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Subject: Re: [patches] [PATCH] [21/22] x86_64: Extend bzImage protocol for
	relocatable bzImage
From: Rusty Russell <rusty@rustcorp.com.au>
To: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>, Jeff Garzik <jeff@garzik.org>,
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       Vivek Goyal <vgoyal@in.ibm.com>, linux-kernel@vger.kernel.org,
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       virtualization <virtualization@lists.linux-foundation.org>
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Date: Mon, 30 Apr 2007 13:03:15 +1000
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On Sun, 2007-04-29 at 09:11 -0600, Eric W. Biederman wrote:
>   Right now I'm a little frustrated that insanity below slipped into
>   head.S right after the 32bit entry point after the review said
>   use the normal linux parameters for parameter passing.
>   
>   > #ifdef CONFIG_PARAVIRT
>   >         movl %cs, %eax
>   >         testl $0x3, %eax
>   >         jnz startup_paravirt
>   > #endif
>   
>   The whole thing should be based on a value in the linux parameter block
>   pointed to by %esi, instead of the insane preserve all registers and
>   attempt to be super compatible with everyone.

Dammit, Eric, you spend a lot of time using words like "insane" where
you mean we didn't do everything all at once.

It's *not* clear that using %esi is sane, but nothing in the current
code prevents that.

I was trying to get Xen to use this entry point rather than their own: I
failed, and only lguest now uses it.

Fortunately, this also means it's trivial to change.
Rusty.