From patchwork Tue Nov 7 14:56:53 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Isaku Yamahata X-Patchwork-Id: 13449021 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 8EEAD374FC for ; Tue, 7 Nov 2023 15:05:07 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="n+aBCbFa" Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.8]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 38C1A5BA2; Tue, 7 Nov 2023 07:01:57 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1699369319; x=1730905319; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=FjYtM5RVeAt6DwS0DVP0GicyoumcVKYRPAacFq6P70U=; b=n+aBCbFaGaIIGtrobqmehdTqMhbXel4dPHrG9wPbpv368Cr45qhOH6Ep uzEvlQiAeDAHX5VdQNTZOzNHYGA6c00HjmKMmnedgqrOK6JtWRBtLtVfq qJR+srMExi0gcp3KYBYef5myinwL++VcTFCz6DZcZpy4/Ye4VXsLSzZ/b 0tclT7At+r3IBblJzd+CLoVkfCIoVVatr27u9wVYV4CBsU8AdzqqWtnOn vtpY/tJXWnUOnOBLocXnUGaNXVU7T3oGuHD/ZEVdVqU/tPEy/bOcvWP2Z ebSomsZ4GBeKp19shq07dAU6ajopvm0f7h7fagaMNbXJGo1MqH/in/jUW w==; X-IronPort-AV: E=McAfee;i="6600,9927,10887"; a="2462568" X-IronPort-AV: E=Sophos;i="6.03,284,1694761200"; d="scan'208";a="2462568" 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="10851555" 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 Subject: [PATCH v17 087/116] KVM: TDX: Handle EXIT_REASON_OTHER_SMI with MSMI Date: Tue, 7 Nov 2023 06:56:53 -0800 Message-Id: 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 When BIOS eMCA MCE-SMI morphing is enabled, the #MC is morphed to MSMI (Machine Check System Management Interrupt). Then the SMI causes TD exit with the read reason of EXIT_REASON_OTHER_SMI with MSMI bit set in the exit qualification to KVM instead of EXIT_REASON_EXCEPTION_NMI with MC exception. Handle EXIT_REASON_OTHER_SMI with MSMI bit set in the exit qualification as MCE(Machine Check Exception) happened during TD guest running. Signed-off-by: Isaku Yamahata --- arch/x86/kvm/vmx/tdx.c | 40 ++++++++++++++++++++++++++++++++++--- arch/x86/kvm/vmx/tdx_arch.h | 2 ++ 2 files changed, 39 insertions(+), 3 deletions(-) diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c index dc600ea7115f..317d8cf7f1cd 100644 --- a/arch/x86/kvm/vmx/tdx.c +++ b/arch/x86/kvm/vmx/tdx.c @@ -890,6 +890,30 @@ void tdx_handle_exit_irqoff(struct kvm_vcpu *vcpu) tdexit_intr_info(vcpu)); else if (exit_reason == EXIT_REASON_EXCEPTION_NMI) vmx_handle_exception_irqoff(vcpu, tdexit_intr_info(vcpu)); + else if (unlikely(tdx->exit_reason.non_recoverable || + tdx->exit_reason.error)) { + /* + * The only reason it gets EXIT_REASON_OTHER_SMI is there is an + * #MSMI(Machine Check System Management Interrupt) with + * exit_qualification bit 0 set in TD guest. + * The #MSMI is delivered right after SEAMCALL returns, + * and an #MC is delivered to host kernel after SMI handler + * returns. + * + * The #MC right after SEAMCALL is fixed up and skipped in #MC + * handler because it's an #MC happens in TD guest we cannot + * handle it with host's context. + * + * Call KVM's machine check handler explicitly here. + */ + if (tdx->exit_reason.basic == EXIT_REASON_OTHER_SMI) { + unsigned long exit_qual; + + exit_qual = tdexit_exit_qual(vcpu); + if (exit_qual & TD_EXIT_OTHER_SMI_IS_MSMI) + kvm_machine_check(); + } + } } static int tdx_handle_exception(struct kvm_vcpu *vcpu) @@ -1357,6 +1381,11 @@ int tdx_handle_exit(struct kvm_vcpu *vcpu, fastpath_t fastpath) exit_reason.full, exit_reason.basic, to_kvm_tdx(vcpu->kvm)->hkid, set_hkid_to_hpa(0, to_kvm_tdx(vcpu->kvm)->hkid)); + + /* + * tdx_handle_exit_irqoff() handled EXIT_REASON_OTHER_SMI. It + * must be handled before enabling preemption because it's #MC. + */ goto unhandled_exit; } @@ -1395,9 +1424,14 @@ int tdx_handle_exit(struct kvm_vcpu *vcpu, fastpath_t fastpath) return tdx_handle_ept_misconfig(vcpu); case EXIT_REASON_OTHER_SMI: /* - * If reach here, it's not a Machine Check System Management - * Interrupt(MSMI). #SMI is delivered and handled right after - * SEAMRET, nothing needs to be done in KVM. + * Unlike VMX, all the SMI in SEAM non-root mode (i.e. when + * TD guest vcpu is running) will cause TD exit to TDX module, + * then SEAMRET to KVM. Once it exits to KVM, SMI is delivered + * and handled right away. + * + * - If it's an Machine Check System Management Interrupt + * (MSMI), it's handled above due to non_recoverable bit set. + * - If it's not an MSMI, don't need to do anything here. */ return 1; default: diff --git a/arch/x86/kvm/vmx/tdx_arch.h b/arch/x86/kvm/vmx/tdx_arch.h index fc9a8898765c..9f93250d22b9 100644 --- a/arch/x86/kvm/vmx/tdx_arch.h +++ b/arch/x86/kvm/vmx/tdx_arch.h @@ -47,6 +47,8 @@ #define TDG_VP_VMCALL_REPORT_FATAL_ERROR 0x10003 #define TDG_VP_VMCALL_SETUP_EVENT_NOTIFY_INTERRUPT 0x10004 +#define TD_EXIT_OTHER_SMI_IS_MSMI BIT(1) + /* TDX control structure (TDR/TDCS/TDVPS) field access codes */ #define TDX_NON_ARCH BIT_ULL(63) #define TDX_CLASS_SHIFT 56