modpost: show offset from symbol for section mismatch warnings

Currently, modpost only shows the symbol names and section names, so it
repeats the same message if there are multiple relocations in the same
symbol. It is common the relocation spans across multiple instructions.

It is better to show the offset from the symbol.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>

scripts/mod/modpost.c

@@ -1147,8 +1147,8 @@ static void default_mismatch_handler(const char *modname, struct elf_info *elf,
 
 	sec_mismatch_count++;
 
-	warn("%s: section mismatch in reference: %s (section: %s) -> %s (section: %s)\n",
-	     modname, fromsym, fromsec, tosym, tosec);
+	warn("%s: section mismatch in reference: %s+0x%x (section: %s) -> %s (section: %s)\n",
+	     modname, fromsym, (unsigned int)(faddr - from->st_value), fromsec, tosym, tosec);
 
 	if (mismatch->mismatch == EXTABLE_TO_NON_TEXT) {
 		if (match(tosec, mismatch->bad_tosec))