[PATCH] scripts: add ARM support to decodecode

[PATCH] scripts: add ARM support to decodecode

[Rabin Vincent]

This patch adds support for decoding ARM oopses to scripts/decodecode.
The following things are handled:

 - ARCH and CROSS_COMPILE environment variables are respected.

 - The Code: in x86 oopses is in bytes, while it is in either words (4
   bytes) or halfwords for ARM.

 - Some versions of ARM objdump refuse to disassemble instructions
   generated by literal constants (".word 0x...").  The workaround is to
   strip the object file first.

 - The faulting instruction is marked (liked so) in ARM, but <like so>
   in x86.

 - ARM mnemonics may include characters such as [] which need to be
   escaped before being passed to sed for the "<- trapping instruction"
   substitution.

Signed-off-by: Rabin Vincent <rabin@rab.in>
---
I didn't think it was necessary to split this up into separate patches, let me
know if you would prefer that.

 scripts/decodecode |   47 +++++++++++++++++++++++++++++++++++------------
 1 files changed, 35 insertions(+), 12 deletions(-)

diff --git a/scripts/decodecode b/scripts/decodecode
index 4b00647..4d025c9 100755
--- a/scripts/decodecode
+++ b/scripts/decodecode
@@ -7,7 +7,7 @@
 # AFLAGS=--32 decodecode < 386.oops
 
 cleanup() {
-	rm -f $T $T.s $T.o $T.oo $T.aa  $T.aaa
+	rm -f $T $T.s $T.o $T.oo $T.aa $T.dis
 	exit 1
 }
 
@@ -39,6 +39,29 @@ fi
 echo $code
 code=`echo $code | sed -e 's/.*Code: //'`
 
+width=`expr index "$code" ' '`
+width=$[($width-1)/2]
+case $width in
+1) type=byte ;;
+2) type=2byte ;;
+4) type=4byte ;;
+esac
+
+disas() {
+	${CROSS_COMPILE}as $AFLAGS -o $1.o $1.s &> /dev/null
+
+	if [ "$ARCH" == "arm" ]; then
+		if [ $width == 2 ]; then
+			OBJDUMPFLAGS="-M force-thumb"
+		fi
+
+		${CROSS_COMPILE}strip $1.o
+	fi
+
+	${CROSS_COMPILE}objdump $OBJDUMPFLAGS -S $1.o | grep -v "/tmp" | \
+		grep -v "Disassembly" | grep -v "\.text" | grep -v "^$" &> $1.dis
+}
+
 marker=`expr index "$code" "\<"`
 if [ $marker -eq 0 ]; then
 	marker=`expr index "$code" "\("`
@@ -49,12 +72,11 @@ if [ $marker -ne 0 ]; then
 	echo All code >> $T.oo
 	echo ======== >> $T.oo
 	beforemark=`echo "$code"`
-	echo -n "	.byte 0x" > $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  $T.ooo
+	echo -n "	.$type 0x" > $T.s
+	echo $beforemark | sed -e 's/ /,0x/g' | sed -e "s/[<(]//g" | sed -e "s/[>)]//g" >> $T.s
+	disas $T
+	cat $T.dis >> $T.oo
+	rm -f $T.o $T.s $T.dis
 
 # and fix code at-and-after marker
 	code=`echo "$code" | cut -c$((${marker} + 1))-`
@@ -62,13 +84,14 @@ 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
+code=`echo $code | sed -e 's/[>)]$//'`
+echo -n "	.$type 0x" > $T.s
 echo $code >> $T.s
-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
+disas $T
+cat $T.dis >> $T.aa
 
-faultline=`cat $T.aaa | head -1 | cut -d":" -f2`
+faultline=`cat $T.dis | head -1 | cut -d":" -f2`
+faultline=`echo "$faultline" | sed -e 's/\[/\\\[/' | sed -e 's/\]/\\\]/'`
 
 cat $T.oo | sed -e "s/\($faultline\)/\*\1     <-- trapping instruction/g"
 echo
-- 
1.6.5

Re: [PATCH] scripts: add ARM support to decodecode

[Simon Horman]

On Wed, Dec 30, 2009 at 08:23:59PM +0530, Rabin Vincent wrote:
> This patch adds support for decoding ARM oopses to scripts/decodecode.
> The following things are handled:
> 
>  - ARCH and CROSS_COMPILE environment variables are respected.
> 
>  - The Code: in x86 oopses is in bytes, while it is in either words (4
>    bytes) or halfwords for ARM.
> 
>  - Some versions of ARM objdump refuse to disassemble instructions
>    generated by literal constants (".word 0x...").  The workaround is to
>    strip the object file first.
> 
>  - The faulting instruction is marked (liked so) in ARM, but <like so>
>    in x86.
> 
>  - ARM mnemonics may include characters such as [] which need to be
>    escaped before being passed to sed for the "<- trapping instruction"
>    substitution.
> 
> Signed-off-by: Rabin Vincent <rabin@rab.in>
> ---
> I didn't think it was necessary to split this up into separate patches, let me
> know if you would prefer that.
> 
>  scripts/decodecode |   47 +++++++++++++++++++++++++++++++++++------------
>  1 files changed, 35 insertions(+), 12 deletions(-)
> 
> diff --git a/scripts/decodecode b/scripts/decodecode
> index 4b00647..4d025c9 100755
> --- a/scripts/decodecode
> +++ b/scripts/decodecode
> @@ -7,7 +7,7 @@
>  # AFLAGS=--32 decodecode < 386.oops
>  
>  cleanup() {
> -	rm -f $T $T.s $T.o $T.oo $T.aa  $T.aaa
> +	rm -f $T $T.s $T.o $T.oo $T.aa $T.dis
>  	exit 1
>  }
>  
> @@ -39,6 +39,29 @@ fi
>  echo $code
>  code=`echo $code | sed -e 's/.*Code: //'`
>  
> +width=`expr index "$code" ' '`
> +width=$[($width-1)/2]
> +case $width in
> +1) type=byte ;;
> +2) type=2byte ;;
> +4) type=4byte ;;
> +esac
> +
> +disas() {
> +	${CROSS_COMPILE}as $AFLAGS -o $1.o $1.s &> /dev/null
> +
> +	if [ "$ARCH" == "arm" ]; then
> +		if [ $width == 2 ]; then
> +			OBJDUMPFLAGS="-M force-thumb"
> +		fi
> +
> +		${CROSS_COMPILE}strip $1.o
> +	fi
> +
> +	${CROSS_COMPILE}objdump $OBJDUMPFLAGS -S $1.o | grep -v "/tmp" | \
> +		grep -v "Disassembly" | grep -v "\.text" | grep -v "^$" &> $1.dis
> +}
> +
>  marker=`expr index "$code" "\<"`
>  if [ $marker -eq 0 ]; then
>  	marker=`expr index "$code" "\("`
> @@ -49,12 +72,11 @@ if [ $marker -ne 0 ]; then
>  	echo All code >> $T.oo
>  	echo ======== >> $T.oo
>  	beforemark=`echo "$code"`
> -	echo -n "	.byte 0x" > $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  $T.ooo
> +	echo -n "	.$type 0x" > $T.s
> +	echo $beforemark | sed -e 's/ /,0x/g' | sed -e "s/[<(]//g" | sed -e "s/[>)]//g" >> $T.s

It should be possible to combine all these sed invocations into one
(untested):

	echo $beforemark | sed -e 's/ /,0x/g; s/[<(]//g; s/[>)]//g' >> $T.s

	or perhaps even

	echo $beforemark | sed -e 's/ /,0x/g; s/[<>()]//g' >> $T.s

> +	disas $T
> +	cat $T.dis >> $T.oo
> +	rm -f $T.o $T.s $T.dis
>  
>  # and fix code at-and-after marker
>  	code=`echo "$code" | cut -c$((${marker} + 1))-`
> @@ -62,13 +84,14 @@ 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
> +code=`echo $code | sed -e 's/[>)]$//'`
> +echo -n "	.$type 0x" > $T.s
>  echo $code >> $T.s
> -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
> +disas $T
> +cat $T.dis >> $T.aa
>  
> -faultline=`cat $T.aaa | head -1 | cut -d":" -f2`
> +faultline=`cat $T.dis | head -1 | cut -d":" -f2`
> +faultline=`echo "$faultline" | sed -e 's/\[/\\\[/' | sed -e 's/\]/\\\]/'`
>  
>  cat $T.oo | sed -e "s/\($faultline\)/\*\1     <-- trapping instruction/g"
>  echo
> -- 
> 1.6.5
> 
> --
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Re: [PATCH] scripts: add ARM support to decodecode

[Russell King - ARM Linux]

On Wed, Dec 30, 2009 at 08:23:59PM +0530, Rabin Vincent wrote:
> This patch adds support for decoding ARM oopses to scripts/decodecode.
> The following things are handled:
> 
>  - ARCH and CROSS_COMPILE environment variables are respected.
> 
>  - The Code: in x86 oopses is in bytes, while it is in either words (4
>    bytes) or halfwords for ARM.
> 
>  - Some versions of ARM objdump refuse to disassemble instructions
>    generated by literal constants (".word 0x...").  The workaround is to
>    strip the object file first.
> 
>  - The faulting instruction is marked (liked so) in ARM, but <like so>
>    in x86.

I've been debating about changing that so we use () instead of <> to
make things more consistent, but I've been holding off in case there's
still any ksymoops users out there.  Opinions?

[PATCH v2] scripts: add ARM support to decodecode

[Rabin Vincent]

This patch adds support for decoding ARM oopses to scripts/decodecode.
The following things are handled:

 - ARCH and CROSS_COMPILE environment variables are respected.

 - The Code: in x86 oopses is in bytes, while it is in either words (4
   bytes) or halfwords for ARM.

 - Some versions of ARM objdump refuse to disassemble instructions
   generated by literal constants (".word 0x...").  The workaround is to
   strip the object file first.

 - The faulting instruction is marked (liked so) in ARM, but <like so>
   in x86.

 - ARM mnemonics may include characters such as [] which need to be
   escaped before being passed to sed for the "<- trapping instruction"
   substitution.

Signed-off-by: Rabin Vincent <rabin@rab.in>
---
v2: condensed some sed and grep expressions

 scripts/decodecode |   48 +++++++++++++++++++++++++++++++++++-------------
 1 files changed, 35 insertions(+), 13 deletions(-)

diff --git a/scripts/decodecode b/scripts/decodecode
index 4b00647..8b30cc3 100755
--- a/scripts/decodecode
+++ b/scripts/decodecode
@@ -7,7 +7,7 @@
 # AFLAGS=--32 decodecode < 386.oops
 
 cleanup() {
-	rm -f $T $T.s $T.o $T.oo $T.aa  $T.aaa
+	rm -f $T $T.s $T.o $T.oo $T.aa $T.dis
 	exit 1
 }
 
@@ -39,6 +39,29 @@ fi
 echo $code
 code=`echo $code | sed -e 's/.*Code: //'`
 
+width=`expr index "$code" ' '`
+width=$[($width-1)/2]
+case $width in
+1) type=byte ;;
+2) type=2byte ;;
+4) type=4byte ;;
+esac
+
+disas() {
+	${CROSS_COMPILE}as $AFLAGS -o $1.o $1.s &> /dev/null
+
+	if [ "$ARCH" == "arm" ]; then
+		if [ $width == 2 ]; then
+			OBJDUMPFLAGS="-M force-thumb"
+		fi
+
+		${CROSS_COMPILE}strip $1.o
+	fi
+
+	${CROSS_COMPILE}objdump $OBJDUMPFLAGS -S $1.o | \
+		grep -v "/tmp\|Disassembly\|\.text\|^$" &> $1.dis
+}
+
 marker=`expr index "$code" "\<"`
 if [ $marker -eq 0 ]; then
 	marker=`expr index "$code" "\("`
@@ -49,26 +72,25 @@ if [ $marker -ne 0 ]; then
 	echo All code >> $T.oo
 	echo ======== >> $T.oo
 	beforemark=`echo "$code"`
-	echo -n "	.byte 0x" > $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  $T.ooo
+	echo -n "	.$type 0x" > $T.s
+	echo $beforemark | sed -e 's/ /,0x/g; s/[<>()]//g' >> $T.s
+	disas $T
+	cat $T.dis >> $T.oo
+	rm -f $T.o $T.s $T.dis
 
 # 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
+code=`echo $code | sed -e 's/ [<(]/ /;s/[>)] / /;s/ /,0x/g; s/[>)]$//'`
+echo -n "	.$type 0x" > $T.s
 echo $code >> $T.s
-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
+disas $T
+cat $T.dis >> $T.aa
 
-faultline=`cat $T.aaa | head -1 | cut -d":" -f2`
+faultline=`cat $T.dis | head -1 | cut -d":" -f2`
+faultline=`echo "$faultline" | sed -e 's/\[/\\\[/g; s/\]/\\\]/g'`
 
 cat $T.oo | sed -e "s/\($faultline\)/\*\1     <-- trapping instruction/g"
 echo
-- 
1.6.5

Re: [PATCH v2] scripts: add ARM support to decodecode

[Arjan van de Ven]

On Tue, 5 Jan 2010 20:27:58 +0530
Rabin Vincent <rabin@rab.in> wrote:

> This patch adds support for decoding ARM oopses to scripts/decodecode.
> The following things are handled:
> 
>  - ARCH and CROSS_COMPILE environment variables are respected.
> 
>  - The Code: in x86 oopses is in bytes, while it is in either words (4
>    bytes) or halfwords for ARM.
> 
>  - Some versions of ARM objdump refuse to disassemble instructions
>    generated by literal constants (".word 0x...").  The workaround is
> to strip the object file first.
> 
>  - The faulting instruction is marked (liked so) in ARM, but <like so>
>    in x86.
> 
>  - ARM mnemonics may include characters such as [] which need to be
>    escaped before being passed to sed for the "<- trapping
> instruction" substitution.


I'm fine with this, but I wonder if ARM could switch to the <>
convention for the faulting instruction, just to keep things
consistent..

-- 
Arjan van de Ven 	Intel Open Source Technology Centre
For development, discussion and tips for power savings, 
visit http://www.lesswatts.org

Re: [PATCH v2] scripts: add ARM support to decodecode

[Michal Marek]

On 5.1.2010 16:06, Arjan van de Ven wrote:
> On Tue, 5 Jan 2010 20:27:58 +0530
> Rabin Vincent <rabin@rab.in> wrote:
> 
>> This patch adds support for decoding ARM oopses to scripts/decodecode.
>> The following things are handled:
>>
>>  - ARCH and CROSS_COMPILE environment variables are respected.
>>
>>  - The Code: in x86 oopses is in bytes, while it is in either words (4
>>    bytes) or halfwords for ARM.
>>
>>  - Some versions of ARM objdump refuse to disassemble instructions
>>    generated by literal constants (".word 0x...").  The workaround is
>> to strip the object file first.
>>
>>  - The faulting instruction is marked (liked so) in ARM, but <like so>
>>    in x86.
>>
>>  - ARM mnemonics may include characters such as [] which need to be
>>    escaped before being passed to sed for the "<- trapping
>> instruction" substitution.
> 
> 
> I'm fine with this,

Was this an Acked-by? :)


> but I wonder if ARM could switch to the <>
> convention for the faulting instruction, just to keep things
> consistent..

I added the patch to the kbuild tree. () won't appear in the x86 Code:
line, so there should be no problem.

Michal

Re: [PATCH v2] scripts: add ARM support to decodecode

[Russell King - ARM Linux]

On Tue, Jan 05, 2010 at 07:06:58AM -0800, Arjan van de Ven wrote:
> I'm fine with this, but I wonder if ARM could switch to the <>
> convention for the faulting instruction, just to keep things
> consistent..

I did mention exactly that on the previous review round on this patch;
the problem is that it won't change older kernels, and if anyone is
still using ksymoops or similar parsing stuff, it could break on
such a change.

Re: [PATCH v2] scripts: add ARM support to decodecode

[Daniel Jacobowitz]

On Tue, Jan 05, 2010 at 08:27:58PM +0530, Rabin Vincent wrote:
>  - Some versions of ARM objdump refuse to disassemble instructions
>    generated by literal constants (".word 0x...").  The workaround is to
>    strip the object file first.

FYI, more recent binutils support .iword for this purpose.  That
probably doesn't help you in decodecode though.

-- 
Daniel Jacobowitz
CodeSourcery

Re: [PATCH v2] scripts: add ARM support to decodecode

[Simon Horman]

On Tue, Jan 05, 2010 at 08:27:58PM +0530, Rabin Vincent wrote:
> This patch adds support for decoding ARM oopses to scripts/decodecode.
> The following things are handled:
> 
>  - ARCH and CROSS_COMPILE environment variables are respected.
> 
>  - The Code: in x86 oopses is in bytes, while it is in either words (4
>    bytes) or halfwords for ARM.
> 
>  - Some versions of ARM objdump refuse to disassemble instructions
>    generated by literal constants (".word 0x...").  The workaround is to
>    strip the object file first.
> 
>  - The faulting instruction is marked (liked so) in ARM, but <like so>
>    in x86.
> 
>  - ARM mnemonics may include characters such as [] which need to be
>    escaped before being passed to sed for the "<- trapping instruction"
>    substitution.
> 
> Signed-off-by: Rabin Vincent <rabin@rab.in>
> ---
> v2: condensed some sed and grep expressions

Condensation portion Acked-by: Simon Horman <horms@verge.net.au>