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From: Vincent Bernat <vincent@bernat.im>
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Date: Tue, 09 Jan 2018 07:40:26 +0100
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	(Paolo Bonzini's message of "Mon, 8 Jan 2018 17:37:16 -0500 (EST)")
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Subject: Re: [Qemu-devel] [PATCH] target-i386: add pcid to both Sandy Bridge
 and Ivy Bridge
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To: Paolo Bonzini <pbonzini@redhat.com>
Cc: Eduardo Habkost <ehabkost@redhat.com>, Richard Henderson <rth@twiddle.net>, qemu-devel@nongnu.org

 =E2=9D=A6  8 janvier 2018 17:37 -0500, Paolo Bonzini <pbonzini@redhat.com>=
=C2=A0:

>> One possible way to work around this problem is to declare that
>> QEMU 2.12 with KVM will require Linux v3.6 and newer (because we
>> need Linux kernel commit ad756a1603c5 "KVM: VMX: Implement
>> PCID/INVPCID for guests with EPT").
>
> Note that PCID is still not supported for guests without EPT, so
> this would break ept=3D0 with recent "-cpu" models.  I'm not sure of
> a way to fix it; probably it just has to be documented.

>>From the above patch, it seems only INVPCID needs EPT. KVM exposes PCID
whenever it is present on the host.
--=20
When you are about to die, a wombat is better than no company at all.
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