From patchwork Tue Nov 7 14:56:22 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Isaku Yamahata X-Patchwork-Id: 13448985 Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 98280328AC for ; Tue, 7 Nov 2023 15:01:44 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="MdmPbkOT" Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.8]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D64B43AA2; Tue, 7 Nov 2023 06:59:28 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1699369173; x=1730905173; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=V5Z9ts9lz5ErRiy1w58Lri6Y/uQuQk2vZCGzbuyoFqY=; b=MdmPbkOTwPM1PF0gMA1uxUfB40jX2OUJ3wiJEBVaNExj83k3/CeKp/5u NgJF3M9oAlNtHY1K6dMyJTJ9o68KSNKKz9/37NiomaO7yT07DMKBNWo57 2diK4NPuC+a2Pa7/tNXEcHy31ug1qFbAaYfH0NeJ/mcMdKYNmevW+6852 e7WU11C3r9xuH/ews90Exw+sAzsz6Q4GUpukU4WOm5uf1kjz6jo968Foo cw8k5xZrczHVCz2t+6bNMYD+egUpcCDunB2INlQm5wyQ/gG1sYKIEbg2d duq/RlEQM389W1oHhc7j/OOIE4t1gfWMUEUW+quU+Ga0HoL41R5h9gxLR A==; X-IronPort-AV: E=McAfee;i="6600,9927,10887"; a="2462377" X-IronPort-AV: E=Sophos;i="6.03,284,1694761200"; d="scan'208";a="2462377" Received: from fmviesa001.fm.intel.com ([10.60.135.141]) by fmvoesa102.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 07 Nov 2023 06:58:16 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.03,284,1694761200"; d="scan'208";a="10851426" Received: from ls.sc.intel.com (HELO localhost) ([172.25.112.31]) by smtpauth.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 07 Nov 2023 06:58:15 -0800 From: isaku.yamahata@intel.com To: kvm@vger.kernel.org, linux-kernel@vger.kernel.org Cc: isaku.yamahata@intel.com, isaku.yamahata@gmail.com, Paolo Bonzini , erdemaktas@google.com, Sean Christopherson , Sagi Shahar , David Matlack , Kai Huang , Zhi Wang , chen.bo@intel.com, hang.yuan@intel.com, tina.zhang@intel.com Subject: [PATCH v17 056/116] KVM: TDX: MTRR: implement get_mt_mask() for TDX Date: Tue, 7 Nov 2023 06:56:22 -0800 Message-Id: <3a0393389cb0c2b594a94792ba0a704f0c7291bc.1699368322.git.isaku.yamahata@intel.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: References: Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: Isaku Yamahata Because TDX virtualize cpuid[0x1].EDX[MTRR: bit 12] to fixed 1, guest TD thinks MTRR is supported. Although TDX supports only WB for private GPA, it's desirable to support MTRR for shared GPA. As guest access to MTRR MSRs causes #VE and KVM/x86 tracks the values of MTRR MSRs, the remining part is to implement get_mt_mask method for TDX for shared GPA. Pass around shared bit from kvm fault handler to get_mt_mask method so that it can determine if the gfn is shared or private. Implement get_mt_mask() following vmx case for shared GPA and return WB for private GPA. the existing vmx_get_mt_mask() can't be directly used as CPU state(CR0.CD) is protected. GFN passed to kvm_mtrr_check_gfn_range_consistency() should include shared bit. Suggested-by: Kai Huang Signed-off-by: Isaku Yamahata --- arch/x86/kvm/vmx/main.c | 10 +++++++++- arch/x86/kvm/vmx/tdx.c | 23 +++++++++++++++++++++++ arch/x86/kvm/vmx/x86_ops.h | 2 ++ 3 files changed, 34 insertions(+), 1 deletion(-) diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c index d1387e7b2362..bbc6aedf6e0c 100644 --- a/arch/x86/kvm/vmx/main.c +++ b/arch/x86/kvm/vmx/main.c @@ -228,6 +228,14 @@ static void vt_load_mmu_pgd(struct kvm_vcpu *vcpu, hpa_t root_hpa, vmx_load_mmu_pgd(vcpu, root_hpa, pgd_level); } +static u8 vt_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio) +{ + if (is_td_vcpu(vcpu)) + return tdx_get_mt_mask(vcpu, gfn, is_mmio); + + return vmx_get_mt_mask(vcpu, gfn, is_mmio); +} + static int vt_mem_enc_ioctl(struct kvm *kvm, void __user *argp) { if (!is_td(kvm)) @@ -347,7 +355,7 @@ struct kvm_x86_ops vt_x86_ops __initdata = { .set_tss_addr = vmx_set_tss_addr, .set_identity_map_addr = vmx_set_identity_map_addr, - .get_mt_mask = vmx_get_mt_mask, + .get_mt_mask = vt_get_mt_mask, .get_exit_info = vmx_get_exit_info, diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c index 5f2a27f72cf1..27714d07bbff 100644 --- a/arch/x86/kvm/vmx/tdx.c +++ b/arch/x86/kvm/vmx/tdx.c @@ -363,6 +363,29 @@ int tdx_vm_init(struct kvm *kvm) return 0; } +u8 tdx_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio) +{ + if (is_mmio) + return MTRR_TYPE_UNCACHABLE << VMX_EPT_MT_EPTE_SHIFT; + + if (!kvm_arch_has_noncoherent_dma(vcpu->kvm)) + return (MTRR_TYPE_WRBACK << VMX_EPT_MT_EPTE_SHIFT) | VMX_EPT_IPAT_BIT; + + /* + * TDX enforces CR0.CD = 0 and KVM MTRR emulation enforces writeback. + * TODO: implement MTRR MSR emulation so that + * MTRRCap: SMRR=0: SMRR interface unsupported + * WC=0: write combining unsupported + * FIX=0: Fixed range registers unsupported + * VCNT=0: number of variable range regitsers = 0 + * MTRRDefType: E=1, FE=0, type=writeback only. Don't allow other value. + * E=1: enable MTRR + * FE=0: disable fixed range MTRRs + * type: default memory type=writeback + */ + return MTRR_TYPE_WRBACK << VMX_EPT_MT_EPTE_SHIFT; +} + int tdx_vcpu_create(struct kvm_vcpu *vcpu) { struct kvm_tdx *kvm_tdx = to_kvm_tdx(vcpu->kvm); diff --git a/arch/x86/kvm/vmx/x86_ops.h b/arch/x86/kvm/vmx/x86_ops.h index e4cbcf04d7e3..810b8e7c41e2 100644 --- a/arch/x86/kvm/vmx/x86_ops.h +++ b/arch/x86/kvm/vmx/x86_ops.h @@ -150,6 +150,7 @@ int tdx_vm_ioctl(struct kvm *kvm, void __user *argp); int tdx_vcpu_create(struct kvm_vcpu *vcpu); void tdx_vcpu_free(struct kvm_vcpu *vcpu); void tdx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event); +u8 tdx_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio); int tdx_vcpu_ioctl(struct kvm_vcpu *vcpu, void __user *argp); @@ -176,6 +177,7 @@ static inline int tdx_vm_ioctl(struct kvm *kvm, void __user *argp) { return -EOP static inline int tdx_vcpu_create(struct kvm_vcpu *vcpu) { return -EOPNOTSUPP; } static inline void tdx_vcpu_free(struct kvm_vcpu *vcpu) {} static inline void tdx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event) {} +static inline u8 tdx_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio) { return 0; } static inline int tdx_vcpu_ioctl(struct kvm_vcpu *vcpu, void __user *argp) { return -EOPNOTSUPP; }