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Date: Wed, 29 Oct 2008 10:49:20 -0700
From: Randy Dunlap <rdunlap@...otime.net>
To: Arjan van de Ven <arjan@...radead.org>
Cc: akpm@...ux-foundation.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH] scripts: improve the decodecode script
On Wed, 29 Oct 2008 10:00:45 -0700 Arjan van de Ven wrote:
> From 80bf813c2bdc3538d823bb59c2611b40673e395a Mon Sep 17 00:00:00 2001
> From: Arjan van de Ven <arjan@...ux.intel.com>
> 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@...ux.intel.com>
> ---
> 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~
> --
Looks good with the exception of Américo's comments.
Thanks.
---
~Randy
--
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