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 ...
22 #include "../../include/generated/autoconf.h"
23 #include "../../include/linux/license.h"
24 #include "../../include/linux/export.h"
26 /* Are we using CONFIG_MODVERSIONS? */
27 static int modversions = 0;
28 /* Warn about undefined symbols? (do so if we have vmlinux) */
29 static int have_vmlinux = 0;
30 /* Is CONFIG_MODULE_SRCVERSION_ALL set? */
31 static int all_versions = 0;
32 /* If we are modposting external module set to 1 */
33 static int external_module = 0;
34 /* Warn about section mismatch in vmlinux if set to 1 */
35 static int vmlinux_section_warnings = 1;
36 /* Only warn about unresolved symbols */
37 static int warn_unresolved = 0;
38 /* How a symbol is exported */
39 static int sec_mismatch_count = 0;
40 static int sec_mismatch_verbose = 1;
41 static int sec_mismatch_fatal = 0;
42 /* ignore missing files */
43 static int ignore_missing_files;
46 export_plain, export_unused, export_gpl,
47 export_unused_gpl, export_gpl_future, export_unknown
50 /* In kernel, this size is defined in linux/module.h;
51 * here we use Elf_Addr instead of long for covering cross-compile
54 #define MODULE_NAME_LEN (64 - sizeof(Elf_Addr))
56 #define PRINTF __attribute__ ((format (printf, 1, 2)))
58 PRINTF void fatal(const char *fmt, ...)
62 fprintf(stderr, "FATAL: ");
64 va_start(arglist, fmt);
65 vfprintf(stderr, fmt, arglist);
71 PRINTF void warn(const char *fmt, ...)
75 fprintf(stderr, "WARNING: ");
77 va_start(arglist, fmt);
78 vfprintf(stderr, fmt, arglist);
82 PRINTF void merror(const char *fmt, ...)
86 fprintf(stderr, "ERROR: ");
88 va_start(arglist, fmt);
89 vfprintf(stderr, fmt, arglist);
93 static inline bool strends(const char *str, const char *postfix)
95 if (strlen(str) < strlen(postfix))
98 return strcmp(str + strlen(str) - strlen(postfix), postfix) == 0;
101 static int is_vmlinux(const char *modname)
105 myname = strrchr(modname, '/');
111 return (strcmp(myname, "vmlinux") == 0) ||
112 (strcmp(myname, "vmlinux.o") == 0);
115 void *do_nofail(void *ptr, const char *expr)
118 fatal("modpost: Memory allocation failure: %s.\n", expr);
123 /* A list of all modules we processed */
124 static struct module *modules;
126 static struct module *find_module(char *modname)
130 for (mod = modules; mod; mod = mod->next)
131 if (strcmp(mod->name, modname) == 0)
136 static struct module *new_module(const char *modname)
141 mod = NOFAIL(malloc(sizeof(*mod)));
142 memset(mod, 0, sizeof(*mod));
143 p = NOFAIL(strdup(modname));
145 /* strip trailing .o */
146 if (strends(p, ".o")) {
147 p[strlen(p) - 2] = '\0';
153 mod->gpl_compatible = -1;
160 /* A hash of all exported symbols,
161 * struct symbol is also used for lists of unresolved symbols */
163 #define SYMBOL_HASH_SIZE 1024
167 struct module *module;
171 unsigned int vmlinux:1; /* 1 if symbol is defined in vmlinux */
172 unsigned int kernel:1; /* 1 if symbol is from kernel
173 * (only for external modules) **/
174 unsigned int preloaded:1; /* 1 if symbol from Module.symvers, or crc */
175 enum export export; /* Type of export */
179 static struct symbol *symbolhash[SYMBOL_HASH_SIZE];
181 /* This is based on the hash agorithm from gdbm, via tdb */
182 static inline unsigned int tdb_hash(const char *name)
184 unsigned value; /* Used to compute the hash value. */
185 unsigned i; /* Used to cycle through random values. */
187 /* Set the initial value from the key size. */
188 for (value = 0x238F13AF * strlen(name), i = 0; name[i]; i++)
189 value = (value + (((unsigned char *)name)[i] << (i*5 % 24)));
191 return (1103515243 * value + 12345);
195 * Allocate a new symbols for use in the hash of exported symbols or
196 * the list of unresolved symbols per module
198 static struct symbol *alloc_symbol(const char *name, unsigned int weak,
201 struct symbol *s = NOFAIL(malloc(sizeof(*s) + strlen(name) + 1));
203 memset(s, 0, sizeof(*s));
204 strcpy(s->name, name);
210 /* For the hash of exported symbols */
211 static struct symbol *new_symbol(const char *name, struct module *module,
217 hash = tdb_hash(name) % SYMBOL_HASH_SIZE;
218 new = symbolhash[hash] = alloc_symbol(name, 0, symbolhash[hash]);
219 new->module = module;
220 new->export = export;
224 static struct symbol *find_symbol(const char *name)
228 /* For our purposes, .foo matches foo. PPC64 needs this. */
232 for (s = symbolhash[tdb_hash(name) % SYMBOL_HASH_SIZE]; s; s = s->next) {
233 if (strcmp(s->name, name) == 0)
239 static const struct {
243 { .str = "EXPORT_SYMBOL", .export = export_plain },
244 { .str = "EXPORT_UNUSED_SYMBOL", .export = export_unused },
245 { .str = "EXPORT_SYMBOL_GPL", .export = export_gpl },
246 { .str = "EXPORT_UNUSED_SYMBOL_GPL", .export = export_unused_gpl },
247 { .str = "EXPORT_SYMBOL_GPL_FUTURE", .export = export_gpl_future },
248 { .str = "(unknown)", .export = export_unknown },
252 static const char *export_str(enum export ex)
254 return export_list[ex].str;
257 static enum export export_no(const char *s)
262 return export_unknown;
263 for (i = 0; export_list[i].export != export_unknown; i++) {
264 if (strcmp(export_list[i].str, s) == 0)
265 return export_list[i].export;
267 return export_unknown;
270 static const char *sech_name(struct elf_info *elf, Elf_Shdr *sechdr)
272 return (void *)elf->hdr +
273 elf->sechdrs[elf->secindex_strings].sh_offset +
277 static const char *sec_name(struct elf_info *elf, int secindex)
279 return sech_name(elf, &elf->sechdrs[secindex]);
282 #define strstarts(str, prefix) (strncmp(str, prefix, strlen(prefix)) == 0)
284 static enum export export_from_secname(struct elf_info *elf, unsigned int sec)
286 const char *secname = sec_name(elf, sec);
288 if (strstarts(secname, "___ksymtab+"))
290 else if (strstarts(secname, "___ksymtab_unused+"))
291 return export_unused;
292 else if (strstarts(secname, "___ksymtab_gpl+"))
294 else if (strstarts(secname, "___ksymtab_unused_gpl+"))
295 return export_unused_gpl;
296 else if (strstarts(secname, "___ksymtab_gpl_future+"))
297 return export_gpl_future;
299 return export_unknown;
302 static enum export export_from_sec(struct elf_info *elf, unsigned int sec)
304 if (sec == elf->export_sec)
306 else if (sec == elf->export_unused_sec)
307 return export_unused;
308 else if (sec == elf->export_gpl_sec)
310 else if (sec == elf->export_unused_gpl_sec)
311 return export_unused_gpl;
312 else if (sec == elf->export_gpl_future_sec)
313 return export_gpl_future;
315 return export_unknown;
319 * Add an exported symbol - it may have already been added without a
320 * CRC, in this case just update the CRC
322 static struct symbol *sym_add_exported(const char *name, struct module *mod,
325 struct symbol *s = find_symbol(name);
328 s = new_symbol(name, mod, export);
331 warn("%s: '%s' exported twice. Previous export "
332 "was in %s%s\n", mod->name, name,
334 is_vmlinux(s->module->name) ?"":".ko");
336 /* In case Module.symvers was out of date */
341 s->vmlinux = is_vmlinux(mod->name);
347 static void sym_update_crc(const char *name, struct module *mod,
348 unsigned int crc, enum export export)
350 struct symbol *s = find_symbol(name);
353 s = new_symbol(name, mod, export);
354 /* Don't complain when we find it later. */
361 void *grab_file(const char *filename, unsigned long *size)
364 void *map = MAP_FAILED;
367 fd = open(filename, O_RDONLY);
374 map = mmap(NULL, *size, PROT_READ|PROT_WRITE, MAP_PRIVATE, fd, 0);
378 if (map == MAP_FAILED)
384 * Return a copy of the next line in a mmap'ed file.
385 * spaces in the beginning of the line is trimmed away.
386 * Return a pointer to a static buffer.
388 char *get_next_line(unsigned long *pos, void *file, unsigned long size)
390 static char line[4096];
393 signed char *p = (signed char *)file + *pos;
396 for (; *pos < size ; (*pos)++) {
397 if (skip && isspace(*p)) {
402 if (*p != '\n' && (*pos < size)) {
406 break; /* Too long, stop */
417 void release_file(void *file, unsigned long size)
422 static int parse_elf(struct elf_info *info, const char *filename)
428 const char *secstrings;
429 unsigned int symtab_idx = ~0U, symtab_shndx_idx = ~0U;
431 hdr = grab_file(filename, &info->size);
433 if (ignore_missing_files) {
434 fprintf(stderr, "%s: %s (ignored)\n", filename,
442 if (info->size < sizeof(*hdr)) {
443 /* file too small, assume this is an empty .o file */
446 /* Is this a valid ELF file? */
447 if ((hdr->e_ident[EI_MAG0] != ELFMAG0) ||
448 (hdr->e_ident[EI_MAG1] != ELFMAG1) ||
449 (hdr->e_ident[EI_MAG2] != ELFMAG2) ||
450 (hdr->e_ident[EI_MAG3] != ELFMAG3)) {
451 /* Not an ELF file - silently ignore it */
454 /* Fix endianness in ELF header */
455 hdr->e_type = TO_NATIVE(hdr->e_type);
456 hdr->e_machine = TO_NATIVE(hdr->e_machine);
457 hdr->e_version = TO_NATIVE(hdr->e_version);
458 hdr->e_entry = TO_NATIVE(hdr->e_entry);
459 hdr->e_phoff = TO_NATIVE(hdr->e_phoff);
460 hdr->e_shoff = TO_NATIVE(hdr->e_shoff);
461 hdr->e_flags = TO_NATIVE(hdr->e_flags);
462 hdr->e_ehsize = TO_NATIVE(hdr->e_ehsize);
463 hdr->e_phentsize = TO_NATIVE(hdr->e_phentsize);
464 hdr->e_phnum = TO_NATIVE(hdr->e_phnum);
465 hdr->e_shentsize = TO_NATIVE(hdr->e_shentsize);
466 hdr->e_shnum = TO_NATIVE(hdr->e_shnum);
467 hdr->e_shstrndx = TO_NATIVE(hdr->e_shstrndx);
468 sechdrs = (void *)hdr + hdr->e_shoff;
469 info->sechdrs = sechdrs;
471 /* Check if file offset is correct */
472 if (hdr->e_shoff > info->size) {
473 fatal("section header offset=%lu in file '%s' is bigger than "
474 "filesize=%lu\n", (unsigned long)hdr->e_shoff,
475 filename, info->size);
479 if (hdr->e_shnum == SHN_UNDEF) {
481 * There are more than 64k sections,
482 * read count from .sh_size.
484 info->num_sections = TO_NATIVE(sechdrs[0].sh_size);
487 info->num_sections = hdr->e_shnum;
489 if (hdr->e_shstrndx == SHN_XINDEX) {
490 info->secindex_strings = TO_NATIVE(sechdrs[0].sh_link);
493 info->secindex_strings = hdr->e_shstrndx;
496 /* Fix endianness in section headers */
497 for (i = 0; i < info->num_sections; i++) {
498 sechdrs[i].sh_name = TO_NATIVE(sechdrs[i].sh_name);
499 sechdrs[i].sh_type = TO_NATIVE(sechdrs[i].sh_type);
500 sechdrs[i].sh_flags = TO_NATIVE(sechdrs[i].sh_flags);
501 sechdrs[i].sh_addr = TO_NATIVE(sechdrs[i].sh_addr);
502 sechdrs[i].sh_offset = TO_NATIVE(sechdrs[i].sh_offset);
503 sechdrs[i].sh_size = TO_NATIVE(sechdrs[i].sh_size);
504 sechdrs[i].sh_link = TO_NATIVE(sechdrs[i].sh_link);
505 sechdrs[i].sh_info = TO_NATIVE(sechdrs[i].sh_info);
506 sechdrs[i].sh_addralign = TO_NATIVE(sechdrs[i].sh_addralign);
507 sechdrs[i].sh_entsize = TO_NATIVE(sechdrs[i].sh_entsize);
509 /* Find symbol table. */
510 secstrings = (void *)hdr + sechdrs[info->secindex_strings].sh_offset;
511 for (i = 1; i < info->num_sections; i++) {
513 int nobits = sechdrs[i].sh_type == SHT_NOBITS;
515 if (!nobits && sechdrs[i].sh_offset > info->size) {
516 fatal("%s is truncated. sechdrs[i].sh_offset=%lu > "
517 "sizeof(*hrd)=%zu\n", filename,
518 (unsigned long)sechdrs[i].sh_offset,
522 secname = secstrings + sechdrs[i].sh_name;
523 if (strcmp(secname, ".modinfo") == 0) {
525 fatal("%s has NOBITS .modinfo\n", filename);
526 info->modinfo = (void *)hdr + sechdrs[i].sh_offset;
527 info->modinfo_len = sechdrs[i].sh_size;
528 } else if (strcmp(secname, "__ksymtab") == 0)
529 info->export_sec = i;
530 else if (strcmp(secname, "__ksymtab_unused") == 0)
531 info->export_unused_sec = i;
532 else if (strcmp(secname, "__ksymtab_gpl") == 0)
533 info->export_gpl_sec = i;
534 else if (strcmp(secname, "__ksymtab_unused_gpl") == 0)
535 info->export_unused_gpl_sec = i;
536 else if (strcmp(secname, "__ksymtab_gpl_future") == 0)
537 info->export_gpl_future_sec = i;
539 if (sechdrs[i].sh_type == SHT_SYMTAB) {
540 unsigned int sh_link_idx;
542 info->symtab_start = (void *)hdr +
543 sechdrs[i].sh_offset;
544 info->symtab_stop = (void *)hdr +
545 sechdrs[i].sh_offset + sechdrs[i].sh_size;
546 sh_link_idx = sechdrs[i].sh_link;
547 info->strtab = (void *)hdr +
548 sechdrs[sh_link_idx].sh_offset;
551 /* 32bit section no. table? ("more than 64k sections") */
552 if (sechdrs[i].sh_type == SHT_SYMTAB_SHNDX) {
553 symtab_shndx_idx = i;
554 info->symtab_shndx_start = (void *)hdr +
555 sechdrs[i].sh_offset;
556 info->symtab_shndx_stop = (void *)hdr +
557 sechdrs[i].sh_offset + sechdrs[i].sh_size;
560 if (!info->symtab_start)
561 fatal("%s has no symtab?\n", filename);
563 /* Fix endianness in symbols */
564 for (sym = info->symtab_start; sym < info->symtab_stop; sym++) {
565 sym->st_shndx = TO_NATIVE(sym->st_shndx);
566 sym->st_name = TO_NATIVE(sym->st_name);
567 sym->st_value = TO_NATIVE(sym->st_value);
568 sym->st_size = TO_NATIVE(sym->st_size);
571 if (symtab_shndx_idx != ~0U) {
573 if (symtab_idx != sechdrs[symtab_shndx_idx].sh_link)
574 fatal("%s: SYMTAB_SHNDX has bad sh_link: %u!=%u\n",
575 filename, sechdrs[symtab_shndx_idx].sh_link,
578 for (p = info->symtab_shndx_start; p < info->symtab_shndx_stop;
586 static void parse_elf_finish(struct elf_info *info)
588 release_file(info->hdr, info->size);
591 static int ignore_undef_symbol(struct elf_info *info, const char *symname)
593 /* ignore __this_module, it will be resolved shortly */
594 if (strcmp(symname, VMLINUX_SYMBOL_STR(__this_module)) == 0)
596 /* ignore global offset table */
597 if (strcmp(symname, "_GLOBAL_OFFSET_TABLE_") == 0)
599 if (info->hdr->e_machine == EM_PPC)
600 /* Special register function linked on all modules during final link of .ko */
601 if (strncmp(symname, "_restgpr_", sizeof("_restgpr_") - 1) == 0 ||
602 strncmp(symname, "_savegpr_", sizeof("_savegpr_") - 1) == 0 ||
603 strncmp(symname, "_rest32gpr_", sizeof("_rest32gpr_") - 1) == 0 ||
604 strncmp(symname, "_save32gpr_", sizeof("_save32gpr_") - 1) == 0 ||
605 strncmp(symname, "_restvr_", sizeof("_restvr_") - 1) == 0 ||
606 strncmp(symname, "_savevr_", sizeof("_savevr_") - 1) == 0)
608 if (info->hdr->e_machine == EM_PPC64)
609 /* Special register function linked on all modules during final link of .ko */
610 if (strncmp(symname, "_restgpr0_", sizeof("_restgpr0_") - 1) == 0 ||
611 strncmp(symname, "_savegpr0_", sizeof("_savegpr0_") - 1) == 0 ||
612 strncmp(symname, "_restvr_", sizeof("_restvr_") - 1) == 0 ||
613 strncmp(symname, "_savevr_", sizeof("_savevr_") - 1) == 0 ||
614 strcmp(symname, ".TOC.") == 0)
616 /* Do not ignore this symbol */
620 #define CRC_PFX VMLINUX_SYMBOL_STR(__crc_)
621 #define KSYMTAB_PFX VMLINUX_SYMBOL_STR(__ksymtab_)
623 static void handle_modversions(struct module *mod, struct elf_info *info,
624 Elf_Sym *sym, const char *symname)
630 if ((!is_vmlinux(mod->name) || mod->is_dot_o) &&
631 strncmp(symname, "__ksymtab", 9) == 0)
632 export = export_from_secname(info, get_secindex(info, sym));
634 export = export_from_sec(info, get_secindex(info, sym));
637 if (strncmp(symname, CRC_PFX, strlen(CRC_PFX)) == 0) {
639 crc = (unsigned int) sym->st_value;
640 if (sym->st_shndx != SHN_UNDEF && sym->st_shndx != SHN_ABS) {
643 /* symbol points to the CRC in the ELF object */
644 crcp = (void *)info->hdr + sym->st_value +
645 info->sechdrs[sym->st_shndx].sh_offset -
646 (info->hdr->e_type != ET_REL ?
647 info->sechdrs[sym->st_shndx].sh_addr : 0);
648 crc = TO_NATIVE(*crcp);
650 sym_update_crc(symname + strlen(CRC_PFX), mod, crc,
654 switch (sym->st_shndx) {
656 if (!strncmp(symname, "__gnu_lto_", sizeof("__gnu_lto_")-1)) {
657 /* Should warn here, but modpost runs before the linker */
659 warn("\"%s\" [%s] is COMMON symbol\n", symname, mod->name);
662 /* undefined symbol */
663 if (ELF_ST_BIND(sym->st_info) != STB_GLOBAL &&
664 ELF_ST_BIND(sym->st_info) != STB_WEAK)
666 if (ignore_undef_symbol(info, symname))
668 /* cope with newer glibc (2.3.4 or higher) STT_ definition in elf.h */
669 #if defined(STT_REGISTER) || defined(STT_SPARC_REGISTER)
670 /* add compatibility with older glibc */
671 #ifndef STT_SPARC_REGISTER
672 #define STT_SPARC_REGISTER STT_REGISTER
674 if (info->hdr->e_machine == EM_SPARC ||
675 info->hdr->e_machine == EM_SPARCV9) {
676 /* Ignore register directives. */
677 if (ELF_ST_TYPE(sym->st_info) == STT_SPARC_REGISTER)
679 if (symname[0] == '.') {
680 char *munged = NOFAIL(strdup(symname));
682 munged[1] = toupper(munged[1]);
688 #ifdef CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX
689 if (symname[0] != '_')
695 const char *e = is_vmlinux(mod->name) ?"":".ko";
696 warn("EXPORT symbol \"%s\" [%s%s] version generation failed, symbol will not be versioned.\n", symname + strlen(CRC_PFX), mod->name, e);
698 mod->unres = alloc_symbol(symname,
699 ELF_ST_BIND(sym->st_info) == STB_WEAK,
703 /* All exported symbols */
704 if (strncmp(symname, KSYMTAB_PFX, strlen(KSYMTAB_PFX)) == 0) {
705 sym_add_exported(symname + strlen(KSYMTAB_PFX), mod,
708 if (strcmp(symname, VMLINUX_SYMBOL_STR(init_module)) == 0)
710 if (strcmp(symname, VMLINUX_SYMBOL_STR(cleanup_module)) == 0)
711 mod->has_cleanup = 1;
717 * Parse tag=value strings from .modinfo section
719 static char *next_string(char *string, unsigned long *secsize)
721 /* Skip non-zero chars */
724 if ((*secsize)-- <= 1)
728 /* Skip any zero padding. */
731 if ((*secsize)-- <= 1)
737 static char *get_next_modinfo(void *modinfo, unsigned long modinfo_len,
738 const char *tag, char *info)
741 unsigned int taglen = strlen(tag);
742 unsigned long size = modinfo_len;
745 size -= info - (char *)modinfo;
746 modinfo = next_string(info, &size);
749 for (p = modinfo; p; p = next_string(p, &size)) {
750 if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=')
751 return p + taglen + 1;
756 static char *get_modinfo(void *modinfo, unsigned long modinfo_len,
760 return get_next_modinfo(modinfo, modinfo_len, tag, NULL);
764 * Test if string s ends in string sub
767 static int strrcmp(const char *s, const char *sub)
775 sublen = strlen(sub);
777 if ((slen == 0) || (sublen == 0))
783 return memcmp(s + slen - sublen, sub, sublen);
786 static const char *sym_name(struct elf_info *elf, Elf_Sym *sym)
789 return elf->strtab + sym->st_name;
794 /* The pattern is an array of simple patterns.
795 * "foo" will match an exact string equal to "foo"
796 * "*foo" will match a string that ends with "foo"
797 * "foo*" will match a string that begins with "foo"
798 * "*foo*" will match a string that contains "foo"
800 static int match(const char *sym, const char * const pat[])
805 const char *endp = p + strlen(p) - 1;
808 if (*p == '*' && *endp == '*') {
809 char *here, *bare = strndup(p + 1, strlen(p) - 2);
811 here = strstr(sym, bare);
817 else if (*p == '*') {
818 if (strrcmp(sym, p + 1) == 0)
822 else if (*endp == '*') {
823 if (strncmp(sym, p, strlen(p) - 1) == 0)
828 if (strcmp(p, sym) == 0)
836 /* sections that we do not want to do full section mismatch check on */
837 static const char *const section_white_list[] =
841 ".cranges", /* sh64 */
842 ".zdebug*", /* Compressed debug sections. */
843 ".GCC-command-line", /* mn10300 */
844 ".GCC.command.line", /* record-gcc-switches, non mn10300 */
845 ".mdebug*", /* alpha, score, mips etc. */
846 ".pdr", /* alpha, score, mips etc. */
851 ".xt.prop", /* xtensa */
852 ".xt.lit", /* xtensa */
853 ".arcextmap*", /* arc */
854 ".gnu.linkonce.arcext*", /* arc : modules */
855 ".cmem*", /* EZchip */
856 ".fmt_slot*", /* EZchip */
863 * This is used to find sections missing the SHF_ALLOC flag.
864 * The cause of this is often a section specified in assembler
865 * without "ax" / "aw".
867 static void check_section(const char *modname, struct elf_info *elf,
870 const char *sec = sech_name(elf, sechdr);
872 if (sechdr->sh_type == SHT_PROGBITS &&
873 !(sechdr->sh_flags & SHF_ALLOC) &&
874 !match(sec, section_white_list)) {
875 warn("%s (%s): unexpected non-allocatable section.\n"
876 "Did you forget to use \"ax\"/\"aw\" in a .S file?\n"
877 "Note that for example <linux/init.h> contains\n"
878 "section definitions for use in .S files.\n\n",
885 #define ALL_INIT_DATA_SECTIONS \
886 ".init.setup", ".init.rodata", ".meminit.rodata", \
887 ".init.data", ".meminit.data"
888 #define ALL_EXIT_DATA_SECTIONS \
889 ".exit.data", ".memexit.data"
891 #define ALL_INIT_TEXT_SECTIONS \
892 ".init.text", ".meminit.text"
893 #define ALL_EXIT_TEXT_SECTIONS \
894 ".exit.text", ".memexit.text"
896 #define ALL_PCI_INIT_SECTIONS \
897 ".pci_fixup_early", ".pci_fixup_header", ".pci_fixup_final", \
898 ".pci_fixup_enable", ".pci_fixup_resume", \
899 ".pci_fixup_resume_early", ".pci_fixup_suspend"
901 #define ALL_XXXINIT_SECTIONS MEM_INIT_SECTIONS
902 #define ALL_XXXEXIT_SECTIONS MEM_EXIT_SECTIONS
904 #define ALL_INIT_SECTIONS INIT_SECTIONS, ALL_XXXINIT_SECTIONS
905 #define ALL_EXIT_SECTIONS EXIT_SECTIONS, ALL_XXXEXIT_SECTIONS
907 #define DATA_SECTIONS ".data", ".data.rel"
908 #define TEXT_SECTIONS ".text", ".text.unlikely", ".sched.text", \
909 ".kprobes.text", ".cpuidle.text"
910 #define OTHER_TEXT_SECTIONS ".ref.text", ".head.text", ".spinlock.text", \
911 ".fixup", ".entry.text", ".exception.text", ".text.*", \
914 #define INIT_SECTIONS ".init.*"
915 #define MEM_INIT_SECTIONS ".meminit.*"
917 #define EXIT_SECTIONS ".exit.*"
918 #define MEM_EXIT_SECTIONS ".memexit.*"
920 #define ALL_TEXT_SECTIONS ALL_INIT_TEXT_SECTIONS, ALL_EXIT_TEXT_SECTIONS, \
921 TEXT_SECTIONS, OTHER_TEXT_SECTIONS
923 /* init data sections */
924 static const char *const init_data_sections[] =
925 { ALL_INIT_DATA_SECTIONS, NULL };
927 /* all init sections */
928 static const char *const init_sections[] = { ALL_INIT_SECTIONS, NULL };
930 /* All init and exit sections (code + data) */
931 static const char *const init_exit_sections[] =
932 {ALL_INIT_SECTIONS, ALL_EXIT_SECTIONS, NULL };
934 /* all text sections */
935 static const char *const text_sections[] = { ALL_TEXT_SECTIONS, NULL };
938 static const char *const data_sections[] = { DATA_SECTIONS, NULL };
941 /* symbols in .data that may refer to init/exit sections */
942 #define DEFAULT_SYMBOL_WHITE_LIST \
944 "*_template", /* scsi uses *_template a lot */ \
945 "*_timer", /* arm uses ops structures named _timer a lot */ \
946 "*_sht", /* scsi also used *_sht to some extent */ \
952 static const char *const head_sections[] = { ".head.text*", NULL };
953 static const char *const linker_symbols[] =
954 { "__init_begin", "_sinittext", "_einittext", NULL };
955 static const char *const optim_symbols[] = { "*.constprop.*", NULL };
962 XXXINIT_TO_SOME_INIT,
963 XXXEXIT_TO_SOME_EXIT,
964 ANY_INIT_TO_ANY_EXIT,
965 ANY_EXIT_TO_ANY_INIT,
971 * Describe how to match sections on different criterias:
973 * @fromsec: Array of sections to be matched.
975 * @bad_tosec: Relocations applied to a section in @fromsec to a section in
976 * this array is forbidden (black-list). Can be empty.
978 * @good_tosec: Relocations applied to a section in @fromsec must be
979 * targetting sections in this array (white-list). Can be empty.
981 * @mismatch: Type of mismatch.
983 * @symbol_white_list: Do not match a relocation to a symbol in this list
984 * even if it is targetting a section in @bad_to_sec.
986 * @handler: Specific handler to call when a match is found. If NULL,
987 * default_mismatch_handler() will be called.
990 struct sectioncheck {
991 const char *fromsec[20];
992 const char *bad_tosec[20];
993 const char *good_tosec[20];
994 enum mismatch mismatch;
995 const char *symbol_white_list[20];
996 void (*handler)(const char *modname, struct elf_info *elf,
997 const struct sectioncheck* const mismatch,
998 Elf_Rela *r, Elf_Sym *sym, const char *fromsec);
1002 static void extable_mismatch_handler(const char *modname, struct elf_info *elf,
1003 const struct sectioncheck* const mismatch,
1004 Elf_Rela *r, Elf_Sym *sym,
1005 const char *fromsec);
1007 static const struct sectioncheck sectioncheck[] = {
1008 /* Do not reference init/exit code/data from
1009 * normal code and data
1012 .fromsec = { TEXT_SECTIONS, NULL },
1013 .bad_tosec = { ALL_INIT_SECTIONS, NULL },
1014 .mismatch = TEXT_TO_ANY_INIT,
1015 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
1018 .fromsec = { DATA_SECTIONS, NULL },
1019 .bad_tosec = { ALL_XXXINIT_SECTIONS, NULL },
1020 .mismatch = DATA_TO_ANY_INIT,
1021 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
1024 .fromsec = { DATA_SECTIONS, NULL },
1025 .bad_tosec = { INIT_SECTIONS, NULL },
1026 .mismatch = DATA_TO_ANY_INIT,
1027 .symbol_white_list = {
1028 "*_template", "*_timer", "*_sht", "*_ops",
1029 "*_probe", "*_probe_one", "*_console", NULL
1033 .fromsec = { TEXT_SECTIONS, NULL },
1034 .bad_tosec = { ALL_EXIT_SECTIONS, NULL },
1035 .mismatch = TEXT_TO_ANY_EXIT,
1036 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
1039 .fromsec = { DATA_SECTIONS, NULL },
1040 .bad_tosec = { ALL_EXIT_SECTIONS, NULL },
1041 .mismatch = DATA_TO_ANY_EXIT,
1042 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
1044 /* Do not reference init code/data from meminit code/data */
1046 .fromsec = { ALL_XXXINIT_SECTIONS, NULL },
1047 .bad_tosec = { INIT_SECTIONS, NULL },
1048 .mismatch = XXXINIT_TO_SOME_INIT,
1049 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
1051 /* Do not reference exit code/data from memexit code/data */
1053 .fromsec = { ALL_XXXEXIT_SECTIONS, NULL },
1054 .bad_tosec = { EXIT_SECTIONS, NULL },
1055 .mismatch = XXXEXIT_TO_SOME_EXIT,
1056 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
1058 /* Do not use exit code/data from init code */
1060 .fromsec = { ALL_INIT_SECTIONS, NULL },
1061 .bad_tosec = { ALL_EXIT_SECTIONS, NULL },
1062 .mismatch = ANY_INIT_TO_ANY_EXIT,
1063 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
1065 /* Do not use init code/data from exit code */
1067 .fromsec = { ALL_EXIT_SECTIONS, NULL },
1068 .bad_tosec = { ALL_INIT_SECTIONS, NULL },
1069 .mismatch = ANY_EXIT_TO_ANY_INIT,
1070 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
1073 .fromsec = { ALL_PCI_INIT_SECTIONS, NULL },
1074 .bad_tosec = { INIT_SECTIONS, NULL },
1075 .mismatch = ANY_INIT_TO_ANY_EXIT,
1076 .symbol_white_list = { NULL },
1078 /* Do not export init/exit functions or data */
1080 .fromsec = { "___ksymtab*", NULL },
1081 .bad_tosec = { INIT_SECTIONS, EXIT_SECTIONS, NULL },
1082 .mismatch = EXPORT_TO_INIT_EXIT,
1083 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
1086 .fromsec = { "__ex_table", NULL },
1087 /* If you're adding any new black-listed sections in here, consider
1088 * adding a special 'printer' for them in scripts/check_extable.
1090 .bad_tosec = { ".altinstr_replacement", NULL },
1091 .good_tosec = {ALL_TEXT_SECTIONS , NULL},
1092 .mismatch = EXTABLE_TO_NON_TEXT,
1093 .handler = extable_mismatch_handler,
1097 static const struct sectioncheck *section_mismatch(
1098 const char *fromsec, const char *tosec)
1101 int elems = sizeof(sectioncheck) / sizeof(struct sectioncheck);
1102 const struct sectioncheck *check = §ioncheck[0];
1105 * The target section could be the SHT_NUL section when we're
1106 * handling relocations to un-resolved symbols, trying to match it
1107 * doesn't make much sense and causes build failures on parisc and
1108 * mn10300 architectures.
1113 for (i = 0; i < elems; i++) {
1114 if (match(fromsec, check->fromsec)) {
1115 if (check->bad_tosec[0] && match(tosec, check->bad_tosec))
1117 if (check->good_tosec[0] && !match(tosec, check->good_tosec))
1126 * Whitelist to allow certain references to pass with no warning.
1129 * If a module parameter is declared __initdata and permissions=0
1130 * then this is legal despite the warning generated.
1131 * We cannot see value of permissions here, so just ignore
1133 * The pattern is identified by:
1134 * tosec = .init.data
1139 * module_param_call() ops can refer to __init set function if permissions=0
1140 * The pattern is identified by:
1141 * tosec = .init.text
1143 * atsym = __param_ops_*
1146 * Many drivers utilise a *driver container with references to
1147 * add, remove, probe functions etc.
1148 * the pattern is identified by:
1149 * tosec = init or exit section
1150 * fromsec = data section
1151 * atsym = *driver, *_template, *_sht, *_ops, *_probe,
1152 * *probe_one, *_console, *_timer
1155 * Whitelist all references from .head.text to any init section
1158 * Some symbols belong to init section but still it is ok to reference
1159 * these from non-init sections as these symbols don't have any memory
1160 * allocated for them and symbol address and value are same. So even
1161 * if init section is freed, its ok to reference those symbols.
1162 * For ex. symbols marking the init section boundaries.
1163 * This pattern is identified by
1164 * refsymname = __init_begin, _sinittext, _einittext
1167 * GCC may optimize static inlines when fed constant arg(s) resulting
1168 * in functions like cpumask_empty() -- generating an associated symbol
1169 * cpumask_empty.constprop.3 that appears in the audit. If the const that
1170 * is passed in comes from __init, like say nmi_ipi_mask, we get a
1171 * meaningless section warning. May need to add isra symbols too...
1172 * This pattern is identified by
1173 * tosec = init section
1174 * fromsec = text section
1175 * refsymname = *.constprop.*
1178 * Hide section mismatch warnings for ELF local symbols. The goal
1179 * is to eliminate false positive modpost warnings caused by
1180 * compiler-generated ELF local symbol names such as ".LANCHOR1".
1181 * Autogenerated symbol names bypass modpost's "Pattern 2"
1182 * whitelisting, which relies on pattern-matching against symbol
1183 * names to work. (One situation where gcc can autogenerate ELF
1184 * local symbols is when "-fsection-anchors" is used.)
1186 static int secref_whitelist(const struct sectioncheck *mismatch,
1187 const char *fromsec, const char *fromsym,
1188 const char *tosec, const char *tosym)
1190 /* Check for pattern 1 */
1191 if (match(tosec, init_data_sections) &&
1192 match(fromsec, data_sections) &&
1193 (strncmp(fromsym, "__param", strlen("__param")) == 0))
1196 /* Check for pattern 1a */
1197 if (strcmp(tosec, ".init.text") == 0 &&
1198 match(fromsec, data_sections) &&
1199 (strncmp(fromsym, "__param_ops_", strlen("__param_ops_")) == 0))
1202 /* Check for pattern 2 */
1203 if (match(tosec, init_exit_sections) &&
1204 match(fromsec, data_sections) &&
1205 match(fromsym, mismatch->symbol_white_list))
1208 /* Check for pattern 3 */
1209 if (match(fromsec, head_sections) &&
1210 match(tosec, init_sections))
1213 /* Check for pattern 4 */
1214 if (match(tosym, linker_symbols))
1217 /* Check for pattern 5 */
1218 if (match(fromsec, text_sections) &&
1219 match(tosec, init_sections) &&
1220 match(fromsym, optim_symbols))
1223 /* Check for pattern 6 */
1224 if (strstarts(fromsym, ".L"))
1230 static inline int is_arm_mapping_symbol(const char *str)
1232 return str[0] == '$' &&
1233 (str[1] == 'a' || str[1] == 'd' || str[1] == 't' || str[1] == 'x')
1234 && (str[2] == '\0' || str[2] == '.');
1238 * If there's no name there, ignore it; likewise, ignore it if it's
1239 * one of the magic symbols emitted used by current ARM tools.
1241 * Otherwise if find_symbols_between() returns those symbols, they'll
1242 * fail the whitelist tests and cause lots of false alarms ... fixable
1243 * only by merging __exit and __init sections into __text, bloating
1244 * the kernel (which is especially evil on embedded platforms).
1246 static inline int is_valid_name(struct elf_info *elf, Elf_Sym *sym)
1248 const char *name = elf->strtab + sym->st_name;
1250 if (!name || !strlen(name))
1252 return !is_arm_mapping_symbol(name);
1256 * Find symbol based on relocation record info.
1257 * In some cases the symbol supplied is a valid symbol so
1258 * return refsym. If st_name != 0 we assume this is a valid symbol.
1259 * In other cases the symbol needs to be looked up in the symbol table
1260 * based on section and address.
1262 static Elf_Sym *find_elf_symbol(struct elf_info *elf, Elf64_Sword addr,
1266 Elf_Sym *near = NULL;
1267 Elf64_Sword distance = 20;
1269 unsigned int relsym_secindex;
1271 if (relsym->st_name != 0)
1275 * Strive to find a better symbol name, but the resulting name may not
1276 * match the symbol referenced in the original code.
1278 relsym_secindex = get_secindex(elf, relsym);
1279 for (sym = elf->symtab_start; sym < elf->symtab_stop; sym++) {
1280 if (get_secindex(elf, sym) != relsym_secindex)
1282 if (ELF_ST_TYPE(sym->st_info) == STT_SECTION)
1284 if (!is_valid_name(elf, sym))
1286 if (sym->st_value == addr)
1288 /* Find a symbol nearby - addr are maybe negative */
1289 d = sym->st_value - addr;
1291 d = addr - sym->st_value;
1297 /* We need a close match */
1305 * Find symbols before or equal addr and after addr - in the section sec.
1306 * If we find two symbols with equal offset prefer one with a valid name.
1307 * The ELF format may have a better way to detect what type of symbol
1308 * it is, but this works for now.
1310 static Elf_Sym *find_elf_symbol2(struct elf_info *elf, Elf_Addr addr,
1314 Elf_Sym *near = NULL;
1315 Elf_Addr distance = ~0;
1317 for (sym = elf->symtab_start; sym < elf->symtab_stop; sym++) {
1320 if (is_shndx_special(sym->st_shndx))
1322 symsec = sec_name(elf, get_secindex(elf, sym));
1323 if (strcmp(symsec, sec) != 0)
1325 if (!is_valid_name(elf, sym))
1327 if (sym->st_value <= addr) {
1328 if ((addr - sym->st_value) < distance) {
1329 distance = addr - sym->st_value;
1331 } else if ((addr - sym->st_value) == distance) {
1340 * Convert a section name to the function/data attribute
1341 * .init.text => __init
1342 * .memexitconst => __memconst
1345 * The memory of returned value has been allocated on a heap. The user of this
1346 * method should free it after usage.
1348 static char *sec2annotation(const char *s)
1350 if (match(s, init_exit_sections)) {
1351 char *p = NOFAIL(malloc(20));
1358 while (*s && *s != '.')
1363 if (strstr(s, "rodata") != NULL)
1364 strcat(p, "const ");
1365 else if (strstr(s, "data") != NULL)
1371 return NOFAIL(strdup(""));
1375 static int is_function(Elf_Sym *sym)
1378 return ELF_ST_TYPE(sym->st_info) == STT_FUNC;
1383 static void print_section_list(const char * const list[20])
1385 const char *const *s = list;
1388 fprintf(stderr, "%s", *s);
1391 fprintf(stderr, ", ");
1393 fprintf(stderr, "\n");
1396 static inline void get_pretty_name(int is_func, const char** name, const char** name_p)
1399 case 0: *name = "variable"; *name_p = ""; break;
1400 case 1: *name = "function"; *name_p = "()"; break;
1401 default: *name = "(unknown reference)"; *name_p = ""; break;
1406 * Print a warning about a section mismatch.
1407 * Try to find symbols near it so user can find it.
1408 * Check whitelist before warning - it may be a false positive.
1410 static void report_sec_mismatch(const char *modname,
1411 const struct sectioncheck *mismatch,
1412 const char *fromsec,
1413 unsigned long long fromaddr,
1414 const char *fromsym,
1416 const char *tosec, const char *tosym,
1419 const char *from, *from_p;
1420 const char *to, *to_p;
1424 sec_mismatch_count++;
1425 if (!sec_mismatch_verbose)
1428 get_pretty_name(from_is_func, &from, &from_p);
1429 get_pretty_name(to_is_func, &to, &to_p);
1431 warn("%s(%s+0x%llx): Section mismatch in reference from the %s %s%s "
1432 "to the %s %s:%s%s\n",
1433 modname, fromsec, fromaddr, from, fromsym, from_p, to, tosec,
1436 switch (mismatch->mismatch) {
1437 case TEXT_TO_ANY_INIT:
1438 prl_from = sec2annotation(fromsec);
1439 prl_to = sec2annotation(tosec);
1441 "The function %s%s() references\n"
1443 "This is often because %s lacks a %s\n"
1444 "annotation or the annotation of %s is wrong.\n",
1446 to, prl_to, tosym, to_p,
1447 fromsym, prl_to, tosym);
1451 case DATA_TO_ANY_INIT: {
1452 prl_to = sec2annotation(tosec);
1454 "The variable %s references\n"
1456 "If the reference is valid then annotate the\n"
1457 "variable with __init* or __refdata (see linux/init.h) "
1458 "or name the variable:\n",
1459 fromsym, to, prl_to, tosym, to_p);
1460 print_section_list(mismatch->symbol_white_list);
1464 case TEXT_TO_ANY_EXIT:
1465 prl_to = sec2annotation(tosec);
1467 "The function %s() references a %s in an exit section.\n"
1468 "Often the %s %s%s has valid usage outside the exit section\n"
1469 "and the fix is to remove the %sannotation of %s.\n",
1470 fromsym, to, to, tosym, to_p, prl_to, tosym);
1473 case DATA_TO_ANY_EXIT: {
1474 prl_to = sec2annotation(tosec);
1476 "The variable %s references\n"
1478 "If the reference is valid then annotate the\n"
1479 "variable with __exit* (see linux/init.h) or "
1480 "name the variable:\n",
1481 fromsym, to, prl_to, tosym, to_p);
1482 print_section_list(mismatch->symbol_white_list);
1486 case XXXINIT_TO_SOME_INIT:
1487 case XXXEXIT_TO_SOME_EXIT:
1488 prl_from = sec2annotation(fromsec);
1489 prl_to = sec2annotation(tosec);
1491 "The %s %s%s%s references\n"
1493 "If %s is only used by %s then\n"
1494 "annotate %s with a matching annotation.\n",
1495 from, prl_from, fromsym, from_p,
1496 to, prl_to, tosym, to_p,
1497 tosym, fromsym, tosym);
1501 case ANY_INIT_TO_ANY_EXIT:
1502 prl_from = sec2annotation(fromsec);
1503 prl_to = sec2annotation(tosec);
1505 "The %s %s%s%s references\n"
1507 "This is often seen when error handling "
1508 "in the init function\n"
1509 "uses functionality in the exit path.\n"
1510 "The fix is often to remove the %sannotation of\n"
1511 "%s%s so it may be used outside an exit section.\n",
1512 from, prl_from, fromsym, from_p,
1513 to, prl_to, tosym, to_p,
1514 prl_to, tosym, to_p);
1518 case ANY_EXIT_TO_ANY_INIT:
1519 prl_from = sec2annotation(fromsec);
1520 prl_to = sec2annotation(tosec);
1522 "The %s %s%s%s references\n"
1524 "This is often seen when error handling "
1525 "in the exit function\n"
1526 "uses functionality in the init path.\n"
1527 "The fix is often to remove the %sannotation of\n"
1528 "%s%s so it may be used outside an init section.\n",
1529 from, prl_from, fromsym, from_p,
1530 to, prl_to, tosym, to_p,
1531 prl_to, tosym, to_p);
1535 case EXPORT_TO_INIT_EXIT:
1536 prl_to = sec2annotation(tosec);
1538 "The symbol %s is exported and annotated %s\n"
1539 "Fix this by removing the %sannotation of %s "
1540 "or drop the export.\n",
1541 tosym, prl_to, prl_to, tosym);
1544 case EXTABLE_TO_NON_TEXT:
1545 fatal("There's a special handler for this mismatch type, "
1546 "we should never get here.");
1549 fprintf(stderr, "\n");
1552 static void default_mismatch_handler(const char *modname, struct elf_info *elf,
1553 const struct sectioncheck* const mismatch,
1554 Elf_Rela *r, Elf_Sym *sym, const char *fromsec)
1560 const char *fromsym;
1562 from = find_elf_symbol2(elf, r->r_offset, fromsec);
1563 fromsym = sym_name(elf, from);
1565 if (!strncmp(fromsym, "reference___initcall",
1566 sizeof("reference___initcall")-1))
1569 tosec = sec_name(elf, get_secindex(elf, sym));
1570 to = find_elf_symbol(elf, r->r_addend, sym);
1571 tosym = sym_name(elf, to);
1573 /* check whitelist - we may ignore it */
1574 if (secref_whitelist(mismatch,
1575 fromsec, fromsym, tosec, tosym)) {
1576 report_sec_mismatch(modname, mismatch,
1577 fromsec, r->r_offset, fromsym,
1578 is_function(from), tosec, tosym,
1583 static int is_executable_section(struct elf_info* elf, unsigned int section_index)
1585 if (section_index >= elf->num_sections)
1586 fatal("section_index is outside elf->num_sections!\n");
1588 return ((elf->sechdrs[section_index].sh_flags & SHF_EXECINSTR) == SHF_EXECINSTR);
1592 * We rely on a gross hack in section_rel[a]() calling find_extable_entry_size()
1593 * to know the sizeof(struct exception_table_entry) for the target architecture.
1595 static unsigned int extable_entry_size = 0;
1596 static void find_extable_entry_size(const char* const sec, const Elf_Rela* r)
1599 * If we're currently checking the second relocation within __ex_table,
1600 * that relocation offset tells us the offsetof(struct
1601 * exception_table_entry, fixup) which is equal to sizeof(struct
1602 * exception_table_entry) divided by two. We use that to our advantage
1603 * since there's no portable way to get that size as every architecture
1604 * seems to go with different sized types. Not pretty but better than
1605 * hard-coding the size for every architecture..
1607 if (!extable_entry_size)
1608 extable_entry_size = r->r_offset * 2;
1611 static inline bool is_extable_fault_address(Elf_Rela *r)
1614 * extable_entry_size is only discovered after we've handled the
1615 * _second_ relocation in __ex_table, so only abort when we're not
1616 * handling the first reloc and extable_entry_size is zero.
1618 if (r->r_offset && extable_entry_size == 0)
1619 fatal("extable_entry size hasn't been discovered!\n");
1621 return ((r->r_offset == 0) ||
1622 (r->r_offset % extable_entry_size == 0));
1625 #define is_second_extable_reloc(Start, Cur, Sec) \
1626 (((Cur) == (Start) + 1) && (strcmp("__ex_table", (Sec)) == 0))
1628 static void report_extable_warnings(const char* modname, struct elf_info* elf,
1629 const struct sectioncheck* const mismatch,
1630 Elf_Rela* r, Elf_Sym* sym,
1631 const char* fromsec, const char* tosec)
1633 Elf_Sym* fromsym = find_elf_symbol2(elf, r->r_offset, fromsec);
1634 const char* fromsym_name = sym_name(elf, fromsym);
1635 Elf_Sym* tosym = find_elf_symbol(elf, r->r_addend, sym);
1636 const char* tosym_name = sym_name(elf, tosym);
1637 const char* from_pretty_name;
1638 const char* from_pretty_name_p;
1639 const char* to_pretty_name;
1640 const char* to_pretty_name_p;
1642 get_pretty_name(is_function(fromsym),
1643 &from_pretty_name, &from_pretty_name_p);
1644 get_pretty_name(is_function(tosym),
1645 &to_pretty_name, &to_pretty_name_p);
1647 warn("%s(%s+0x%lx): Section mismatch in reference"
1648 " from the %s %s%s to the %s %s:%s%s\n",
1649 modname, fromsec, (long)r->r_offset, from_pretty_name,
1650 fromsym_name, from_pretty_name_p,
1651 to_pretty_name, tosec, tosym_name, to_pretty_name_p);
1653 if (!match(tosec, mismatch->bad_tosec) &&
1654 is_executable_section(elf, get_secindex(elf, sym)))
1656 "The relocation at %s+0x%lx references\n"
1657 "section \"%s\" which is not in the list of\n"
1658 "authorized sections. If you're adding a new section\n"
1659 "and/or if this reference is valid, add \"%s\" to the\n"
1660 "list of authorized sections to jump to on fault.\n"
1661 "This can be achieved by adding \"%s\" to \n"
1662 "OTHER_TEXT_SECTIONS in scripts/mod/modpost.c.\n",
1663 fromsec, (long)r->r_offset, tosec, tosec, tosec);
1666 static void extable_mismatch_handler(const char* modname, struct elf_info *elf,
1667 const struct sectioncheck* const mismatch,
1668 Elf_Rela* r, Elf_Sym* sym,
1669 const char *fromsec)
1671 const char* tosec = sec_name(elf, get_secindex(elf, sym));
1673 sec_mismatch_count++;
1675 if (sec_mismatch_verbose)
1676 report_extable_warnings(modname, elf, mismatch, r, sym,
1679 if (match(tosec, mismatch->bad_tosec))
1680 fatal("The relocation at %s+0x%lx references\n"
1681 "section \"%s\" which is black-listed.\n"
1682 "Something is seriously wrong and should be fixed.\n"
1683 "You might get more information about where this is\n"
1684 "coming from by using scripts/check_extable.sh %s\n",
1685 fromsec, (long)r->r_offset, tosec, modname);
1686 else if (!is_executable_section(elf, get_secindex(elf, sym))) {
1687 if (is_extable_fault_address(r))
1688 fatal("The relocation at %s+0x%lx references\n"
1689 "section \"%s\" which is not executable, IOW\n"
1690 "it is not possible for the kernel to fault\n"
1691 "at that address. Something is seriously wrong\n"
1692 "and should be fixed.\n",
1693 fromsec, (long)r->r_offset, tosec);
1695 fatal("The relocation at %s+0x%lx references\n"
1696 "section \"%s\" which is not executable, IOW\n"
1697 "the kernel will fault if it ever tries to\n"
1698 "jump to it. Something is seriously wrong\n"
1699 "and should be fixed.\n",
1700 fromsec, (long)r->r_offset, tosec);
1704 static void check_section_mismatch(const char *modname, struct elf_info *elf,
1705 Elf_Rela *r, Elf_Sym *sym, const char *fromsec)
1707 const char *tosec = sec_name(elf, get_secindex(elf, sym));;
1708 const struct sectioncheck *mismatch = section_mismatch(fromsec, tosec);
1711 if (mismatch->handler)
1712 mismatch->handler(modname, elf, mismatch,
1715 default_mismatch_handler(modname, elf, mismatch,
1720 static unsigned int *reloc_location(struct elf_info *elf,
1721 Elf_Shdr *sechdr, Elf_Rela *r)
1723 Elf_Shdr *sechdrs = elf->sechdrs;
1724 int section = sechdr->sh_info;
1726 return (void *)elf->hdr + sechdrs[section].sh_offset +
1730 static int addend_386_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r)
1732 unsigned int r_typ = ELF_R_TYPE(r->r_info);
1733 unsigned int *location = reloc_location(elf, sechdr, r);
1737 r->r_addend = TO_NATIVE(*location);
1740 r->r_addend = TO_NATIVE(*location) + 4;
1741 /* For CONFIG_RELOCATABLE=y */
1742 if (elf->hdr->e_type == ET_EXEC)
1743 r->r_addend += r->r_offset;
1750 #define R_ARM_CALL 28
1752 #ifndef R_ARM_JUMP24
1753 #define R_ARM_JUMP24 29
1756 #ifndef R_ARM_THM_CALL
1757 #define R_ARM_THM_CALL 10
1759 #ifndef R_ARM_THM_JUMP24
1760 #define R_ARM_THM_JUMP24 30
1762 #ifndef R_ARM_THM_JUMP19
1763 #define R_ARM_THM_JUMP19 51
1766 static int32_t sign_extend32(int32_t value, int index)
1768 uint8_t shift = 31 - index;
1770 return (int32_t)(value << shift) >> shift;
1773 static int addend_arm_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r)
1775 unsigned int r_typ = ELF_R_TYPE(r->r_info);
1776 Elf_Sym *sym = elf->symtab_start + ELF_R_SYM(r->r_info);
1777 void *loc = reloc_location(elf, sechdr, r);
1783 inst = TO_NATIVE(*(uint32_t *)loc);
1784 r->r_addend = inst + sym->st_value;
1789 inst = TO_NATIVE(*(uint32_t *)loc);
1790 offset = sign_extend32((inst & 0x00ffffff) << 2, 25);
1791 r->r_addend = offset + sym->st_value + 8;
1793 case R_ARM_THM_CALL:
1794 case R_ARM_THM_JUMP24:
1795 case R_ARM_THM_JUMP19:
1796 /* From ARM ABI: ((S + A) | T) - P */
1797 r->r_addend = (int)(long)(elf->hdr +
1799 (r->r_offset - sechdr->sh_addr));
1807 static int addend_mips_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r)
1809 unsigned int r_typ = ELF_R_TYPE(r->r_info);
1810 unsigned int *location = reloc_location(elf, sechdr, r);
1813 if (r_typ == R_MIPS_HI16)
1814 return 1; /* skip this */
1815 inst = TO_NATIVE(*location);
1818 r->r_addend = inst & 0xffff;
1821 r->r_addend = (inst & 0x03ffffff) << 2;
1830 static void section_rela(const char *modname, struct elf_info *elf,
1837 const char *fromsec;
1839 Elf_Rela *start = (void *)elf->hdr + sechdr->sh_offset;
1840 Elf_Rela *stop = (void *)start + sechdr->sh_size;
1842 fromsec = sech_name(elf, sechdr);
1843 fromsec += strlen(".rela");
1844 /* if from section (name) is know good then skip it */
1845 if (match(fromsec, section_white_list))
1848 for (rela = start; rela < stop; rela++) {
1849 r.r_offset = TO_NATIVE(rela->r_offset);
1850 #if KERNEL_ELFCLASS == ELFCLASS64
1851 if (elf->hdr->e_machine == EM_MIPS) {
1853 r_sym = ELF64_MIPS_R_SYM(rela->r_info);
1854 r_sym = TO_NATIVE(r_sym);
1855 r_typ = ELF64_MIPS_R_TYPE(rela->r_info);
1856 r.r_info = ELF64_R_INFO(r_sym, r_typ);
1858 r.r_info = TO_NATIVE(rela->r_info);
1859 r_sym = ELF_R_SYM(r.r_info);
1862 r.r_info = TO_NATIVE(rela->r_info);
1863 r_sym = ELF_R_SYM(r.r_info);
1865 r.r_addend = TO_NATIVE(rela->r_addend);
1866 sym = elf->symtab_start + r_sym;
1867 /* Skip special sections */
1868 if (is_shndx_special(sym->st_shndx))
1870 if (is_second_extable_reloc(start, rela, fromsec))
1871 find_extable_entry_size(fromsec, &r);
1872 check_section_mismatch(modname, elf, &r, sym, fromsec);
1876 static void section_rel(const char *modname, struct elf_info *elf,
1883 const char *fromsec;
1885 Elf_Rel *start = (void *)elf->hdr + sechdr->sh_offset;
1886 Elf_Rel *stop = (void *)start + sechdr->sh_size;
1888 fromsec = sech_name(elf, sechdr);
1889 fromsec += strlen(".rel");
1890 /* if from section (name) is know good then skip it */
1891 if (match(fromsec, section_white_list))
1894 for (rel = start; rel < stop; rel++) {
1895 r.r_offset = TO_NATIVE(rel->r_offset);
1896 #if KERNEL_ELFCLASS == ELFCLASS64
1897 if (elf->hdr->e_machine == EM_MIPS) {
1899 r_sym = ELF64_MIPS_R_SYM(rel->r_info);
1900 r_sym = TO_NATIVE(r_sym);
1901 r_typ = ELF64_MIPS_R_TYPE(rel->r_info);
1902 r.r_info = ELF64_R_INFO(r_sym, r_typ);
1904 r.r_info = TO_NATIVE(rel->r_info);
1905 r_sym = ELF_R_SYM(r.r_info);
1908 r.r_info = TO_NATIVE(rel->r_info);
1909 r_sym = ELF_R_SYM(r.r_info);
1912 switch (elf->hdr->e_machine) {
1914 if (addend_386_rel(elf, sechdr, &r))
1918 if (addend_arm_rel(elf, sechdr, &r))
1922 if (addend_mips_rel(elf, sechdr, &r))
1926 sym = elf->symtab_start + r_sym;
1927 /* Skip special sections */
1928 if (is_shndx_special(sym->st_shndx))
1930 if (is_second_extable_reloc(start, rel, fromsec))
1931 find_extable_entry_size(fromsec, &r);
1932 check_section_mismatch(modname, elf, &r, sym, fromsec);
1937 * A module includes a number of sections that are discarded
1938 * either when loaded or when used as built-in.
1939 * For loaded modules all functions marked __init and all data
1940 * marked __initdata will be discarded when the module has been initialized.
1941 * Likewise for modules used built-in the sections marked __exit
1942 * are discarded because __exit marked function are supposed to be called
1943 * only when a module is unloaded which never happens for built-in modules.
1944 * The check_sec_ref() function traverses all relocation records
1945 * to find all references to a section that reference a section that will
1946 * be discarded and warns about it.
1948 static void check_sec_ref(struct module *mod, const char *modname,
1949 struct elf_info *elf)
1952 Elf_Shdr *sechdrs = elf->sechdrs;
1954 /* Walk through all sections */
1955 for (i = 0; i < elf->num_sections; i++) {
1956 check_section(modname, elf, &elf->sechdrs[i]);
1957 /* We want to process only relocation sections and not .init */
1958 if (sechdrs[i].sh_type == SHT_RELA)
1959 section_rela(modname, elf, &elf->sechdrs[i]);
1960 else if (sechdrs[i].sh_type == SHT_REL)
1961 section_rel(modname, elf, &elf->sechdrs[i]);
1965 static char *remove_dot(char *s)
1967 size_t n = strcspn(s, ".");
1970 size_t m = strspn(s + n + 1, "0123456789");
1971 if (m && (s[n + m + 1] == '.' || s[n + m + 1] == 0))
1977 static void read_symbols(char *modname)
1979 const char *symname;
1983 struct elf_info info = { };
1986 if (!parse_elf(&info, modname))
1989 mod = new_module(modname);
1991 /* When there's no vmlinux, don't print warnings about
1992 * unresolved symbols (since there'll be too many ;) */
1993 if (is_vmlinux(modname)) {
1998 license = get_modinfo(info.modinfo, info.modinfo_len, "license");
1999 if (info.modinfo && !license && !is_vmlinux(modname))
2000 warn("modpost: missing MODULE_LICENSE() in %s\n"
2001 "see include/linux/module.h for "
2002 "more information\n", modname);
2004 if (license_is_gpl_compatible(license))
2005 mod->gpl_compatible = 1;
2007 mod->gpl_compatible = 0;
2010 license = get_next_modinfo(info.modinfo, info.modinfo_len,
2011 "license", license);
2014 for (sym = info.symtab_start; sym < info.symtab_stop; sym++) {
2015 symname = remove_dot(info.strtab + sym->st_name);
2017 handle_modversions(mod, &info, sym, symname);
2018 handle_moddevtable(mod, &info, sym, symname);
2020 if (!is_vmlinux(modname) ||
2021 (is_vmlinux(modname) && vmlinux_section_warnings))
2022 check_sec_ref(mod, modname, &info);
2024 version = get_modinfo(info.modinfo, info.modinfo_len, "version");
2026 maybe_frob_rcs_version(modname, version, info.modinfo,
2027 version - (char *)info.hdr);
2028 if (version || (all_versions && !is_vmlinux(modname)))
2029 get_src_version(modname, mod->srcversion,
2030 sizeof(mod->srcversion)-1);
2032 parse_elf_finish(&info);
2034 /* Our trick to get versioning for module struct etc. - it's
2035 * never passed as an argument to an exported function, so
2036 * the automatic versioning doesn't pick it up, but it's really
2037 * important anyhow */
2039 mod->unres = alloc_symbol("module_layout", 0, mod->unres);
2042 static void read_symbols_from_files(const char *filename)
2045 char fname[PATH_MAX];
2047 if (strcmp(filename, "-") != 0) {
2048 in = fopen(filename, "r");
2050 fatal("Can't open filenames file %s: %m", filename);
2053 while (fgets(fname, PATH_MAX, in) != NULL) {
2054 if (strends(fname, "\n"))
2055 fname[strlen(fname)-1] = '\0';
2056 read_symbols(fname);
2065 /* We first write the generated file into memory using the
2066 * following helper, then compare to the file on disk and
2067 * only update the later if anything changed */
2069 void __attribute__((format(printf, 2, 3))) buf_printf(struct buffer *buf,
2070 const char *fmt, ...)
2077 len = vsnprintf(tmp, SZ, fmt, ap);
2078 buf_write(buf, tmp, len);
2082 void buf_write(struct buffer *buf, const char *s, int len)
2084 if (buf->size - buf->pos < len) {
2085 buf->size += len + SZ;
2086 buf->p = NOFAIL(realloc(buf->p, buf->size));
2088 strncpy(buf->p + buf->pos, s, len);
2092 static void check_for_gpl_usage(enum export exp, const char *m, const char *s)
2094 const char *e = is_vmlinux(m) ?"":".ko";
2098 fatal("modpost: GPL-incompatible module %s%s "
2099 "uses GPL-only symbol '%s'\n", m, e, s);
2101 case export_unused_gpl:
2102 fatal("modpost: GPL-incompatible module %s%s "
2103 "uses GPL-only symbol marked UNUSED '%s'\n", m, e, s);
2105 case export_gpl_future:
2106 warn("modpost: GPL-incompatible module %s%s "
2107 "uses future GPL-only symbol '%s'\n", m, e, s);
2111 case export_unknown:
2117 static void check_for_unused(enum export exp, const char *m, const char *s)
2119 const char *e = is_vmlinux(m) ?"":".ko";
2123 case export_unused_gpl:
2124 warn("modpost: module %s%s "
2125 "uses symbol '%s' marked UNUSED\n", m, e, s);
2133 static void check_exports(struct module *mod)
2135 struct symbol *s, *exp;
2137 for (s = mod->unres; s; s = s->next) {
2138 const char *basename;
2139 exp = find_symbol(s->name);
2140 if (!exp || exp->module == mod)
2142 basename = strrchr(mod->name, '/');
2146 basename = mod->name;
2147 if (!mod->gpl_compatible)
2148 check_for_gpl_usage(exp->export, basename, exp->name);
2149 check_for_unused(exp->export, basename, exp->name);
2153 static int check_modname_len(struct module *mod)
2155 const char *mod_name;
2157 mod_name = strrchr(mod->name, '/');
2158 if (mod_name == NULL)
2159 mod_name = mod->name;
2162 if (strlen(mod_name) >= MODULE_NAME_LEN) {
2163 merror("module name is too long [%s.ko]\n", mod->name);
2171 * Header for the generated file
2173 static void add_header(struct buffer *b, struct module *mod)
2175 buf_printf(b, "#include <linux/module.h>\n");
2176 buf_printf(b, "#include <linux/vermagic.h>\n");
2177 buf_printf(b, "#include <linux/compiler.h>\n");
2178 buf_printf(b, "\n");
2179 buf_printf(b, "MODULE_INFO(vermagic, VERMAGIC_STRING);\n");
2180 buf_printf(b, "MODULE_INFO(name, KBUILD_MODNAME);\n");
2181 buf_printf(b, "\n");
2182 buf_printf(b, "__visible struct module __this_module\n");
2183 buf_printf(b, "__attribute__((section(\".gnu.linkonce.this_module\"))) = {\n");
2184 buf_printf(b, "\t.name = KBUILD_MODNAME,\n");
2186 buf_printf(b, "\t.init = init_module,\n");
2187 if (mod->has_cleanup)
2188 buf_printf(b, "#ifdef CONFIG_MODULE_UNLOAD\n"
2189 "\t.exit = cleanup_module,\n"
2191 buf_printf(b, "\t.arch = MODULE_ARCH_INIT,\n");
2192 buf_printf(b, "};\n");
2195 static void add_intree_flag(struct buffer *b, int is_intree)
2198 buf_printf(b, "\nMODULE_INFO(intree, \"Y\");\n");
2201 /* Cannot check for assembler */
2202 static void add_retpoline(struct buffer *b)
2204 buf_printf(b, "\n#ifdef CONFIG_RETPOLINE\n");
2205 buf_printf(b, "MODULE_INFO(retpoline, \"Y\");\n");
2206 buf_printf(b, "#endif\n");
2209 static void add_staging_flag(struct buffer *b, const char *name)
2211 static const char *staging_dir = "drivers/staging";
2213 if (strncmp(staging_dir, name, strlen(staging_dir)) == 0)
2214 buf_printf(b, "\nMODULE_INFO(staging, \"Y\");\n");
2218 * Record CRCs for unresolved symbols
2220 static int add_versions(struct buffer *b, struct module *mod)
2222 struct symbol *s, *exp;
2225 for (s = mod->unres; s; s = s->next) {
2226 exp = find_symbol(s->name);
2227 if (!exp || exp->module == mod) {
2228 if (have_vmlinux && !s->weak) {
2229 if (warn_unresolved) {
2230 warn("\"%s\" [%s.ko] undefined!\n",
2231 s->name, mod->name);
2233 merror("\"%s\" [%s.ko] undefined!\n",
2234 s->name, mod->name);
2240 s->module = exp->module;
2241 s->crc_valid = exp->crc_valid;
2248 buf_printf(b, "\n");
2249 buf_printf(b, "static const struct modversion_info ____versions[]\n");
2250 buf_printf(b, "__used\n");
2251 buf_printf(b, "__attribute__((section(\"__versions\"))) = {\n");
2253 for (s = mod->unres; s; s = s->next) {
2256 if (!s->crc_valid) {
2257 warn("\"%s\" [%s.ko] has no CRC!\n",
2258 s->name, mod->name);
2261 if (strlen(s->name) >= MODULE_NAME_LEN) {
2262 merror("too long symbol \"%s\" [%s.ko]\n",
2263 s->name, mod->name);
2267 buf_printf(b, "\t{ %#8x, __VMLINUX_SYMBOL_STR(%s) },\n",
2271 buf_printf(b, "};\n");
2276 static void add_depends(struct buffer *b, struct module *mod,
2277 struct module *modules)
2283 for (m = modules; m; m = m->next)
2284 m->seen = is_vmlinux(m->name);
2286 buf_printf(b, "\n");
2287 buf_printf(b, "static const char __module_depends[]\n");
2288 buf_printf(b, "__used\n");
2289 buf_printf(b, "__attribute__((section(\".modinfo\"))) =\n");
2290 buf_printf(b, "\"depends=");
2291 for (s = mod->unres; s; s = s->next) {
2296 if (s->module->seen)
2299 s->module->seen = 1;
2300 p = strrchr(s->module->name, '/');
2304 p = s->module->name;
2305 buf_printf(b, "%s%s", first ? "" : ",", p);
2308 buf_printf(b, "\";\n");
2311 static void add_srcversion(struct buffer *b, struct module *mod)
2313 if (mod->srcversion[0]) {
2314 buf_printf(b, "\n");
2315 buf_printf(b, "MODULE_INFO(srcversion, \"%s\");\n",
2320 static void write_if_changed(struct buffer *b, const char *fname)
2326 file = fopen(fname, "r");
2330 if (fstat(fileno(file), &st) < 0)
2333 if (st.st_size != b->pos)
2336 tmp = NOFAIL(malloc(b->pos));
2337 if (fread(tmp, 1, b->pos, file) != b->pos)
2340 if (memcmp(tmp, b->p, b->pos) != 0)
2352 file = fopen(fname, "w");
2357 if (fwrite(b->p, 1, b->pos, file) != b->pos) {
2364 /* parse Module.symvers file. line format:
2365 * 0x12345678<tab>symbol<tab>module[[<tab>export]<tab>something]
2367 static void read_dump(const char *fname, unsigned int kernel)
2369 unsigned long size, pos = 0;
2370 void *file = grab_file(fname, &size);
2374 /* No symbol versions, silently ignore */
2377 while ((line = get_next_line(&pos, file, size))) {
2378 char *symname, *modname, *d, *export, *end;
2383 if (!(symname = strchr(line, '\t')))
2386 if (!(modname = strchr(symname, '\t')))
2389 if ((export = strchr(modname, '\t')) != NULL)
2391 if (export && ((end = strchr(export, '\t')) != NULL))
2393 crc = strtoul(line, &d, 16);
2394 if (*symname == '\0' || *modname == '\0' || *d != '\0')
2396 mod = find_module(modname);
2398 if (is_vmlinux(modname))
2400 mod = new_module(modname);
2403 s = sym_add_exported(symname, mod, export_no(export));
2406 sym_update_crc(symname, mod, crc, export_no(export));
2408 release_file(file, size);
2411 release_file(file, size);
2412 fatal("parse error in symbol dump file\n");
2415 /* For normal builds always dump all symbols.
2416 * For external modules only dump symbols
2417 * that are not read from kernel Module.symvers.
2419 static int dump_sym(struct symbol *sym)
2421 if (!external_module)
2423 if (sym->vmlinux || sym->kernel)
2428 static void write_dump(const char *fname)
2430 struct buffer buf = { };
2431 struct symbol *symbol;
2434 for (n = 0; n < SYMBOL_HASH_SIZE ; n++) {
2435 symbol = symbolhash[n];
2437 if (dump_sym(symbol))
2438 buf_printf(&buf, "0x%08x\t%s\t%s\t%s\n",
2439 symbol->crc, symbol->name,
2440 symbol->module->name,
2441 export_str(symbol->export));
2442 symbol = symbol->next;
2445 write_if_changed(&buf, fname);
2449 struct ext_sym_list {
2450 struct ext_sym_list *next;
2454 int main(int argc, char **argv)
2457 struct buffer buf = { };
2458 char *kernel_read = NULL, *module_read = NULL;
2459 char *dump_write = NULL, *files_source = NULL;
2462 struct ext_sym_list *extsym_iter;
2463 struct ext_sym_list *extsym_start = NULL;
2465 while ((opt = getopt(argc, argv, "i:I:e:mnsST:o:awM:K:E")) != -1) {
2468 kernel_read = optarg;
2471 module_read = optarg;
2472 external_module = 1;
2475 external_module = 1;
2477 NOFAIL(malloc(sizeof(*extsym_iter)));
2478 extsym_iter->next = extsym_start;
2479 extsym_iter->file = optarg;
2480 extsym_start = extsym_iter;
2486 ignore_missing_files = 1;
2489 dump_write = optarg;
2495 vmlinux_section_warnings = 0;
2498 sec_mismatch_verbose = 0;
2501 files_source = optarg;
2504 warn_unresolved = 1;
2507 sec_mismatch_fatal = 1;
2515 read_dump(kernel_read, 1);
2517 read_dump(module_read, 0);
2518 while (extsym_start) {
2519 read_dump(extsym_start->file, 0);
2520 extsym_iter = extsym_start->next;
2522 extsym_start = extsym_iter;
2525 while (optind < argc)
2526 read_symbols(argv[optind++]);
2529 read_symbols_from_files(files_source);
2531 for (mod = modules; mod; mod = mod->next) {
2539 for (mod = modules; mod; mod = mod->next) {
2540 char fname[PATH_MAX];
2547 err |= check_modname_len(mod);
2548 add_header(&buf, mod);
2549 add_intree_flag(&buf, !external_module);
2550 add_retpoline(&buf);
2551 add_staging_flag(&buf, mod->name);
2552 err |= add_versions(&buf, mod);
2553 add_depends(&buf, mod, modules);
2554 add_moddevtable(&buf, mod);
2555 add_srcversion(&buf, mod);
2557 sprintf(fname, "%s.mod.c", mod->name);
2558 write_if_changed(&buf, fname);
2561 write_dump(dump_write);
2562 if (sec_mismatch_count) {
2563 if (!sec_mismatch_verbose) {
2564 warn("modpost: Found %d section mismatch(es).\n"
2565 "To see full details build your kernel with:\n"
2566 "'make CONFIG_DEBUG_SECTION_MISMATCH=y'\n",
2567 sec_mismatch_count);
2569 if (sec_mismatch_fatal) {
2570 fatal("modpost: Section mismatches detected.\n"
2571 "Set CONFIG_SECTION_MISMATCH_WARN_ONLY=y to allow them.\n");