Hi Vaibhav Jain, On Mon, Mar 26, 2012 at 4:01 AM, Vaibhav Jain <vjoss197@gmail.com> wrote:
Thanks a lot for the explanation and the link!! I have just one more question about linker scripts. I am not clear about alignment of sections. Is it necessary to align sections? Can the alignment be different from 4096? In the script that I provided the text and data sections are aligned while the bss section is not. Is there a reason for it ?
The reason for using page alignments is so that the kernel can enforce different access types to the various sections. This is tyically done using the MMU, which would require page alignment. So, for example, the text section would allow executable code, and should be read-only. The .rodata section should not allow executable code and be read-only, and the .data section should not allow executable code, and should allow writes. By having the sections page aligned, it allows the kernel to enforce these using the MMU. -- Dave Hylands Shuswap, BC, Canada http://www.davehylands.com