From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Carl Holtje ;021;vcsg6;" <cwh0803@cs.rit.edu>
Subject: Re: [Q] GRUB -> __start_xen?
Date: Fri, 24 Jun 2005 14:54:18 -0400 (EDT)
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To: Bharadwaj Yadavalli <bharadwaj.yadavalli@hp.com>
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On Fri, 24 Jun 2005, Bharadwaj Yadavalli wrote:

> I am trying to understand the internals of Xen.
>
> On x86 (and may be other architectures), it appears to me
> that xen's entry point is
>
>          void __init __start_xen(multiboot_info_t *mbi)
>
> that lives in xeno-unstable.bk/xen/arch/x86/setup.c.
>
> 1. Who builds the structure mbi and calls __start_xen?

See xen/arch/x86/boot/x86_32.S .. __start_xen is called from there, with
the multiboot info..

It is at this point that assembler becomes C code, and everything is
easier to debug. :)

> 2. How is __satrt_xen registered as the entry point?

__start_xen is not the "real" entry point; instead it's the ENTRY(start)
line in xen/arch/x86/boot/x86_32.S

Carl

- --

"There are 10 types of people in the world: Those who understand binary
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