diff options
| -rw-r--r-- | arch/powerpc/kernel/Makefile | 9 | ||||
| -rw-r--r-- | arch/powerpc/kernel/prom_init_check.sh | 58 |
2 files changed, 67 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/Makefile b/arch/powerpc/kernel/Makefile index ce1e8d24e74..9177b21b1a9 100644 --- a/arch/powerpc/kernel/Makefile +++ b/arch/powerpc/kernel/Makefile @@ -106,4 +106,13 @@ PHONY += systbl_chk systbl_chk: $(src)/systbl_chk.sh $(obj)/systbl_chk.i $(call cmd,systbl_chk) +$(obj)/built-in.o: prom_init_check + +quiet_cmd_prom_init_check = CALL $< + cmd_prom_init_check = $(CONFIG_SHELL) $< "$(NM)" "$(obj)/prom_init.o" + +PHONY += prom_init_check +prom_init_check: $(src)/prom_init_check.sh $(obj)/prom_init.o + $(call cmd,prom_init_check) + clean-files := vmlinux.lds diff --git a/arch/powerpc/kernel/prom_init_check.sh b/arch/powerpc/kernel/prom_init_check.sh new file mode 100644 index 00000000000..8e24fc1821e --- /dev/null +++ b/arch/powerpc/kernel/prom_init_check.sh @@ -0,0 +1,58 @@ +#!/bin/sh +# +# Copyright © 2008 IBM Corporation +# +# This program is free software; you can redistribute it and/or +# modify it under the terms of the GNU General Public License +# as published by the Free Software Foundation; either version +# 2 of the License, or (at your option) any later version. + +# This script checks prom_init.o to see what external symbols it +# is using, if it finds symbols not in the whitelist it returns +# an error. The point of this is to discourage people from +# intentionally or accidentally adding new code to prom_init.c +# which has side effects on other parts of the kernel. + +# If you really need to reference something from prom_init.o add +# it to the list below: + +WHITELIST="add_reloc_offset __bss_start __bss_stop copy_and_flush +_end enter_prom memcpy memset reloc_offset __secondary_hold +__secondary_hold_acknowledge __secondary_hold_spinloop __start +strcmp strcpy strlcpy strlen strncmp strstr logo_linux_clut224 +reloc_got2" + +NM="$1" +OBJ="$2" + +ERROR=0 + +for UNDEF in $($NM -u $OBJ | awk '{print $2}') +do + # On 64-bit nm gives us the function descriptors, which have + # a leading . on the name, so strip it off here. + UNDEF="${UNDEF#.}" + + if [ $KBUILD_VERBOSE ]; then + if [ $KBUILD_VERBOSE -ne 0 ]; then + echo "Checking prom_init.o symbol '$UNDEF'" + fi + fi + + OK=0 + for WHITE in $WHITELIST + do + if [ "$UNDEF" = "$WHITE" ]; then + OK=1 + break + fi + done + + if [ $OK -eq 0 ]; then + ERROR=1 + echo "Error: External symbol '$UNDEF' referenced" \ + "from prom_init.c" >&2 + fi +done + +exit $ERROR |