From patchwork Tue Mar 12 23:00:29 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Fenghua Yu X-Patchwork-Id: 10850181 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 5E4E41515 for ; Tue, 12 Mar 2019 23:11:06 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 49AE129617 for ; Tue, 12 Mar 2019 23:11:06 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 47A9329802; Tue, 12 Mar 2019 23:11:06 +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=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, 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 A828629935 for ; Tue, 12 Mar 2019 23:11:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727796AbfCLXK6 (ORCPT ); Tue, 12 Mar 2019 19:10:58 -0400 Received: from mga18.intel.com ([134.134.136.126]:65104 "EHLO mga18.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727188AbfCLXIP (ORCPT ); Tue, 12 Mar 2019 19:08:15 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga006.fm.intel.com ([10.253.24.20]) by orsmga106.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 12 Mar 2019 16:08:14 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.58,472,1544515200"; d="scan'208";a="326744246" Received: from romley-ivt3.sc.intel.com ([172.25.110.60]) by fmsmga006.fm.intel.com with ESMTP; 12 Mar 2019 16:08:14 -0700 From: Fenghua Yu To: "Thomas Gleixner" , "Ingo Molnar" , "H Peter Anvin" , "Dave Hansen" , "Paolo Bonzini" , "Ashok Raj" , "Peter Zijlstra" , "Xiaoyao Li " , "Michael Chan" , "Ravi V Shankar" Cc: "linux-kernel" , "x86" , linux-wireless@vger.kernel.org, netdev@vger.kernel.org, kvm@vger.kernel.org, Xiaoyao Li , Fenghua Yu Subject: [PATCH v5 11/18] kvm/vmx: Emulate MSR TEST_CTL Date: Tue, 12 Mar 2019 16:00:29 -0700 Message-Id: <1552431636-31511-12-git-send-email-fenghua.yu@intel.com> X-Mailer: git-send-email 2.5.0 In-Reply-To: <1552431636-31511-1-git-send-email-fenghua.yu@intel.com> References: <1552431636-31511-1-git-send-email-fenghua.yu@intel.com> Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Xiaoyao Li A control bit (bit 29) in TEST_CTL MSR 0x33 will be introduced in future x86 processors. When bit 29 is set, the processor causes #AC exception for split locked accesses at all CPL. Please check the latest Intel 64 and IA-32 Architectures Software Developer's Manual for more detailed information on the MSR and the split lock bit. This patch emulate MSR TEST_CTL with vmx->msr_test_ctl and does the following: 1. As we emulate MSR TEST_CTL of guest, we should enable the related bits in CORE_CAPABILITY to corretly report this feature to guest. 2. Differentiate MSR TEST_CTL between host and guest. Signed-off-by: Xiaoyao Li Signed-off-by: Fenghua Yu Acked-by: Paolo Bonzini --- arch/x86/kvm/vmx/vmx.c | 35 +++++++++++++++++++++++++++++++++++ arch/x86/kvm/vmx/vmx.h | 1 + arch/x86/kvm/x86.c | 17 ++++++++++++++++- 3 files changed, 52 insertions(+), 1 deletion(-) diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index 30a6bcd735ec..270c6566fd5a 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -1659,6 +1659,12 @@ static int vmx_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info) u32 index; switch (msr_info->index) { + case MSR_TEST_CTL: + if (!msr_info->host_initiated && + !(vcpu->arch.core_capability & CORE_CAP_SPLIT_LOCK_DETECT)) + return 1; + msr_info->data = vmx->msr_test_ctl; + break; #ifdef CONFIG_X86_64 case MSR_FS_BASE: msr_info->data = vmcs_readl(GUEST_FS_BASE); @@ -1799,6 +1805,14 @@ static int vmx_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info) u32 index; switch (msr_index) { + case MSR_TEST_CTL: + if (!(vcpu->arch.core_capability & CORE_CAP_SPLIT_LOCK_DETECT)) + return 1; + + if (data & ~TEST_CTL_ENABLE_SPLIT_LOCK_DETECT) + return 1; + vmx->msr_test_ctl = data; + break; case MSR_EFER: ret = kvm_set_msr_common(vcpu, msr_info); break; @@ -4085,6 +4099,9 @@ static void vmx_vcpu_setup(struct vcpu_vmx *vmx) vmx->arch_capabilities = kvm_get_arch_capabilities(); + /* disable AC split lock by default */ + vmx->msr_test_ctl = 0; + vm_exit_controls_init(vmx, vmx_vmexit_ctrl()); /* 22.2.1, 20.8.1 */ @@ -4122,6 +4139,7 @@ static void vmx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event) vmx->rmode.vm86_active = 0; vmx->spec_ctrl = 0; + vmx->msr_test_ctl = 0; vcpu->arch.microcode_version = 0x100000000ULL; vmx->vcpu.arch.regs[VCPU_REGS_RDX] = get_rdx_init_val(); @@ -6321,6 +6339,21 @@ static void atomic_switch_perf_msrs(struct vcpu_vmx *vmx) msrs[i].host, false); } +static void atomic_switch_msr_test_ctl(struct vcpu_vmx *vmx) +{ + u64 host_msr_test_ctl; + + /* if TEST_CTL MSR doesn't exist on the hardware, we do nothing */ + if (rdmsrl_safe(MSR_TEST_CTL, &host_msr_test_ctl)) + return; + + if (host_msr_test_ctl == vmx->msr_test_ctl) + clear_atomic_switch_msr(vmx, MSR_TEST_CTL); + else + add_atomic_switch_msr(vmx, MSR_TEST_CTL, vmx->msr_test_ctl, + host_msr_test_ctl, false); +} + static void vmx_arm_hv_timer(struct vcpu_vmx *vmx, u32 val) { vmcs_write32(VMX_PREEMPTION_TIMER_VALUE, val); @@ -6562,6 +6595,8 @@ static void vmx_vcpu_run(struct kvm_vcpu *vcpu) atomic_switch_perf_msrs(vmx); + atomic_switch_msr_test_ctl(vmx); + vmx_update_hv_timer(vcpu); /* diff --git a/arch/x86/kvm/vmx/vmx.h b/arch/x86/kvm/vmx/vmx.h index 0ac0a64c7790..8549cba0fb75 100644 --- a/arch/x86/kvm/vmx/vmx.h +++ b/arch/x86/kvm/vmx/vmx.h @@ -191,6 +191,7 @@ struct vcpu_vmx { u64 msr_guest_kernel_gs_base; #endif + u64 msr_test_ctl; u64 arch_capabilities; u64 spec_ctrl; diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index e20cbb8c2b74..ad1df965574e 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -1228,7 +1228,22 @@ EXPORT_SYMBOL_GPL(kvm_get_arch_capabilities); u64 kvm_get_core_capability(void) { - return 0; + u64 data; + + rdmsrl_safe(MSR_IA32_CORE_CAPABILITY, &data); + + /* mask non-virtualizable functions */ + data &= CORE_CAP_SPLIT_LOCK_DETECT; + + /* + * There will be a list of FMS values that have split lock detection + * but lack the CORE CAPABILITY MSR. In this case, we can set + * CORE_CAP_SPLIT_LOCK_DETECT since we emulate MSR CORE_CAPABILITY. + */ + if (boot_cpu_has(X86_FEATURE_SPLIT_LOCK_DETECT)) + data |= CORE_CAP_SPLIT_LOCK_DETECT; + + return data; } EXPORT_SYMBOL_GPL(kvm_get_core_capability);