linux/arch/powerpc/relocs_check.pl
Suzuki Poulose 9c5f7d39a8 powerpc: Process dynamic relocations for kernel
The following patch implements the dynamic relocation processing for
PPC32 kernel. relocate() accepts the target virtual address and relocates
 the kernel image to the same.

Currently the following relocation types are handled :

	R_PPC_RELATIVE
	R_PPC_ADDR16_LO
	R_PPC_ADDR16_HI
	R_PPC_ADDR16_HA

The last 3 relocations in the above list depends on value of Symbol indexed
whose index is encoded in the Relocation entry. Hence we need the Symbol
Table for processing such relocations.

Note: The GNU ld for ppc32 produces buggy relocations for relocation types
that depend on symbols. The value of the symbols with STB_LOCAL scope
should be assumed to be zero. - Alan Modra

Signed-off-by: Suzuki K. Poulose <suzuki@in.ibm.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@linux.vnet.ibm.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Alan Modra <amodra@au1.ibm.com>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: linuxppc-dev <linuxppc-dev@lists.ozlabs.org>
Signed-off-by: Josh Boyer <jwboyer@gmail.com>
2011-12-20 10:21:08 -05:00

67 lines
1.6 KiB
Perl
Executable File

#!/usr/bin/perl
# Copyright © 2009 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 the relcoations of a vmlinux for "suspicious"
# relocations.
use strict;
use warnings;
if ($#ARGV != 1) {
die "$0 [path to objdump] [path to vmlinux]\n";
}
# Have Kbuild supply the path to objdump so we handle cross compilation.
my $objdump = shift;
my $vmlinux = shift;
my $bad_relocs_count = 0;
my $bad_relocs = "";
my $old_binutils = 0;
open(FD, "$objdump -R $vmlinux|") or die;
while (<FD>) {
study $_;
# Only look at relcoation lines.
next if (!/\s+R_/);
# These relocations are okay
# On PPC64:
# R_PPC64_RELATIVE, R_PPC64_NONE, R_PPC64_ADDR64
# On PPC:
# R_PPC_RELATIVE, R_PPC_ADDR16_HI,
# R_PPC_ADDR16_HA,R_PPC_ADDR16_LO,
# R_PPC_NONE
next if (/\bR_PPC64_RELATIVE\b/ or /\bR_PPC64_NONE\b/ or
/\bR_PPC64_ADDR64\s+mach_/);
next if (/\bR_PPC_ADDR16_LO\b/ or /\bR_PPC_ADDR16_HI\b/ or
/\bR_PPC_ADDR16_HA\b/ or /\bR_PPC_RELATIVE\b/ or
/\bR_PPC_NONE\b/);
# If we see this type of relcoation it's an idication that
# we /may/ be using an old version of binutils.
if (/R_PPC64_UADDR64/) {
$old_binutils++;
}
$bad_relocs_count++;
$bad_relocs .= $_;
}
if ($bad_relocs_count) {
print "WARNING: $bad_relocs_count bad relocations\n";
print $bad_relocs;
}
if ($old_binutils) {
print "WARNING: You need at binutils >= 2.19 to build a ".
"CONFIG_RELCOATABLE kernel\n";
}