Commit 93684d3b authored by Sam Ravnborg's avatar Sam Ravnborg
Browse files

kbuild: include symbol names in section mismatch warnings 



Try to look up the symbol that is referenced. Include the symbol
name in the warning message.

Signed-off-by: default avatarSam Ravnborg <sam@ravnborg.org>
parent 8ea80ca4

scripts/mod/modpost.c

+47 −17
Original line number Diff line number Diff line
@@ -451,6 +451,29 @@ static char *get_modinfo(void *modinfo, unsigned long modinfo_len, 
	return NULL;

}



/**

 * Find symbol based on relocation record info.

 * In some cases the symbol supplied is a valid symbol so

 * return refsym. If st_name != 0 we assume this is a valid symbol.

 * In other cases the symbol needs to be looked up in the symbol table

 * based on section and address.

 *  **/

static Elf_Sym *find_elf_symbol(struct elf_info *elf, Elf_Addr addr,

				Elf_Sym *relsym)

{

	Elf_Sym *sym;



	if (relsym->st_name != 0)

		return relsym;

	for (sym = elf->symtab_start; sym < elf->symtab_stop; sym++) {

		if (sym->st_shndx != relsym->st_shndx)

			continue;

		if (sym->st_value == addr)

			return sym;

	}

	return NULL;

}



/*

 * Find symbols before or equal addr and after addr - in the section sec

 **/
@@ -499,8 +522,9 @@ static void find_symbols_between(struct elf_info *elf, Elf_Addr addr, 
static void warn_sec_mismatch(const char *modname, const char *fromsec,

			      struct elf_info *elf, Elf_Sym *sym, Elf_Rela r)

{

	Elf_Sym *before;

	Elf_Sym *after;

	const char *refsymname = "";

	Elf_Sym *before, *after;

	Elf_Sym *refsym;

	Elf_Ehdr *hdr = elf->hdr;

	Elf_Shdr *sechdrs = elf->sechdrs;

	const char *secstrings = (void *)hdr +
@@ -509,29 +533,34 @@ static void warn_sec_mismatch(const char *modname, const char *fromsec, 
	

	find_symbols_between(elf, r.r_offset, fromsec, &before, &after);



	refsym = find_elf_symbol(elf, r.r_addend, sym);

	if (refsym && strlen(elf->strtab + refsym->st_name))

		refsymname = elf->strtab + refsym->st_name;

	

	if (before && after) {

		warn("%s - Section mismatch: reference to %s from %s "

		     "between '%s' (at offset 0x%lx) and '%s'\n",

		     modname, secname, fromsec,

		warn("%s - Section mismatch: reference to %s:%s from %s "

		     "between '%s' (at offset 0x%llx) and '%s'\n",

		     modname, secname, refsymname, fromsec,

		     elf->strtab + before->st_name,

		     (long)(r.r_offset - before->st_value),

		     (long long)r.r_offset,

		     elf->strtab + after->st_name);

	} else if (before) {

		warn("%s - Section mismatch: reference to %s from %s "

		     "after '%s' (at offset 0x%lx)\n",

		     modname, secname, fromsec, 

		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)(r.r_offset - before->st_value));

		     (long long)r.r_offset);

	} else if (after) {

		warn("%s - Section mismatch: reference to %s from %s "

		     "before '%s' (at offset -0x%lx)\n",

		     modname, secname, fromsec, 

		warn("%s - Section mismatch: reference to %s:%s from %s "

		     "before '%s' (at offset -0x%llx)\n",

		     modname, secname, refsymname, fromsec, 

		     elf->strtab + before->st_name,

		     (long)(before->st_value - r.r_offset));

		     (long long)r.r_offset);

	} else {

		warn("%s - Section mismatch: reference to %s from %s "

		     "(offset 0x%lx)\n",

		     modname, secname, fromsec, (long)r.r_offset);

		warn("%s - Section mismatch: reference to %s:%s from %s "

		     "(offset 0x%llx)\n",

		     modname, secname, fromsec, refsymname,

		     (long long)r.r_offset);

	}

}
@@ -575,6 +604,7 @@ static void check_sec_ref(struct module *mod, const char *modname, 
			const char *secname;

			r.r_offset = TO_NATIVE(rela->r_offset);

			r.r_info   = TO_NATIVE(rela->r_info);

			r.r_addend = TO_NATIVE(rela->r_addend);

			sym = elf->symtab_start + ELF_R_SYM(r.r_info);

			/* Skip special sections */

			if (sym->st_shndx >= SHN_LORESERVE)