From 5aea50b5c76b07f2b6bda3426dba998156eaf6d0 Mon Sep 17 00:00:00 2001 From: Arjan van de Ven Date: Tue, 6 Jan 2009 14:40:57 -0800 Subject: 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 /* 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 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 Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- scripts/markup_oops.pl | 162 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 162 insertions(+) create mode 100644 scripts/markup_oops.pl (limited to 'scripts/markup_oops.pl') diff --git a/scripts/markup_oops.pl b/scripts/markup_oops.pl new file mode 100644 index 00000000000..700a7a654a3 --- /dev/null +++ b/scripts/markup_oops.pl @@ -0,0 +1,162 @@ +#!/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 + + +my $vmlinux_name = $ARGV[0]; + +# +# Step 1: Parse the oops to find the EIP value +# + +my $target = "0"; +while () { + if ($_ =~ /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 () { + 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 = 0; +my $binarylines = 0; +# now we go up and down in the array to find how much we want to print + +$start = $center; + +while ($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; + -- cgit v1.2.3-70-g09d2 From d32ad102c6d748b510fd89f1af4232eac1be8732 Mon Sep 17 00:00:00 2001 From: Arjan van de Ven Date: Sun, 11 Jan 2009 15:03:23 +0000 Subject: script: improve markup_oops.pl to also decode oopses in modules There has been some light flamewar on lkml about decoding oopses in modules (as part of the crashdump flamewar). Now this isn't rocket science, just the markup_oops.pl script cheaped out and didn't handle modules. But really; a flamewar all about that?? What happened to C++ in the kernel or reading files from inside the kernel? This patch adds module support to markup_oops.pl; it's not the most pretty perl but it works for my testcases... Signed-off-by: Arjan van de Ven Signed-off-by: Linus Torvalds --- scripts/markup_oops.pl | 59 ++++++++++++++++++++++++++++++++++++++++++-------- 1 file changed, 50 insertions(+), 9 deletions(-) (limited to 'scripts/markup_oops.pl') diff --git a/scripts/markup_oops.pl b/scripts/markup_oops.pl index 700a7a654a3..d40449cafa8 100644 --- a/scripts/markup_oops.pl +++ b/scripts/markup_oops.pl @@ -1,5 +1,7 @@ #!/usr/bin/perl -w +use File::Basename; + # Copyright 2008, Intel Corporation # # This file is part of the Linux kernel @@ -13,23 +15,41 @@ my $vmlinux_name = $ARGV[0]; - +if (!defined($vmlinux_name)) { + my $kerver = `uname -r`; + chomp($kerver); + $vmlinux_name = "/lib/modules/$kerver/build/vmlinux"; + print "No vmlinux specified, assuming $vmlinux_name\n"; +} +my $filename = $vmlinux_name; # # Step 1: Parse the oops to find the EIP value # my $target = "0"; +my $function; +my $module = ""; +my $func_offset; +my $vmaoffset = 0; + while () { - if ($_ =~ /EIP: 0060:\[\<([a-z0-9]+)\>\]/) { + my $line = $_; + if ($line =~ /EIP: 0060:\[\<([a-z0-9]+)\>\]/) { $target = $1; } -} + if ($line =~ /EIP is at ([a-zA-Z0-9\_]+)\+(0x[0-9a-f]+)\/0x[a-f0-9]/) { + $function = $1; + $func_offset = $2; + } -if ($target =~ /^f8/) { - print "This script does not work on modules ... \n"; - exit; + # check if it's a module + if ($line =~ /EIP is at ([a-zA-Z0-9\_]+)\+(0x[0-9a-f]+)\/0x[a-f0-9]+\W\[([a-zA-Z0-9\_\-]+)\]/) { + $module = $3; + } } +my $decodestart = hex($target) - hex($func_offset); +my $decodestop = $decodestart + 8192; if ($target eq "0") { print "No oops found!\n"; print "Usage: \n"; @@ -37,6 +57,29 @@ if ($target eq "0") { exit; } +# if it's a module, we need to find the .ko file and calculate a load offset +if ($module ne "") { + my $dir = dirname($filename); + $dir = $dir . "/"; + my $mod = $module . ".ko"; + my $modulefile = `find $dir -name $mod | head -1`; + chomp($modulefile); + $filename = $modulefile; + if ($filename eq "") { + print "Module .ko file for $module not found. Aborting\n"; + exit; + } + # ok so we found the module, now we need to calculate the vma offset + open(FILE, "objdump -dS $filename |") || die "Cannot start objdump"; + while () { + if ($_ =~ /^([0-9a-f]+) \<$function\>\:/) { + my $fu = $1; + $vmaoffset = hex($target) - hex($fu) - hex($func_offset); + } + } + close(FILE); +} + my $counter = 0; my $state = 0; my $center = 0; @@ -59,9 +102,7 @@ sub InRange { # 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 $vmlinux_name |") || die "Cannot start objdump"; +open(FILE, "objdump -dS --adjust-vma=$vmaoffset --start-address=$decodestart --stop-address=$decodestop $filename |") || die "Cannot start objdump"; while () { my $line = $_; -- cgit v1.2.3-70-g09d2