From mboxrd@z Thu Jan 1 00:00:00 1970 From: Paolo Bonzini Subject: Re: [PATCH 1/5] KVM: vmx: fix ept reserved bits for 1-GByte page Date: Mon, 18 Aug 2014 13:18:37 +0200 Message-ID: <53F1E10D.7060007@redhat.com> References: <1408355431-115633-1-git-send-email-wanpeng.li@linux.intel.com> <53F1DADA.1050603@linux.vnet.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Cc: Gleb Natapov , hpa@zytor.com, x86@kernel.org, kvm@vger.kernel.org, linux-kernel@vger.kernel.org To: Xiao Guangrong , Wanpeng Li Return-path: In-Reply-To: <53F1DADA.1050603@linux.vnet.ibm.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: kvm.vger.kernel.org Il 18/08/2014 12:52, Xiao Guangrong ha scritto: >> > EPT misconfig handler in kvm will check which reason lead to EPT >> > misconfiguration after vmexit. One of the reasons is that an EPT >> > paging-structure entry is configured with settings reserved for >> > future functionality. However, the handler can't identify if >> > paging-structure entry of reserved bits for 1-GByte page are >> > configured, since PDPTE which point to 1-GByte page will reserve >> > bits 29:12 instead of bits 7:3 which are reserved for PDPTE that >> > references an EPT Page Directory. This patch fix it by reserve >> > bits 29:12 for 1-GByte page. > That mask is only set in the lowest pte for 4K page, i think it > is not a problem, no? It will cause KVM to WARN. The EPT memory type will also be ignored for gigabyte pages. Paolo