Home | History | Annotate | Download | only in scripts 
      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 
     10 cleanup() {
     11 	rm -f $T $T.s $T.o $T.oo $T.aa $T.dis
     12 	exit 1
     13 }
     14 
     15 die() {
     16 	echo "$@"
     17 	exit 1
     18 }
     19 
     20 trap cleanup EXIT
     21 
     22 T=`mktemp` || die "cannot create temp file"
     23 code=
     24 cont=
     25 
     26 while read i ; do
     27 
     28 case "$i" in
     29 *Code:*)
     30 	code=$i
     31 	cont=yes
     32 	;;
     33 *)
     34 	[ -n "$cont" ] && {
     35 		xdump="$(echo $i | grep '^[[:xdigit:]<>[:space:]]\+$')"
     36 		if [ -n "$xdump" ]; then
     37 			code="$code $xdump"
     38 		else
     39 			cont=
     40 		fi
     41 	}
     42 	;;
     43 esac
     44 
     45 done
     46 
     47 if [ -z "$code" ]; then
     48 	rm $T
     49 	exit
     50 fi
     51 
     52 echo $code
     53 code=`echo $code | sed -e 's/.*Code: //'`
     54 
     55 width=`expr index "$code" ' '`
     56 width=$((($width-1)/2))
     57 case $width in
     58 1) type=byte ;;
     59 2) type=2byte ;;
     60 4) type=4byte ;;
     61 esac
     62 
     63 disas() {
     64 	${CROSS_COMPILE}as $AFLAGS -o $1.o $1.s > /dev/null 2>&1
     65 
     66 	if [ "$ARCH" = "arm" ]; then
     67 		if [ $width -eq 2 ]; then
     68 			OBJDUMPFLAGS="-M force-thumb"
     69 		fi
     70 
     71 		${CROSS_COMPILE}strip $1.o
     72 	fi
     73 
     74 	if [ "$ARCH" = "arm64" ]; then
     75 		if [ $width -eq 4 ]; then
     76 			type=inst
     77 		fi
     78 
     79 		${CROSS_COMPILE}strip $1.o
     80 	fi
     81 
     82 	${CROSS_COMPILE}objdump $OBJDUMPFLAGS -S $1.o | \
     83 		grep -v "/tmp\|Disassembly\|\.text\|^$" > $1.dis 2>&1
     84 }
     85 
     86 marker=`expr index "$code" "\<"`
     87 if [ $marker -eq 0 ]; then
     88 	marker=`expr index "$code" "\("`
     89 fi
     90 
     91 touch $T.oo
     92 if [ $marker -ne 0 ]; then
     93 	echo All code >> $T.oo
     94 	echo ======== >> $T.oo
     95 	beforemark=`echo "$code"`
     96 	echo -n "	.$type 0x" > $T.s
     97 	echo $beforemark | sed -e 's/ /,0x/g; s/[<>()]//g' >> $T.s
     98 	disas $T
     99 	cat $T.dis >> $T.oo
    100 	rm -f $T.o $T.s $T.dis
    101 
    102 # and fix code at-and-after marker
    103 	code=`echo "$code" | cut -c$((${marker} + 1))-`
    104 fi
    105 echo Code starting with the faulting instruction  > $T.aa
    106 echo =========================================== >> $T.aa
    107 code=`echo $code | sed -e 's/ [<(]/ /;s/[>)] / /;s/ /,0x/g; s/[>)]$//'`
    108 echo -n "	.$type 0x" > $T.s
    109 echo $code >> $T.s
    110 disas $T
    111 cat $T.dis >> $T.aa
    112 
    113 # (lines of whole $T.oo) - (lines of $T.aa, i.e. "Code starting") + 3,
    114 # i.e. the title + the "===..=" line (sed is counting from 1, 0 address is
    115 # special)
    116 faultlinenum=$(( $(wc -l $T.oo  | cut -d" " -f1) - \
    117 		 $(wc -l $T.aa  | cut -d" " -f1) + 3))
    118 
    119 faultline=`cat $T.dis | head -1 | cut -d":" -f2-`
    120 faultline=`echo "$faultline" | sed -e 's/\[/\\\[/g; s/\]/\\\]/g'`
    121 
    122 cat $T.oo | sed -e "${faultlinenum}s/^\(.*:\)\(.*\)/\1\*\2\t\t<-- trapping instruction/"
    123 echo
    124 cat $T.aa
    125 cleanup
    126