Re: [PATCH] scripts: improve the decodecode script

[Randy Dunlap <rdunlap@xenotime.net>]

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@linux.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@linux.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