1 files changed, 107 insertions, 0 deletions

diff --git a/scripts/reference_init.pl b/scripts/reference_init.pl
new file mode 100644
index 000000000000..9a2408453869
--- /dev/null
+++ b/scripts/reference_init.pl
@@ -0,0 +1,107 @@
+#!/usr/bin/perl -w
+#
+# reference_init.pl (C) Keith Owens 2002 <kaos@ocs.com.au>
+#
+# List references to vmlinux init sections from non-init sections.
+
+# Unfortunately I had to exclude references from read only data to .init
+# sections, almost all of these are false positives, they are created by
+# gcc.  The downside of excluding rodata is that there really are some
+# user references from rodata to init code, e.g. drivers/video/vgacon.c
+#
+# const struct consw vga_con = {
+#        con_startup:            vgacon_startup,
+#
+# where vgacon_startup is __init.  If you want to wade through the false
+# positives, take out the check for rodata.
+
+use strict;
+die($0 . " takes no arguments\n") if($#ARGV >= 0);
+
+my %object;
+my $object;
+my $line;
+my $ignore;
+
+$| = 1;
+
+printf("Finding objects, ");
+open(OBJDUMP_LIST, "find . -name '*.o' | xargs objdump -h |") || die "getting objdump list failed";
+while (defined($line = <OBJDUMP_LIST>)) {
+        chomp($line);
+        if ($line =~ /:\s+file format/) {
+                ($object = $line) =~ s/:.*//;
+                $object{$object}->{'module'} = 0;
+                $object{$object}->{'size'} = 0;
+                $object{$object}->{'off'} = 0;
+        }
+        if ($line =~ /^\s*\d+\s+\.modinfo\s+/) {
+                $object{$object}->{'module'} = 1;
+        }
+        if ($line =~ /^\s*\d+\s+\.comment\s+/) {
+                ($object{$object}->{'size'}, $object{$object}->{'off'}) = (split(' ', $line))[2,5];
+        }
+}
+close(OBJDUMP_LIST);
+printf("%d objects, ", scalar keys(%object));
+$ignore = 0;
+foreach $object (keys(%object)) {
+        if ($object{$object}->{'module'}) {
+                ++$ignore;
+                delete($object{$object});
+        }
+}
+printf("ignoring %d module(s)\n", $ignore);
+
+# Ignore conglomerate objects, they have been built from multiple objects and we
+# only care about the individual objects.  If an object has more than one GCC:
+# string in the comment section then it is conglomerate.  This does not filter
+# out conglomerates that consist of exactly one object, can't be helped.
+
+printf("Finding conglomerates, ");
+$ignore = 0;
+foreach $object (keys(%object)) {
+        if (exists($object{$object}->{'off'})) {
+                my ($off, $size, $comment, $l);
+                $off = hex($object{$object}->{'off'});
+                $size = hex($object{$object}->{'size'});
+                open(OBJECT, "<$object") || die "cannot read $object";
+                seek(OBJECT, $off, 0) || die "seek to $off in $object failed";
+                $l = read(OBJECT, $comment, $size);
+                die "read $size bytes from $object .comment failed" if ($l != $size);
+                close(OBJECT);
+                if ($comment =~ /GCC\:.*GCC\:/m || $object =~ /built-in\.o/) {
+                        ++$ignore;
+                        delete($object{$object});
+                }
+        }
+}
+printf("ignoring %d conglomerate(s)\n", $ignore);
+
+printf("Scanning objects\n");
+foreach $object (sort(keys(%object))) {
+        my $from;
+        open(OBJDUMP, "objdump -r $object|") || die "cannot objdump -r $object";
+        while (defined($line = <OBJDUMP>)) {
+                chomp($line);
+                if ($line =~ /RELOCATION RECORDS FOR /) {
+                        ($from = $line) =~ s/.*\[([^]]*).*/$1/;
+                }
+                if (($line =~ /\.init$/ || $line =~ /\.init\./) &&
+                    ($from !~ /\.init$/ &&
+                     $from !~ /\.init\./ &&
+                     $from !~ /\.stab$/ &&
+                     $from !~ /\.rodata$/ &&
+                     $from !~ /\.text\.lock$/ &&
+                     $from !~ /\.pci_fixup_header$/ &&
+                     $from !~ /\.pci_fixup_final$/ &&
+                     $from !~ /\.pdr$/ &&
+                     $from !~ /\__param$/ &&
+                     $from !~ /\.altinstructions/ &&
+                     $from !~ /\.debug_/)) {
+                        printf("Error: %s %s refers to %s\n", $object, $from, $line);
+                }
+        }
+        close(OBJDUMP);
+}
+printf("Done\n");