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RE: [Xen-devel] [patch] nx bit shouldn't get set when disabled

To: "Scott Parish" <srparish@xxxxxxxxxx>
Subject: RE: [Xen-devel] [patch] nx bit shouldn't get set when disabled
From: "Nakajima, Jun" <jun.nakajima@xxxxxxxxx>
Date: Wed, 8 Jun 2005 16:29:49 -0700
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Thread-topic: [Xen-devel] [patch] nx bit shouldn't get set when disabled
Scott Parish wrote:
> On Wed, Jun 08, 2005 at 03:47:01PM -0700, Nakajima, Jun wrote:
>> Agree on that part. Should read like:
>>   pte = pte_offset_kernel(pmd, (vstart + (i*PAGE_SIZE)));
>> + pte->pte &= __supported_pte_mask;
>>   pfn = pte->pte >> PAGE_SHIFT;
> I dissent. Same reason as yesterday: the above might work right now,
> but as soon as we enable NX the NX bit will end up in the pfn/mfn.
> sRp

Your are correct. We always need to cut off the NX bit because that's
what HYPERVISOR_dom_mem_op expects. 

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