Re: [PATCH] scripts: improve the decodecode script

From: AmÃrico Wang
Date: Fri Oct 31 2008 - 07:38:53 EST


On Wed, Oct 29, 2008 at 12:20:02PM -0700, Arjan van de Ven wrote:
>On Wed, 29 Oct 2008 17:22:26 +0000
>AmÃrico Wang <xiyou.wangcong@xxxxxxxxx> wrote:
>
>> On Wed, Oct 29, 2008 at 10:00:45AM -0700, Arjan van de Ven wrote:
>> >From 80bf813c2bdc3538d823bb59c2611b40673e395a Mon Sep 17 00:00:00
>> >2001 From: Arjan van de Ven <arjan@xxxxxxxxxxxxxxx>
>> >Date: Wed, 29 Oct 2008 09:57:07 -0700
>> >Subject: [PATCH] scripts: improve the decodecode script
>> >
>> >kerneloops.org has been using an improved "decodecode" script,
>> >specifically it has a special marker that shows which line
>> >in the assembly the oops happened at, like this:
>> >
>> > 20: 83 e0 03 and $0x3,%eax
>> > 23: 09 d8 or %ebx,%eax
>> > 25: 85 db test %ebx,%ebx
>> > 27: 89 02 mov %eax,(%edx)
>> > 29: 74 0f je 0x3a
>> > 2b:* 3b 73 04 cmp 0x4(%ebx),%esi
>> > <-- trapping instruction 2e: 75 05
>> > jne 0x35 30: 89 53 04 mov
>> > %edx,0x4(%ebx) 33: eb 07 jmp 0x3c
>> > 35: 89 53 08 mov %edx,0x8(%ebx)
>> >
>> >this patch updates the kernel copy to also have this functionality.
>> >
>> >Signed-off-by: Arjan van de Ven <arjan@xxxxxxxxxxxxxxx>
>> >---
>> > scripts/decodecode | 32 ++++++++++++++++++++++----------
>> > 1 files changed, 22 insertions(+), 10 deletions(-)
>> >
>> >diff --git a/scripts/decodecode b/scripts/decodecode
>> >index 235d393..dd9bf17 100755
>> >--- a/scripts/decodecode
>> >+++ b/scripts/decodecode
>> >@@ -7,7 +7,7 @@
>> > # AFLAGS=--32 decodecode < 386.oops
>> >
>> > cleanup() {
>> >- rm -f $T $T.s $T.o
>> >+ rm -f $T $T.s $T.o $T.oo $T.aa $T.aaa
>> > exit 1
>> > }
>> >
>> >@@ -44,21 +44,33 @@ if [ $marker -eq 0 ]; then
>> > marker=`expr index "$code" "\("`
>> > fi
>> >
>> >+touch $T.oo
>> > if [ $marker -ne 0 ]; then
>> >- beforemark=`echo "$code" | cut -c-$((${marker} - 1))`
>> >+ echo All code >> $T.oo
>> >+ echo ======== >> $T.oo
>> >+ beforemark=`echo "$code"`
>> > echo -n " .byte 0x" > $T.s
>> >- echo $beforemark | sed -e 's/ /,0x/g' >> $T.s
>> >- as $AFLAGS -o $T.o $T.s
>> >- objdump -S $T.o
>> >- rm $T.o $T.s
>> >+ echo $beforemark | sed -e 's/ /,0x/g' | sed -e 's/<//g' |
>> >sed -e 's/>//g' >> $T.s
>> >+ as $AFLAGS -o $T.o $T.s &> /dev/null
>> >+ objdump -S $T.o | grep -v "/tmp" | grep -v "Disassembly" |
>> >grep -v "\.text" | grep -v "^$" &> $T.ooo
>> >+ cat $T.ooo >> $T.oo
>> >+ rm -f $T.o $T.s $T.ooo
>> >
>> > # and fix code at-and-after marker
>> > code=`echo "$code" | cut -c$((${marker} + 1))-`
>> > fi
>> >-
>> >+echo Code starting with the faulting instruction > $T.aa
>> >+echo =========================================== >> $T.aa
>> > code=`echo $code | sed -e 's/ [<(]/ /;s/[>)] / /;s/ /,0x/g'`
>> > echo -n " .byte 0x" > $T.s
>> > echo $code >> $T.s
>> >-as $AFLAGS -o $T.o $T.s
>> >-objdump -S $T.o
>> >-rm $T $T.s $T.o
>> >+as $AFLAGS -o $T.o $T.s &> /dev/null
>> >+objdump -S $T.o | grep -v "Disassembly" | grep -v "/tmp" | grep -v
>> >"\.text" | grep -v "^$" &> $T.aaa +cat $T.aaa >> $T.aa
>> >+
>> >+faultline=`cat $T.aaa | head -1 | cut -d":" -f2`
>> >+
>> >+cat $T.oo | sed -e "s/\($faultline\)/\*\1 <-- trapping
>> >instruction/g" +echo
>> >+cat $T.aa
>> >+rm -f $T.o $T.s $T $T.oo $T.aa $T.aaa[5~
>>
>> what is $T.aaa[5~ ? :-)
>>
>> And why not call cleanup() here?
>
>good point
>
>update below
>

Looks good, thanks!

If you need, add:

Reviewed-by: WANG Cong <wangcong@xxxxxxxxx>


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