[U-Boot] Code relocation in U-boot.

[U-Boot] Code relocation in U-boot.

[Sandeep Sharma]

Hi,

I am analyzing U-Boot code for "relocate_code" function. In this function
after copying the text section and before clearing the bss section we are
doing "fix .rel.dyn relocations". I want to know that what actually we are
doing in this section of code. What does this section actually contains and
what kind of fix we are doing in this. What are relative and absolute fix
that we are doing in this section.

Any kind of help will we highly appreciated.

-- 

Thanks and Regards,
Sandeep Kumar,

[U-Boot] Code relocation in U-boot.

[Albert ARIBAUD]

Le 07/11/2011 14:41, Sandeep Sharma a ?crit :
> Hi,
>
> I am analyzing U-Boot code for "relocate_code" function. In this function
> after copying the text section and before clearing the bss section we are
> doing "fix .rel.dyn relocations". I want to know that what actually we are
> doing in this section of code. What does this section actually contains and
> what kind of fix we are doing in this. What are relative and absolute fix
> that we are doing in this section.
>
> Any kind of help will we highly appreciated.

Hi Sandeep,

I assume you are specifically talking about ARM code in start.S? This 
code is an implementation of the relocation mechanism defined in the ELF 
specifications. Look up 
<http://en.wikipedia.org/wiki/Executable_and_Linkable_Format#References> 
for details.

Amicalement,
-- 
Albert.

[U-Boot] Code relocation in U-boot.

[Sandeep Sharma]

Hi,

You are absolutely right. I am talking about ARM code located in start.S
file.
I am not able to figure out from from the referred link. I also consulted "
http://infocenter.arm.com/help/topic/com.arm.doc.ihi0044d/IHI0044D_aaelf.pdf
"
which talks about arm code relocation but it is also not helpful. It
nowhere talks about ".rel.dyn" section which i referred to in my previous
post. Can You provide any pointer from where i can get understanding of
this section.

Regards,,
Sandeep


On Tue, Nov 8, 2011 at 2:05 AM, Albert ARIBAUD <albert.u.boot@aribaud.net>wrote:

> Le 07/11/2011 14:41, Sandeep Sharma a ?crit :
>
>  Hi,
>>
>> I am analyzing U-Boot code for "relocate_code" function. In this function
>> after copying the text section and before clearing the bss section we are
>> doing "fix .rel.dyn relocations". I want to know that what actually we are
>> doing in this section of code. What does this section actually contains
>> and
>> what kind of fix we are doing in this. What are relative and absolute fix
>> that we are doing in this section.
>>
>> Any kind of help will we highly appreciated.
>>
>
> Hi Sandeep,
>
> I assume you are specifically talking about ARM code in start.S? This code
> is an implementation of the relocation mechanism defined in the ELF
> specifications. Look up <http://en.wikipedia.org/wiki/**
> Executable_and_Linkable_**Format#References<http://en.wikipedia.org/wiki/Executable_and_Linkable_Format#References>>
> for details.
>
> Amicalement,
> --
> Albert.
>



-- 

--
Regards,
Sandeep Kumar,
Mb. - 7350016210