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Re: [Xen-devel] A useless short jmp?

To: "Li, Xin B" <xin.b.li@xxxxxxxxx>, <xen-devel@xxxxxxxxxxxxxxxxxxx>
Subject: Re: [Xen-devel] A useless short jmp?
From: Keir Fraser <Keir.Fraser@xxxxxxxxxxxx>
Date: Tue, 19 Jun 2007 07:51:19 +0100
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On 19/6/07 03:03, "Li, Xin B" <xin.b.li@xxxxxxxxx> wrote:

>> Hmmm... I'm sure I read somewhere about a jmp to clear the
>> prefetch queue,
> 
> Surely you did read it :-), in the latest Spec (version of May 2007),
> in17.29.3 Enabling and Disabling Paging, it's said a near jump should be
> executed after set or clear PG flag in CR0, but it's a different case
> since we are setting or clearing PE flag, probably plus PG changes too.

But you never need a near jump *and* a long jump, it seems. Makes sense!

 -- Keir



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