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From: Paolo Bonzini <pbonzini@redhat.com>
To: "Alexandru Duţu" <alex.dutu@gmail.com>, kvm@vger.kernel.org
Subject: Re: KVM exit on UD interception
Date: Tue, 06 May 2014 18:56:38 +0200	[thread overview]
Message-ID: <53691446.7070706@redhat.com> (raw)
In-Reply-To: <CAEKRH4EYZApPFw6P7xociS7npxzMFgzppv7Ay9k92=ihhf+U-Q@mail.gmail.com>

Il 05/05/2014 17:56, Alexandru Duţu ha scritto:
>
> It seems that re-entering virtualized execution on UD interception
> gives the user the flexibility of running binaries with newer
> instructions on older hardware, if kvm is able to emulate the newer
> instructions. I do not fully understand the details of this scenario,
> is there such a scenario or is it likely that ud_interception() will
> change?

Yes, you are correct.  This emulation capability is used in some cases, 
including: MOVBE, SYSCALL/SYSENTER on 32-bit guests, VMCALL and VMMCALL.

Paolo

  parent reply	other threads:[~2014-05-06 16:56 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-05-05 15:56 KVM exit on UD interception Alexandru Duţu
2014-05-05 17:34 ` Nakajima, Jun
2014-05-05 18:48   ` Alexandru Duţu
2014-05-06  0:07     ` Nakajima, Jun
2014-05-06  0:47       ` Alexandru Duţu
2014-05-06 16:56 ` Paolo Bonzini [this message]
2014-05-06 20:11   ` Alexandru Duţu
2014-05-07  6:55     ` Paolo Bonzini
2014-05-08  3:30       ` Alexandru Duţu

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