From patchwork Wed Nov 8 18:29:53 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Li, Xin3" X-Patchwork-Id: 743005 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A1166C04A92 for ; Wed, 8 Nov 2023 19:00:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232795AbjKHTAe (ORCPT ); Wed, 8 Nov 2023 14:00:34 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56704 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232663AbjKHTAa (ORCPT ); Wed, 8 Nov 2023 14:00:30 -0500 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.9]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 38F91211F; Wed, 8 Nov 2023 11:00:23 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1699470024; x=1731006024; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=cIflAivR9VCqnr0B5EZbFjn1ryM/tjY6g5E/Ilbnc7k=; b=DNtVIFN2FpOfmXbsAC+XDvhzvrv22e15/2v19iw+PG0ZVNkQoEH4cMT/ QRw2z4CV60M8Zr9l+kqcg7ZKL9N1spMoEBXMceE7K72+qP5P5o5b2pfPa VOQPr4IMBqFeByLOB8A5s+vNUgJfFE8Pi5h4UnQY3FYrYxkRpF7gUOr3Q 4bHw0RooBFg5as8A9A7rGDSn2/CdBUhdDLVHK7E8IyNTx+fQnlpK18t71 J+by/qbuJkt/UH4lsW/rukhtjzkZAObx76cgBEjCfMZstuPt8qbp8R0xB Sp+9ddIstJ/ONaZ+CCyIahUREMqiozlyW7Ojs/R0hHqYwaegUASwpRwki A==; X-IronPort-AV: E=McAfee;i="6600,9927,10888"; a="8486358" X-IronPort-AV: E=Sophos;i="6.03,287,1694761200"; d="scan'208";a="8486358" Received: from orviesa001.jf.intel.com ([10.64.159.141]) by orvoesa101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 08 Nov 2023 11:00:23 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.03,287,1694761200"; d="scan'208";a="10892480" Received: from unknown (HELO fred..) ([172.25.112.68]) by orviesa001.jf.intel.com with ESMTP; 08 Nov 2023 11:00:22 -0800 From: Xin Li To: kvm@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-hyperv@vger.kernel.org, linux-kselftest@vger.kernel.org Cc: seanjc@google.com, pbonzini@redhat.com, corbet@lwn.net, kys@microsoft.com, haiyangz@microsoft.com, wei.liu@kernel.org, decui@microsoft.com, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, vkuznets@redhat.com, peterz@infradead.org, ravi.v.shankar@intel.com Subject: [PATCH v1 13/23] KVM: VMX: Handle VMX nested exception for FRED Date: Wed, 8 Nov 2023 10:29:53 -0800 Message-ID: <20231108183003.5981-14-xin3.li@intel.com> X-Mailer: git-send-email 2.42.0 In-Reply-To: <20231108183003.5981-1-xin3.li@intel.com> References: <20231108183003.5981-1-xin3.li@intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org Set VMX nested exception bit in the VM-entry interruption information VMCS field when injecting a nested exception using FRED event delivery to ensure: 1) The nested exception is injected on a correct stack level. 2) The nested bit defined in FRED stack frame is set. The event stack level used by FRED event delivery depends on whether the event was a nested exception encountered during delivery of another event, because a nested exception is "regarded" as happening on ring 0. E.g., when #PF is configured to use stack level 1 in IA32_FRED_STKLVLS MSR: - nested #PF will be delivered on stack level 1 when triggered from user level. - normal #PF will be delivered on stack level 0 when triggered from user level. The VMX nested-exception support ensures the correct event stack level is chosen when a VM entry injects a nested exception. Tested-by: Shan Kang Signed-off-by: Xin Li --- arch/x86/include/asm/kvm_host.h | 6 ++++-- arch/x86/include/asm/vmx.h | 4 +++- arch/x86/kvm/svm/svm.c | 4 ++-- arch/x86/kvm/vmx/vmx.c | 26 +++++++++++++++++++++----- arch/x86/kvm/x86.c | 22 +++++++++++++--------- arch/x86/kvm/x86.h | 1 + 6 files changed, 44 insertions(+), 19 deletions(-) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 1e5a6d9439f8..2ae8cc83dbb3 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -721,6 +721,7 @@ struct kvm_queued_exception { u32 error_code; unsigned long payload; bool has_payload; + bool nested; }; struct kvm_vcpu_arch { @@ -2015,8 +2016,9 @@ int kvm_emulate_rdpmc(struct kvm_vcpu *vcpu); void kvm_queue_exception(struct kvm_vcpu *vcpu, unsigned nr); void kvm_queue_exception_e(struct kvm_vcpu *vcpu, unsigned nr, u32 error_code); void kvm_queue_exception_p(struct kvm_vcpu *vcpu, unsigned nr, unsigned long payload); -void kvm_requeue_exception(struct kvm_vcpu *vcpu, unsigned nr); -void kvm_requeue_exception_e(struct kvm_vcpu *vcpu, unsigned nr, u32 error_code); +void kvm_requeue_exception(struct kvm_vcpu *vcpu, unsigned nr, bool nested); +void kvm_requeue_exception_e(struct kvm_vcpu *vcpu, unsigned nr, + u32 error_code, bool nested); void kvm_inject_page_fault(struct kvm_vcpu *vcpu, struct x86_exception *fault); void kvm_inject_emulated_page_fault(struct kvm_vcpu *vcpu, struct x86_exception *fault); diff --git a/arch/x86/include/asm/vmx.h b/arch/x86/include/asm/vmx.h index 97729248e844..020dfd3f6b44 100644 --- a/arch/x86/include/asm/vmx.h +++ b/arch/x86/include/asm/vmx.h @@ -132,6 +132,7 @@ /* VMX_BASIC bits and bitmasks */ #define VMX_BASIC_32BIT_PHYS_ADDR_ONLY BIT_ULL(48) #define VMX_BASIC_INOUT BIT_ULL(54) +#define VMX_BASIC_NESTED_EXCEPTION BIT_ULL(58) /* VMX_MISC bits and bitmasks */ #define VMX_MISC_INTEL_PT BIT_ULL(14) @@ -404,8 +405,9 @@ enum vmcs_field { #define INTR_INFO_INTR_TYPE_MASK 0x700 /* 10:8 */ #define INTR_INFO_DELIVER_CODE_MASK 0x800 /* 11 */ #define INTR_INFO_UNBLOCK_NMI 0x1000 /* 12 */ +#define INTR_INFO_NESTED_EXCEPTION_MASK 0x2000 /* 13 */ #define INTR_INFO_VALID_MASK 0x80000000 /* 31 */ -#define INTR_INFO_RESVD_BITS_MASK 0x7ffff000 +#define INTR_INFO_RESVD_BITS_MASK 0x7fffd000 #define VECTORING_INFO_VECTOR_MASK INTR_INFO_VECTOR_MASK #define VECTORING_INFO_TYPE_MASK INTR_INFO_INTR_TYPE_MASK diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c index 712146312358..78a9ff5cfcad 100644 --- a/arch/x86/kvm/svm/svm.c +++ b/arch/x86/kvm/svm/svm.c @@ -4047,10 +4047,10 @@ static void svm_complete_interrupts(struct kvm_vcpu *vcpu) if (exitintinfo & SVM_EXITINTINFO_VALID_ERR) { u32 err = svm->vmcb->control.exit_int_info_err; - kvm_requeue_exception_e(vcpu, vector, err); + kvm_requeue_exception_e(vcpu, vector, err, false); } else - kvm_requeue_exception(vcpu, vector); + kvm_requeue_exception(vcpu, vector, false); break; case SVM_EXITINTINFO_TYPE_INTR: kvm_queue_interrupt(vcpu, vector, false); diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index 67fd4a56d031..518e68ee5a0d 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -1901,6 +1901,8 @@ static void vmx_inject_exception(struct kvm_vcpu *vcpu) event_data = vcpu->arch.guest_fpu.xfd_err; vmcs_write64(INJECTED_EVENT_DATA, event_data); + + intr_info |= ex->nested ? INTR_INFO_NESTED_EXCEPTION_MASK : 0; } } @@ -2851,6 +2853,19 @@ static int setup_vmcs_config(struct vmcs_config *vmcs_conf, /* IA-32 SDM Vol 3B: 64-bit CPUs always have VMX_BASIC_MSR[48]==0. */ if (basic_msr & VMX_BASIC_32BIT_PHYS_ADDR_ONLY) return -EIO; + + /* + * FRED draft Spec 5.0 Section 9.2: + * + * Any processor that enumerates support for FRED transitions + * will also enumerate VMX nested-exception support. + */ + if (cpu_feature_enabled(X86_FEATURE_FRED) && + !(basic_msr & VMX_BASIC_NESTED_EXCEPTION)) { + pr_warn_once("FRED enabled but no VMX nested-exception support\n"); + if (error_on_inconsistent_vmcs_config) + return -EIO; + } #endif /* Require Write-Back (WB) memory type for VMCS accesses. */ @@ -7313,11 +7328,12 @@ static void __vmx_complete_interrupts(struct kvm_vcpu *vcpu, } } - if (idt_vectoring_info & VECTORING_INFO_DELIVER_CODE_MASK) { - u32 err = vmcs_read32(error_code_field); - kvm_requeue_exception_e(vcpu, vector, err); - } else - kvm_requeue_exception(vcpu, vector); + if (idt_vectoring_info & VECTORING_INFO_DELIVER_CODE_MASK) + kvm_requeue_exception_e(vcpu, vector, vmcs_read32(error_code_field), + idt_vectoring_info & INTR_INFO_NESTED_EXCEPTION_MASK); + else + kvm_requeue_exception(vcpu, vector, + idt_vectoring_info & INTR_INFO_NESTED_EXCEPTION_MASK); break; case INTR_TYPE_SOFT_INTR: vcpu->arch.event_exit_inst_len = vmcs_read32(instr_len_field); diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index d190bfc63fc4..51c07730f1b6 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -645,7 +645,8 @@ static void kvm_leave_nested(struct kvm_vcpu *vcpu) static void kvm_multiple_exception(struct kvm_vcpu *vcpu, unsigned nr, bool has_error, u32 error_code, - bool has_payload, unsigned long payload, bool reinject) + bool has_payload, unsigned long payload, + bool reinject, bool nested) { u32 prev_nr; int class1, class2; @@ -678,6 +679,7 @@ static void kvm_multiple_exception(struct kvm_vcpu *vcpu, */ WARN_ON_ONCE(kvm_is_exception_pending(vcpu)); vcpu->arch.exception.injected = true; + vcpu->arch.exception.nested = nested; if (WARN_ON_ONCE(has_payload)) { /* * For a reinjected event, KVM delivers its @@ -727,6 +729,8 @@ static void kvm_multiple_exception(struct kvm_vcpu *vcpu, kvm_queue_exception_e(vcpu, DF_VECTOR, 0); } else { + vcpu->arch.exception.nested = true; + /* replace previous exception with a new one in a hope that instruction re-execution will regenerate lost exception */ @@ -736,20 +740,20 @@ static void kvm_multiple_exception(struct kvm_vcpu *vcpu, void kvm_queue_exception(struct kvm_vcpu *vcpu, unsigned nr) { - kvm_multiple_exception(vcpu, nr, false, 0, false, 0, false); + kvm_multiple_exception(vcpu, nr, false, 0, false, 0, false, false); } EXPORT_SYMBOL_GPL(kvm_queue_exception); -void kvm_requeue_exception(struct kvm_vcpu *vcpu, unsigned nr) +void kvm_requeue_exception(struct kvm_vcpu *vcpu, unsigned nr, bool nested) { - kvm_multiple_exception(vcpu, nr, false, 0, false, 0, true); + kvm_multiple_exception(vcpu, nr, false, 0, false, 0, true, nested); } EXPORT_SYMBOL_GPL(kvm_requeue_exception); void kvm_queue_exception_p(struct kvm_vcpu *vcpu, unsigned nr, unsigned long payload) { - kvm_multiple_exception(vcpu, nr, false, 0, true, payload, false); + kvm_multiple_exception(vcpu, nr, false, 0, true, payload, false, false); } EXPORT_SYMBOL_GPL(kvm_queue_exception_p); @@ -757,7 +761,7 @@ static void kvm_queue_exception_e_p(struct kvm_vcpu *vcpu, unsigned nr, u32 error_code, unsigned long payload) { kvm_multiple_exception(vcpu, nr, true, error_code, - true, payload, false); + true, payload, false, false); } int kvm_complete_insn_gp(struct kvm_vcpu *vcpu, int err) @@ -829,13 +833,13 @@ void kvm_inject_nmi(struct kvm_vcpu *vcpu) void kvm_queue_exception_e(struct kvm_vcpu *vcpu, unsigned nr, u32 error_code) { - kvm_multiple_exception(vcpu, nr, true, error_code, false, 0, false); + kvm_multiple_exception(vcpu, nr, true, error_code, false, 0, false, false); } EXPORT_SYMBOL_GPL(kvm_queue_exception_e); -void kvm_requeue_exception_e(struct kvm_vcpu *vcpu, unsigned nr, u32 error_code) +void kvm_requeue_exception_e(struct kvm_vcpu *vcpu, unsigned nr, u32 error_code, bool nested) { - kvm_multiple_exception(vcpu, nr, true, error_code, false, 0, true); + kvm_multiple_exception(vcpu, nr, true, error_code, false, 0, true, nested); } EXPORT_SYMBOL_GPL(kvm_requeue_exception_e); diff --git a/arch/x86/kvm/x86.h b/arch/x86/kvm/x86.h index 60da8cbe6759..63e543c6834b 100644 --- a/arch/x86/kvm/x86.h +++ b/arch/x86/kvm/x86.h @@ -108,6 +108,7 @@ static inline void kvm_clear_exception_queue(struct kvm_vcpu *vcpu) { vcpu->arch.exception.pending = false; vcpu->arch.exception.injected = false; + vcpu->arch.exception.nested = false; vcpu->arch.exception_vmexit.pending = false; }