From patchwork Tue Jun 21 03:12:24 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Bandan Das X-Patchwork-Id: 9189207 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 8A00860756 for ; Tue, 21 Jun 2016 03:15:18 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 7BAE227F10 for ; Tue, 21 Jun 2016 03:15:18 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 7090827F89; Tue, 21 Jun 2016 03:15:18 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id B17C227F85 for ; Tue, 21 Jun 2016 03:15:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932557AbcFUDPO (ORCPT ); Mon, 20 Jun 2016 23:15:14 -0400 Received: from mx1.redhat.com ([209.132.183.28]:40620 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753366AbcFUDPL (ORCPT ); Mon, 20 Jun 2016 23:15:11 -0400 Received: from int-mx09.intmail.prod.int.phx2.redhat.com (int-mx09.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 106C1C05B1C8; Tue, 21 Jun 2016 03:13:22 +0000 (UTC) Received: from gigantic.usersys.redhat.com (dhcp-17-169.bos.redhat.com [10.18.17.169]) by int-mx09.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id u5L3DGwp019720; Mon, 20 Jun 2016 23:13:21 -0400 From: Bandan Das To: kvm@vger.kernel.org Cc: pbonzini@redhat.com, guangrong.xiao@linux.intel.com Subject: [RFC PATCH 2/4] mmu: Update ept specific valid bit values Date: Mon, 20 Jun 2016 23:12:24 -0400 Message-Id: <1466478746-14153-3-git-send-email-bsd@redhat.com> In-Reply-To: <1466478746-14153-1-git-send-email-bsd@redhat.com> References: <1466478746-14153-1-git-send-email-bsd@redhat.com> X-Scanned-By: MIMEDefang 2.68 on 10.5.11.22 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.32]); Tue, 21 Jun 2016 03:13:22 +0000 (UTC) Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Until now , is_present_gpte checks for all bits set (XWR) and is_shadow_present_pte() checks for the present bit set. To support execute only mappings we should teach these functions to distinguish 100 as valid based on host support. Signed-off-by: Bandan Das --- arch/x86/kvm/mmu.c | 5 ++++- arch/x86/kvm/paging_tmpl.h | 7 ++++++- 2 files changed, 10 insertions(+), 2 deletions(-) diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index 37b01b1..57d8696 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -308,7 +308,10 @@ static int is_nx(struct kvm_vcpu *vcpu) static int is_shadow_present_pte(u64 pte) { - return pte & PT_PRESENT_MASK && !is_mmio_spte(pte); + int xbit = shadow_xonly_valid ? pte & shadow_x_mask : 0; + + return (pte & PT_PRESENT_MASK) | xbit + && !is_mmio_spte(pte); } static int is_large_pte(u64 pte) diff --git a/arch/x86/kvm/paging_tmpl.h b/arch/x86/kvm/paging_tmpl.h index bc019f7..9f5bd06 100644 --- a/arch/x86/kvm/paging_tmpl.h +++ b/arch/x86/kvm/paging_tmpl.h @@ -133,7 +133,12 @@ static inline int FNAME(is_present_gpte)(unsigned long pte) #if PTTYPE != PTTYPE_EPT return is_present_gpte(pte); #else - return pte & 7; + /* + * For EPT, bits [2:0] can be 001, 100 or 111 + * Further, for 100, logical processor should support + * execute-only. + */ + return (pte & 1) || (shadow_xonly_valid && (pte & 4)); #endif }