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Date: Mon, 23 Feb 2004 19:10:17 -0800
From: "H. Peter Anvin" <hpa@zytor.com>
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To: Coywolf Qi Hunt <coywolf@greatcn.org>
CC: Philippe Elie <phil.el@wanadoo.fr>, linux-kernel@vger.kernel.org
Subject: Re: Does Flushing the Queue after PG REALLY a Necessity?
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Coywolf Qi Hunt wrote:
 >
> The problem is there's two jumps in the kernel. Intel's manual only asks 
> for "Execute a near JMP instruction".
> 

A far JMP is definitely sufficient, and serves to normalize EIP as well.

I have uploaded a patch which also preinitializes the GDT, which may 
make the VISWS code a bit less of a special case.

ftp://ftp.kernel.org/pub/linux/kernel/people/hpa/earlymem-4.diff

> If no any reason for the two jumps, the code should be fixed to remains 
> only ONE near jump.

Why are you so obsessed with minimality?  The performance of this code 
matters not one bit.

	-hpa