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Re: [Xen-devel] about vmxassist

To: "Keir Fraser" <keir.fraser@xxxxxxxxxxxxx>
Subject: Re: [Xen-devel] about vmxassist
From: yushang <yusunn@xxxxxxxxx>
Date: Sun, 9 Mar 2008 00:55:41 +0800
Cc: xen-devel@xxxxxxxxxxxxxxxxxxx
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Thanks . I see . It seems the real-mode emulator is more advanced than
vmxassist ?

2008/3/9, Keir Fraser <keir.fraser@xxxxxxxxxxxxx>:
> On 8/3/08 07:11, "yushang" <yusunn@xxxxxxxxx> wrote:
>
>  >>> I find the code path
>  >>> will enter the native real mode if do not use vmxassist , not a
>  >>> emulation one .
>  > Sorry but I mean the code path of hvmloader , just at the beginning of
>  > hvmloader, if do not use vmxassist execution will return from main and
>  > enter real-address mode then jmp to bios , so bios will run in
>  > real-address mode , is this true ?
>
>
> Yes, as soon as real mode is entered (CR0 bit 0 is cleared) Xen notices that
>  and runs the guest through the full real-mode emulator until CR0 bit 0 is
>  set again.
>
>
>   -- Keir
>
>
>

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