Re: [PATCH 12/12] i386 boot: Add an ELF header to bzImage

Eric W. Biederman wrote:

The entrypoint is going to be a major headache, since the standard kernel is
entered in real mode, whereas an ELF file will typically be entered in protected
mode, quite possibly using the C calling convention to pass the command line as
(argc, argv). God only knows how they're going to deal with an initrd.

It may very well be that the ELF magic number has to be obfuscated.

The entry point that is exported is the kernels protected mode entry point
that is used after the real mode code has been run. This is to allow
bootloaders like kexec where running the real-mode code is insane or
impossible to be used.

The calling conventions though are not changed, this is just formalizing
something that various groups have been doing for years. Since it is
all in the bzImage we still only have a single file format to support,
so any bootloader that can load a standard bzImage and run the kernels
real mode code should still do it that way but. If you can't the
rest of the information is available.


Well, it doesn't help if what you end up with for some bootloader is a nonfunctioning kernel.

-hpa
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