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Subject: Re: [RFC][PATCH 04/10] x86/espfix: use kernel-default PTE mask
To: Andy Lutomirski <luto@kernel.org>
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From: Dave Hansen <dave.hansen@linux.intel.com>
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Date: Thu, 22 Feb 2018 14:05:19 -0800
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On 02/22/2018 01:59 PM, Andy Lutomirski wrote:
>> I think it's good practice to just expose only the *minimal* amount of
>> data necessary.  It's easier to audit and less likely to expose things
>> accidentall.
> But espfix64 is geniunely global.  I'm confused.

I'm the confused one.

In my *first* set of patches to do this, I missed making the espfix64
area global.  This new code apparently got it right, but I assumed the
"new" global area that showed up was a mistake, thus this patch.

I'll change this patch into a commenting patch that calls out the need
for keeping _PAGE_GLOBAL.