Michael Ellerman | 5c02cd2 | 2008-04-24 12:08:22 +1000 | [diff] [blame] | 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 | |
| 19 | WHITELIST="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 |
| 22 | strcmp strcpy strlcpy strlen strncmp strstr logo_linux_clut224 |
Benjamin Herrenschmidt | 27f44888 | 2011-09-19 18:27:58 +0000 | [diff] [blame] | 23 | reloc_got2 kernstart_addr memstart_addr linux_banner _stext |
Michael Ellerman | e2500be | 2014-06-24 17:17:47 +1000 | [diff] [blame] | 24 | __prom_init_toc_start __prom_init_toc_end btext_setup_display TOC." |
Michael Ellerman | 5c02cd2 | 2008-04-24 12:08:22 +1000 | [diff] [blame] | 25 | |
| 26 | NM="$1" |
| 27 | OBJ="$2" |
| 28 | |
| 29 | ERROR=0 |
| 30 | |
| 31 | for UNDEF in $($NM -u $OBJ | awk '{print $2}') |
| 32 | do |
| 33 | # On 64-bit nm gives us the function descriptors, which have |
| 34 | # a leading . on the name, so strip it off here. |
| 35 | UNDEF="${UNDEF#.}" |
| 36 | |
| 37 | if [ $KBUILD_VERBOSE ]; then |
| 38 | if [ $KBUILD_VERBOSE -ne 0 ]; then |
| 39 | echo "Checking prom_init.o symbol '$UNDEF'" |
| 40 | fi |
| 41 | fi |
| 42 | |
| 43 | OK=0 |
| 44 | for WHITE in $WHITELIST |
| 45 | do |
| 46 | if [ "$UNDEF" = "$WHITE" ]; then |
| 47 | OK=1 |
| 48 | break |
| 49 | fi |
| 50 | done |
| 51 | |
Kumar Gala | da3de6d | 2008-06-13 07:20:58 +1000 | [diff] [blame] | 52 | # ignore register save/restore funcitons |
Andreas Schwab | fe921c8 | 2014-09-13 10:20:17 +0200 | [diff] [blame] | 53 | case $UNDEF in |
| 54 | _restgpr_*|_restgpr0_*|_rest32gpr_*) |
Kumar Gala | da3de6d | 2008-06-13 07:20:58 +1000 | [diff] [blame] | 55 | OK=1 |
Andreas Schwab | fe921c8 | 2014-09-13 10:20:17 +0200 | [diff] [blame] | 56 | ;; |
| 57 | _savegpr_*|_savegpr0_*|_save32gpr_*) |
Stephen Rothwell | 5afd878 | 2010-06-29 20:04:22 +0000 | [diff] [blame] | 58 | OK=1 |
Andreas Schwab | fe921c8 | 2014-09-13 10:20:17 +0200 | [diff] [blame] | 59 | ;; |
| 60 | esac |
Kumar Gala | da3de6d | 2008-06-13 07:20:58 +1000 | [diff] [blame] | 61 | |
Michael Ellerman | 5c02cd2 | 2008-04-24 12:08:22 +1000 | [diff] [blame] | 62 | if [ $OK -eq 0 ]; then |
| 63 | ERROR=1 |
| 64 | echo "Error: External symbol '$UNDEF' referenced" \ |
| 65 | "from prom_init.c" >&2 |
| 66 | fi |
| 67 | done |
| 68 | |
| 69 | exit $ERROR |