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Striking gold in binutils

Striking gold in binutils

Posted Apr 3, 2008 20:31 UTC (Thu) by nix (subscriber, #2304)
In reply to: Striking gold in binutils by stock
Parent article: Striking gold in binutils

IF you would do such a thing, you would understand that on a 64-bit platform we are actually booting a 32bit binary
Actually, the only things that differ between the elf_x86-64 and elf_i386 emulations are details of the GOT and PLT (which don't exist for the kernel normally), details of relocation processing (which isn't carried out for the kernel), and the start address (which the kernel overrides anyway in its custom linker script). So since they do the same thing as far as the kernel's concerned, let's pick the one that everyone's got because it's present even in older x86 binutils and always present in newer ones, and that's elf_i386.

(At least that's my understanding.)

where vmlinux.bin is created by running a custom tool called objcopy :
Not only is objcopy not a 'custom' tool, but part of the GNU binutils, but it predates Linux (although before about 1993 it was called 'copy'). (The renaming was done by, oh look, Ian Lance Taylor. He's been involved in this area for a long, long time. ;} )

(The objcopy run is anyway hardly crucial: like most of the stuff before the final link, it's just a size optimization.)

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