Hi Vikram, On Thu, May 12, 2011 at 9:02 AM, Vikram Narayanan <vikram186@xxxxxxxxx> wrote: > On Thu, May 12, 2011 at 1:51 AM, Mulyadi Santosa > <mulyadi.santosa@xxxxxxxxx> wrote: >> On Thu, May 12, 2011 at 03:11, Vikram Narayanan <vikram186@xxxxxxxxx> 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. > > I think you got it wrong. I will try to put my question more elaborately. > 1) The system is on and BIOS code runs. It gives the control to the > boot loader, say GRUB. > 2) Grub picks up the kernel from the specific partition. (i.e a > vmlinuz image), which denotes that it is compressed. > 3) There are uncompression routines in the kernel itself, If I am not > wrong. So the kernel uncompresses itself. > 4) Now the uncompressed thing is the vmlinux image, right? > 5) The vmlinux is in ELF format. Correct? > 6) If the OS boots and if u try to run an ELF file, the loader knows > how to load that in the RAM. (I mean it knows how to interpret the ELF > format) > 7) Coming back to the vmlinux image, Who takes care of the loading activity.? > 8) Who recognizes that the image is ELF format and do the necessary > things accordingly.? > > Hope I have my question clear now. > If understand your question correctly, you believe that the uncompressed kernel is in elf format. correct?. it is in binary format, so elf interpretation is not required, #5 is wrong. You can see this by building the kernel using 'make V=1' and note the following line in the output, "arch/x86/boot/tools/build arch/x86/boot/setup.bin arch/x86/boot/vmlinux.bin CURRENT > arch/x86/boot/bzImage" means bzImage is made out of two binary files extracted from the elf images. -- Thanks Sudheer _______________________________________________ Kernelnewbies mailing list Kernelnewbies@xxxxxxxxxxxxxxxxx http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
