barebox.lds.S, why _edata not follows the end of .data section?

[Kevin Du Huanpeng]

Hi, in the linker script,
> _sdata = .;
>. = ALIGN(4);
> .data : { *(.data*) }
? why _edata is not here?
> . = .;
> __barebox_cmd_start = .;
> .barebox_cmd : { KEEP(*(SORT_BY_NAME(.barebox_cmd*))) }
> more....
>  __dynsym_start = .;
> *(.dynsym)
>  __dynsym_end = .;
> }
> _edata = .;
> . = ALIGN(4);
> __bss_start = .;

why _edata is there?
other sections between _sdata and _edata, are they needed to be modified?

duhuanpeng