From cf02bf2407cb217c99cc82f78b7a2e7f0703c9ee Mon Sep 17 00:00:00 2001 From: John-Mark Gurney Date: Wed, 4 Aug 2004 18:03:43 +0000 Subject: [PATCH] add a set of scripts that I posted to -current last year. This makes debugging kernels and kernel modules much easier. It will automaticly locate kernel source, extract kernel module information, and rerun gdb to load kernel module symbol information (if available by compiling module w/ debuging symbols). I have not run these recently, so may need to be updated to work with gdb6. Feel free to fix as appropriate for -current. --- tools/debugscripts/README | 5 ++ tools/debugscripts/kgdb | 65 ++++++++++++++++ tools/debugscripts/kld_deb.py | 143 ++++++++++++++++++++++++++++++++++ 3 files changed, 213 insertions(+) create mode 100644 tools/debugscripts/kgdb create mode 100644 tools/debugscripts/kld_deb.py diff --git a/tools/debugscripts/README b/tools/debugscripts/README index 732d3c2d1a59..bd28cdc547af 100644 --- a/tools/debugscripts/README +++ b/tools/debugscripts/README @@ -14,3 +14,8 @@ perform kernel debugging, you would do: (kgdb) +This directory also contains a kgdb script that given a crash dump number +automaticly extract the path to the kernel source, run gdb to extract +information about kernel modules loaded, and then rerun gdb loading the +necessary symbols for the modules. You need to make sure you build the +modules w/ debugging symbols seperately to get things to work. diff --git a/tools/debugscripts/kgdb b/tools/debugscripts/kgdb new file mode 100644 index 000000000000..2293c5beecb2 --- /dev/null +++ b/tools/debugscripts/kgdb @@ -0,0 +1,65 @@ +#!/bin/sh - +# +# Copyright 2004 John-Mark Gurney +# All rights reserved. +# +# Redistribution and use in source and binary forms, with or without +# modification, are permitted provided that the following conditions +# are met: +# 1. Redistributions of source code must retain the above copyright +# notice, this list of conditions and the following disclaimer. +# 2. Redistributions in binary form must reproduce the above copyright +# notice, this list of conditions and the following disclaimer in the +# documentation and/or other materials provided with the distribution. +# +# THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND +# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE +# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE +# ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE +# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL +# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS +# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) +# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT +# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY +# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF +# SUCH DAMAGE. +# +# $FreeBSD$ + +crashpath="/var/crash" +kld_debpy="kld_deb.py" + +if [ x"$1" = x"-?" -o x"$1" = x"-h" ]; then + echo "Usage: $0 [ [ ] ]" + echo "" + echo "Path for crash dumps: $crashpath" + exit 1 +fi + +if [ x"$1" = x"" ]; then + echo "Need core number." + exit 1 +fi +corenum="$1" +shift + +cmd_file="" +if [ x"$2" != x"" ]; then + cmd_file="-x $2" + shift +fi + +core="$crashpath/vmcore.$corenum" +info="$crashpath/info.$corenum" + +#Get the kernel source compile dir from the info file +kernsrc="`awk 'i == 1 { split($0, a, ":"); print a[2]; i = 0 } $1 == "Versionstring:" { i = 1 }' < "$info"`" + +tmpfile="/tmp/kgdb.asf.$$" +# -mapped (broken?) +# -x command_file +echo "Kernel Source: $kernsrc" +echo "Getting KLD information and locations..." +python $kld_debpy "$kernsrc" "$core" $@ > "$tmpfile" && +gdb $cmd_file -x "$tmpfile" -k -cd "$kernsrc" -s "$kernsrc/kernel.debug" -e "$kernsrc/kernel" -c "$core" +rm "$tmpfile" diff --git a/tools/debugscripts/kld_deb.py b/tools/debugscripts/kld_deb.py new file mode 100644 index 000000000000..3d8e01d70f9d --- /dev/null +++ b/tools/debugscripts/kld_deb.py @@ -0,0 +1,143 @@ +#!/usr/local/bin/python +# +# Copyright 2004 John-Mark Gurney +# All rights reserved. +# +# Redistribution and use in source and binary forms, with or without +# modification, are permitted provided that the following conditions +# are met: +# 1. Redistributions of source code must retain the above copyright +# notice, this list of conditions and the following disclaimer. +# 2. Redistributions in binary form must reproduce the above copyright +# notice, this list of conditions and the following disclaimer in the +# documentation and/or other materials provided with the distribution. +# +# THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND +# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE +# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE +# ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE +# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL +# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS +# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) +# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT +# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY +# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF +# SUCH DAMAGE. +# +# $FreeBSD$ + +import sys +import os +import popen2 +import re + +gdb_cmd = 'gdb -q -k -s %(p)s/kernel.debug -e %(p)s/kernel' +#GDB regex +filenamere = re.compile(r'filename\s+=\s+0x[0-9a-f]+\s("(?P[^"]+)"|(?P<[^>]*>))', re.M) +addressre = re.compile(r'address\s+=\s+(?P0x[0-9a-f]+)', re.M) +nextre = re.compile(r'tqe_next\s+=\s+(?P0x[0-9a-f]+)', re.M) +printre = re.compile(r'\$\d+\s+=\s+') + +#Paths to search for ko's/debugs +kld_debug_paths = [] + +if len(sys.argv[1:]) < 2: + print 'Usage: prog []' + sys.exit(1) + +#Get the base modules path +pfs = sys.argv[1].split('/') +try: + i = 0 + while 1: + i = i + pfs[i:].index('sys') + 1 +except: + pass + +if i == -1: + sys.stderr.write("No sys dir in kernel source path: %s\n" % sys.argv[1]) + sys.exit(0) + +kld_debug_paths.append('/'.join(pfs[:i] + ['modules'])) +kld_debug_paths.append(sys.argv[1]) +#kld_debug_paths.append(sys.argv[3:]) +gdb_cmd = gdb_cmd % {'p': sys.argv[1] } +gdb_cmd += ' -c %s | tee /tmp/gdb.log' % sys.argv[2] + +#Start gdb +gdb = popen2.popen4(gdb_cmd) + +def searchfor(inp, re, j = 0, l = None): + """searchfor(inp, re, j, l): Searches for regex re in inp. It will +automaticly add more lines. If j is set, the lines will be joined together. +l can provide a starting line to help search against. Return value is a +tupple of the last line, and the match if any.""" + ret = None + if not l: + l = inp.readline() + ret = re.search(l) + while l and not ret: + if j: + l += inp.readline() + else: + l = inp.readline() + ret = re.search(l) + + return (l, ret) + +def get_addresses(inp, out): + """get_addresses(inp, out): It will search for addresses from gdb. +inp and out, are the gdb input and output respectively. Return value is +a list of tupples. The tupples contain the filename and the address the +filename was loaded.""" + addr = [] + nxad = 1 + while nxad: + if nxad == 1: + out.write("print linker_files.tqh_first[0]\n") + else: + out.write("print *(struct linker_file *)%d\n" % nxad) + out.flush() + l = searchfor(inp, printre)[0] + l, fn = searchfor(inp, filenamere, 1, l) + if not fn.group('fn'): + sys.stderr.write("got error: %s\n" % fn.group('error')) + nxad = 0 + else: + l, ad = searchfor(inp, addressre, 1, l) + l, nx = searchfor(inp, nextre, 1, l) + addr.append((fn.group('fn'), long(ad.group('ad'), 16))) + nxad = long(nx.group('ad'), 16) + + return addr + +#Get the addresses +addr = get_addresses(gdb[0], gdb[1]) + +#Pass through the resulting addresses, skipping the kernel. +for i in addr[1:]: + for j in kld_debug_paths: + #Try .debug first. + p = popen2.popen4('find %s -type f -name "%s.debug"' % (j, i[0]))[0].read().strip() + if p: + break + #Try just .ko if .debug wasn't found. + p = popen2.popen4('find %s -type f -name "%s"' % (j, i[0]))[0].read().strip() + if p: + break + + if not p: + #Tell our user that we couldn't find it. + a = i[1] + sys.stderr.write("Can't find module: %s (addr: %d + header)\n" % (i[0], a)) + print '#add-symbol-file ', a, '#add header' + continue + + #j = popen2.popen4('objdump --section-headers /boot/kernel/%s | grep "\.text"' % i[0])[0].read().strip().split() + #Output the necessary information + j = popen2.popen4('objdump --section-headers "%s" | grep "\.text"' % p)[0].read().strip().split() + try: + a = int(j[5], 16) + print 'add-symbol-file', p, i[1] + a + except IndexError: + sys.stderr.write('Bad file: %s, address: %d\n' % (i[0], i[1]))