From mboxrd@z Thu Jan 1 00:00:00 1970 From: Paolo Bonzini Subject: Re: KVM Nested L2 guest startup problems Date: Wed, 07 May 2014 13:37:14 +0200 Message-ID: <536A1AEA.9020309@redhat.com> References: <53636B1D.8030405@redhat.com> <5363BF42.9020505@redhat.com> <5369F5B0.7050307@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Cc: Hu Yaohui , Bandan Das , kvm , "linux-kernel@vger.kernel.org" , Muli Ben-Yehuda To: Abel Gordon Return-path: In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org List-Id: kvm.vger.kernel.org Il 07/05/2014 13:16, Abel Gordon ha scritto: >> > PLE should be left enabled, I think. > Well... the PLE settings L0 uses to run L1 (vmcs01) may be different > than the PLE settings L1 configured to run L2 (vmcs12). > For example, L0 can use a ple_gap to run L1 that is bigger than the > ple_gap L1 configured to run L2. Or L0 can use a ple_window to run L1 > that is smaller than the ple_window L1 configured to run L2. That's correct. We should leave PLE enabled while running L2, but hide the feature altogether from L1. Paolo > So seems PLE should never be exposed to L1 or an appropriate nested > handling needs to be implemented. Note the handling may become complex > because in some cases a PLE exit from L2 should be handled directly by > L0 and not passed to L1... remember nested preemption timer support :) > ?