for (sym
= first_sym
; sym
<= last_sym
; sym
++)
1535 if (ELF_ST_TYPE(sym
->st_info
) == STT_OBJECT
&&
1536 sym
->st_shndx
== info
->markers_strings_sec
&&
1537 !strncmp(info
->strtab
+ sym
->st_name
,
1538 "__mstrtab_", sizeof "__mstrtab_" - 1)) {
1539 const char *name
= strings
+ sym
->st_value
;
1540 const char *fmt
= strchr(name
, '\0') + 1;
1542 asprintf(&line
, "%s\t%s\t%s\n", name
, mod
->name
, fmt
);
1544 mod
->markers
[n
++] = line
;
1548 static void read_symbols(char *modname
)
1550 const char *symname
;
1554 struct elf_info info
= { };
1557 if (!parse_elf(&info
, modname
))
1560 mod
= new_module(modname
);
1562 /* When there's no vmlinux, don't print warnings about
1563 * unresolved symbols (since there'll be too many ;) */
1564 if (is_vmlinux(modname
)) {
1569 license
= get_modinfo(info
.modinfo
, info
.modinfo_len
, "license");
1570 if (info
.modinfo
&& !license
&& !is_vmlinux(modname
))
1571 warn("modpost: missing MODULE_LICENSE() in %s\n"
1572 "see include/linux/module.h for "
1573 "more information\n", modname
);
1575 if (license_is_gpl_compatible(license
))
1576 mod
->gpl_compatible
= 1;
1578 mod
->gpl_compatible
= 0;
1581 license
= get_next_modinfo(info
.modinfo
, info
.modinfo_len
,
1582 "license", license
);
1585 for (sym
= info
.symtab_start
; sym
< info
.symtab_stop
; sym
++) {
1586 symname
= info
.strtab
+ sym
->st_name
;
1588 handle_modversions(mod
, &info
, sym
, symname
);
1589 handle_moddevtable(mod
, &info
, sym
, symname
);
1591 if (!is_vmlinux(modname
) ||
1592 (is_vmlinux(modname
) && vmlinux_section_warnings
))
1593 check_sec_ref(mod
, modname
, &info
);
1595 version
= get_modinfo(info
.modinfo
, info
.modinfo_len
, "version");
1597 maybe_frob_rcs_version(modname
, version
, info
.modinfo
,
1598 version
- (char *)info
.hdr
);
1599 if (version
|| (all_versions
&& !is_vmlinux(modname
)))
1600 get_src_version(modname
, mod
->srcversion
,
1601 sizeof(mod
->srcversion
)-1);
1603 get_markers(&info
, mod
);
1605 parse_elf_finish(&info
);
1607 /* Our trick to get versioning for struct_module - it's
1608 * never passed as an argument to an exported function, so
1609 * the automatic versioning doesn't pick it up, but it's really
1610 * important anyhow */
1612 mod
->unres
= alloc_symbol("struct_module", 0, mod
->unres
);
1617 /* We first write the generated file into memory using the
1618 * following helper, then compare to the file on disk and
1619 * only update the later if anything changed */
1621 void __attribute__((format(printf
, 2, 3))) buf_printf(struct buffer
*buf
,
1622 const char *fmt
, ...)
1629 len
= vsnprintf(tmp
, SZ
, fmt
, ap
);
1630 buf_write(buf
, tmp
, len
);
1634 void buf_write(struct buffer
*buf
, const char *s
, int len
)
1636 if (buf
->size
- buf
->pos
< len
) {
1637 buf
->size
+= len
+ SZ
;
1638 buf
->p
= realloc(buf
->p
, buf
->size
);
1640 strncpy(buf
->p
+ buf
->pos
, s
, len
);
1644 static void check_for_gpl_usage(enum export exp
, const char *m
, const char *s
)
1646 const char *e
= is_vmlinux(m
) ?"":".ko";
1650 fatal("modpost: GPL-incompatible module %s%s "
1651 "uses GPL-only symbol '%s'\n", m
, e
, s
);
1653 case export_unused_gpl
:
1654 fatal("modpost: GPL-incompatible module %s%s "
1655 "uses GPL-only symbol marked UNUSED '%s'\n", m
, e
, s
);
1657 case export_gpl_future
:
1658 warn("modpost: GPL-incompatible module %s%s "
1659 "uses future GPL-only symbol '%s'\n", m
, e
, s
);
1663 case export_unknown
:
1669 static void check_for_unused(enum export exp
, const char *m
, const char *s
)
1671 const char *e
= is_vmlinux(m
) ?"":".ko";
1675 case export_unused_gpl
:
1676 warn("modpost: module %s%s "
1677 "uses symbol '%s' marked UNUSED\n", m
, e
, s
);
1685 static void check_exports(struct module
*mod
)
1687 struct symbol
*s
, *exp
;
1689 for (s
= mod
->unres
; s
; s
= s
->next
) {
1690 const char *basename
;
1691 exp
= find_symbol(s
->name
);
1692 if (!exp
|| exp
->module
== mod
)
1694 basename
= strrchr(mod
->name
, '/');
1698 basename
= mod
->name
;
1699 if (!mod
->gpl_compatible
)
1700 check_for_gpl_usage(exp
->export
, basename
, exp
->name
);
1701 check_for_unused(exp
->export
, basename
, exp
->name
);
1706 * Header for the generated file
1708 static void add_header(struct buffer
*b
, struct module
*mod
)
1710 buf_printf(b
, "#include <linux/module.h>\n");
1711 buf_printf(b
, "#include <linux/vermagic.h>\n");
1712 buf_printf(b
, "#include <linux/compiler.h>\n");
1713 buf_printf(b
, "\n");
1714 buf_printf(b
, "MODULE_INFO(vermagic, VERMAGIC_STRING);\n");
1715 buf_printf(b
, "\n");
1716 buf_printf(b
, "struct module __this_module\n");
1717 buf_printf(b
, "__attribute__((section(\".gnu.linkonce.this_module\"))) = {\n");
1718 buf_printf(b
, " .name = KBUILD_MODNAME,\n");
1720 buf_printf(b
, " .init = init_module,\n");
1721 if (mod
->has_cleanup
)
1722 buf_printf(b
, "#ifdef CONFIG_MODULE_UNLOAD\n"
1723 " .exit = cleanup_module,\n"
1725 buf_printf(b
, " .arch = MODULE_ARCH_INIT,\n");
1726 buf_printf(b
, "};\n");
1730 * Record CRCs for unresolved symbols
1732 static int add_versions(struct buffer
*b
, struct module
*mod
)
1734 struct symbol
*s
, *exp
;
1737 for (s
= mod
->unres
; s
; s
= s
->next
) {
1738 exp
= find_symbol(s
->name
);
1739 if (!exp
|| exp
->module
== mod
) {
1740 if (have_vmlinux
&& !s
->weak
) {
1741 if (warn_unresolved
) {
1742 warn("\"%s\" [%s.ko] undefined!\n",
1743 s
->name
, mod
->name
);
1745 merror("\"%s\" [%s.ko] undefined!\n",
1746 s
->name
, mod
->name
);
1752 s
->module
= exp
->module
;
1753 s
->crc_valid
= exp
->crc_valid
;
1760 buf_printf(b
, "\n");
1761 buf_printf(b
, "static const struct modversion_info ____versions[]\n");
1762 buf_printf(b
, "__used\n");
1763 buf_printf(b
, "__attribute__((section(\"__versions\"))) = {\n");
1765 for (s
= mod
->unres
; s
; s
= s
->next
) {
1768 if (!s
->crc_valid
) {
1769 warn("\"%s\" [%s.ko] has no CRC!\n",
1770 s
->name
, mod
->name
);
1773 buf_printf(b
, "\t{ %#8x, \"%s\" },\n", s
->crc
, s
->name
);
1776 buf_printf(b
, "};\n");
1781 static void add_depends(struct buffer
*b
, struct module
*mod
,
1782 struct module
*modules
)
1788 for (m
= modules
; m
; m
= m
->next
)
1789 m
->seen
= is_vmlinux(m
->name
);
1791 buf_printf(b
, "\n");
1792 buf_printf(b
, "static const char __module_depends[]\n");
1793 buf_printf(b
, "__used\n");
1794 buf_printf(b
, "__attribute__((section(\".modinfo\"))) =\n");
1795 buf_printf(b
, "\"depends=");
1796 for (s
= mod
->unres
; s
; s
= s
->next
) {
1801 if (s
->module
->seen
)
1804 s
->module
->seen
= 1;
1805 p
= strrchr(s
->module
->name
, '/');
1809 p
= s
->module
->name
;
1810 buf_printf(b
, "%s%s", first
? "" : ",", p
);
1813 buf_printf(b
, "\";\n");
1816 static void add_srcversion(struct buffer
*b
, struct module
*mod
)
1818 if (mod
->srcversion
[0]) {
1819 buf_printf(b
, "\n");
1820 buf_printf(b
, "MODULE_INFO(srcversion, \"%s\");\n",
1825 static void write_if_changed(struct buffer
*b
, const char *fname
)
1831 file
= fopen(fname
, "r");
1835 if (fstat(fileno(file
), &st
) < 0)
1838 if (st
.st_size
!= b
->pos
)
1841 tmp
= NOFAIL(malloc(b
->pos
));
1842 if (fread(tmp
, 1, b
->pos
, file
) != b
->pos
)
1845 if (memcmp(tmp
, b
->p
, b
->pos
) != 0)
1857 file
= fopen(fname
, "w");
1862 if (fwrite(b
->p
, 1, b
->pos
, file
) != b
->pos
) {
1869 /* parse Module.symvers file. line format:
1870 * 0x12345678<tab>symbol<tab>module[[<tab>export]<tab>something]
1872 static void read_dump(const char *fname
, unsigned int kernel
)
1874 unsigned long size
, pos
= 0;
1875 void *file
= grab_file(fname
, &size
);
1879 /* No symbol versions, silently ignore */
1882 while ((line
= get_next_line(&pos
, file
, size
))) {
1883 char *symname
, *modname
, *d
, *export
, *end
;
1888 if (!(symname
= strchr(line
, '\t')))
1891 if (!(modname
= strchr(symname
, '\t')))
1894 if ((export
= strchr(modname
, '\t')) != NULL
)
1896 if (export
&& ((end
= strchr(export
, '\t')) != NULL
))
1898 crc
= strtoul(line
, &d
, 16);
1899 if (*symname
== '\0' || *modname
== '\0' || *d
!= '\0')
1901 mod
= find_module(modname
);
1903 if (is_vmlinux(modname
))
1905 mod
= new_module(NOFAIL(strdup(modname
)));
1908 s
= sym_add_exported(symname
, mod
, export_no(export
));
1911 sym_update_crc(symname
, mod
, crc
, export_no(export
));
1915 fatal("parse error in symbol dump file\n");
1918 /* For normal builds always dump all symbols.
1919 * For external modules only dump symbols
1920 * that are not read from kernel Module.symvers.
1922 static int dump_sym(struct symbol
*sym
)
1924 if (!external_module
)
1926 if (sym
->vmlinux
|| sym
->kernel
)
1931 static void write_dump(const char *fname
)
1933 struct buffer buf
= { };
1934 struct symbol
*symbol
;
1937 for (n
= 0; n
< SYMBOL_HASH_SIZE
; n
++) {
1938 symbol
= symbolhash
[n
];
1940 if (dump_sym(symbol
))
1941 buf_printf(&buf
, "0x%08x\t%s\t%s\t%s\n",
1942 symbol
->crc
, symbol
->name
,
1943 symbol
->module
->name
,
1944 export_str(symbol
->export
));
1945 symbol
= symbol
->next
;
1948 write_if_changed(&buf
, fname
);
1951 static void add_marker(struct module
*mod
, const char *name
, const char *fmt
)
1954 asprintf(&line
, "%s\t%s\t%s\n", name
, mod
->name
, fmt
);
1957 mod
->markers
= NOFAIL(realloc(mod
->markers
, ((mod
->nmarkers
+ 1) *
1958 sizeof mod
->markers
[0])));
1959 mod
->markers
[mod
->nmarkers
++] = line
;
1962 static void read_markers(const char *fname
)
1964 unsigned long size
, pos
= 0;
1965 void *file
= grab_file(fname
, &size
);
1968 if (!file
) /* No old markers, silently ignore */
1971 while ((line
= get_next_line(&pos
, file
, size
))) {
1972 char *marker
, *modname
, *fmt
;
1976 modname
= strchr(marker
, '\t');
1980 fmt
= strchr(modname
, '\t');
1984 if (*marker
== '\0' || *modname
== '\0')
1987 mod
= find_module(modname
);
1989 if (is_vmlinux(modname
))
1991 mod
= new_module(NOFAIL(strdup(modname
)));
1996 add_marker(mod
, marker
, fmt
);
2000 fatal("parse error in markers list file\n");
2003 static int compare_strings(const void *a
, const void *b
)
2005 return strcmp(*(const char **) a
, *(const char **) b
);
2008 static void write_markers(const char *fname
)
2010 struct buffer buf
= { };
2014 for (mod
= modules
; mod
; mod
= mod
->next
)
2015 if ((!external_module
|| !mod
->skip
) && mod
->markers
!= NULL
) {
2017 * Sort the strings so we can skip duplicates when
2018 * we write them out.
2020 qsort(mod
->markers
, mod
->nmarkers
,
2021 sizeof mod
->markers
[0], &compare_strings
);
2022 for (i
= 0; i
< mod
->nmarkers
; ++i
) {
2023 char *line
= mod
->markers
[i
];
2024 buf_write(&buf
, line
, strlen(line
));
2025 while (i
+ 1 < mod
->nmarkers
&&
2026 !strcmp(mod
->markers
[i
],
2027 mod
->markers
[i
+ 1]))
2028 free(mod
->markers
[i
++]);
2029 free(mod
->markers
[i
]);
2032 mod
->markers
= NULL
;
2035 write_if_changed(&buf
, fname
);
2038 struct ext_sym_list
{
2039 struct ext_sym_list
*next
;
2043 int main(int argc
, char **argv
)
2046 struct buffer buf
= { };
2047 char *kernel_read
= NULL
, *module_read
= NULL
;
2048 char *dump_write
= NULL
;
2049 char *markers_read
= NULL
;
2050 char *markers_write
= NULL
;
2053 struct ext_sym_list
*extsym_iter
;
2054 struct ext_sym_list
*extsym_start
= NULL
;
2056 while ((opt
= getopt(argc
, argv
, "i:I:e:cmsSo:awM:K:")) != -1) {
2059 kernel_read
= optarg
;
2062 module_read
= optarg
;
2063 external_module
= 1;
2069 external_module
= 1;
2071 NOFAIL(malloc(sizeof(*extsym_iter
)));
2072 extsym_iter
->next
= extsym_start
;
2073 extsym_iter
->file
= optarg
;
2074 extsym_start
= extsym_iter
;
2080 dump_write
= optarg
;
2086 vmlinux_section_warnings
= 0;
2089 sec_mismatch_verbose
= 0;
2092 warn_unresolved
= 1;
2095 markers_write
= optarg
;
2098 markers_read
= optarg
;
2106 read_dump(kernel_read
, 1);
2108 read_dump(module_read
, 0);
2109 while (extsym_start
) {
2110 read_dump(extsym_start
->file
, 0);
2111 extsym_iter
= extsym_start
->next
;
2113 extsym_start
= extsym_iter
;
2116 while (optind
< argc
)
2117 read_symbols(argv
[optind
++]);
2119 for (mod
= modules
; mod
; mod
= mod
->next
) {
2127 for (mod
= modules
; mod
; mod
= mod
->next
) {
2128 char fname
[strlen(mod
->name
) + 10];
2135 add_header(&buf
, mod
);
2136 err
|= add_versions(&buf
, mod
);
2137 add_depends(&buf
, mod
, modules
);
2138 add_moddevtable(&buf
, mod
);
2139 add_srcversion(&buf
, mod
);
2141 sprintf(fname
, "%s.mod.c", mod
->name
);
2142 write_if_changed(&buf
, fname
);
2146 write_dump(dump_write
);
2147 if (sec_mismatch_count
&& !sec_mismatch_verbose
)
2148 warn("modpost: Found %d section mismatch(es).\n"
2149 "To see full details build your kernel with:\n"
2150 "'make CONFIG_DEBUG_SECTION_MISMATCH=y'\n",
2151 sec_mismatch_count
);
2154 read_markers(markers_read
);
2157 write_markers(markers_write
);