[PATCH] Add reference_init.pl to `make buildcheck' target

`make buildcheck' only checks for calls to linker discarded sections,

reference_init checks for calls to sections discarded at run time, init was
cloned from discarded.  They are separate because the linker detects the
discarded case and I did not want to confuse users with messages about init
text/data while they were fixing the linker errors.

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/scripts/reference_discarded.pl b/scripts/reference_discarded.pl
index 9d01ec5f30b7baac60e3d5c5bbd6b30511fd2167..8f80364fc2804934c08c6e90a0b4cc6b3bcebb0b 100644 (file)
--- a/scripts/reference_discarded.pl
+++ b/scripts/reference_discarded.pl
@@ -106,4 +106,4 @@ foreach $object (keys(%object)) {
 }
 # printf("Done\n");
 
-exit($errorcount);
+exit(0);

diff --git a/scripts/reference_init.pl b/scripts/reference_init.pl
new file mode 100644 (file)
index 0000000..b4e37dc
--- /dev/null
+++ b/scripts/reference_init.pl
@@ -0,0 +1,102 @@
+#!/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) {
+                       ++$ignore;
+                       delete($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 !~ /\.debug_/)) {
+                       printf("Error: %s %s refers to %s\n", $object, $from, $line);
+               }
+       }
+       close(OBJDUMP);
+}
+printf("Done\n");