Hi,
I had this script lying around (used on kerneloops.org in a slightly modified form,
where I use a database as input rather than stdin). I think it's a useful tool,
at least I find it extremely useful in turning oopses into an "oh duh yes there"
experience...
I know it's in perl, and I know I suck at writing good perl. So I welcome all feedback I
can get... both on the perl and on the usefulness of having this script.
>From 260d3f2246a4fe92f4ec633db82ab44605654d4f Mon Sep 17 00:00:00 2001
From: Arjan van de Ven <[email protected]>
Date: Wed, 5 Nov 2008 19:00:36 -0800
Subject: [PATCH] scripts: script from kerneloops.org to pretty print oops dumps
We're strugling 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_code.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.
Signed-off-by: Arjan van de Ven <[email protected]>
---
scripts/markup_oops.pl | 165 ++++++++++++++++++++++++++++++++++++++++++++++++
1 files changed, 165 insertions(+), 0 deletions(-)
create mode 100644 scripts/markup_oops.pl
diff --git a/scripts/markup_oops.pl b/scripts/markup_oops.pl
new file mode 100644
index 0000000..c8a2200
--- /dev/null
+++ b/scripts/markup_oops.pl
@@ -0,0 +1,165 @@
+#!/usr/bin/perl -w
+
+# Copyright 2008, Intel Corporation
+#
+# This file is part of the Linux kernel
+#
+# This program file is free software; you can redistribute it and/or modify it
+# under the terms of the GNU General Public License as published by the
+# Free Software Foundation; version 2 of the License.
+#
+# Authors:
+# Arjan van de Ven <[email protected]>
+
+
+my $vmlinux_name = $ARGV[0];
+
+#
+# Step 1: Parse the oops to find the EIP value
+#
+
+my $target = "0";
+while (<STDIN>) {
+ if ($_ =~ /EIP: 0060:\[\<([a-z0-9]+)\>\]/) {
+ $target = $1;
+ }
+}
+
+if ($target =~ /^f8/) {
+ print "This script does not work on modules ... \n";
+ exit;
+}
+
+if ($target eq "0") {
+ print "No oops found!\n";
+ print "Usage: \n";
+ print " dmesg | perl scripts/markup_oops.pl vmlinux\n";
+ exit;
+}
+
+my $counter = 0;
+my $state = 0;
+my $center = 0;
+my @lines;
+
+sub InRange {
+ my ($address, $target) = @_;
+ my $ad = "0x".$address;
+ my $ta = "0x".$target;
+ my $delta = hex($ad) - hex($ta);
+
+ if (($delta > -4096) && ($delta < 4096)) {
+ return 1;
+ }
+ return 0;
+}
+
+
+
+# first, parse the input into the lines array, but to keep size down,
+# we only do this for 4Kb around the sweet spot
+
+my $filename;
+
+open(FILE, "objdump -dS $vmlinux_name |") || die "Cannot start objdump";
+
+while (<FILE>) {
+ my $line = $_;
+ chomp($line);
+ if ($state == 0) {
+ if ($line =~ /^([a-f0-9]+)\:/) {
+ if (InRange($1, $target)) {
+ $state = 1;
+ }
+ }
+ } else {
+ if ($line =~ /^([a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9]+)\:/) {
+ my $val = $1;
+ if (!InRange($val, $target)) {
+ last;
+ }
+ if ($val eq $target) {
+ $center = $counter;
+ }
+ }
+ $lines[$counter] = $line;
+
+ $counter = $counter + 1;
+ }
+}
+
+close(FILE);
+
+if ($counter == 0) {
+ print "No matching code found \n";
+ exit;
+}
+
+if ($center == 0) {
+ print "No matching code found \n";
+ exit;
+}
+
+my $start;
+my $finish;
+my $codelines;
+my $binarylines;
+# now we go up and down in the array to find how much we want to print
+
+$start = $center;
+$codelines = 0;
+$binarylines = 0;
+while ($start > 1) {
+ $start = $start - 1;
+ my $line = $lines[$start];
+ if ($line =~ /^([a-f0-9]+)\:/) {
+ $binarylines = $binarylines + 1;
+ } else {
+ $codelines = $codelines + 1;
+ }
+ if ($codelines > 10) {
+ last;
+ }
+ if ($binarylines > 20) {
+ last;
+ }
+}
+
+
+$finish = $center;
+$codelines = 0;
+$binarylines = 0;
+while ($finish < $counter) {
+ $finish = $finish + 1;
+ my $line = $lines[$finish];
+ if ($line =~ /^([a-f0-9]+)\:/) {
+ $binarylines = $binarylines + 1;
+ } else {
+ $codelines = $codelines + 1;
+ }
+ if ($codelines > 10) {
+ last;
+ }
+ if ($binarylines > 20) {
+ last;
+ }
+}
+
+
+my $i;
+
+my $fulltext = "";
+$i = $start;
+while ($i < $finish) {
+ if ($i == $center) {
+ $fulltext = $fulltext . "*$lines[$i] <----- faulting instruction\n";
+ } else {
+ $fulltext = $fulltext . " $lines[$i]\n";
+ }
+ $i = $i +1;
+}
+
+
+
+print $fulltext;
+
--
1.6.0.3
--
Arjan van de Ven Intel Open Source Technology Centre
For development, discussion and tips for power savings,
visit http://www.lesswatts.org
Arjan van de Ven (on Wed, 5 Nov 2008 19:07:26 -0800) wrote:
>I had this script lying around (used on kerneloops.org in a slightly modified form,
>where I use a database as input rather than stdin). I think it's a useful tool,
>at least I find it extremely useful in turning oopses into an "oh duh yes there"
>experience...
>
>Caveats:
>* It only works for oopses not-in-modules
>* It only works nicely for kernels compiled with CONFIG_DEBUG_INFO
>* It's not very fast.
Another caveat: "if ($_ =~ /EIP: 0060:\[\<([a-z0-9]+)\>\]/)" means that
it only works on x86_32.
On Thu, 06 Nov 2008 15:15:22 +1100
Keith Owens <[email protected]> wrote:
> Arjan van de Ven (on Wed, 5 Nov 2008 19:07:26 -0800) wrote:
> >I had this script lying around (used on kerneloops.org in a slightly
> >modified form, where I use a database as input rather than stdin). I
> >think it's a useful tool, at least I find it extremely useful in
> >turning oopses into an "oh duh yes there" experience...
> >
> >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.
>
> Another caveat: "if ($_ =~ /EIP: 0060:\[\<([a-z0-9]+)\>\]/)" means
> that it only works on x86_32.
>
true. I've not tried it/adapted it on any other arch yet.
--
Arjan van de Ven Intel Open Source Technology Centre
For development, discussion and tips for power savings,
visit http://www.lesswatts.org
On Wed, Nov 05, 2008 at 07:07:26PM -0800, Arjan van de Ven wrote:
>Hi,
>
Hi,
thanks for your work!
>
>diff --git a/scripts/markup_oops.pl b/scripts/markup_oops.pl
>new file mode 100644
>index 0000000..c8a2200
>--- /dev/null
>+++ b/scripts/markup_oops.pl
>@@ -0,0 +1,165 @@
>+#!/usr/bin/perl -w
>+
>+# Copyright 2008, Intel Corporation
>+#
>+# This file is part of the Linux kernel
>+#
>+# This program file is free software; you can redistribute it and/or modify it
>+# under the terms of the GNU General Public License as published by the
>+# Free Software Foundation; version 2 of the License.
>+#
>+# Authors:
>+# Arjan van de Ven <[email protected]>
>+
>+
>+my $vmlinux_name = $ARGV[0];
>+
>+#
>+# Step 1: Parse the oops to find the EIP value
>+#
>+
>+my $target = "0";
>+while (<STDIN>) {
>+ if ($_ =~ /EIP: 0060:\[\<([a-z0-9]+)\>\]/) {
>+ $target = $1;
>+ }
>+}
>+
>+if ($target =~ /^f8/) {
>+ print "This script does not work on modules ... \n";
>+ exit;
>+}
>+
>+if ($target eq "0") {
>+ print "No oops found!\n";
>+ print "Usage: \n";
>+ print " dmesg | perl scripts/markup_oops.pl vmlinux\n";
>+ exit;
One thing to note here, no oops doesn't always mean wrong usage. :)
So I think usage should be printed only when the usage is actually
wrong, e.g. ARGV[0] is missed.
>+$start = $center;
>+$codelines = 0;
>+$binarylines = 0;
Why not fold these lines into their definitions?
--
"Sometimes the only way to stay sane is to go a little crazy."