From: Paolo Bonzini <pbonzini@redhat.com>
Subject: Re: [PATCH] kvm-unit-tests: VMX: Test suite for preemption timer
Date: Mon, 09 Sep 2013 14:51:06 +0200
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Cc: kvm <kvm@vger.kernel.org>, Jan Kiszka <jan.kiszka@web.de>,
	Gleb Natapov <gleb@redhat.com>
To: Arthur Chunqi Li <yzt356@gmail.com>
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Il 05/09/2013 11:22, Arthur Chunqi Li ha scritto:
> Hi Jan, Gleb and Paolo,
> 
> It suddenly occurred to me that, if guest's PIN_PREEMPT disabled while
> EXI_SAVE_PREEMPT_VALUE enabled, what will happen? The preempt value in
> vmcs will not be affected, yes?

Indeed.  The VMX preemption timer will not count down, so it will remain
set to the same value.  Saving it on exit will actually do nothing.

> This cases fails to test in this patch.

You can add it as a follow up.

Paolo