From patchwork Thu Jul 16 03:16:20 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Yang, Weijiang" X-Patchwork-Id: 11666569 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 8F954722 for ; Thu, 16 Jul 2020 03:17:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 81B3920775 for ; Thu, 16 Jul 2020 03:17:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728236AbgGPDRF (ORCPT ); Wed, 15 Jul 2020 23:17:05 -0400 Received: from mga06.intel.com ([134.134.136.31]:8148 "EHLO mga06.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728230AbgGPDRE (ORCPT ); Wed, 15 Jul 2020 23:17:04 -0400 IronPort-SDR: ChyNNk7yQntGanN2rjJTM8gzJbbPNyz9WCCh8pBdtkdHGYCzRK5OSbLB7KQEg9z/Zpto8/qJNG 5huMYpV4Cc+Q== X-IronPort-AV: E=McAfee;i="6000,8403,9683"; a="210844851" X-IronPort-AV: E=Sophos;i="5.75,357,1589266800"; d="scan'208";a="210844851" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga001.jf.intel.com ([10.7.209.18]) by orsmga104.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 15 Jul 2020 20:17:03 -0700 IronPort-SDR: AtgFEO+Y19gOCmjaM1cJXjz5Bw/OabRMHZWeZ3Hlub8IMKfHzBUipcl1NZG6Uk1sQtjVk0DPsl 9QXbm0nqmpfA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.75,357,1589266800"; d="scan'208";a="360910445" Received: from unknown (HELO local-michael-cet-test.sh.intel.com) ([10.239.159.128]) by orsmga001.jf.intel.com with ESMTP; 15 Jul 2020 20:17:01 -0700 From: Yang Weijiang To: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, pbonzini@redhat.com, sean.j.christopherson@intel.com, jmattson@google.com Cc: yu.c.zhang@linux.intel.com, Yang Weijiang Subject: [RESEND v13 04/11] KVM: VMX: Configure CET settings upon guest CR0/4 changing Date: Thu, 16 Jul 2020 11:16:20 +0800 Message-Id: <20200716031627.11492-5-weijiang.yang@intel.com> X-Mailer: git-send-email 2.17.2 In-Reply-To: <20200716031627.11492-1-weijiang.yang@intel.com> References: <20200716031627.11492-1-weijiang.yang@intel.com> Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org CR4.CET is master control bit for CET function. There're mutual constrains between CR0.WP and CR4.CET, so need to check the dependent bit while changing the control registers. The processor does not allow CR4.CET to be set if CR0.WP = 0,similarly, it does not allow CR0.WP to be cleared while CR4.CET = 1. In either case, KVM would inject #GP to guest. CET state load bit is set/cleared along with CR4.CET bit set/clear. Note: SHSTK and IBT features share one control MSR: MSR_IA32_{U,S}_CET, which means it's difficult to hide one feature from another in the case of SHSTK != IBT, after discussed in community, it's agreed to allow guest control two features independently as it won't introduce security hole. Signed-off-by: Yang Weijiang --- arch/x86/kvm/vmx/capabilities.h | 5 +++++ arch/x86/kvm/vmx/vmx.c | 30 ++++++++++++++++++++++++++++-- arch/x86/kvm/x86.c | 3 +++ 3 files changed, 36 insertions(+), 2 deletions(-) diff --git a/arch/x86/kvm/vmx/capabilities.h b/arch/x86/kvm/vmx/capabilities.h index 4bbd8b448d22..dbc87c5997cc 100644 --- a/arch/x86/kvm/vmx/capabilities.h +++ b/arch/x86/kvm/vmx/capabilities.h @@ -103,6 +103,11 @@ static inline bool cpu_has_load_perf_global_ctrl(void) (vmcs_config.vmexit_ctrl & VM_EXIT_LOAD_IA32_PERF_GLOBAL_CTRL); } +static inline bool cpu_has_load_cet_ctrl(void) +{ + return (vmcs_config.vmentry_ctrl & VM_ENTRY_LOAD_CET_STATE) && + (vmcs_config.vmexit_ctrl & VM_EXIT_LOAD_CET_STATE); +} static inline bool cpu_has_vmx_mpx(void) { return (vmcs_config.vmexit_ctrl & VM_EXIT_CLEAR_BNDCFGS) && diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index a9f135c52cbc..0089943fbb31 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -2510,7 +2510,8 @@ static __init int setup_vmcs_config(struct vmcs_config *vmcs_conf, VM_EXIT_LOAD_IA32_EFER | VM_EXIT_CLEAR_BNDCFGS | VM_EXIT_PT_CONCEAL_PIP | - VM_EXIT_CLEAR_IA32_RTIT_CTL; + VM_EXIT_CLEAR_IA32_RTIT_CTL | + VM_EXIT_LOAD_CET_STATE; if (adjust_vmx_controls(min, opt, MSR_IA32_VMX_EXIT_CTLS, &_vmexit_control) < 0) return -EIO; @@ -2534,7 +2535,8 @@ static __init int setup_vmcs_config(struct vmcs_config *vmcs_conf, VM_ENTRY_LOAD_IA32_EFER | VM_ENTRY_LOAD_BNDCFGS | VM_ENTRY_PT_CONCEAL_PIP | - VM_ENTRY_LOAD_IA32_RTIT_CTL; + VM_ENTRY_LOAD_IA32_RTIT_CTL | + VM_ENTRY_LOAD_CET_STATE; if (adjust_vmx_controls(min, opt, MSR_IA32_VMX_ENTRY_CTLS, &_vmentry_control) < 0) return -EIO; @@ -3133,6 +3135,12 @@ static bool is_cet_state_supported(struct kvm_vcpu *vcpu, u32 xss_states) guest_cpuid_has(vcpu, X86_FEATURE_IBT))); } +static bool is_cet_supported(struct kvm_vcpu *vcpu) +{ + return is_cet_state_supported(vcpu, XFEATURE_MASK_CET_USER | + XFEATURE_MASK_CET_KERNEL); +} + int vmx_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4) { struct vcpu_vmx *vmx = to_vmx(vcpu); @@ -3173,6 +3181,10 @@ int vmx_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4) return 1; } + if ((cr4 & X86_CR4_CET) && (!is_cet_supported(vcpu) || + !(kvm_read_cr0(vcpu) & X86_CR0_WP))) + return 1; + if (vmx->nested.vmxon && !nested_cr4_valid(vcpu, cr4)) return 1; @@ -3204,6 +3216,20 @@ int vmx_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4) hw_cr4 &= ~(X86_CR4_SMEP | X86_CR4_SMAP | X86_CR4_PKE); } + if (cpu_has_load_cet_ctrl()) { + if ((hw_cr4 & X86_CR4_CET) && is_cet_supported(vcpu)) { + vm_entry_controls_setbit(to_vmx(vcpu), + VM_ENTRY_LOAD_CET_STATE); + vm_exit_controls_setbit(to_vmx(vcpu), + VM_EXIT_LOAD_CET_STATE); + } else { + vm_entry_controls_clearbit(to_vmx(vcpu), + VM_ENTRY_LOAD_CET_STATE); + vm_exit_controls_clearbit(to_vmx(vcpu), + VM_EXIT_LOAD_CET_STATE); + } + } + vmcs_writel(CR4_READ_SHADOW, cr4); vmcs_writel(GUEST_CR4, hw_cr4); return 0; diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index ea8a9dc9fbad..906e07039d59 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -815,6 +815,9 @@ int kvm_set_cr0(struct kvm_vcpu *vcpu, unsigned long cr0) if (!(cr0 & X86_CR0_PG) && kvm_read_cr4_bits(vcpu, X86_CR4_PCIDE)) return 1; + if (!(cr0 & X86_CR0_WP) && kvm_read_cr4_bits(vcpu, X86_CR4_CET)) + return 1; + kvm_x86_ops.set_cr0(vcpu, cr0); if ((cr0 ^ old_cr0) & X86_CR0_PG) {