From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753214AbaHSJCj (ORCPT ); Tue, 19 Aug 2014 05:02:39 -0400 Received: from mga11.intel.com ([192.55.52.93]:41343 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751593AbaHSJCg (ORCPT ); Tue, 19 Aug 2014 05:02:36 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.01,893,1400050800"; d="scan'208";a="586802774" From: Wanpeng Li To: Paolo Bonzini Cc: Marcelo Tosatti , Gleb Natapov , Zhang Yang , kvm@vger.kernel.org, linux-kernel@vger.kernel.org, Wanpeng Li Subject: [PATCH v2 3/3] KVM: x86: #GP when attempts to write reserved bits of Variable Range MTRRs Date: Tue, 19 Aug 2014 17:04:40 +0800 Message-Id: <1408439080-57721-3-git-send-email-wanpeng.li@linux.intel.com> X-Mailer: git-send-email 1.7.1 In-Reply-To: <1408439080-57721-1-git-send-email-wanpeng.li@linux.intel.com> References: <1408439080-57721-1-git-send-email-wanpeng.li@linux.intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Section 11.11.2.3 of the SDM mentions "All other bits in the IA32_MTRR_PHYSBASEn and IA32_MTRR_PHYSMASKn registers are reserved; the processor generates a general-protection exception(#GP) if software attempts to write to them". This patch do it in kvm. Signed-off-by: Wanpeng Li --- arch/x86/kvm/x86.c | 18 +++++++++++++++--- 1 file changed, 15 insertions(+), 3 deletions(-) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index fb3ea7a..b85da5f 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -1726,6 +1726,7 @@ static bool valid_mtrr_type(unsigned t) static bool mtrr_valid(struct kvm_vcpu *vcpu, u32 msr, u64 data) { int i; + u64 mask = 0; if (!msr_mtrr_valid(msr)) return false; @@ -1749,10 +1750,21 @@ static bool mtrr_valid(struct kvm_vcpu *vcpu, u32 msr, u64 data) /* variable MTRRs */ WARN_ON(!(msr >= 0x200 && msr < 0x200 + 2 * KVM_NR_VAR_MTRR)); - if ((msr & 1) == 0) + for (i = 63; i > boot_cpu_data.x86_phys_bits; i--) + mask |= (1ULL << i); + if ((msr & 1) == 0) { /* MTRR base */ - return valid_mtrr_type(data & 0xff); - /* MTRR mask */ + if (!valid_mtrr_type(data & 0xff)) + return false; + mask |= 0xf00; + } else + /* MTRR mask */ + mask |= 0x7ff; + if (data & mask) { + kvm_inject_gp(vcpu, 0); + return false; + } + return true; } -- 1.9.1