1#!/bin/sh 2# 3# Copyright © 2008 IBM Corporation 4# 5# This program is free software; you can redistribute it and/or 6# modify it under the terms of the GNU General Public License 7# as published by the Free Software Foundation; either version 8# 2 of the License, or (at your option) any later version. 9 10# This script checks prom_init.o to see what external symbols it 11# is using, if it finds symbols not in the whitelist it returns 12# an error. The point of this is to discourage people from 13# intentionally or accidentally adding new code to prom_init.c 14# which has side effects on other parts of the kernel. 15 16# If you really need to reference something from prom_init.o add 17# it to the list below: 18 19WHITELIST="add_reloc_offset __bss_start __bss_stop copy_and_flush 20_end enter_prom memcpy memset reloc_offset __secondary_hold 21__secondary_hold_acknowledge __secondary_hold_spinloop __start 22strcmp strcpy strlcpy strlen strncmp strstr logo_linux_clut224 23reloc_got2" 24 25NM="$1" 26OBJ="$2" 27 28ERROR=0 29 30for UNDEF in $($NM -u $OBJ | awk '{print $2}') 31do 32 # On 64-bit nm gives us the function descriptors, which have 33 # a leading . on the name, so strip it off here. 34 UNDEF="${UNDEF#.}" 35 36 if [ $KBUILD_VERBOSE ]; then 37 if [ $KBUILD_VERBOSE -ne 0 ]; then 38 echo "Checking prom_init.o symbol '$UNDEF'" 39 fi 40 fi 41 42 OK=0 43 for WHITE in $WHITELIST 44 do 45 if [ "$UNDEF" = "$WHITE" ]; then 46 OK=1 47 break 48 fi 49 done 50 51 if [ $OK -eq 0 ]; then 52 ERROR=1 53 echo "Error: External symbol '$UNDEF' referenced" \ 54 "from prom_init.c" >&2 55 fi 56done 57 58exit $ERROR 59