From mboxrd@z Thu Jan 1 00:00:00 1970 From: Paolo Bonzini Subject: Re: [PATCH V4 7/7] KVM, pkeys: disable PKU feature without ept Date: Sun, 6 Mar 2016 21:32:17 +0100 Message-ID: <56DC93D1.2070204@redhat.com> References: <1457177252-7577-1-git-send-email-huaitong.han@intel.com> <1457177252-7577-8-git-send-email-huaitong.han@intel.com> <56DBF834.1020309@linux.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Cc: kvm@vger.kernel.org To: Xiao Guangrong , Huaitong Han , gleb@kernel.org Return-path: Received: from mail-wm0-f67.google.com ([74.125.82.67]:33929 "EHLO mail-wm0-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750885AbcCFUc0 (ORCPT ); Sun, 6 Mar 2016 15:32:26 -0500 Received: by mail-wm0-f67.google.com with SMTP id p65so7541642wmp.1 for ; Sun, 06 Mar 2016 12:32:26 -0800 (PST) In-Reply-To: <56DBF834.1020309@linux.intel.com> Sender: kvm-owner@vger.kernel.org List-ID: On 06/03/2016 10:28, Xiao Guangrong wrote: >> This patch disables CPUID:PKU without ept, because pkeys is not yet >> implemented for shadow paging. > > Does the PKRU is loaded/saved during vm-enter/vm-exit? Yes, through XSAVE/XRSTOR (which uses eager mode when PKE is active). > BTW, I just very quickly go through the spec, it seems VMX lacks the > ability to intercept the access to PKRU. Right? Indeed RDPKRU/WRPKRU cannot be intercepted. Paolo