Mapping IIP value to Kernel Symbols

Mapping IIP value to Kernel Symbols

[Karthik Gopalakrishnan]

Hi All.

    I have a value of IIP that I recovered from an MCA. I want to
figure out which instruction in the Kernel resulted in the MCA. Please
let me know how I can find this information. I don't have a 'Kernel
Dump'. I am using the kernel that shipped with RHEL Release 4 Update
2. Since I wanted a relocatable kernel, I gunzip'ed the kernel. The
kernel didn't load at the default address.

    I am not familiar with the Kernel Debugging tools on Linux. I will
be grateful if you can provide suitable pointers.

Thanks & Regards,
Karthik

RE: Mapping IIP value to Kernel Symbols

[Yu, Fenghua]

>    I have a value of IIP that I recovered from an MCA. I want to
>figure out which instruction in the Kernel resulted in the MCA. Please
>let me know how I can find this information. 

You can disassemble kernel to find the instruction for the IIP. The
command is "objdump -d kernel_name". You might also find its system.map
(under /boot) useful.

Thanks.

-Fenghua

Re: Mapping IIP value to Kernel Symbols

[Karthik Gopalakrishnan]

Hi Fenghua.

	Thank You very much. This is exactly what I was looking for. :-)

Regards,
Karthik

Yu, Fenghua wrote:
>>    I have a value of IIP that I recovered from an MCA. I want to
>> figure out which instruction in the Kernel resulted in the MCA. Please
>> let me know how I can find this information. 
> 
> You can disassemble kernel to find the instruction for the IIP. The
> command is "objdump -d kernel_name". You might also find its system.map
> (under /boot) useful.
> 
> Thanks.
> 
> -Fenghua
> 

Re: Mapping IIP value to Kernel Symbols

[Peter Chubb]

>>>>> "Karthik" = Karthik Gopalakrishnan <karthik.g.krishnan@gmail.com> writes:

Karthik> Hi All.  I have a value of IIP that I recovered from an
Karthik> MCA. I want to figure out which instruction in the Kernel
Karthik> resulted in the MCA. 

I find the simplest way is usually to use gdb.

 gdb vmlinux
 gdb> x/i 0xaddress

You can also do
 gdb> list *0xaddress
to find the line iff the kernel was compiled with debugging info and
you have the source available.

--
Dr Peter Chubb  http://www.gelato.unsw.edu.au  peterc AT gelato.unsw.edu.au
http://www.ertos.nicta.com.au           ERTOS within National ICT Australia