From patchwork Tue Nov 7 14:56:54 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Isaku Yamahata X-Patchwork-Id: 13449039 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 31D4A38FBE for ; Tue, 7 Nov 2023 15:05:13 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="fzvyf94m" Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.8]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BDE8359F8; Tue, 7 Nov 2023 07:01:55 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1699369317; x=1730905317; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=1RWcx/JOzCLk/pJ/jkdqMRrjny3JQ+XYSvf//pbZ6pg=; b=fzvyf94mYuqXpUIb3yWMuIrKkCVcPSSNNXvlGgzeIN/+uUzZR/wLlcxv HojOBwFz2MP2qJP2hxoRnJeuR4R0Vx6HSVWBoo6WfvalwZ7FWRDZVBtR6 MhLZtRfpfjFRgzVMNZekuw88zGmM1doOaOMJZOWbXg42JCS2Ytcx93u1u eX5HpSfq1NFZPf014zi7umbKit/iri/PgsIs7djKrkOGS764OgzaoxoAD bSBmBhFwuFHdFb0RQ67plIxcUPWlnIfplcs+5lNJYrXxO2CeGJetcriEi Tpd2qKLepzzYxUMrWTUm9we7IL5nU0pEPIToRrfVs7xyC1MNr9vD+hFPz g==; X-IronPort-AV: E=McAfee;i="6600,9927,10887"; a="2462567" X-IronPort-AV: E=Sophos;i="6.03,284,1694761200"; d="scan'208";a="2462567" 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 06:58:25 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.03,284,1694761200"; d="scan'208";a="10851560" 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 06:58:23 -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, Xiaoyao Li , Sean Christopherson Subject: [PATCH v17 088/116] KVM: TDX: Add a place holder for handler of TDX hypercalls (TDG.VP.VMCALL) Date: Tue, 7 Nov 2023 06:56:54 -0800 Message-Id: <3cbe9ff2337cc041edfd63173fbb4fa5da550ef3.1699368322.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 The TDX module specification defines TDG.VP.VMCALL API (TDVMCALL for short) for the guest TD to call hypercall to VMM. When the guest TD issues TDG.VP.VMCALL, the guest TD exits to VMM with a new exit reason of TDVMCALL. The arguments from the guest TD and returned values from the VMM are passed in the guest registers. The guest RCX registers indicates which registers are used. Define helper functions to access those registers as ABI. Define the TDVMCALL exit reason, which is carved out from the VMX exit reason namespace as the TDVMCALL exit from TDX guest to TDX-SEAM is really just a VM-Exit. Add a place holder to handle TDVMCALL exit. Co-developed-by: Xiaoyao Li Signed-off-by: Xiaoyao Li Signed-off-by: Sean Christopherson Signed-off-by: Isaku Yamahata --- arch/x86/include/uapi/asm/vmx.h | 4 ++- arch/x86/kvm/vmx/tdx.c | 53 +++++++++++++++++++++++++++++++++ arch/x86/kvm/vmx/tdx.h | 13 ++++++++ 3 files changed, 69 insertions(+), 1 deletion(-) diff --git a/arch/x86/include/uapi/asm/vmx.h b/arch/x86/include/uapi/asm/vmx.h index b3a30ef3efdd..f0f4a4cf84a7 100644 --- a/arch/x86/include/uapi/asm/vmx.h +++ b/arch/x86/include/uapi/asm/vmx.h @@ -93,6 +93,7 @@ #define EXIT_REASON_TPAUSE 68 #define EXIT_REASON_BUS_LOCK 74 #define EXIT_REASON_NOTIFY 75 +#define EXIT_REASON_TDCALL 77 #define VMX_EXIT_REASONS \ { EXIT_REASON_EXCEPTION_NMI, "EXCEPTION_NMI" }, \ @@ -156,7 +157,8 @@ { EXIT_REASON_UMWAIT, "UMWAIT" }, \ { EXIT_REASON_TPAUSE, "TPAUSE" }, \ { EXIT_REASON_BUS_LOCK, "BUS_LOCK" }, \ - { EXIT_REASON_NOTIFY, "NOTIFY" } + { EXIT_REASON_NOTIFY, "NOTIFY" }, \ + { EXIT_REASON_TDCALL, "TDCALL" } #define VMX_EXIT_REASON_FLAGS \ { VMX_EXIT_REASONS_FAILED_VMENTRY, "FAILED_VMENTRY" } diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c index 317d8cf7f1cd..0128df19fccf 100644 --- a/arch/x86/kvm/vmx/tdx.c +++ b/arch/x86/kvm/vmx/tdx.c @@ -107,6 +107,41 @@ static __always_inline unsigned long tdexit_intr_info(struct kvm_vcpu *vcpu) return kvm_r9_read(vcpu); } +#define BUILD_TDVMCALL_ACCESSORS(param, gpr) \ +static __always_inline \ +unsigned long tdvmcall_##param##_read(struct kvm_vcpu *vcpu) \ +{ \ + return kvm_##gpr##_read(vcpu); \ +} \ +static __always_inline void tdvmcall_##param##_write(struct kvm_vcpu *vcpu, \ + unsigned long val) \ +{ \ + kvm_##gpr##_write(vcpu, val); \ +} +BUILD_TDVMCALL_ACCESSORS(a0, r12); +BUILD_TDVMCALL_ACCESSORS(a1, r13); +BUILD_TDVMCALL_ACCESSORS(a2, r14); +BUILD_TDVMCALL_ACCESSORS(a3, r15); + +static __always_inline unsigned long tdvmcall_exit_type(struct kvm_vcpu *vcpu) +{ + return kvm_r10_read(vcpu); +} +static __always_inline unsigned long tdvmcall_leaf(struct kvm_vcpu *vcpu) +{ + return kvm_r11_read(vcpu); +} +static __always_inline void tdvmcall_set_return_code(struct kvm_vcpu *vcpu, + long val) +{ + kvm_r10_write(vcpu, val); +} +static __always_inline void tdvmcall_set_return_val(struct kvm_vcpu *vcpu, + unsigned long val) +{ + kvm_r11_write(vcpu, val); +} + static inline bool is_td_vcpu_created(struct vcpu_tdx *tdx) { return tdx->tdvpr_pa; @@ -871,6 +906,11 @@ fastpath_t tdx_vcpu_run(struct kvm_vcpu *vcpu) tdx_complete_interrupts(vcpu); + if (tdx->exit_reason.basic == EXIT_REASON_TDCALL) + tdx->tdvmcall.rcx = vcpu->arch.regs[VCPU_REGS_RCX]; + else + tdx->tdvmcall.rcx = 0; + return EXIT_FASTPATH_NONE; } @@ -942,6 +982,17 @@ static int tdx_handle_triple_fault(struct kvm_vcpu *vcpu) return 0; } +static int handle_tdvmcall(struct kvm_vcpu *vcpu) +{ + switch (tdvmcall_leaf(vcpu)) { + default: + break; + } + + tdvmcall_set_return_code(vcpu, TDG_VP_VMCALL_INVALID_OPERAND); + return 1; +} + void tdx_load_mmu_pgd(struct kvm_vcpu *vcpu, hpa_t root_hpa, int pgd_level) { td_vmcs_write64(to_tdx(vcpu), SHARED_EPT_POINTER, root_hpa & PAGE_MASK); @@ -1418,6 +1469,8 @@ int tdx_handle_exit(struct kvm_vcpu *vcpu, fastpath_t fastpath) return tdx_handle_exception(vcpu); case EXIT_REASON_EXTERNAL_INTERRUPT: return tdx_handle_external_interrupt(vcpu); + case EXIT_REASON_TDCALL: + return handle_tdvmcall(vcpu); case EXIT_REASON_EPT_VIOLATION: return tdx_handle_ept_violation(vcpu); case EXIT_REASON_EPT_MISCONFIG: diff --git a/arch/x86/kvm/vmx/tdx.h b/arch/x86/kvm/vmx/tdx.h index b29fcda2892b..870a0d15e073 100644 --- a/arch/x86/kvm/vmx/tdx.h +++ b/arch/x86/kvm/vmx/tdx.h @@ -80,6 +80,19 @@ struct vcpu_tdx { struct list_head cpu_list; + union { + struct { + union { + struct { + u16 gpr_mask; + u16 xmm_mask; + }; + u32 regs_mask; + }; + u32 reserved; + }; + u64 rcx; + } tdvmcall; union tdx_exit_reason exit_reason; bool initialized;