lkml.org 
[lkml]   [2007]   [Jun]   [22]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
Subject[PATCH v2] doc/oops-tracing: add Code: decode info
On Fri, 22 Jun 2007 16:26:39 +0200 Andi Kleen wrote:

> On Friday 22 June 2007 07:51:08 Randy Dunlap wrote:
> > From: Randy Dunlap <randy.dunlap@oracle.com>
> >
> > Add info that the Code: bytes line contains <xy> or (wxyz) in some
> > architecture oops reports and what that means.
> >
> > Add URL for a script by Andi Kleen that reads the Code: line from an Oops
> > report file and generates assembly code from the hex bytes.
> > (This script does not handle Code: lines that contain <xy> or (wxyz)
> > markings.)
>
> Should probably fix that and put it into scripts/ then



From: Randy Dunlap <randy.dunlap@oracle.com>

Add info that the Code: bytes line contains <xy> or (wxyz) in some
architecture oops reports and what that means.

Add a script by Andi Kleen that reads the Code: line from an Oops
report file and generates assembly code from the hex bytes.

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
---
Documentation/oops-tracing.txt | 14 ++++++++++++++
scripts/decodecode | 20 ++++++++++++++++++++
2 files changed, 34 insertions(+)

--- linux-2.6.22-rc5.orig/Documentation/oops-tracing.txt
+++ linux-2.6.22-rc5/Documentation/oops-tracing.txt
@@ -86,6 +86,20 @@ stuff are the values reported by the Oop
and do a replace of spaces to "\x" - that's what I do, as I'm too lazy
to write a program to automate this all).

+Alternatively, you can use the shell script in scripts/decodecode.
+Its usage is: decodecode < oops.txt
+
+The hex bytes that follow "Code:" may (in some architectures) have a series
+of bytes that precede the current instruction pointer as well as bytes at and
+following the current instruction pointer. In some cases, one instruction
+byte or word is surrounded by <> or (), as in "<86>" or "(f00d)". These
+<> or () markings indicate the current instruction pointer. Example from
+i386, split into multiple lines for readability:
+
+Code: f9 0f 8d f9 00 00 00 8d 42 0c e8 dd 26 11 c7 a1 60 ea 2b f9 8b 50 08 a1
+64 ea 2b f9 8d 34 82 8b 1e 85 db 74 6d 8b 15 60 ea 2b f9 <8b> 43 04 39 42 54
+7e 04 40 89 42 54 8b 43 04 3b 05 00 f6 52 c0
+
Finally, if you want to see where the code comes from, you can do

cd /usr/src/linux
--- /dev/null
+++ linux-2.6.22-rc5/scripts/decodecode
@@ -0,0 +1,20 @@
+#!/bin/sh
+# Disassemble the Code: line in Linux oopses
+# usage: decodecode < oops.file
+
+T=`mktemp`
+
+while read i ; do
+
+case "$i" in
+*Code:*)
+ echo $i
+ echo -n " .byte 0x" > $T.s
+ echo $i | sed -e 's/.*Code: //;s/ [<(]/ /;s/[>)] / /;s/ /,0x/g' >> $T.s
+ as -o $T.o $T.s
+ objdump -S $T.o
+ rm $T.o $T.s
+ ;;
+esac
+
+done
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
\
 
 \ /
  Last update: 2007-06-22 18:47    [W:0.084 / U:0.364 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site