Re: [PATCH 3/4] KVM: MMU: notrap it if gpte's reserved is set

From: Avi Kivity
Date: Mon Nov 15 2010 - 04:17:48 EST


On 11/15/2010 07:41 AM, Xiao Guangrong wrote:
On 11/14/2010 06:56 PM, Avi Kivity wrote:
> On 11/12/2010 12:34 PM, Xiao Guangrong wrote:
>> We can past the page fault to guest directly if gpte's reserved
>> is set
>>
>
> How can that work? shadow_notrap_nonpresent_pte causes a fault with
> PFEC.P=PFEC.RSVD=0, while we need PFEC.P=PFEC.RSVD=1.
>

Ah, i missed it for a long time, thanks for you point it out.

The same mistake is in 'prefetch' path, i'll fix it in the v2 version.

Doesn't access.flat catch this?

Ideally we'd have a test case to catch this, but it may be hard to write.

--
error compiling committee.c: too many arguments to function

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