From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755930AbaHVIgW (ORCPT ); Fri, 22 Aug 2014 04:36:22 -0400 Received: from mx1.redhat.com ([209.132.183.28]:57345 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754296AbaHVIgT (ORCPT ); Fri, 22 Aug 2014 04:36:19 -0400 Message-ID: <53F700F7.8020909@redhat.com> Date: Fri, 22 Aug 2014 10:36:07 +0200 From: Paolo Bonzini User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.7.0 MIME-Version: 1.0 To: Wanpeng Li CC: Marcelo Tosatti , Gleb Natapov , Zhang Yang , kvm@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v6 2/2] KVM: nVMX: nested TPR shadow/threshold emulation References: <1408621610-9665-1-git-send-email-wanpeng.li@linux.intel.com> <1408621610-9665-2-git-send-email-wanpeng.li@linux.intel.com> <53F5E720.9000308@redhat.com> <20140821233029.GA2420@kernel> In-Reply-To: <20140821233029.GA2420@kernel> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Il 22/08/2014 01:30, Wanpeng Li ha scritto: > Maybe I misunderstand your comments "On real hardware you could point > the virtual-APIC page to an invalid address." > http://lists.openwall.net/linux-kernel/2014/08/07/344 > That referred to an address that doesn't correspond to RAM. You can use addresses like these in a real processor. But the manual says that "if the “use TPR shadow” VM-execution control is 1, VM entry ensures that the virtual-APIC address is 4-KByte aligned" (24.6.8 Controls For APIC Virtualization). This is the check that is missing. Paolo