1#!/bin/sh 2# SPDX-License-Identifier: GPL-2.0 3# Disassemble the Code: line in Linux oopses 4# usage: decodecode < oops.file 5# 6# options: set env. variable AFLAGS=options to pass options to "as"; 7# e.g., to decode an i386 oops on an x86_64 system, use: 8# AFLAGS=--32 decodecode < 386.oops 9# PC=hex - the PC (program counter) the oops points to 10 11cleanup() { 12 rm -f $T $T.s $T.o $T.oo $T.aa $T.dis 13 exit 1 14} 15 16die() { 17 echo "$@" 18 exit 1 19} 20 21trap cleanup EXIT 22 23T=`mktemp` || die "cannot create temp file" 24code= 25cont= 26 27while read i ; do 28 29case "$i" in 30*Code:*) 31 code=$i 32 cont=yes 33 ;; 34*) 35 [ -n "$cont" ] && { 36 xdump="$(echo $i | grep '^[[:xdigit:]<>[:space:]]\+$')" 37 if [ -n "$xdump" ]; then 38 code="$code $xdump" 39 else 40 cont= 41 fi 42 } 43 ;; 44esac 45 46done 47 48if [ -z "$code" ]; then 49 rm $T 50 exit 51fi 52 53echo $code 54code=`echo $code | sed -e 's/.*Code: //'` 55 56width=`expr index "$code" ' '` 57width=$((($width-1)/2)) 58case $width in 591) type=byte ;; 602) type=2byte ;; 614) type=4byte ;; 62esac 63 64if [ -z "$ARCH" ]; then 65 case `uname -m` in 66 aarch64*) ARCH=arm64 ;; 67 arm*) ARCH=arm ;; 68 esac 69fi 70 71# Params: (tmp_file, pc_sub) 72disas() { 73 t=$1 74 pc_sub=$2 75 76 ${CROSS_COMPILE}as $AFLAGS -o $t.o $t.s > /dev/null 2>&1 77 78 if [ "$ARCH" = "arm" ]; then 79 if [ $width -eq 2 ]; then 80 OBJDUMPFLAGS="-M force-thumb" 81 fi 82 83 ${CROSS_COMPILE}strip $t.o 84 fi 85 86 if [ "$ARCH" = "arm64" ]; then 87 if [ $width -eq 4 ]; then 88 type=inst 89 fi 90 91 ${CROSS_COMPILE}strip $t.o 92 fi 93 94 if [ $pc_sub -ne 0 ]; then 95 if [ $PC ]; then 96 adj_vma=$(( $PC - $pc_sub )) 97 OBJDUMPFLAGS="$OBJDUMPFLAGS --adjust-vma=$adj_vma" 98 fi 99 fi 100 101 ${CROSS_COMPILE}objdump $OBJDUMPFLAGS -S $t.o | \ 102 grep -v "/tmp\|Disassembly\|\.text\|^$" > $t.dis 2>&1 103} 104 105marker=`expr index "$code" "\<"` 106if [ $marker -eq 0 ]; then 107 marker=`expr index "$code" "\("` 108fi 109 110 111touch $T.oo 112if [ $marker -ne 0 ]; then 113 # 2 opcode bytes and a single space 114 pc_sub=$(( $marker / 3 )) 115 echo All code >> $T.oo 116 echo ======== >> $T.oo 117 beforemark=`echo "$code"` 118 echo -n " .$type 0x" > $T.s 119 echo $beforemark | sed -e 's/ /,0x/g; s/[<>()]//g' >> $T.s 120 disas $T $pc_sub 121 cat $T.dis >> $T.oo 122 rm -f $T.o $T.s $T.dis 123 124# and fix code at-and-after marker 125 code=`echo "$code" | cut -c$((${marker} + 1))-` 126fi 127echo Code starting with the faulting instruction > $T.aa 128echo =========================================== >> $T.aa 129code=`echo $code | sed -e 's/\r//;s/ [<(]/ /;s/[>)] / /;s/ /,0x/g; s/[>)]$//'` 130echo -n " .$type 0x" > $T.s 131echo $code >> $T.s 132disas $T 0 133cat $T.dis >> $T.aa 134 135# (lines of whole $T.oo) - (lines of $T.aa, i.e. "Code starting") + 3, 136# i.e. the title + the "===..=" line (sed is counting from 1, 0 address is 137# special) 138faultlinenum=$(( $(wc -l $T.oo | cut -d" " -f1) - \ 139 $(wc -l $T.aa | cut -d" " -f1) + 3)) 140 141faultline=`cat $T.dis | head -1 | cut -d":" -f2-` 142faultline=`echo "$faultline" | sed -e 's/\[/\\\[/g; s/\]/\\\]/g'` 143 144cat $T.oo | sed -e "${faultlinenum}s/^\([^:]*:\)\(.*\)/\1\*\2\t\t<-- trapping instruction/" 145echo 146cat $T.aa 147cleanup 148