blob: ea3a2ec03ffafe1a00a946895ee77db5c39b650d [file] [log] [blame]
Michael Ellerman5c02cd22008-04-24 12:08:22 +10001#!/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
Kumar Galaa3ba68f2008-10-20 03:16:55 +000023reloc_got2 kernstart_addr memstart_addr"
Michael Ellerman5c02cd22008-04-24 12:08:22 +100024
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" = "$WHITE" ]; then
46 OK=1
47 break
48 fi
49 done
50
Kumar Galada3de6d2008-06-13 07:20:58 +100051 # ignore register save/restore funcitons
52 if [ "${UNDEF:0:9}" = "_restgpr_" ]; then
53 OK=1
54 fi
55 if [ "${UNDEF:0:11}" = "_rest32gpr_" ]; then
56 OK=1
57 fi
58 if [ "${UNDEF:0:9}" = "_savegpr_" ]; then
59 OK=1
60 fi
61 if [ "${UNDEF:0:11}" = "_save32gpr_" ]; then
62 OK=1
63 fi
64
Michael Ellerman5c02cd22008-04-24 12:08:22 +100065 if [ $OK -eq 0 ]; then
66 ERROR=1
67 echo "Error: External symbol '$UNDEF' referenced" \
68 "from prom_init.c" >&2
69 fi
70done
71
72exit $ERROR