mm: fix section mismatch warnings
[sfrench/cifs-2.6.git] / scripts / mod / modpost.c
index 113dc77b9f60f9e147239bc3daff8bc92164c80c..8424d1f53bbe6e2b9cb646ee32d94fe239c89938 100644 (file)
@@ -384,6 +384,7 @@ static int parse_elf(struct elf_info *info, const char *filename)
                sechdrs[i].sh_size   = TO_NATIVE(sechdrs[i].sh_size);
                sechdrs[i].sh_link   = TO_NATIVE(sechdrs[i].sh_link);
                sechdrs[i].sh_name   = TO_NATIVE(sechdrs[i].sh_name);
+               sechdrs[i].sh_info   = TO_NATIVE(sechdrs[i].sh_info);
        }
        /* Find symbol table. */
        for (i = 1; i < hdr->e_shnum; i++) {
@@ -582,6 +583,12 @@ static int strrcmp(const char *s, const char *sub)
 
 /**
  * Whitelist to allow certain references to pass with no warning.
+ *
+ * Pattern 0:
+ *   Do not warn if funtion/data are marked with __init_refok/__initdata_refok.
+ *   The pattern is identified by:
+ *   fromsec = .text.init.refok | .data.init.refok
+ *
  * Pattern 1:
  *   If a module parameter is declared __initdata and permissions=0
  *   then this is legal despite the warning generated.
@@ -619,14 +626,6 @@ static int strrcmp(const char *s, const char *sub)
  *   This pattern is identified by
  *   refsymname = __init_begin, _sinittext, _einittext
  *
- * Pattern 6:
- *   During the early init phase we have references from .init.text to
- *   .text we have an intended section mismatch - do not warn about it.
- *   See kernel_init() in init/main.c
- *   tosec   = .init.text
- *   fromsec = .text
- *   atsym = kernel_init
- *
  * Pattern 7:
  *  Logos used in drivers/video/logo reside in __initdata but the
  *  funtion that references them are EXPORT_SYMBOL() so cannot be
@@ -642,16 +641,11 @@ static int strrcmp(const char *s, const char *sub)
  *  tosec   = .init.text
  *  fromsec  = .paravirtprobe
  *
- * Pattern 9:
- *  Some of functions are common code between boot time and hotplug
- *  time. The bootmem allocater is called only boot time in its
- *  functions. So it's ok to reference.
- *  tosec    = .init.text
- *
  * Pattern 10:
- *  ia64 has machvec table for each platform. It is mixture of function
- *  pointer of .init.text and .text.
- *  fromsec  = .machvec
+ *  ia64 has machvec table for each platform and
+ *  powerpc has a machine desc table for each platform.
+ *  It is mixture of function pointers of .init.text and .text.
+ *  fromsec  = .machvec | .machine.desc
  **/
 static int secref_whitelist(const char *modname, const char *tosec,
                            const char *fromsec, const char *atsym,
@@ -678,11 +672,10 @@ static int secref_whitelist(const char *modname, const char *tosec,
                NULL
        };
 
-       const char *pat4sym[] = {
-               "sparse_index_alloc",
-               "zone_wait_table_init",
-               NULL
-       };
+       /* Check for pattern 0 */
+       if ((strcmp(fromsec, ".text.init.refok") == 0) ||
+           (strcmp(fromsec, ".data.init.refok") == 0))
+               return 1;
 
        /* Check for pattern 1 */
        if (strcmp(tosec, ".init.data") != 0)
@@ -725,12 +718,6 @@ static int secref_whitelist(const char *modname, const char *tosec,
                if (strcmp(refsymname, *s) == 0)
                        return 1;
 
-       /* Check for pattern 6 */
-       if ((strcmp(tosec, ".init.text") == 0) &&
-           (strcmp(fromsec, ".text") == 0) &&
-           (strcmp(refsymname, "kernel_init") == 0))
-               return 1;
-
        /* Check for pattern 7 */
        if ((strcmp(tosec, ".init.data") == 0) &&
            (strncmp(fromsec, ".text", strlen(".text")) == 0) &&
@@ -742,15 +729,9 @@ static int secref_whitelist(const char *modname, const char *tosec,
            (strcmp(fromsec, ".paravirtprobe") == 0))
                return 1;
 
-       /* Check for pattern 9 */
-       if ((strcmp(tosec, ".init.text") == 0) &&
-           (strcmp(fromsec, ".text") == 0))
-               for (s = pat4sym; *s; s++)
-                       if (strcmp(atsym, *s) == 0)
-                               return 1;
-
        /* Check for pattern 10 */
-       if (strcmp(fromsec, ".machvec") == 0)
+       if ((strcmp(fromsec, ".machvec") == 0) ||
+           (strcmp(fromsec, ".machine.desc") == 0))
                return 1;
 
        return 0;
@@ -773,6 +754,8 @@ static Elf_Sym *find_elf_symbol(struct elf_info *elf, Elf_Addr addr,
        for (sym = elf->symtab_start; sym < elf->symtab_stop; sym++) {
                if (sym->st_shndx != relsym->st_shndx)
                        continue;
+               if (ELF_ST_TYPE(sym->st_info) == STT_SECTION)
+                       continue;
                if (sym->st_value == addr)
                        return sym;
        }
@@ -884,33 +867,99 @@ static void warn_sec_mismatch(const char *modname, const char *fromsec,
                             elf->strtab + before->st_name, refsymname))
                return;
 
+       /* fromsec whitelist - without a valid 'before'
+        * powerpc has a GOT table in .got2 section */
+       if (strcmp(fromsec, ".got2") == 0)
+               return;
+
        if (before && after) {
-               warn("%s - Section mismatch: reference to %s:%s from %s "
-                    "between '%s' (at offset 0x%llx) and '%s'\n",
-                    modname, secname, refsymname, fromsec,
+               warn("%s(%s+0x%llx): Section mismatch: reference to %s:%s "
+                    "(between '%s' and '%s')\n",
+                    modname, fromsec, (unsigned long long)r.r_offset,
+                    secname, refsymname,
                     elf->strtab + before->st_name,
-                    (long long)r.r_offset,
                     elf->strtab + after->st_name);
        } else if (before) {
-               warn("%s - Section mismatch: reference to %s:%s from %s "
-                    "after '%s' (at offset 0x%llx)\n",
-                    modname, secname, refsymname, fromsec,
-                    elf->strtab + before->st_name,
-                    (long long)r.r_offset);
+               warn("%s(%s+0x%llx): Section mismatch: reference to %s:%s "
+                    "(after '%s')\n",
+                    modname, fromsec, (unsigned long long)r.r_offset,
+                    secname, refsymname,
+                    elf->strtab + before->st_name);
        } else if (after) {
-               warn("%s - Section mismatch: reference to %s:%s from %s "
+               warn("%s(%s+0x%llx): Section mismatch: reference to %s:%s "
                     "before '%s' (at offset -0x%llx)\n",
-                    modname, secname, refsymname, fromsec,
-                    elf->strtab + after->st_name,
-                    (long long)r.r_offset);
+                    modname, fromsec, (unsigned long long)r.r_offset,
+                    secname, refsymname,
+                    elf->strtab + after->st_name);
        } else {
-               warn("%s - Section mismatch: reference to %s:%s from %s "
-                    "(offset 0x%llx)\n",
-                    modname, secname, fromsec, refsymname,
-                    (long long)r.r_offset);
+               warn("%s(%s+0x%llx): Section mismatch: reference to %s:%s\n",
+                    modname, fromsec, (unsigned long long)r.r_offset,
+                    secname, refsymname);
        }
 }
 
+static void addend_386_rel(struct elf_info *elf, int section, Elf_Rela *r)
+{
+       Elf_Shdr *sechdrs = elf->sechdrs;
+       unsigned int r_typ;
+       unsigned int *location;
+
+       r_typ = ELF_R_TYPE(r->r_info);
+       location = (void *)elf->hdr +
+               sechdrs[sechdrs[section].sh_info].sh_offset + r->r_offset;
+       switch (r_typ) {
+       case R_386_32:
+               r->r_addend = TO_NATIVE(*location);
+               break;
+       case R_386_PC32:
+               r->r_addend = TO_NATIVE(*location) + 4;
+               break;
+       }
+}
+
+static void addend_arm_rel(struct elf_info *elf, int section, Elf_Rela *r)
+{
+       Elf_Shdr *sechdrs = elf->sechdrs;
+       unsigned int r_typ;
+       unsigned int *location;
+
+       r_typ = ELF_R_TYPE(r->r_info);
+       location = (void *)elf->hdr +
+               sechdrs[sechdrs[section].sh_info].sh_offset + r->r_offset;
+       switch (r_typ) {
+       case R_ARM_ABS32:
+               r->r_addend = TO_NATIVE(*location);
+               break;
+       case R_ARM_PC24:
+               r->r_addend = ((TO_NATIVE(*location) & 0x00ffffff) << 2) + 8;
+               break;
+       }
+}
+
+static int addend_mips_rel(struct elf_info *elf, int section, Elf_Rela *r)
+{
+       Elf_Shdr *sechdrs = elf->sechdrs;
+       unsigned int r_typ;
+       unsigned int *location;
+       unsigned int inst;
+
+       r_typ = ELF_R_TYPE(r->r_info);
+       if (r_typ == R_MIPS_HI16)
+               return 1;       /* skip this */
+       location = (void *)elf->hdr +
+               sechdrs[sechdrs[section].sh_info].sh_offset + r->r_offset;
+       inst = TO_NATIVE(*location);
+       switch (r_typ) {
+       case R_MIPS_LO16:
+               r->r_addend = ((inst & 0xffff) ^ 0x8000) - 0x8000;
+               break;
+       case R_MIPS_26:
+               r->r_addend = (inst & 0x03ffffff) << 2;
+               break;
+       }
+       return 0;
+}
+
 /**
  * A module includes a number of sections that are discarded
  * either when loaded or when used as built-in.
@@ -954,8 +1003,11 @@ static void check_sec_ref(struct module *mod, const char *modname,
                                r.r_offset = TO_NATIVE(rela->r_offset);
 #if KERNEL_ELFCLASS == ELFCLASS64
                                if (hdr->e_machine == EM_MIPS) {
+                                       unsigned int r_typ;
                                        r_sym = ELF64_MIPS_R_SYM(rela->r_info);
                                        r_sym = TO_NATIVE(r_sym);
+                                       r_typ = ELF64_MIPS_R_TYPE(rela->r_info);
+                                       r.r_info = ELF64_R_INFO(r_sym, r_typ);
                                } else {
                                        r.r_info = TO_NATIVE(rela->r_info);
                                        r_sym = ELF_R_SYM(r.r_info);
@@ -988,8 +1040,11 @@ static void check_sec_ref(struct module *mod, const char *modname,
                                r.r_offset = TO_NATIVE(rel->r_offset);
 #if KERNEL_ELFCLASS == ELFCLASS64
                                if (hdr->e_machine == EM_MIPS) {
+                                       unsigned int r_typ;
                                        r_sym = ELF64_MIPS_R_SYM(rel->r_info);
                                        r_sym = TO_NATIVE(r_sym);
+                                       r_typ = ELF64_MIPS_R_TYPE(rel->r_info);
+                                       r.r_info = ELF64_R_INFO(r_sym, r_typ);
                                } else {
                                        r.r_info = TO_NATIVE(rel->r_info);
                                        r_sym = ELF_R_SYM(r.r_info);
@@ -999,6 +1054,14 @@ static void check_sec_ref(struct module *mod, const char *modname,
                                r_sym = ELF_R_SYM(r.r_info);
 #endif
                                r.r_addend = 0;
+                               if (hdr->e_machine == EM_386)
+                                       addend_386_rel(elf, i, &r);
+                               else if (hdr->e_machine == EM_ARM)
+                                       addend_arm_rel(elf, i, &r);
+                               else if (hdr->e_machine == EM_MIPS) {
+                                       if (addend_mips_rel(elf, i, &r))
+                                               continue;
+                               }
                                sym = elf->symtab_start + r_sym;
                                /* Skip special sections */
                                if (sym->st_shndx >= SHN_LORESERVE)