Root/scripts/markup_oops.pl

1#!/usr/bin/perl
2
3use File::Basename;
4use Math::BigInt;
5use 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
19my $cross_compile = "";
20my $vmlinux_name = "";
21my $modulefile = "";
22
23# Get options
24Getopt::Long::GetOptions(
25    'cross-compile|c=s' => \$cross_compile,
26    'module|m=s' => \$modulefile,
27    'help|h' => \&usage,
28) || usage ();
29my $vmlinux_name = $ARGV[0];
30if (!defined($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}
36my $filename = $vmlinux_name;
37
38# Parse the oops to find the EIP value
39
40my $target = "0";
41my $function;
42my $module = "";
43my $func_offset = 0;
44my $vmaoffset = 0;
45
46my %regs;
47
48
49sub parse_x86_regs
50{
51    my ($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"} = $3;
86    }
87}
88
89sub reg_name
90{
91    my ($reg) = @_;
92    $reg =~ s/r(.)x/e\1x/;
93    $reg =~ s/r(.)i/e\1i/;
94    $reg =~ s/r(.)p/e\1p/;
95    return $reg;
96}
97
98sub process_x86_regs
99{
100    my ($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
159while (<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
186my $decodestart = Math::BigInt->from_hex("0x$target") - Math::BigInt->from_hex("0x$func_offset");
187my $decodestop = Math::BigInt->from_hex("0x$target") + 8192;
188if ($target eq "0") {
189    print "No oops found!\n";
190    usage();
191}
192
193# if it's a module, we need to find the .ko file and calculate a load offset
194if ($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
215my $counter = 0;
216my $state = 0;
217my $center = -1;
218my @lines;
219my @reglines;
220
221sub InRange {
222    my ($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
238open(FILE, $cross_compile."objdump -dS --adjust-vma=$vmaoffset --start-address=$decodestart --stop-address=$decodestop $filename |") || die "Cannot start objdump";
239
240while (<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 = $counter + 1;
263    }
264}
265
266close(FILE);
267
268if ($counter == 0) {
269    print "No matching code found \n";
270    exit;
271}
272
273if ($center == -1) {
274    print "No matching code found \n";
275    exit;
276}
277
278my $start;
279my $finish;
280my $codelines = 0;
281my $binarylines = 0;
282# now we go up and down in the array to find how much we want to print
283
284$start = $center;
285
286while ($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$binarylines = 0;
306while ($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
323my $i;
324
325
326# start annotating the registers in the asm.
327# this goes from the oopsing point back, so that the annotator
328# can track (opportunistically) which registers got written and
329# whos value no longer is relevant.
330
331$i = $center;
332while ($i >= $start) {
333    $reglines[$i] = process_x86_regs($lines[$i], $center - $i);
334    $i = $i - 1;
335}
336
337$i = $start;
338while ($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
358sub usage {
359    print <<EOT;
360Usage:
361  dmesg | perl $0 [OPTION] [VMLINUX]
362
363OPTION:
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.
367EOT
368    exit;
369}
370
371

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