From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755557Ab0DQJIR (ORCPT ); Sat, 17 Apr 2010 05:08:17 -0400 Received: from cn.fujitsu.com ([222.73.24.84]:65224 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1755253Ab0DQJIP (ORCPT ); Sat, 17 Apr 2010 05:08:15 -0400 Message-ID: <4BC97A7D.4070502@cn.fujitsu.com> Date: Sat, 17 Apr 2010 17:08:13 +0800 From: Lai Jiangshan User-Agent: Thunderbird 2.0.0.6 (Windows/20070728) MIME-Version: 1.0 To: Avi Kivity , Marcelo Tosatti , LKML , kvm@vger.kernel.org Subject: [PATCH] kvm: reduce couple for ACC_EXEC_MASK Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The statement "access &= ~(gpte >> PT64_NX_SHIFT);" tries to clear bit ACC_EXEC_MASK actually. This statement relies PT64_NX_SHIFT==63&&ACC_EXEC_MASK=1 This patch reduces this couple. Signed-off-by: Lai Jiangshan --- diff --git a/arch/x86/kvm/paging_tmpl.h b/arch/x86/kvm/paging_tmpl.h index 81eab9a..34f4aa2 100644 --- a/arch/x86/kvm/paging_tmpl.h +++ b/arch/x86/kvm/paging_tmpl.h @@ -101,11 +101,9 @@ static unsigned FNAME(gpte_access)(struct kvm_vcpu *vcpu, pt_element_t gpte) { unsigned access; - access = (gpte & (PT_WRITABLE_MASK | PT_USER_MASK)) | ACC_EXEC_MASK; -#if PTTYPE == 64 - if (is_nx(vcpu)) - access &= ~(gpte >> PT64_NX_SHIFT); -#endif + access = (gpte & (PT_WRITABLE_MASK | PT_USER_MASK)); + if (PTTYPE != 64 || !is_nx(vcpu) || (gpte & PT64_NX_MASK)) + access |= ACC_EXEC_MASK; return access; }