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 mod = new_module(NOFAIL(strdup(modname)));
1992 if (is_vmlinux(modname)) {
1998 add_marker(mod, marker, fmt);
2002 fatal("parse error in markers list file\n");
2005 static int compare_strings(const void *a, const void *b)
2007 return strcmp(*(const char **) a, *(const char **) b);
2010 static void write_markers(const char *fname)
2012 struct buffer buf = { };
2016 for (mod = modules; mod; mod = mod->next)
2017 if ((!external_module || !mod->skip) && mod->markers != NULL) {
2019 * Sort the strings so we can skip duplicates when
2020 * we write them out.
2022 qsort(mod->markers, mod->nmarkers,
2023 sizeof mod->markers[0], &compare_strings);
2024 for (i = 0; i < mod->nmarkers; ++i) {
2025 char *line = mod->markers[i];
2026 buf_write(&buf, line, strlen(line));
2027 while (i + 1 < mod->nmarkers &&
2028 !strcmp(mod->markers[i],
2029 mod->markers[i + 1]))
2030 free(mod->markers[i++]);
2031 free(mod->markers[i]);
2034 mod->markers = NULL;
2037 write_if_changed(&buf, fname);
2040 struct ext_sym_list {
2041 struct ext_sym_list *next;
2045 int main(int argc, char **argv)
2048 struct buffer buf = { };
2049 char *kernel_read = NULL, *module_read = NULL;
2050 char *dump_write = NULL;
2051 char *markers_read = NULL;
2052 char *markers_write = NULL;
2055 struct ext_sym_list *extsym_iter;
2056 struct ext_sym_list *extsym_start = NULL;
2058 while ((opt = getopt(argc, argv, "i:I:e:cmsSo:awM:K:")) != -1) {
2061 kernel_read = optarg;
2064 module_read = optarg;
2065 external_module = 1;
2071 external_module = 1;
2073 NOFAIL(malloc(sizeof(*extsym_iter)));
2074 extsym_iter->next = extsym_start;
2075 extsym_iter->file = optarg;
2076 extsym_start = extsym_iter;
2082 dump_write = optarg;
2088 vmlinux_section_warnings = 0;
2091 sec_mismatch_verbose = 0;
2094 warn_unresolved = 1;
2097 markers_write = optarg;
2100 markers_read = optarg;
2108 read_dump(kernel_read, 1);
2110 read_dump(module_read, 0);
2111 while (extsym_start) {
2112 read_dump(extsym_start->file, 0);
2113 extsym_iter = extsym_start->next;
2115 extsym_start = extsym_iter;
2118 while (optind < argc)
2119 read_symbols(argv[optind++]);
2121 for (mod = modules; mod; mod = mod->next) {
2129 for (mod = modules; mod; mod = mod->next) {
2130 char fname[strlen(mod->name) + 10];
2137 add_header(&buf, mod);
2138 err |= add_versions(&buf, mod);
2139 add_depends(&buf, mod, modules);
2140 add_moddevtable(&buf, mod);
2141 add_srcversion(&buf, mod);
2143 sprintf(fname, "%s.mod.c", mod->name);
2144 write_if_changed(&buf, fname);
2148 write_dump(dump_write);
2149 if (sec_mismatch_count && !sec_mismatch_verbose)
2150 warn("modpost: Found %d section mismatch(es).\n"
2151 "To see full details build your kernel with:\n"
2152 "'make CONFIG_DEBUG_SECTION_MISMATCH=y'\n",
2153 sec_mismatch_count);
2156 read_markers(markers_read);
2159 write_markers(markers_write);