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SubjectRe: [PATCH] x86: Use entire page for the per-cpu GDT only if paravirt-enabled
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Ugh.  Didn't realize that.

On September 29, 2015 11:22:04 AM PDT, Andy Lutomirski <luto@amacapital.net> wrote:
>On Tue, Sep 29, 2015 at 11:18 AM, H. Peter Anvin <hpa@zytor.com> wrote:
>> SGDT would be easy to use, and it is logical that it is faster since
>it reads an internal register. SIDT does too but unlike the GDT has a
>secondary limit (it can never be larger than 4096 bytes) and so all
>limits in the range 4095-65535 are exactly equivalent.
>>
>
>Using the IDT limit would have been a great ideal if Intel hadn't
>decided to clobber it on every VM exit.
>
>--Andy

--
Sent from my Android device with K-9 Mail. Please excuse my brevity.


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