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RE: [Xen-devel] [PATCH][VMX] a small clean to vmx_world_restore

To: "Keir Fraser" <Keir.Fraser@xxxxxxxxxxxx>, <xen-devel@xxxxxxxxxxxxxxxxxxx>
Subject: RE: [Xen-devel] [PATCH][VMX] a small clean to vmx_world_restore
From: "Li, Xin B" <xin.b.li@xxxxxxxxx>
Date: Sat, 13 Oct 2007 18:58:55 +0800
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Thread-topic: [Xen-devel] [PATCH][VMX] a small clean to vmx_world_restore
In the case guest is setting PG, guest cr0 is just the value from
c->cr0, why we need to have 2 if statement there.
And having v->arch.guest_table = pagetable_from_pfn(mfn) in the case of
PG is not set is pointless.
-Xin

>
>The current code is correct in that case, and more generally, 
>and also one
>line shorter than the proposed patch.
>
> -- Keir
>
>On 13/10/07 11:49, "Li, Xin B" <xin.b.li@xxxxxxxxx> wrote:
>
>> If guest exits real mode, in vmx_world_restore, c->cr0 is equal to
>> guest_cr0.
>> -Xin 
>> 
>>> I think it's correct as is and changing it in this way 
>could break it.
>>> Whether a reference is acquired depends on new CR0.PG. Whether
>>> a reference
>>> is dropped depends on old CR0.PG. Which is how the code
>>> currently works.
>>> 
>>> -- Keir
>>> 
>>> On 13/10/07 10:51, "Li, Xin B" <xin.b.li@xxxxxxxxx> wrote:
>>> 
>>>> a small clean to vmx_world_restore.
>>>> Signed-off-by: Xin Li <xin.b.li@xxxxxxxxx>
>>>> _______________________________________________
>>>> Xen-devel mailing list
>>>> Xen-devel@xxxxxxxxxxxxxxxxxxx
>>>> http://lists.xensource.com/xen-devel
>>> 
>

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