How vmlinux is recognized?

[mulyadi.santosa@gmail.com (Mulyadi Santosa)]

On Thu, May 12, 2011 at 03:11, Vikram Narayanan <vikram186@gmail.com> wrote:
> Yes. I agree. But how who converts the ELF binary to raw binary so
> that the processor understands. Or how is it actually done?

OK I try my best to understand your question :)

i think I got it...you probably guessed that vmlinux created first,
then vmlinuz... AFAIK, it's the other way around...or more precisely,
not both.

After final phase of final kernel image creation, it will go into
making bootable image first. in order to do that, first it will be
compressed 1st. These days, gz is the choice.

So, it is gzipped..and the boot loading code is appended in front of
it... there, you get vmlinuz.

And vmlinux? developers usually use vmlinux as symbol file... and the
way it is created, back to the above phase, is by linking it according
to the accompanying elf linker script. Finally, ELF that contains
kernel is there.

Another guess, maybe you wanna know how to extract the kernel code
from ELF image? then why so? that is indeed the kernel image
itself...it is just appended ELF headers, sections and so on just to
represent ELF construction. But it is not behaving like standart ELF
binary i.e the entry point is not main() but IIRC start_kernel or
something like that.

that helps you?
-- 
regards,

Mulyadi Santosa
Freelance Linux trainer and consultant

blog: the-hydra.blogspot.com
training: mulyaditraining.blogspot.com