From patchwork Thu Apr 30 10:24:42 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Xiao Guangrong X-Patchwork-Id: 6304711 Return-Path: X-Original-To: patchwork-kvm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 622AA9F1C2 for ; Thu, 30 Apr 2015 14:54:14 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 8E398201C0 for ; Thu, 30 Apr 2015 14:54:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B006A201BB for ; Thu, 30 Apr 2015 14:54:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752707AbbD3Oum (ORCPT ); Thu, 30 Apr 2015 10:50:42 -0400 Received: from mga11.intel.com ([192.55.52.93]:39541 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752117AbbD3Ouh (ORCPT ); Thu, 30 Apr 2015 10:50:37 -0400 Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by fmsmga102.fm.intel.com with ESMTP; 30 Apr 2015 07:50:17 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.11,677,1422950400"; d="scan'208";a="718483133" Received: from unknown (HELO xiaohome.ccr.corp.intel.com) ([10.254.208.207]) by fmsmga002.fm.intel.com with ESMTP; 30 Apr 2015 07:50:10 -0700 From: guangrong.xiao@linux.intel.com To: pbonzini@redhat.com Cc: gleb@kernel.org, mtosatti@redhat.com, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, Xiao Guangrong Subject: [PATCH 1/9] KVM: MMU: fix decoding cache type from MTRR Date: Thu, 30 Apr 2015 18:24:42 +0800 Message-Id: <1430389490-24602-12-git-send-email-guangrong.xiao@linux.intel.com> X-Mailer: git-send-email 1.9.3 In-Reply-To: <1430389490-24602-1-git-send-email-guangrong.xiao@linux.intel.com> References: <1430389490-24602-1-git-send-email-guangrong.xiao@linux.intel.com> Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Spam-Status: No, score=-5.3 required=5.0 tests=BAYES_00, DATE_IN_PAST_03_06, RCVD_IN_DNSWL_HI, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Xiao Guangrong There are some bugs in current get_mtrr_type(); 1: bit 2 of mtrr_state->enabled is corresponding bit 11 of IA32_MTRR_DEF_TYPE MSR which completely control MTRR's enablement that means other bits are ignored if it is cleared 2: the fixed MTRR ranges are controlled by bit 1 of mtrr_state->enabled (bit 10 of IA32_MTRR_DEF_TYPE) 3: if MTRR is disabled, UC is applied to all of physical memory rather than mtrr_state->def_type Signed-off-by: Xiao Guangrong --- arch/x86/kvm/mmu.c | 14 ++++++-------- 1 file changed, 6 insertions(+), 8 deletions(-) diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index d43867c..ea3e3e4 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -2393,19 +2393,20 @@ EXPORT_SYMBOL_GPL(kvm_mmu_unprotect_page); static int get_mtrr_type(struct mtrr_state_type *mtrr_state, u64 start, u64 end) { - int i; u64 base, mask; u8 prev_match, curr_match; - int num_var_ranges = KVM_NR_VAR_MTRR; + int i, num_var_ranges = KVM_NR_VAR_MTRR; - if (!mtrr_state->enabled) - return 0xFF; + /* MTRR is completely disabled, use UC for all of physical memory. */ + if (!(mtrr_state->enabled & 0x2)) + return MTRR_TYPE_UNCACHABLE; /* Make end inclusive end, instead of exclusive */ end--; /* Look in fixed ranges. Just return the type as per start */ - if (mtrr_state->have_fixed && (start < 0x100000)) { + if (mtrr_state->have_fixed && (mtrr_state->enabled & 0x1) && + (start < 0x100000)) { int idx; if (start < 0x80000) { @@ -2428,9 +2429,6 @@ static int get_mtrr_type(struct mtrr_state_type *mtrr_state, * Look of multiple ranges matching this address and pick type * as per MTRR precedence */ - if (!(mtrr_state->enabled & 2)) - return mtrr_state->def_type; - prev_match = 0xFF; for (i = 0; i < num_var_ranges; ++i) { unsigned short start_state, end_state;