Eric Lee / linux-smarc-t335x-v3.2

Commit 5aea50b5c76b07f2b6bda3426dba998156eaf6d0

Authored by Arjan van de Ven 2009-01-07 06:40:57 +0800

Committed by Linus Torvalds 2009-01-07 07:59:12 +0800

Exists in master and in 4 other branches

scripts: script from kerneloops.org to pretty print oops dumps

We're struggling all the time to figure out where the code came from that
oopsed..  The script below (a adaption from a script used by
kerneloops.org) can help developers quite a bit, at least for non-module
cases.

It works and looks like this:

[/home/arjan/linux]$ dmesg | perl scripts/markup_oops.pl vmlinux
 {
 	struct agp_memory *memory;

 	memory = agp_allocate_memory(agp_bridge, pg_count, type);
 c055c10f:	89 c2                	mov    %eax,%edx
 	if (memory == NULL)
 c055c111:	74 19                	je     c055c12c <agp_allocate_memory_wrap+0x30>
 /* This function must only be called when current_controller != NULL */
 static void agp_insert_into_pool(struct agp_memory * temp)
 {
 	struct agp_memory *prev;

 	prev = agp_fe.current_controller->pool;
 c055c113:	a1 ec dc 8f c0       	mov    0xc08fdcec,%eax
*c055c118:	8b 40 10             	mov    0x10(%eax),%eax     <----- faulting instruction

 	if (prev != NULL) {
 c055c11b:	85 c0                	test   %eax,%eax
 c055c11d:	74 05                	je     c055c124 <agp_allocate_memory_wrap+0x28>
 		prev->prev = temp;
 c055c11f:	89 50 04             	mov    %edx,0x4(%eax)
 		temp->next = prev;
 c055c122:	89 02                	mov    %eax,(%edx)
 	}
 	agp_fe.current_controller->pool = temp;
 c055c124:	a1 ec dc 8f c0       	mov    0xc08fdcec,%eax
 c055c129:	89 50 10             	mov    %edx,0x10(%eax)
 	if (memory == NULL)
 		return NULL;

 	agp_insert_into_pool(memory);

so in this case, we faulted while dereferencing agp_fe.current_controller
pointer, and we get to see exactly which function and line it affects...
Personally I find this very useful, and I can see value for having this
script in the kernel for more-than-just-me to use.

Caveats:
* It only works for oopses not-in-modules
* It only works nicely for kernels compiled with CONFIG_DEBUG_INFO
* It's not very fast.
* It only works on x86

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Showing 1 changed file with 162 additions and 0 deletions Side-by-side Diff

scripts/markup_oops.pl

scripts/markup_oops.pl

Diff comments View file @ 5aea50b

	1	+#!/usr/bin/perl -w
	2	+
	3	+# Copyright 2008, Intel Corporation
	4	+#
	5	+# This file is part of the Linux kernel
	6	+#
	7	+# This program file is free software; you can redistribute it and/or modify it
	8	+# under the terms of the GNU General Public License as published by the
	9	+# Free Software Foundation; version 2 of the License.
	10	+#
	11	+# Authors:
	12	+# Arjan van de Ven <arjan@linux.intel.com>
	13	+
	14	+
	15	+my $vmlinux_name = $ARGV[0];
	16	+
	17	+#
	18	+# Step 1: Parse the oops to find the EIP value
	19	+#
	20	+
	21	+my $target = "0";
	22	+while (<STDIN>) {
	23	+ if ($_ =~ /EIP: 0060:\[\<([a-z0-9]+)\>\]/) {
	24	+ $target = $1;
	25	+ }
	26	+}
	27	+
	28	+if ($target =~ /^f8/) {
	29	+ print "This script does not work on modules ... \n";
	30	+ exit;
	31	+}
	32	+
	33	+if ($target eq "0") {
	34	+ print "No oops found!\n";
	35	+ print "Usage: \n";
	36	+ print " dmesg \| perl scripts/markup_oops.pl vmlinux\n";
	37	+ exit;
	38	+}
	39	+
	40	+my $counter = 0;
	41	+my $state = 0;
	42	+my $center = 0;
	43	+my @lines;
	44	+
	45	+sub InRange {
	46	+ my ($address, $target) = @_;
	47	+ my $ad = "0x".$address;
	48	+ my $ta = "0x".$target;
	49	+ my $delta = hex($ad) - hex($ta);
	50	+
	51	+ if (($delta > -4096) && ($delta < 4096)) {
	52	+ return 1;
	53	+ }
	54	+ return 0;
	55	+}
	56	+
	57	+
	58	+
	59	+# first, parse the input into the lines array, but to keep size down,
	60	+# we only do this for 4Kb around the sweet spot
	61	+
	62	+my $filename;
	63	+
	64	+open(FILE, "objdump -dS $vmlinux_name \|") \|\| die "Cannot start objdump";
	65	+
	66	+while (<FILE>) {
	67	+ my $line = $_;
	68	+ chomp($line);
	69	+ if ($state == 0) {
	70	+ if ($line =~ /^([a-f0-9]+)\:/) {
	71	+ if (InRange($1, $target)) {
	72	+ $state = 1;
	73	+ }
	74	+ }
	75	+ } else {
	76	+ if ($line =~ /^([a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9]+)\:/) {
	77	+ my $val = $1;
	78	+ if (!InRange($val, $target)) {
	79	+ last;
	80	+ }
	81	+ if ($val eq $target) {
	82	+ $center = $counter;
	83	+ }
	84	+ }
	85	+ $lines[$counter] = $line;
	86	+
	87	+ $counter = $counter + 1;
	88	+ }
	89	+}
	90	+
	91	+close(FILE);
	92	+
	93	+if ($counter == 0) {
	94	+ print "No matching code found \n";
	95	+ exit;
	96	+}
	97	+
	98	+if ($center == 0) {
	99	+ print "No matching code found \n";
	100	+ exit;
	101	+}
	102	+
	103	+my $start;
	104	+my $finish;
	105	+my $codelines = 0;
	106	+my $binarylines = 0;
	107	+# now we go up and down in the array to find how much we want to print
	108	+
	109	+$start = $center;
	110	+
	111	+while ($start > 1) {
	112	+ $start = $start - 1;
	113	+ my $line = $lines[$start];
	114	+ if ($line =~ /^([a-f0-9]+)\:/) {
	115	+ $binarylines = $binarylines + 1;
	116	+ } else {
	117	+ $codelines = $codelines + 1;
	118	+ }
	119	+ if ($codelines > 10) {
	120	+ last;
	121	+ }
	122	+ if ($binarylines > 20) {
	123	+ last;
	124	+ }
	125	+}
	126	+
	127	+
	128	+$finish = $center;
	129	+$codelines = 0;
	130	+$binarylines = 0;
	131	+while ($finish < $counter) {
	132	+ $finish = $finish + 1;
	133	+ my $line = $lines[$finish];
	134	+ if ($line =~ /^([a-f0-9]+)\:/) {
	135	+ $binarylines = $binarylines + 1;
	136	+ } else {
	137	+ $codelines = $codelines + 1;
	138	+ }
	139	+ if ($codelines > 10) {
	140	+ last;
	141	+ }
	142	+ if ($binarylines > 20) {
	143	+ last;
	144	+ }
	145	+}
	146	+
	147	+
	148	+my $i;
	149	+
	150	+my $fulltext = "";
	151	+$i = $start;
	152	+while ($i < $finish) {
	153	+ if ($i == $center) {
	154	+ $fulltext = $fulltext . "*$lines[$i] <----- faulting instruction\n";
	155	+ } else {
	156	+ $fulltext = $fulltext . " $lines[$i]\n";
	157	+ }
	158	+ $i = $i +1;
	159	+}
	160	+
	161	+print $fulltext;