scripts/markup_oops.pl

   1 #!/usr/bin/env perl
   2
   3 use File::Basename;
   4 use Math::BigInt;
   5 use Getopt::Long;
   6
   7 # Copyright 2008, Intel Corporation
   8 #
   9 # This file is part of the Linux kernel
  10 #
  11 # This program file is free software; you can redistribute it and/or modify it
  12 # under the terms of the GNU General Public License as published by the
  13 # Free Software Foundation; version 2 of the License.
  14 #
  15 # Authors:
  16 #       Arjan van de Ven <arjan@linux.intel.com>
  17
  18
  19 my $cross_compile = "";
  20 my $vmlinux_name = "";
  21 my $modulefile = "";
  22
  23 # Get options
  24 Getopt::Long::GetOptions(
  25         'cross-compile|c=s'     => \$cross_compile,
  26         'module|m=s'            => \$modulefile,
  27         'help|h'                => \&usage,
  28 ) || usage ();
  29 my $vmlinux_name = $ARGV[0];
  30 if (!defined($vmlinux_name)) {
  31         my $kerver = `uname -r`;
  32         chomp($kerver);
  33         $vmlinux_name = "/lib/modules/$kerver/build/vmlinux";
  34         print "No vmlinux specified, assuming $vmlinux_name\n";
  35 }
  36 my $filename = $vmlinux_name;
  37
  38 # Parse the oops to find the EIP value
  39
  40 my $target = "0";
  41 my $function;
  42 my $module = "";
  43 my $func_offset = 0;
  44 my $vmaoffset = 0;
  45
  46 my %regs;
  47
  48
  49 sub parse_x86_regs
  50 {
  51         my ($line) = @_;
  52         if ($line =~ /EAX: ([0-9a-f]+) EBX: ([0-9a-f]+) ECX: ([0-9a-f]+) EDX: ([0-9a-f]+)/) {
  53                 $regs{"%eax"} = $1;
  54                 $regs{"%ebx"} = $2;
  55                 $regs{"%ecx"} = $3;
  56                 $regs{"%edx"} = $4;
  57         }
  58         if ($line =~ /ESI: ([0-9a-f]+) EDI: ([0-9a-f]+) EBP: ([0-9a-f]+) ESP: ([0-9a-f]+)/) {
  59                 $regs{"%esi"} = $1;
  60                 $regs{"%edi"} = $2;
  61                 $regs{"%esp"} = $4;
  62         }
  63         if ($line =~ /RAX: ([0-9a-f]+) RBX: ([0-9a-f]+) RCX: ([0-9a-f]+)/) {
  64                 $regs{"%eax"} = $1;
  65                 $regs{"%ebx"} = $2;
  66                 $regs{"%ecx"} = $3;
  67         }
  68         if ($line =~ /RDX: ([0-9a-f]+) RSI: ([0-9a-f]+) RDI: ([0-9a-f]+)/) {
  69                 $regs{"%edx"} = $1;
  70                 $regs{"%esi"} = $2;
  71                 $regs{"%edi"} = $3;
  72         }
  73         if ($line =~ /RBP: ([0-9a-f]+) R08: ([0-9a-f]+) R09: ([0-9a-f]+)/) {
  74                 $regs{"%r08"} = $2;
  75                 $regs{"%r09"} = $3;
  76         }
  77         if ($line =~ /R10: ([0-9a-f]+) R11: ([0-9a-f]+) R12: ([0-9a-f]+)/) {
  78                 $regs{"%r10"} = $1;
  79                 $regs{"%r11"} = $2;
  80                 $regs{"%r12"} = $3;
  81         }
  82         if ($line =~ /R13: ([0-9a-f]+) R14: ([0-9a-f]+) R15: ([0-9a-f]+)/) {
  83                 $regs{"%r13"} = $1;
  84                 $regs{"%r14"} = $2;
  85                 $regs{"%r15"} = $3;
  86         }
  87 }
  88
  89 sub reg_name
  90 {
  91         my ($reg) = @_;
  92         $reg =~ s/r(.)x/e\1x/;
  93         $reg =~ s/r(.)i/e\1i/;
  94         $reg =~ s/r(.)p/e\1p/;
  95         return $reg;
  96 }
  97
  98 sub process_x86_regs
  99 {
 100         my ($line, $cntr) = @_;
 101         my $str = "";
 102         if (length($line) < 40) {
 103                 return ""; # not an asm istruction
 104         }
 105
 106         # find the arguments to the instruction
 107         if ($line =~ /([0-9a-zA-Z\,\%\(\)\-\+]+)$/) {
 108                 $lastword = $1;
 109         } else {
 110                 return "";
 111         }
 112
 113         # we need to find the registers that get clobbered,
 114         # since their value is no longer relevant for previous
 115         # instructions in the stream.
 116
 117         $clobber = $lastword;
 118         # first, remove all memory operands, they're read only
 119         $clobber =~ s/\([a-z0-9\%\,]+\)//g;
 120         # then, remove everything before the comma, thats the read part
 121         $clobber =~ s/.*\,//g;
 122
 123         # if this is the instruction that faulted, we haven't actually done
 124         # the write yet... nothing is clobbered.
 125         if ($cntr == 0) {
 126                 $clobber = "";
 127         }
 128
 129         foreach $reg (keys(%regs)) {
 130                 my $clobberprime = reg_name($clobber);
 131                 my $lastwordprime = reg_name($lastword);
 132                 my $val = $regs{$reg};
 133                 if ($val =~ /^[0]+$/) {
 134                         $val = "0";
 135                 } else {
 136                         $val =~ s/^0*//;
 137                 }
 138
 139                 # first check if we're clobbering this register; if we do
 140                 # we print it with a =>, and then delete its value
 141                 if ($clobber =~ /$reg/ || $clobberprime =~ /$reg/) {
 142                         if (length($val) > 0) {
 143                                 $str = $str . " $reg => $val ";
 144                         }
 145                         $regs{$reg} = "";
 146                         $val = "";
 147                 }
 148                 # now check if we're reading this register
 149                 if ($lastword =~ /$reg/ || $lastwordprime =~ /$reg/) {
 150                         if (length($val) > 0) {
 151                                 $str = $str . " $reg = $val ";
 152                         }
 153                 }
 154         }
 155         return $str;
 156 }
 157
 158 # parse the oops
 159 while (<STDIN>) {
 160         my $line = $_;
 161         if ($line =~ /EIP: 0060:\[\<([a-z0-9]+)\>\]/) {
 162                 $target = $1;
 163         }
 164         if ($line =~ /RIP: 0010:\[\<([a-z0-9]+)\>\]/) {
 165                 $target = $1;
 166         }
 167         if ($line =~ /EIP is at ([a-zA-Z0-9\_]+)\+0x([0-9a-f]+)\/0x[a-f0-9]/) {
 168                 $function = $1;
 169                 $func_offset = $2;
 170         }
 171         if ($line =~ /RIP: 0010:\[\<[0-9a-f]+\>\]  \[\<[0-9a-f]+\>\] ([a-zA-Z0-9\_]+)\+0x([0-9a-f]+)\/0x[a-f0-9]/) {
 172                 $function = $1;
 173                 $func_offset = $2;
 174         }
 175
 176         # check if it's a module
 177         if ($line =~ /EIP is at ([a-zA-Z0-9\_]+)\+(0x[0-9a-f]+)\/0x[a-f0-9]+\W\[([a-zA-Z0-9\_\-]+)\]/) {
 178                 $module = $3;
 179         }
 180         if ($line =~ /RIP: 0010:\[\<[0-9a-f]+\>\]  \[\<[0-9a-f]+\>\] ([a-zA-Z0-9\_]+)\+(0x[0-9a-f]+)\/0x[a-f0-9]+\W\[([a-zA-Z0-9\_\-]+)\]/) {
 181                 $module = $3;
 182         }
 183         parse_x86_regs($line);
 184 }
 185
 186 my $decodestart = Math::BigInt->from_hex("0x$target") - Math::BigInt->from_hex("0x$func_offset");
 187 my $decodestop = Math::BigInt->from_hex("0x$target") + 8192;
 188 if ($target eq "0") {
 189         print "No oops found!\n";
 190         usage();
 191 }
 192
 193 # if it's a module, we need to find the .ko file and calculate a load offset
 194 if ($module ne "") {
 195         if ($modulefile eq "") {
 196                 $modulefile = `modinfo -F filename $module`;
 197                 chomp($modulefile);
 198         }
 199         $filename = $modulefile;
 200         if ($filename eq "") {
 201                 print "Module .ko file for $module not found. Aborting\n";
 202                 exit;
 203         }
 204         # ok so we found the module, now we need to calculate the vma offset
 205         open(FILE, $cross_compile."objdump -dS $filename |") || die "Cannot start objdump";
 206         while (<FILE>) {
 207                 if ($_ =~ /^([0-9a-f]+) \<$function\>\:/) {
 208                         my $fu = $1;
 209                         $vmaoffset = Math::BigInt->from_hex("0x$target") - Math::BigInt->from_hex("0x$fu") - Math::BigInt->from_hex("0x$func_offset");
 210                 }
 211         }
 212         close(FILE);
 213 }
 214
 215 my $counter = 0;
 216 my $state   = 0;
 217 my $center  = -1;
 218 my @lines;
 219 my @reglines;
 220
 221 sub InRange {
 222         my ($address, $target) = @_;
 223         my $ad = "0x".$address;
 224         my $ta = "0x".$target;
 225         my $delta = Math::BigInt->from_hex($ad) - Math::BigInt->from_hex($ta);
 226
 227         if (($delta > -4096) && ($delta < 4096)) {
 228                 return 1;
 229         }
 230         return 0;
 231 }
 232
 233
 234
 235 # first, parse the input into the lines array, but to keep size down,
 236 # we only do this for 4Kb around the sweet spot
 237
 238 open(FILE, $cross_compile."objdump -dS --adjust-vma=$vmaoffset --start-address=$decodestart --stop-address=$decodestop $filename |") || die "Cannot start objdump";
 239
 240 while (<FILE>) {
 241         my $line = $_;
 242         chomp($line);
 243         if ($state == 0) {
 244                 if ($line =~ /^([a-f0-9]+)\:/) {
 245                         if (InRange($1, $target)) {
 246                                 $state = 1;
 247                         }
 248                 }
 249         }
 250         if ($state == 1) {
 251                 if ($line =~ /^([a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9]+)\:/) {
 252                         my $val = $1;
 253                         if (!InRange($val, $target)) {
 254                                 last;
 255                         }
 256                         if ($val eq $target) {
 257                                 $center = $counter;
 258                         }
 259                 }
 260                 $lines[$counter] = $line;
 261
 262                 $counter = $counter + 1;
 263         }
 264 }
 265
 266 close(FILE);
 267
 268 if ($counter == 0) {
 269         print "No matching code found \n";
 270         exit;
 271 }
 272
 273 if ($center == -1) {
 274         print "No matching code found \n";
 275         exit;
 276 }
 277
 278 my $start;
 279 my $finish;
 280 my $codelines = 0;
 281 my $binarylines = 0;
 282 # now we go up and down in the array to find how much we want to print
 283
 284 $start = $center;
 285
 286 while ($start > 1) {
 287         $start = $start - 1;
 288         my $line = $lines[$start];
 289         if ($line =~ /^([a-f0-9]+)\:/) {
 290                 $binarylines = $binarylines + 1;
 291         } else {
 292                 $codelines = $codelines + 1;
 293         }
 294         if ($codelines > 10) {
 295                 last;
 296         }
 297         if ($binarylines > 20) {
 298                 last;
 299         }
 300 }
 301
 302
 303 $finish = $center;
 304 $codelines = 0;
 305 $binarylines = 0;
 306 while ($finish < $counter) {
 307         $finish = $finish + 1;
 308         my $line = $lines[$finish];
 309         if ($line =~ /^([a-f0-9]+)\:/) {
 310                 $binarylines = $binarylines + 1;
 311         } else {
 312                 $codelines = $codelines + 1;
 313         }
 314         if ($codelines > 10) {
 315                 last;
 316         }
 317         if ($binarylines > 20) {
 318                 last;
 319         }
 320 }
 321
 322
 323 my $i;
 324
 325
 326 # start annotating the registers in the asm.
 327 # this goes from the oopsing point back, so that the annotator
 328 # can track (opportunistically) which registers got written and
 329 # whos value no longer is relevant.
 330
 331 $i = $center;
 332 while ($i >= $start) {
 333         $reglines[$i] = process_x86_regs($lines[$i], $center - $i);
 334         $i = $i - 1;
 335 }
 336
 337 $i = $start;
 338 while ($i < $finish) {
 339         my $line;
 340         if ($i == $center) {
 341                 $line =  "*$lines[$i] ";
 342         } else {
 343                 $line =  " $lines[$i] ";
 344         }
 345         print $line;
 346         if (defined($reglines[$i]) && length($reglines[$i]) > 0) {
 347                 my $c = 60 - length($line);
 348                 while ($c > 0) { print " "; $c = $c - 1; };
 349                 print "| $reglines[$i]";
 350         }
 351         if ($i == $center) {
 352                 print "<--- faulting instruction";
 353         }
 354         print "\n";
 355         $i = $i +1;
 356 }
 357
 358 sub usage {
 359         print <<EOT;
 360 Usage:
 361   dmesg | perl $0 [OPTION] [VMLINUX]
 362
 363 OPTION:
 364   -c, --cross-compile CROSS_COMPILE     Specify the prefix used for toolchain.
 365   -m, --module MODULE_DIRNAME           Specify the module filename.
 366   -h, --help                            Help.
 367 EOT
 368         exit;
 369 }