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Subject: Re: [PATCH 01/23] x86, kaiser: prepare assembly for entry/exit CR3
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To: Brian Gerst <brgerst@gmail.com>
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From: Dave Hansen <dave.hansen@linux.intel.com>
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Date: Tue, 31 Oct 2017 18:08:33 -0700
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On 10/31/2017 05:43 PM, Brian Gerst wrote:
>>
>> +       RESTORE_CR3 save_reg=%r14
>> +
>>         testl   %ebx, %ebx                      /* swapgs needed? */
>>         jnz     nmi_restore
>>  nmi_swapgs:
>> _
> This all needs to be conditional on a config option.  Something with
> this amount of performance impact needs to be 100% optional.

The 07/23 patch does just this.  I should have at least called that out
in the description.