scripts/markup_oops.pl

   1 #!/usr/bin/perl -w
   2
   3 use File::Basename;
   4
   5 # Copyright 2008, Intel Corporation
   6 #
   7 # This file is part of the Linux kernel
   8 #
   9 # This program file is free software; you can redistribute it and/or modify it
  10 # under the terms of the GNU General Public License as published by the
  11 # Free Software Foundation; version 2 of the License.
  12 #
  13 # Authors:
  14 #       Arjan van de Ven <arjan@linux.intel.com>
  15
  16
  17 my $vmlinux_name = $ARGV[0];
  18 if (!defined($vmlinux_name)) {
  19         my $kerver = `uname -r`;
  20         chomp($kerver);
  21         $vmlinux_name = "/lib/modules/$kerver/build/vmlinux";
  22         print "No vmlinux specified, assuming $vmlinux_name\n";
  23 }
  24 my $filename = $vmlinux_name;
  25 #
  26 # Step 1: Parse the oops to find the EIP value
  27 #
  28
  29 my $target = "0";
  30 my $function;
  31 my $module = "";
  32 my $func_offset;
  33 my $vmaoffset = 0;
  34
  35 my %regs;
  36
  37
  38 sub parse_x86_regs
  39 {
  40         my ($line) = @_;
  41         if ($line =~ /EAX: ([0-9a-f]+) EBX: ([0-9a-f]+) ECX: ([0-9a-f]+) EDX: ([0-9a-f]+)/) {
  42                 $regs{"%eax"} = $1;
  43                 $regs{"%ebx"} = $2;
  44                 $regs{"%ecx"} = $3;
  45                 $regs{"%edx"} = $4;
  46         }
  47         if ($line =~ /ESI: ([0-9a-f]+) EDI: ([0-9a-f]+) EBP: ([0-9a-f]+) ESP: ([0-9a-f]+)/) {
  48                 $regs{"%esi"} = $1;
  49                 $regs{"%edi"} = $2;
  50                 $regs{"%esp"} = $4;
  51         }
  52 }
  53
  54 sub process_x86_regs
  55 {
  56         my ($line, $cntr) = @_;
  57         my $str = "";
  58         if (length($line) < 40) {
  59                 return ""; # not an asm istruction
  60         }
  61
  62         # find the arguments to the instruction
  63         if ($line =~ /([0-9a-zA-Z\,\%\(\)\-\+]+)$/) {
  64                 $lastword = $1;
  65         } else {
  66                 return "";
  67         }
  68
  69         # we need to find the registers that get clobbered,
  70         # since their value is no longer relevant for previous
  71         # instructions in the stream.
  72
  73         $clobber = $lastword;
  74         # first, remove all memory operands, they're read only
  75         $clobber =~ s/\([a-z0-9\%\,]+\)//g;
  76         # then, remove everything before the comma, thats the read part
  77         $clobber =~ s/.*\,//g;
  78
  79         # if this is the instruction that faulted, we haven't actually done
  80         # the write yet... nothing is clobbered.
  81         if ($cntr == 0) {
  82                 $clobber = "";
  83         }
  84
  85         foreach $reg (keys(%regs)) {
  86                 my $val = $regs{$reg};
  87                 # first check if we're clobbering this register; if we do
  88                 # we print it with a =>, and then delete its value
  89                 if ($clobber =~ /$reg/) {
  90                         if (length($val) > 0) {
  91                                 $str = $str . " $reg => $val ";
  92                         }
  93                         $regs{$reg} = "";
  94                         $val = "";
  95                 }
  96                 # now check if we're reading this register
  97                 if ($lastword =~ /$reg/) {
  98                         if (length($val) > 0) {
  99                                 $str = $str . " $reg = $val ";
 100                         }
 101                 }
 102         }
 103         return $str;
 104 }
 105
 106 # parse the oops
 107 while (<STDIN>) {
 108         my $line = $_;
 109         if ($line =~ /EIP: 0060:\[\<([a-z0-9]+)\>\]/) {
 110                 $target = $1;
 111         }
 112         if ($line =~ /EIP is at ([a-zA-Z0-9\_]+)\+(0x[0-9a-f]+)\/0x[a-f0-9]/) {
 113                 $function = $1;
 114                 $func_offset = $2;
 115         }
 116
 117         # check if it's a module
 118         if ($line =~ /EIP is at ([a-zA-Z0-9\_]+)\+(0x[0-9a-f]+)\/0x[a-f0-9]+\W\[([a-zA-Z0-9\_\-]+)\]/) {
 119                 $module = $3;
 120         }
 121         parse_x86_regs($line);
 122 }
 123
 124 my $decodestart = hex($target) - hex($func_offset);
 125 my $decodestop = hex($target) + 8192;
 126 if ($target eq "0") {
 127         print "No oops found!\n";
 128         print "Usage: \n";
 129         print "    dmesg | perl scripts/markup_oops.pl vmlinux\n";
 130         exit;
 131 }
 132
 133 # if it's a module, we need to find the .ko file and calculate a load offset
 134 if ($module ne "") {
 135         my $dir = dirname($filename);
 136         $dir = $dir . "/";
 137         my $mod = $module . ".ko";
 138         my $modulefile = `find $dir -name $mod | head -1`;
 139         chomp($modulefile);
 140         $filename = $modulefile;
 141         if ($filename eq "") {
 142                 print "Module .ko file for $module not found. Aborting\n";
 143                 exit;
 144         }
 145         # ok so we found the module, now we need to calculate the vma offset
 146         open(FILE, "objdump -dS $filename |") || die "Cannot start objdump";
 147         while (<FILE>) {
 148                 if ($_ =~ /^([0-9a-f]+) \<$function\>\:/) {
 149                         my $fu = $1;
 150                         $vmaoffset = hex($target) - hex($fu) - hex($func_offset);
 151                 }
 152         }
 153         close(FILE);
 154 }
 155
 156 my $counter = 0;
 157 my $state   = 0;
 158 my $center  = 0;
 159 my @lines;
 160 my @reglines;
 161
 162 sub InRange {
 163         my ($address, $target) = @_;
 164         my $ad = "0x".$address;
 165         my $ta = "0x".$target;
 166         my $delta = hex($ad) - hex($ta);
 167
 168         if (($delta > -4096) && ($delta < 4096)) {
 169                 return 1;
 170         }
 171         return 0;
 172 }
 173
 174
 175
 176 # first, parse the input into the lines array, but to keep size down,
 177 # we only do this for 4Kb around the sweet spot
 178
 179 open(FILE, "objdump -dS --adjust-vma=$vmaoffset --start-address=$decodestart --stop-address=$decodestop $filename |") || die "Cannot start objdump";
 180
 181 while (<FILE>) {
 182         my $line = $_;
 183         chomp($line);
 184         if ($state == 0) {
 185                 if ($line =~ /^([a-f0-9]+)\:/) {
 186                         if (InRange($1, $target)) {
 187                                 $state = 1;
 188                         }
 189                 }
 190         } else {
 191                 if ($line =~ /^([a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9]+)\:/) {
 192                         my $val = $1;
 193                         if (!InRange($val, $target)) {
 194                                 last;
 195                         }
 196                         if ($val eq $target) {
 197                                 $center = $counter;
 198                         }
 199                 }
 200                 $lines[$counter] = $line;
 201
 202                 $counter = $counter + 1;
 203         }
 204 }
 205
 206 close(FILE);
 207
 208 if ($counter == 0) {
 209         print "No matching code found \n";
 210         exit;
 211 }
 212
 213 if ($center == 0) {
 214         print "No matching code found \n";
 215         exit;
 216 }
 217
 218 my $start;
 219 my $finish;
 220 my $codelines = 0;
 221 my $binarylines = 0;
 222 # now we go up and down in the array to find how much we want to print
 223
 224 $start = $center;
 225
 226 while ($start > 1) {
 227         $start = $start - 1;
 228         my $line = $lines[$start];
 229         if ($line =~ /^([a-f0-9]+)\:/) {
 230                 $binarylines = $binarylines + 1;
 231         } else {
 232                 $codelines = $codelines + 1;
 233         }
 234         if ($codelines > 10) {
 235                 last;
 236         }
 237         if ($binarylines > 20) {
 238                 last;
 239         }
 240 }
 241
 242
 243 $finish = $center;
 244 $codelines = 0;
 245 $binarylines = 0;
 246 while ($finish < $counter) {
 247         $finish = $finish + 1;
 248         my $line = $lines[$finish];
 249         if ($line =~ /^([a-f0-9]+)\:/) {
 250                 $binarylines = $binarylines + 1;
 251         } else {
 252                 $codelines = $codelines + 1;
 253         }
 254         if ($codelines > 10) {
 255                 last;
 256         }
 257         if ($binarylines > 20) {
 258                 last;
 259         }
 260 }
 261
 262
 263 my $i;
 264
 265
 266 # start annotating the registers in the asm.
 267 # this goes from the oopsing point back, so that the annotator
 268 # can track (opportunistically) which registers got written and
 269 # whos value no longer is relevant.
 270
 271 $i = $center;
 272 while ($i >= $start) {
 273         $reglines[$i] = process_x86_regs($lines[$i], $center - $i);
 274         $i = $i - 1;
 275 }
 276
 277 $i = $start;
 278 while ($i < $finish) {
 279         my $line;
 280         if ($i == $center) {
 281                 $line =  "*$lines[$i] ";
 282         } else {
 283                 $line =  " $lines[$i] ";
 284         }
 285         print $line;
 286         if (defined($reglines[$i]) && length($reglines[$i]) > 0) {
 287                 my $c = 60 - length($line);
 288                 while ($c > 0) { print " "; $c = $c - 1; };
 289                 print "| $reglines[$i]";
 290         }
 291         if ($i == $center) {
 292                 print "<--- faulting instruction";
 293         }
 294         print "\n";
 295         $i = $i +1;
 296 }
 297