From 2c49db455ee27c72a680c9e4fad1c12433902ee3 Mon Sep 17 00:00:00 2001 From: Binbin Wu Date: Wed, 13 Sep 2023 20:42:17 +0800 Subject: KVM: x86: Add & use kvm_vcpu_is_legal_cr3() to check CR3's legality Add and use kvm_vcpu_is_legal_cr3() to check CR3's legality to provide a clear distinction between CR3 and GPA checks. This will allow exempting bits from kvm_vcpu_is_legal_cr3() without affecting general GPA checks, e.g. for upcoming features that will use high bits in CR3 for feature enabling. No functional change intended. Signed-off-by: Binbin Wu Tested-by: Xuelian Guo Link: https://lore.kernel.org/r/20230913124227.12574-7-binbin.wu@linux.intel.com Signed-off-by: Sean Christopherson --- arch/x86/kvm/svm/nested.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'arch/x86/kvm/svm/nested.c') diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c index 3fea8c47679e..90ca9489aab6 100644 --- a/arch/x86/kvm/svm/nested.c +++ b/arch/x86/kvm/svm/nested.c @@ -311,7 +311,7 @@ static bool __nested_vmcb_check_save(struct kvm_vcpu *vcpu, if ((save->efer & EFER_LME) && (save->cr0 & X86_CR0_PG)) { if (CC(!(save->cr4 & X86_CR4_PAE)) || CC(!(save->cr0 & X86_CR0_PE)) || - CC(kvm_vcpu_is_illegal_gpa(vcpu, save->cr3))) + CC(!kvm_vcpu_is_legal_cr3(vcpu, save->cr3))) return false; } @@ -520,7 +520,7 @@ static void nested_svm_transition_tlb_flush(struct kvm_vcpu *vcpu) static int nested_svm_load_cr3(struct kvm_vcpu *vcpu, unsigned long cr3, bool nested_npt, bool reload_pdptrs) { - if (CC(kvm_vcpu_is_illegal_gpa(vcpu, cr3))) + if (CC(!kvm_vcpu_is_legal_cr3(vcpu, cr3))) return -EINVAL; if (reload_pdptrs && !nested_npt && is_pae_paging(vcpu) && -- cgit From a484755ab2526ebdbe042397cdd6e427eb4b1a68 Mon Sep 17 00:00:00 2001 From: Sean Christopherson Date: Wed, 18 Oct 2023 12:41:03 -0700 Subject: Revert "nSVM: Check for reserved encodings of TLB_CONTROL in nested VMCB" Revert KVM's made-up consistency check on SVM's TLB control. The APM says that unsupported encodings are reserved, but the APM doesn't state that VMRUN checks for a supported encoding. Unless something is called out in "Canonicalization and Consistency Checks" or listed as MBZ (Must Be Zero), AMD behavior is typically to let software shoot itself in the foot. This reverts commit 174a921b6975ef959dd82ee9e8844067a62e3ec1. Fixes: 174a921b6975 ("nSVM: Check for reserved encodings of TLB_CONTROL in nested VMCB") Reported-by: Stefan Sterz Closes: https://lkml.kernel.org/r/b9915c9c-4cf6-051a-2d91-44cc6380f455%40proxmox.com Cc: stable@vger.kernel.org Reviewed-by: Maxim Levitsky Link: https://lore.kernel.org/r/20231018194104.1896415-2-seanjc@google.com Signed-off-by: Sean Christopherson --- arch/x86/kvm/svm/nested.c | 15 --------------- 1 file changed, 15 deletions(-) (limited to 'arch/x86/kvm/svm/nested.c') diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c index 3fea8c47679e..60891b9ce25f 100644 --- a/arch/x86/kvm/svm/nested.c +++ b/arch/x86/kvm/svm/nested.c @@ -247,18 +247,6 @@ static bool nested_svm_check_bitmap_pa(struct kvm_vcpu *vcpu, u64 pa, u32 size) kvm_vcpu_is_legal_gpa(vcpu, addr + size - 1); } -static bool nested_svm_check_tlb_ctl(struct kvm_vcpu *vcpu, u8 tlb_ctl) -{ - /* Nested FLUSHBYASID is not supported yet. */ - switch(tlb_ctl) { - case TLB_CONTROL_DO_NOTHING: - case TLB_CONTROL_FLUSH_ALL_ASID: - return true; - default: - return false; - } -} - static bool __nested_vmcb_check_controls(struct kvm_vcpu *vcpu, struct vmcb_ctrl_area_cached *control) { @@ -278,9 +266,6 @@ static bool __nested_vmcb_check_controls(struct kvm_vcpu *vcpu, IOPM_SIZE))) return false; - if (CC(!nested_svm_check_tlb_ctl(vcpu, control->tlb_ctl))) - return false; - if (CC((control->int_ctl & V_NMI_ENABLE_MASK) && !vmcb12_is_intercept(control, INTERCEPT_NMI))) { return false; -- cgit From af9d544a452114eb54638015544b884e1befd0fb Mon Sep 17 00:00:00 2001 From: Vitaly Kuznetsov Date: Tue, 5 Dec 2023 11:36:21 +0100 Subject: KVM: x86: Introduce helper to handle Hyper-V paravirt TLB flush requests As a preparation to making Hyper-V emulation optional, introduce a helper to handle pending KVM_REQ_HV_TLB_FLUSH requests. No functional change intended. Reviewed-by: Maxim Levitsky Tested-by: Jeremi Piotrowski Signed-off-by: Vitaly Kuznetsov Link: https://lore.kernel.org/r/20231205103630.1391318-8-vkuznets@redhat.com Signed-off-by: Sean Christopherson --- arch/x86/kvm/hyperv.h | 13 +++++++++++++ arch/x86/kvm/svm/nested.c | 10 ++-------- arch/x86/kvm/vmx/nested.c | 10 ++-------- 3 files changed, 17 insertions(+), 16 deletions(-) (limited to 'arch/x86/kvm/svm/nested.c') diff --git a/arch/x86/kvm/hyperv.h b/arch/x86/kvm/hyperv.h index 9d8fa6ba6341..77f6549aa5de 100644 --- a/arch/x86/kvm/hyperv.h +++ b/arch/x86/kvm/hyperv.h @@ -247,6 +247,19 @@ static inline int kvm_hv_verify_vp_assist(struct kvm_vcpu *vcpu) return kvm_hv_get_assist_page(vcpu); } +static inline void kvm_hv_nested_transtion_tlb_flush(struct kvm_vcpu *vcpu, + bool tdp_enabled) +{ + /* + * KVM_REQ_HV_TLB_FLUSH flushes entries from either L1's VP_ID or + * L2's VP_ID upon request from the guest. Make sure we check for + * pending entries in the right FIFO upon L1/L2 transition as these + * requests are put by other vCPUs asynchronously. + */ + if (to_hv_vcpu(vcpu) && tdp_enabled) + kvm_make_request(KVM_REQ_HV_TLB_FLUSH, vcpu); +} + int kvm_hv_vcpu_flush_tlb(struct kvm_vcpu *vcpu); #endif diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c index 3fea8c47679e..74c04102ef01 100644 --- a/arch/x86/kvm/svm/nested.c +++ b/arch/x86/kvm/svm/nested.c @@ -487,14 +487,8 @@ static void nested_save_pending_event_to_vmcb12(struct vcpu_svm *svm, static void nested_svm_transition_tlb_flush(struct kvm_vcpu *vcpu) { - /* - * KVM_REQ_HV_TLB_FLUSH flushes entries from either L1's VP_ID or - * L2's VP_ID upon request from the guest. Make sure we check for - * pending entries in the right FIFO upon L1/L2 transition as these - * requests are put by other vCPUs asynchronously. - */ - if (to_hv_vcpu(vcpu) && npt_enabled) - kvm_make_request(KVM_REQ_HV_TLB_FLUSH, vcpu); + /* Handle pending Hyper-V TLB flush requests */ + kvm_hv_nested_transtion_tlb_flush(vcpu, npt_enabled); /* * TODO: optimize unconditional TLB flush/MMU sync. A partial list of diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c index c5ec0ef51ff7..382c0746d069 100644 --- a/arch/x86/kvm/vmx/nested.c +++ b/arch/x86/kvm/vmx/nested.c @@ -1139,14 +1139,8 @@ static void nested_vmx_transition_tlb_flush(struct kvm_vcpu *vcpu, { struct vcpu_vmx *vmx = to_vmx(vcpu); - /* - * KVM_REQ_HV_TLB_FLUSH flushes entries from either L1's VP_ID or - * L2's VP_ID upon request from the guest. Make sure we check for - * pending entries in the right FIFO upon L1/L2 transition as these - * requests are put by other vCPUs asynchronously. - */ - if (to_hv_vcpu(vcpu) && enable_ept) - kvm_make_request(KVM_REQ_HV_TLB_FLUSH, vcpu); + /* Handle pending Hyper-V TLB flush requests */ + kvm_hv_nested_transtion_tlb_flush(vcpu, enable_ept); /* * If vmcs12 doesn't use VPID, L1 expects linear and combined mappings -- cgit From 017a99a966f1183e611f0b0fa6bec40160c81813 Mon Sep 17 00:00:00 2001 From: Vitaly Kuznetsov Date: Tue, 5 Dec 2023 11:36:30 +0100 Subject: KVM: nSVM: Hide more stuff under CONFIG_KVM_HYPERV/CONFIG_HYPERV 'struct hv_vmcb_enlightenments' in VMCB only make sense when either CONFIG_KVM_HYPERV or CONFIG_HYPERV is enabled. No functional change intended. Reviewed-by: Maxim Levitsky Tested-by: Jeremi Piotrowski Signed-off-by: Vitaly Kuznetsov Link: https://lore.kernel.org/r/20231205103630.1391318-17-vkuznets@redhat.com Signed-off-by: Sean Christopherson --- arch/x86/kvm/svm/nested.c | 20 ++++++++++++++------ arch/x86/kvm/svm/svm.h | 2 ++ 2 files changed, 16 insertions(+), 6 deletions(-) (limited to 'arch/x86/kvm/svm/nested.c') diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c index 74c04102ef01..20212aac050b 100644 --- a/arch/x86/kvm/svm/nested.c +++ b/arch/x86/kvm/svm/nested.c @@ -187,7 +187,6 @@ void recalc_intercepts(struct vcpu_svm *svm) */ static bool nested_svm_vmrun_msrpm(struct vcpu_svm *svm) { - struct hv_vmcb_enlightenments *hve = &svm->nested.ctl.hv_enlightenments; int i; /* @@ -198,11 +197,16 @@ static bool nested_svm_vmrun_msrpm(struct vcpu_svm *svm) * - Nested hypervisor (L1) is using Hyper-V emulation interface and * tells KVM (L0) there were no changes in MSR bitmap for L2. */ - if (!svm->nested.force_msr_bitmap_recalc && - kvm_hv_hypercall_enabled(&svm->vcpu) && - hve->hv_enlightenments_control.msr_bitmap && - (svm->nested.ctl.clean & BIT(HV_VMCB_NESTED_ENLIGHTENMENTS))) - goto set_msrpm_base_pa; +#ifdef CONFIG_KVM_HYPERV + if (!svm->nested.force_msr_bitmap_recalc) { + struct hv_vmcb_enlightenments *hve = &svm->nested.ctl.hv_enlightenments; + + if (kvm_hv_hypercall_enabled(&svm->vcpu) && + hve->hv_enlightenments_control.msr_bitmap && + (svm->nested.ctl.clean & BIT(HV_VMCB_NESTED_ENLIGHTENMENTS))) + goto set_msrpm_base_pa; + } +#endif if (!(vmcb12_is_intercept(&svm->nested.ctl, INTERCEPT_MSR_PROT))) return true; @@ -230,7 +234,9 @@ static bool nested_svm_vmrun_msrpm(struct vcpu_svm *svm) svm->nested.force_msr_bitmap_recalc = false; +#ifdef CONFIG_KVM_HYPERV set_msrpm_base_pa: +#endif svm->vmcb->control.msrpm_base_pa = __sme_set(__pa(svm->nested.msrpm)); return true; @@ -378,12 +384,14 @@ void __nested_copy_vmcb_control_to_cache(struct kvm_vcpu *vcpu, to->msrpm_base_pa &= ~0x0fffULL; to->iopm_base_pa &= ~0x0fffULL; +#ifdef CONFIG_KVM_HYPERV /* Hyper-V extensions (Enlightened VMCB) */ if (kvm_hv_hypercall_enabled(vcpu)) { to->clean = from->clean; memcpy(&to->hv_enlightenments, &from->hv_enlightenments, sizeof(to->hv_enlightenments)); } +#endif } void nested_copy_vmcb_control_to_cache(struct vcpu_svm *svm, diff --git a/arch/x86/kvm/svm/svm.h b/arch/x86/kvm/svm/svm.h index be67ab7fdd10..59adff7bbf55 100644 --- a/arch/x86/kvm/svm/svm.h +++ b/arch/x86/kvm/svm/svm.h @@ -148,7 +148,9 @@ struct vmcb_ctrl_area_cached { u64 virt_ext; u32 clean; union { +#if IS_ENABLED(CONFIG_HYPERV) || IS_ENABLED(CONFIG_KVM_HYPERV) struct hv_vmcb_enlightenments hv_enlightenments; +#endif u8 reserved_sw[32]; }; }; -- cgit