// SPDX-License-Identifier: GPL-2.0-only /* * Kernel-based Virtual Machine driver for Linux * * AMD SVM support * * Copyright (C) 2006 Qumranet, Inc. * Copyright 2010 Red Hat, Inc. and/or its affiliates. * * Authors: * Yaniv Kamay * Avi Kivity */ #define pr_fmt(fmt) "SVM: " fmt #include #include #include #include #include #include "kvm_emulate.h" #include "trace.h" #include "mmu.h" #include "x86.h" #include "cpuid.h" #include "lapic.h" #include "svm.h" #define CC KVM_NESTED_VMENTER_CONSISTENCY_CHECK static void nested_svm_inject_npf_exit(struct kvm_vcpu *vcpu, struct x86_exception *fault) { struct vcpu_svm *svm = to_svm(vcpu); if (svm->vmcb->control.exit_code != SVM_EXIT_NPF) { /* * TODO: track the cause of the nested page fault, and * correctly fill in the high bits of exit_info_1. */ svm->vmcb->control.exit_code = SVM_EXIT_NPF; svm->vmcb->control.exit_code_hi = 0; svm->vmcb->control.exit_info_1 = (1ULL << 32); svm->vmcb->control.exit_info_2 = fault->address; } svm->vmcb->control.exit_info_1 &= ~0xffffffffULL; svm->vmcb->control.exit_info_1 |= fault->error_code; nested_svm_vmexit(svm); } static void svm_inject_page_fault_nested(struct kvm_vcpu *vcpu, struct x86_exception *fault) { struct vcpu_svm *svm = to_svm(vcpu); WARN_ON(!is_guest_mode(vcpu)); if (vmcb_is_intercept(&svm->nested.ctl, INTERCEPT_EXCEPTION_OFFSET + PF_VECTOR) && !svm->nested.nested_run_pending) { svm->vmcb->control.exit_code = SVM_EXIT_EXCP_BASE + PF_VECTOR; svm->vmcb->control.exit_code_hi = 0; svm->vmcb->control.exit_info_1 = fault->error_code; svm->vmcb->control.exit_info_2 = fault->address; nested_svm_vmexit(svm); } else { kvm_inject_page_fault(vcpu, fault); } } static u64 nested_svm_get_tdp_pdptr(struct kvm_vcpu *vcpu, int index) { struct vcpu_svm *svm = to_svm(vcpu); u64 cr3 = svm->nested.ctl.nested_cr3; u64 pdpte; int ret; ret = kvm_vcpu_read_guest_page(vcpu, gpa_to_gfn(cr3), &pdpte, offset_in_page(cr3) + index * 8, 8); if (ret) return 0; return pdpte; } static unsigned long nested_svm_get_tdp_cr3(struct kvm_vcpu *vcpu) { struct vcpu_svm *svm = to_svm(vcpu); return svm->nested.ctl.nested_cr3; } static void nested_svm_init_mmu_context(struct kvm_vcpu *vcpu) { struct vcpu_svm *svm = to_svm(vcpu); WARN_ON(mmu_is_nested(vcpu)); vcpu->arch.mmu = &vcpu->arch.guest_mmu; kvm_init_shadow_npt_mmu(vcpu, X86_CR0_PG, svm->vmcb01.ptr->save.cr4, svm->vmcb01.ptr->save.efer, svm->nested.ctl.nested_cr3); vcpu->arch.mmu->get_guest_pgd = nested_svm_get_tdp_cr3; vcpu->arch.mmu->get_pdptr = nested_svm_get_tdp_pdptr; vcpu->arch.mmu->inject_page_fault = nested_svm_inject_npf_exit; reset_shadow_zero_bits_mask(vcpu, vcpu->arch.mmu); vcpu->arch.walk_mmu = &vcpu->arch.nested_mmu; } static void nested_svm_uninit_mmu_context(struct kvm_vcpu *vcpu) { vcpu->arch.mmu = &vcpu->arch.root_mmu; vcpu->arch.walk_mmu = &vcpu->arch.root_mmu; } void recalc_intercepts(struct vcpu_svm *svm) { struct vmcb_control_area *c, *h, *g; unsigned int i; vmcb_mark_dirty(svm->vmcb, VMCB_INTERCEPTS); if (!is_guest_mode(&svm->vcpu)) return; c = &svm->vmcb->control; h = &svm->vmcb01.ptr->control; g = &svm->nested.ctl; for (i = 0; i < MAX_INTERCEPT; i++) c->intercepts[i] = h->intercepts[i]; if (g->int_ctl & V_INTR_MASKING_MASK) { /* We only want the cr8 intercept bits of L1 */ vmcb_clr_intercept(c, INTERCEPT_CR8_READ); vmcb_clr_intercept(c, INTERCEPT_CR8_WRITE); /* * Once running L2 with HF_VINTR_MASK, EFLAGS.IF does not * affect any interrupt we may want to inject; therefore, * interrupt window vmexits are irrelevant to L0. */ vmcb_clr_intercept(c, INTERCEPT_VINTR); } /* We don't want to see VMMCALLs from a nested guest */ vmcb_clr_intercept(c, INTERCEPT_VMMCALL); for (i = 0; i < MAX_INTERCEPT; i++) c->intercepts[i] |= g->intercepts[i]; } static void copy_vmcb_control_area(struct vmcb_control_area *dst, struct vmcb_control_area *from) { unsigned int i; for (i = 0; i < MAX_INTERCEPT; i++) dst->intercepts[i] = from->intercepts[i]; dst->iopm_base_pa = from->iopm_base_pa; dst->msrpm_base_pa = from->msrpm_base_pa; dst->tsc_offset = from->tsc_offset; /* asid not copied, it is handled manually for svm->vmcb. */ dst->tlb_ctl = from->tlb_ctl; dst->int_ctl = from->int_ctl; dst->int_vector = from->int_vector; dst->int_state = from->int_state; dst->exit_code = from->exit_code; dst->exit_code_hi = from->exit_code_hi; dst->exit_info_1 = from->exit_info_1; dst->exit_info_2 = from->exit_info_2; dst->exit_int_info = from->exit_int_info; dst->exit_int_info_err = from->exit_int_info_err; dst->nested_ctl = from->nested_ctl; dst->event_inj = from->event_inj; dst->event_inj_err = from->event_inj_err; dst->nested_cr3 = from->nested_cr3; dst->virt_ext = from->virt_ext; dst->pause_filter_count = from->pause_filter_count; dst->pause_filter_thresh = from->pause_filter_thresh; } static bool nested_svm_vmrun_msrpm(struct vcpu_svm *svm) { /* * This function merges the msr permission bitmaps of kvm and the * nested vmcb. It is optimized in that it only merges the parts where * the kvm msr permission bitmap may contain zero bits */ int i; if (!(vmcb_is_intercept(&svm->nested.ctl, INTERCEPT_MSR_PROT))) return true; for (i = 0; i < MSRPM_OFFSETS; i++) { u32 value, p; u64 offset; if (msrpm_offsets[i] == 0xffffffff) break; p = msrpm_offsets[i]; offset = svm->nested.ctl.msrpm_base_pa + (p * 4); if (kvm_vcpu_read_guest(&svm->vcpu, offset, &value, 4)) return false; svm->nested.msrpm[p] = svm->msrpm[p] | value; } svm->vmcb->control.msrpm_base_pa = __sme_set(__pa(svm->nested.msrpm)); return true; } /* * Bits 11:0 of bitmap address are ignored by hardware */ static bool nested_svm_check_bitmap_pa(struct kvm_vcpu *vcpu, u64 pa, u32 size) { u64 addr = PAGE_ALIGN(pa); return kvm_vcpu_is_legal_gpa(vcpu, addr) && kvm_vcpu_is_legal_gpa(vcpu, addr + size - 1); } static bool nested_vmcb_check_controls(struct kvm_vcpu *vcpu, struct vmcb_control_area *control) { if (CC(!vmcb_is_intercept(control, INTERCEPT_VMRUN))) return false; if (CC(control->asid == 0)) return false; if (CC((control->nested_ctl & SVM_NESTED_CTL_NP_ENABLE) && !npt_enabled)) return false; if (CC(!nested_svm_check_bitmap_pa(vcpu, control->msrpm_base_pa, MSRPM_SIZE))) return false; if (CC(!nested_svm_check_bitmap_pa(vcpu, control->iopm_base_pa, IOPM_SIZE))) return false; return true; } static bool nested_vmcb_check_cr3_cr4(struct kvm_vcpu *vcpu, struct vmcb_save_area *save) { /* * These checks are also performed by KVM_SET_SREGS, * except that EFER.LMA is not checked by SVM against * CR0.PG && EFER.LME. */ 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))) return false; } if (CC(!kvm_is_valid_cr4(vcpu, save->cr4))) return false; return true; } /* Common checks that apply to both L1 and L2 state. */ static bool nested_vmcb_valid_sregs(struct kvm_vcpu *vcpu, struct vmcb_save_area *save) { /* * FIXME: these should be done after copying the fields, * to avoid TOC/TOU races. For these save area checks * the possible damage is limited since kvm_set_cr0 and * kvm_set_cr4 handle failure; EFER_SVME is an exception * so it is force-set later in nested_prepare_vmcb_save. */ if (CC(!(save->efer & EFER_SVME))) return false; if (CC((save->cr0 & X86_CR0_CD) == 0 && (save->cr0 & X86_CR0_NW)) || CC(save->cr0 & ~0xffffffffULL)) return false; if (CC(!kvm_dr6_valid(save->dr6)) || CC(!kvm_dr7_valid(save->dr7))) return false; if (!nested_vmcb_check_cr3_cr4(vcpu, save)) return false; if (CC(!kvm_valid_efer(vcpu, save->efer))) return false; return true; } static void nested_load_control_from_vmcb12(struct vcpu_svm *svm, struct vmcb_control_area *control) { copy_vmcb_control_area(&svm->nested.ctl, control); /* Copy it here because nested_svm_check_controls will check it. */ svm->nested.ctl.asid = control->asid; svm->nested.ctl.msrpm_base_pa &= ~0x0fffULL; svm->nested.ctl.iopm_base_pa &= ~0x0fffULL; } /* * Synchronize fields that are written by the processor, so that * they can be copied back into the vmcb12. */ void nested_sync_control_from_vmcb02(struct vcpu_svm *svm) { u32 mask; svm->nested.ctl.event_inj = svm->vmcb->control.event_inj; svm->nested.ctl.event_inj_err = svm->vmcb->control.event_inj_err; /* Only a few fields of int_ctl are written by the processor. */ mask = V_IRQ_MASK | V_TPR_MASK; if (!(svm->nested.ctl.int_ctl & V_INTR_MASKING_MASK) && svm_is_intercept(svm, INTERCEPT_VINTR)) { /* * In order to request an interrupt window, L0 is usurping * svm->vmcb->control.int_ctl and possibly setting V_IRQ * even if it was clear in L1's VMCB. Restoring it would be * wrong. However, in this case V_IRQ will remain true until * interrupt_window_interception calls svm_clear_vintr and * restores int_ctl. We can just leave it aside. */ mask &= ~V_IRQ_MASK; } svm->nested.ctl.int_ctl &= ~mask; svm->nested.ctl.int_ctl |= svm->vmcb->control.int_ctl & mask; } /* * Transfer any event that L0 or L1 wanted to inject into L2 to * EXIT_INT_INFO. */ static void nested_save_pending_event_to_vmcb12(struct vcpu_svm *svm, struct vmcb *vmcb12) { struct kvm_vcpu *vcpu = &svm->vcpu; u32 exit_int_info = 0; unsigned int nr; if (vcpu->arch.exception.injected) { nr = vcpu->arch.exception.nr; exit_int_info = nr | SVM_EVTINJ_VALID | SVM_EVTINJ_TYPE_EXEPT; if (vcpu->arch.exception.has_error_code) { exit_int_info |= SVM_EVTINJ_VALID_ERR; vmcb12->control.exit_int_info_err = vcpu->arch.exception.error_code; } } else if (vcpu->arch.nmi_injected) { exit_int_info = SVM_EVTINJ_VALID | SVM_EVTINJ_TYPE_NMI; } else if (vcpu->arch.interrupt.injected) { nr = vcpu->arch.interrupt.nr; exit_int_info = nr | SVM_EVTINJ_VALID; if (vcpu->arch.interrupt.soft) exit_int_info |= SVM_EVTINJ_TYPE_SOFT; else exit_int_info |= SVM_EVTINJ_TYPE_INTR; } vmcb12->control.exit_int_info = exit_int_info; } static inline bool nested_npt_enabled(struct vcpu_svm *svm) { return svm->nested.ctl.nested_ctl & SVM_NESTED_CTL_NP_ENABLE; } /* * Load guest's/host's cr3 on nested vmentry or vmexit. @nested_npt is true * if we are emulating VM-Entry into a guest with NPT enabled. */ static int nested_svm_load_cr3(struct kvm_vcpu *vcpu, unsigned long cr3, bool nested_npt) { if (CC(kvm_vcpu_is_illegal_gpa(vcpu, cr3))) return -EINVAL; if (!nested_npt && is_pae_paging(vcpu) && (cr3 != kvm_read_cr3(vcpu) || pdptrs_changed(vcpu))) { if (CC(!load_pdptrs(vcpu, vcpu->arch.walk_mmu, cr3))) return -EINVAL; } /* * TODO: optimize unconditional TLB flush/MMU sync here and in * kvm_init_shadow_npt_mmu(). */ if (!nested_npt) kvm_mmu_new_pgd(vcpu, cr3, false, false); vcpu->arch.cr3 = cr3; kvm_register_mark_available(vcpu, VCPU_EXREG_CR3); kvm_init_mmu(vcpu, false); return 0; } void nested_vmcb02_compute_g_pat(struct vcpu_svm *svm) { if (!svm->nested.vmcb02.ptr) return; /* FIXME: merge g_pat from vmcb01 and vmcb12. */ svm->nested.vmcb02.ptr->save.g_pat = svm->vmcb01.ptr->save.g_pat; } static void nested_vmcb02_prepare_save(struct vcpu_svm *svm, struct vmcb *vmcb12) { bool new_vmcb12 = false; nested_vmcb02_compute_g_pat(svm); /* Load the nested guest state */ if (svm->nested.vmcb12_gpa != svm->nested.last_vmcb12_gpa) { new_vmcb12 = true; svm->nested.last_vmcb12_gpa = svm->nested.vmcb12_gpa; } if (unlikely(new_vmcb12 || vmcb_is_dirty(vmcb12, VMCB_SEG))) { svm->vmcb->save.es = vmcb12->save.es; svm->vmcb->save.cs = vmcb12->save.cs; svm->vmcb->save.ss = vmcb12->save.ss; svm->vmcb->save.ds = vmcb12->save.ds; svm->vmcb->save.cpl = vmcb12->save.cpl; vmcb_mark_dirty(svm->vmcb, VMCB_SEG); } if (unlikely(new_vmcb12 || vmcb_is_dirty(vmcb12, VMCB_DT))) { svm->vmcb->save.gdtr = vmcb12->save.gdtr; svm->vmcb->save.idtr = vmcb12->save.idtr; vmcb_mark_dirty(svm->vmcb, VMCB_DT); } kvm_set_rflags(&svm->vcpu, vmcb12->save.rflags | X86_EFLAGS_FIXED); /* * Force-set EFER_SVME even though it is checked earlier on the * VMCB12, because the guest can flip the bit between the check * and now. Clearing EFER_SVME would call svm_free_nested. */ svm_set_efer(&svm->vcpu, vmcb12->save.efer | EFER_SVME); svm_set_cr0(&svm->vcpu, vmcb12->save.cr0); svm_set_cr4(&svm->vcpu, vmcb12->save.cr4); svm->vcpu.arch.cr2 = vmcb12->save.cr2; kvm_rax_write(&svm->vcpu, vmcb12->save.rax); kvm_rsp_write(&svm->vcpu, vmcb12->save.rsp); kvm_rip_write(&svm->vcpu, vmcb12->save.rip); /* In case we don't even reach vcpu_run, the fields are not updated */ svm->vmcb->save.rax = vmcb12->save.rax; svm->vmcb->save.rsp = vmcb12->save.rsp; svm->vmcb->save.rip = vmcb12->save.rip; /* These bits will be set properly on the first execution when new_vmc12 is true */ if (unlikely(new_vmcb12 || vmcb_is_dirty(vmcb12, VMCB_DR))) { svm->vmcb->save.dr7 = vmcb12->save.dr7 | DR7_FIXED_1; svm->vcpu.arch.dr6 = vmcb12->save.dr6 | DR6_ACTIVE_LOW; vmcb_mark_dirty(svm->vmcb, VMCB_DR); } } static void nested_vmcb02_prepare_control(struct vcpu_svm *svm) { const u32 mask = V_INTR_MASKING_MASK | V_GIF_ENABLE_MASK | V_GIF_MASK; /* * Filled at exit: exit_code, exit_code_hi, exit_info_1, exit_info_2, * exit_int_info, exit_int_info_err, next_rip, insn_len, insn_bytes. */ /* * Also covers avic_vapic_bar, avic_backing_page, avic_logical_id, * avic_physical_id. */ WARN_ON(svm->vmcb01.ptr->control.int_ctl & AVIC_ENABLE_MASK); /* Copied from vmcb01. msrpm_base can be overwritten later. */ svm->vmcb->control.nested_ctl = svm->vmcb01.ptr->control.nested_ctl; svm->vmcb->control.iopm_base_pa = svm->vmcb01.ptr->control.iopm_base_pa; svm->vmcb->control.msrpm_base_pa = svm->vmcb01.ptr->control.msrpm_base_pa; /* Done at vmrun: asid. */ /* Also overwritten later if necessary. */ svm->vmcb->control.tlb_ctl = TLB_CONTROL_DO_NOTHING; /* nested_cr3. */ if (nested_npt_enabled(svm)) nested_svm_init_mmu_context(&svm->vcpu); svm->vmcb->control.tsc_offset = svm->vcpu.arch.tsc_offset = svm->vcpu.arch.l1_tsc_offset + svm->nested.ctl.tsc_offset; svm->vmcb->control.int_ctl = (svm->nested.ctl.int_ctl & ~mask) | (svm->vmcb01.ptr->control.int_ctl & mask); svm->vmcb->control.virt_ext = svm->nested.ctl.virt_ext; svm->vmcb->control.int_vector = svm->nested.ctl.int_vector; svm->vmcb->control.int_state = svm->nested.ctl.int_state; svm->vmcb->control.event_inj = svm->nested.ctl.event_inj; svm->vmcb->control.event_inj_err = svm->nested.ctl.event_inj_err; svm->vmcb->control.pause_filter_count = svm->nested.ctl.pause_filter_count; svm->vmcb->control.pause_filter_thresh = svm->nested.ctl.pause_filter_thresh; /* Enter Guest-Mode */ enter_guest_mode(&svm->vcpu); /* * Merge guest and host intercepts - must be called with vcpu in * guest-mode to take effect. */ recalc_intercepts(svm); } static void nested_svm_copy_common_state(struct vmcb *from_vmcb, struct vmcb *to_vmcb) { /* * Some VMCB state is shared between L1 and L2 and thus has to be * moved at the time of nested vmrun and vmexit. * * VMLOAD/VMSAVE state would also belong in this category, but KVM * always performs VMLOAD and VMSAVE from the VMCB01. */ to_vmcb->save.spec_ctrl = from_vmcb->save.spec_ctrl; } int enter_svm_guest_mode(struct kvm_vcpu *vcpu, u64 vmcb12_gpa, struct vmcb *vmcb12) { struct vcpu_svm *svm = to_svm(vcpu); int ret; trace_kvm_nested_vmrun(svm->vmcb->save.rip, vmcb12_gpa, vmcb12->save.rip, vmcb12->control.int_ctl, vmcb12->control.event_inj, vmcb12->control.nested_ctl); trace_kvm_nested_intercepts(vmcb12->control.intercepts[INTERCEPT_CR] & 0xffff, vmcb12->control.intercepts[INTERCEPT_CR] >> 16, vmcb12->control.intercepts[INTERCEPT_EXCEPTION], vmcb12->control.intercepts[INTERCEPT_WORD3], vmcb12->control.intercepts[INTERCEPT_WORD4], vmcb12->control.intercepts[INTERCEPT_WORD5]); svm->nested.vmcb12_gpa = vmcb12_gpa; WARN_ON(svm->vmcb == svm->nested.vmcb02.ptr); nested_svm_copy_common_state(svm->vmcb01.ptr, svm->nested.vmcb02.ptr); svm_switch_vmcb(svm, &svm->nested.vmcb02); nested_vmcb02_prepare_control(svm); nested_vmcb02_prepare_save(svm, vmcb12); ret = nested_svm_load_cr3(&svm->vcpu, vmcb12->save.cr3, nested_npt_enabled(svm)); if (ret) return ret; if (!npt_enabled) vcpu->arch.mmu->inject_page_fault = svm_inject_page_fault_nested; svm_set_gif(svm, true); return 0; } int nested_svm_vmrun(struct kvm_vcpu *vcpu) { struct vcpu_svm *svm = to_svm(vcpu); int ret; struct vmcb *vmcb12; struct kvm_host_map map; u64 vmcb12_gpa; ++vcpu->stat.nested_run; if (is_smm(vcpu)) { kvm_queue_exception(vcpu, UD_VECTOR); return 1; } vmcb12_gpa = svm->vmcb->save.rax; ret = kvm_vcpu_map(vcpu, gpa_to_gfn(vmcb12_gpa), &map); if (ret == -EINVAL) { kvm_inject_gp(vcpu, 0); return 1; } else if (ret) { return kvm_skip_emulated_instruction(vcpu); } ret = kvm_skip_emulated_instruction(vcpu); vmcb12 = map.hva; if (WARN_ON_ONCE(!svm->nested.initialized)) return -EINVAL; nested_load_control_from_vmcb12(svm, &vmcb12->control); if (!nested_vmcb_valid_sregs(vcpu, &vmcb12->save) || !nested_vmcb_check_controls(vcpu, &svm->nested.ctl)) { vmcb12->control.exit_code = SVM_EXIT_ERR; vmcb12->control.exit_code_hi = 0; vmcb12->control.exit_info_1 = 0; vmcb12->control.exit_info_2 = 0; goto out; } /* Clear internal status */ kvm_clear_exception_queue(vcpu); kvm_clear_interrupt_queue(vcpu); /* * Since vmcb01 is not in use, we can use it to store some of the L1 * state. */ svm->vmcb01.ptr->save.efer = vcpu->arch.efer; svm->vmcb01.ptr->save.cr0 = kvm_read_cr0(vcpu); svm->vmcb01.ptr->save.cr4 = vcpu->arch.cr4; svm->vmcb01.ptr->save.rflags = kvm_get_rflags(vcpu); svm->vmcb01.ptr->save.rip = kvm_rip_read(vcpu); if (!npt_enabled) svm->vmcb01.ptr->save.cr3 = kvm_read_cr3(vcpu); svm->nested.nested_run_pending = 1; if (enter_svm_guest_mode(vcpu, vmcb12_gpa, vmcb12)) goto out_exit_err; if (nested_svm_vmrun_msrpm(svm)) goto out; out_exit_err: svm->nested.nested_run_pending = 0; svm->vmcb->control.exit_code = SVM_EXIT_ERR; svm->vmcb->control.exit_code_hi = 0; svm->vmcb->control.exit_info_1 = 0; svm->vmcb->control.exit_info_2 = 0; nested_svm_vmexit(svm); out: kvm_vcpu_unmap(vcpu, &map, true); return ret; } void nested_svm_vmloadsave(struct vmcb *from_vmcb, struct vmcb *to_vmcb) { to_vmcb->save.fs = from_vmcb->save.fs; to_vmcb->save.gs = from_vmcb->save.gs; to_vmcb->save.tr = from_vmcb->save.tr; to_vmcb->save.ldtr = from_vmcb->save.ldtr; to_vmcb->save.kernel_gs_base = from_vmcb->save.kernel_gs_base; to_vmcb->save.star = from_vmcb->save.star; to_vmcb->save.lstar = from_vmcb->save.lstar; to_vmcb->save.cstar = from_vmcb->save.cstar; to_vmcb->save.sfmask = from_vmcb->save.sfmask; to_vmcb->save.sysenter_cs = from_vmcb->save.sysenter_cs; to_vmcb->save.sysenter_esp = from_vmcb->save.sysenter_esp; to_vmcb->save.sysenter_eip = from_vmcb->save.sysenter_eip; } int nested_svm_vmexit(struct vcpu_svm *svm) { struct kvm_vcpu *vcpu = &svm->vcpu; struct vmcb *vmcb12; struct vmcb *vmcb = svm->vmcb; struct kvm_host_map map; int rc; /* Triple faults in L2 should never escape. */ WARN_ON_ONCE(kvm_check_request(KVM_REQ_TRIPLE_FAULT, vcpu)); rc = kvm_vcpu_map(vcpu, gpa_to_gfn(svm->nested.vmcb12_gpa), &map); if (rc) { if (rc == -EINVAL) kvm_inject_gp(vcpu, 0); return 1; } vmcb12 = map.hva; /* Exit Guest-Mode */ leave_guest_mode(vcpu); svm->nested.vmcb12_gpa = 0; WARN_ON_ONCE(svm->nested.nested_run_pending); kvm_clear_request(KVM_REQ_GET_NESTED_STATE_PAGES, vcpu); /* in case we halted in L2 */ svm->vcpu.arch.mp_state = KVM_MP_STATE_RUNNABLE; /* Give the current vmcb to the guest */ vmcb12->save.es = vmcb->save.es; vmcb12->save.cs = vmcb->save.cs; vmcb12->save.ss = vmcb->save.ss; vmcb12->save.ds = vmcb->save.ds; vmcb12->save.gdtr = vmcb->save.gdtr; vmcb12->save.idtr = vmcb->save.idtr; vmcb12->save.efer = svm->vcpu.arch.efer; vmcb12->save.cr0 = kvm_read_cr0(vcpu); vmcb12->save.cr3 = kvm_read_cr3(vcpu); vmcb12->save.cr2 = vmcb->save.cr2; vmcb12->save.cr4 = svm->vcpu.arch.cr4; vmcb12->save.rflags = kvm_get_rflags(vcpu); vmcb12->save.rip = kvm_rip_read(vcpu); vmcb12->save.rsp = kvm_rsp_read(vcpu); vmcb12->save.rax = kvm_rax_read(vcpu); vmcb12->save.dr7 = vmcb->save.dr7; vmcb12->save.dr6 = svm->vcpu.arch.dr6; vmcb12->save.cpl = vmcb->save.cpl; vmcb12->control.int_state = vmcb->control.int_state; vmcb12->control.exit_code = vmcb->control.exit_code; vmcb12->control.exit_code_hi = vmcb->control.exit_code_hi; vmcb12->control.exit_info_1 = vmcb->control.exit_info_1; vmcb12->control.exit_info_2 = vmcb->control.exit_info_2; if (vmcb12->control.exit_code != SVM_EXIT_ERR) nested_save_pending_event_to_vmcb12(svm, vmcb12); if (svm->nrips_enabled) vmcb12->control.next_rip = vmcb->control.next_rip; vmcb12->control.int_ctl = svm->nested.ctl.int_ctl; vmcb12->control.tlb_ctl = svm->nested.ctl.tlb_ctl; vmcb12->control.event_inj = svm->nested.ctl.event_inj; vmcb12->control.event_inj_err = svm->nested.ctl.event_inj_err; vmcb12->control.pause_filter_count = svm->vmcb->control.pause_filter_count; vmcb12->control.pause_filter_thresh = svm->vmcb->control.pause_filter_thresh; nested_svm_copy_common_state(svm->nested.vmcb02.ptr, svm->vmcb01.ptr); svm_switch_vmcb(svm, &svm->vmcb01); WARN_ON_ONCE(svm->vmcb->control.exit_code != SVM_EXIT_VMRUN); /* * On vmexit the GIF is set to false and * no event can be injected in L1. */ svm_set_gif(svm, false); svm->vmcb->control.exit_int_info = 0; svm->vcpu.arch.tsc_offset = svm->vcpu.arch.l1_tsc_offset; if (svm->vmcb->control.tsc_offset != svm->vcpu.arch.tsc_offset) { svm->vmcb->control.tsc_offset = svm->vcpu.arch.tsc_offset; vmcb_mark_dirty(svm->vmcb, VMCB_INTERCEPTS); } svm->nested.ctl.nested_cr3 = 0; /* * Restore processor state that had been saved in vmcb01 */ kvm_set_rflags(vcpu, svm->vmcb->save.rflags); svm_set_efer(vcpu, svm->vmcb->save.efer); svm_set_cr0(vcpu, svm->vmcb->save.cr0 | X86_CR0_PE); svm_set_cr4(vcpu, svm->vmcb->save.cr4); kvm_rax_write(vcpu, svm->vmcb->save.rax); kvm_rsp_write(vcpu, svm->vmcb->save.rsp); kvm_rip_write(vcpu, svm->vmcb->save.rip); svm->vcpu.arch.dr7 = DR7_FIXED_1; kvm_update_dr7(&svm->vcpu); trace_kvm_nested_vmexit_inject(vmcb12->control.exit_code, vmcb12->control.exit_info_1, vmcb12->control.exit_info_2, vmcb12->control.exit_int_info, vmcb12->control.exit_int_info_err, KVM_ISA_SVM); kvm_vcpu_unmap(vcpu, &map, true); nested_svm_uninit_mmu_context(vcpu); rc = nested_svm_load_cr3(vcpu, svm->vmcb->save.cr3, false); if (rc) return 1; /* * Drop what we picked up for L2 via svm_complete_interrupts() so it * doesn't end up in L1. */ svm->vcpu.arch.nmi_injected = false; kvm_clear_exception_queue(vcpu); kvm_clear_interrupt_queue(vcpu); /* * If we are here following the completion of a VMRUN that * is being single-stepped, queue the pending #DB intercept * right now so that it an be accounted for before we execute * L1's next instruction. */ if (unlikely(svm->vmcb->save.rflags & X86_EFLAGS_TF)) kvm_queue_exception(&(svm->vcpu), DB_VECTOR); return 0; } static void nested_svm_triple_fault(struct kvm_vcpu *vcpu) { nested_svm_simple_vmexit(to_svm(vcpu), SVM_EXIT_SHUTDOWN); } int svm_allocate_nested(struct vcpu_svm *svm) { struct page *vmcb02_page; if (svm->nested.initialized) return 0; vmcb02_page = alloc_page(GFP_KERNEL_ACCOUNT | __GFP_ZERO); if (!vmcb02_page) return -ENOMEM; svm->nested.vmcb02.ptr = page_address(vmcb02_page); svm->nested.vmcb02.pa = __sme_set(page_to_pfn(vmcb02_page) << PAGE_SHIFT); svm->nested.msrpm = svm_vcpu_alloc_msrpm(); if (!svm->nested.msrpm) goto err_free_vmcb02; svm_vcpu_init_msrpm(&svm->vcpu, svm->nested.msrpm); svm->nested.initialized = true; return 0; err_free_vmcb02: __free_page(vmcb02_page); return -ENOMEM; } void svm_free_nested(struct vcpu_svm *svm) { if (!svm->nested.initialized) return; svm_vcpu_free_msrpm(svm->nested.msrpm); svm->nested.msrpm = NULL; __free_page(virt_to_page(svm->nested.vmcb02.ptr)); svm->nested.vmcb02.ptr = NULL; svm->nested.initialized = false; } /* * Forcibly leave nested mode in order to be able to reset the VCPU later on. */ void svm_leave_nested(struct vcpu_svm *svm) { struct kvm_vcpu *vcpu = &svm->vcpu; if (is_guest_mode(vcpu)) { svm->nested.nested_run_pending = 0; leave_guest_mode(vcpu); svm_switch_vmcb(svm, &svm->nested.vmcb02); nested_svm_uninit_mmu_context(vcpu); vmcb_mark_all_dirty(svm->vmcb); } kvm_clear_request(KVM_REQ_GET_NESTED_STATE_PAGES, vcpu); } static int nested_svm_exit_handled_msr(struct vcpu_svm *svm) { u32 offset, msr, value; int write, mask; if (!(vmcb_is_intercept(&svm->nested.ctl, INTERCEPT_MSR_PROT))) return NESTED_EXIT_HOST; msr = svm->vcpu.arch.regs[VCPU_REGS_RCX]; offset = svm_msrpm_offset(msr); write = svm->vmcb->control.exit_info_1 & 1; mask = 1 << ((2 * (msr & 0xf)) + write); if (offset == MSR_INVALID) return NESTED_EXIT_DONE; /* Offset is in 32 bit units but need in 8 bit units */ offset *= 4; if (kvm_vcpu_read_guest(&svm->vcpu, svm->nested.ctl.msrpm_base_pa + offset, &value, 4)) return NESTED_EXIT_DONE; return (value & mask) ? NESTED_EXIT_DONE : NESTED_EXIT_HOST; } static int nested_svm_intercept_ioio(struct vcpu_svm *svm) { unsigned port, size, iopm_len; u16 val, mask; u8 start_bit; u64 gpa; if (!(vmcb_is_intercept(&svm->nested.ctl, INTERCEPT_IOIO_PROT))) return NESTED_EXIT_HOST; port = svm->vmcb->control.exit_info_1 >> 16; size = (svm->vmcb->control.exit_info_1 & SVM_IOIO_SIZE_MASK) >> SVM_IOIO_SIZE_SHIFT; gpa = svm->nested.ctl.iopm_base_pa + (port / 8); start_bit = port % 8; iopm_len = (start_bit + size > 8) ? 2 : 1; mask = (0xf >> (4 - size)) << start_bit; val = 0; if (kvm_vcpu_read_guest(&svm->vcpu, gpa, &val, iopm_len)) return NESTED_EXIT_DONE; return (val & mask) ? NESTED_EXIT_DONE : NESTED_EXIT_HOST; } static int nested_svm_intercept(struct vcpu_svm *svm) { u32 exit_code = svm->vmcb->control.exit_code; int vmexit = NESTED_EXIT_HOST; switch (exit_code) { case SVM_EXIT_MSR: vmexit = nested_svm_exit_handled_msr(svm); break; case SVM_EXIT_IOIO: vmexit = nested_svm_intercept_ioio(svm); break; case SVM_EXIT_READ_CR0 ... SVM_EXIT_WRITE_CR8: { if (vmcb_is_intercept(&svm->nested.ctl, exit_code)) vmexit = NESTED_EXIT_DONE; break; } case SVM_EXIT_READ_DR0 ... SVM_EXIT_WRITE_DR7: { if (vmcb_is_intercept(&svm->nested.ctl, exit_code)) vmexit = NESTED_EXIT_DONE; break; } case SVM_EXIT_EXCP_BASE ... SVM_EXIT_EXCP_BASE + 0x1f: { /* * Host-intercepted exceptions have been checked already in * nested_svm_exit_special. There is nothing to do here, * the vmexit is injected by svm_check_nested_events. */ vmexit = NESTED_EXIT_DONE; break; } case SVM_EXIT_ERR: { vmexit = NESTED_EXIT_DONE; break; } default: { if (vmcb_is_intercept(&svm->nested.ctl, exit_code)) vmexit = NESTED_EXIT_DONE; } } return vmexit; } int nested_svm_exit_handled(struct vcpu_svm *svm) { int vmexit; vmexit = nested_svm_intercept(svm); if (vmexit == NESTED_EXIT_DONE) nested_svm_vmexit(svm); return vmexit; } int nested_svm_check_permissions(struct kvm_vcpu *vcpu) { if (!(vcpu->arch.efer & EFER_SVME) || !is_paging(vcpu)) { kvm_queue_exception(vcpu, UD_VECTOR); return 1; } if (to_svm(vcpu)->vmcb->save.cpl) { kvm_inject_gp(vcpu, 0); return 1; } return 0; } static bool nested_exit_on_exception(struct vcpu_svm *svm) { unsigned int nr = svm->vcpu.arch.exception.nr; return (svm->nested.ctl.intercepts[INTERCEPT_EXCEPTION] & BIT(nr)); } static void nested_svm_inject_exception_vmexit(struct vcpu_svm *svm) { unsigned int nr = svm->vcpu.arch.exception.nr; svm->vmcb->control.exit_code = SVM_EXIT_EXCP_BASE + nr; svm->vmcb->control.exit_code_hi = 0; if (svm->vcpu.arch.exception.has_error_code) svm->vmcb->control.exit_info_1 = svm->vcpu.arch.exception.error_code; /* * EXITINFO2 is undefined for all exception intercepts other * than #PF. */ if (nr == PF_VECTOR) { if (svm->vcpu.arch.exception.nested_apf) svm->vmcb->control.exit_info_2 = svm->vcpu.arch.apf.nested_apf_token; else if (svm->vcpu.arch.exception.has_payload) svm->vmcb->control.exit_info_2 = svm->vcpu.arch.exception.payload; else svm->vmcb->control.exit_info_2 = svm->vcpu.arch.cr2; } else if (nr == DB_VECTOR) { /* See inject_pending_event. */ kvm_deliver_exception_payload(&svm->vcpu); if (svm->vcpu.arch.dr7 & DR7_GD) { svm->vcpu.arch.dr7 &= ~DR7_GD; kvm_update_dr7(&svm->vcpu); } } else WARN_ON(svm->vcpu.arch.exception.has_payload); nested_svm_vmexit(svm); } static inline bool nested_exit_on_init(struct vcpu_svm *svm) { return vmcb_is_intercept(&svm->nested.ctl, INTERCEPT_INIT); } static int svm_check_nested_events(struct kvm_vcpu *vcpu) { struct vcpu_svm *svm = to_svm(vcpu); bool block_nested_events = kvm_event_needs_reinjection(vcpu) || svm->nested.nested_run_pending; struct kvm_lapic *apic = vcpu->arch.apic; if (lapic_in_kernel(vcpu) && test_bit(KVM_APIC_INIT, &apic->pending_events)) { if (block_nested_events) return -EBUSY; if (!nested_exit_on_init(svm)) return 0; nested_svm_simple_vmexit(svm, SVM_EXIT_INIT); return 0; } if (vcpu->arch.exception.pending) { /* * Only a pending nested run can block a pending exception. * Otherwise an injected NMI/interrupt should either be * lost or delivered to the nested hypervisor in the EXITINTINFO * vmcb field, while delivering the pending exception. */ if (svm->nested.nested_run_pending) return -EBUSY; if (!nested_exit_on_exception(svm)) return 0; nested_svm_inject_exception_vmexit(svm); return 0; } if (vcpu->arch.smi_pending && !svm_smi_blocked(vcpu)) { if (block_nested_events) return -EBUSY; if (!nested_exit_on_smi(svm)) return 0; nested_svm_simple_vmexit(svm, SVM_EXIT_SMI); return 0; } if (vcpu->arch.nmi_pending && !svm_nmi_blocked(vcpu)) { if (block_nested_events) return -EBUSY; if (!nested_exit_on_nmi(svm)) return 0; nested_svm_simple_vmexit(svm, SVM_EXIT_NMI); return 0; } if (kvm_cpu_has_interrupt(vcpu) && !svm_interrupt_blocked(vcpu)) { if (block_nested_events) return -EBUSY; if (!nested_exit_on_intr(svm)) return 0; trace_kvm_nested_intr_vmexit(svm->vmcb->save.rip); nested_svm_simple_vmexit(svm, SVM_EXIT_INTR); return 0; } return 0; } int nested_svm_exit_special(struct vcpu_svm *svm) { u32 exit_code = svm->vmcb->control.exit_code; switch (exit_code) { case SVM_EXIT_INTR: case SVM_EXIT_NMI: case SVM_EXIT_NPF: return NESTED_EXIT_HOST; case SVM_EXIT_EXCP_BASE ... SVM_EXIT_EXCP_BASE + 0x1f: { u32 excp_bits = 1 << (exit_code - SVM_EXIT_EXCP_BASE); if (svm->vmcb01.ptr->control.intercepts[INTERCEPT_EXCEPTION] & excp_bits) return NESTED_EXIT_HOST; else if (exit_code == SVM_EXIT_EXCP_BASE + PF_VECTOR && svm->vcpu.arch.apf.host_apf_flags) /* Trap async PF even if not shadowing */ return NESTED_EXIT_HOST; break; } default: break; } return NESTED_EXIT_CONTINUE; } static int svm_get_nested_state(struct kvm_vcpu *vcpu, struct kvm_nested_state __user *user_kvm_nested_state, u32 user_data_size) { struct vcpu_svm *svm; struct kvm_nested_state kvm_state = { .flags = 0, .format = KVM_STATE_NESTED_FORMAT_SVM, .size = sizeof(kvm_state), }; struct vmcb __user *user_vmcb = (struct vmcb __user *) &user_kvm_nested_state->data.svm[0]; if (!vcpu) return kvm_state.size + KVM_STATE_NESTED_SVM_VMCB_SIZE; svm = to_svm(vcpu); if (user_data_size < kvm_state.size) goto out; /* First fill in the header and copy it out. */ if (is_guest_mode(vcpu)) { kvm_state.hdr.svm.vmcb_pa = svm->nested.vmcb12_gpa; kvm_state.size += KVM_STATE_NESTED_SVM_VMCB_SIZE; kvm_state.flags |= KVM_STATE_NESTED_GUEST_MODE; if (svm->nested.nested_run_pending) kvm_state.flags |= KVM_STATE_NESTED_RUN_PENDING; } if (gif_set(svm)) kvm_state.flags |= KVM_STATE_NESTED_GIF_SET; if (copy_to_user(user_kvm_nested_state, &kvm_state, sizeof(kvm_state))) return -EFAULT; if (!is_guest_mode(vcpu)) goto out; /* * Copy over the full size of the VMCB rather than just the size * of the structs. */ if (clear_user(user_vmcb, KVM_STATE_NESTED_SVM_VMCB_SIZE)) return -EFAULT; if (copy_to_user(&user_vmcb->control, &svm->nested.ctl, sizeof(user_vmcb->control))) return -EFAULT; if (copy_to_user(&user_vmcb->save, &svm->vmcb01.ptr->save, sizeof(user_vmcb->save))) return -EFAULT; out: return kvm_state.size; } static int svm_set_nested_state(struct kvm_vcpu *vcpu, struct kvm_nested_state __user *user_kvm_nested_state, struct kvm_nested_state *kvm_state) { struct vcpu_svm *svm = to_svm(vcpu); struct vmcb __user *user_vmcb = (struct vmcb __user *) &user_kvm_nested_state->data.svm[0]; struct vmcb_control_area *ctl; struct vmcb_save_area *save; int ret; u32 cr0; BUILD_BUG_ON(sizeof(struct vmcb_control_area) + sizeof(struct vmcb_save_area) > KVM_STATE_NESTED_SVM_VMCB_SIZE); if (kvm_state->format != KVM_STATE_NESTED_FORMAT_SVM) return -EINVAL; if (kvm_state->flags & ~(KVM_STATE_NESTED_GUEST_MODE | KVM_STATE_NESTED_RUN_PENDING | KVM_STATE_NESTED_GIF_SET)) return -EINVAL; /* * If in guest mode, vcpu->arch.efer actually refers to the L2 guest's * EFER.SVME, but EFER.SVME still has to be 1 for VMRUN to succeed. */ if (!(vcpu->arch.efer & EFER_SVME)) { /* GIF=1 and no guest mode are required if SVME=0. */ if (kvm_state->flags != KVM_STATE_NESTED_GIF_SET) return -EINVAL; } /* SMM temporarily disables SVM, so we cannot be in guest mode. */ if (is_smm(vcpu) && (kvm_state->flags & KVM_STATE_NESTED_GUEST_MODE)) return -EINVAL; if (!(kvm_state->flags & KVM_STATE_NESTED_GUEST_MODE)) { svm_leave_nested(svm); svm_set_gif(svm, !!(kvm_state->flags & KVM_STATE_NESTED_GIF_SET)); return 0; } if (!page_address_valid(vcpu, kvm_state->hdr.svm.vmcb_pa)) return -EINVAL; if (kvm_state->size < sizeof(*kvm_state) + KVM_STATE_NESTED_SVM_VMCB_SIZE) return -EINVAL; ret = -ENOMEM; ctl = kzalloc(sizeof(*ctl), GFP_KERNEL_ACCOUNT); save = kzalloc(sizeof(*save), GFP_KERNEL_ACCOUNT); if (!ctl || !save) goto out_free; ret = -EFAULT; if (copy_from_user(ctl, &user_vmcb->control, sizeof(*ctl))) goto out_free; if (copy_from_user(save, &user_vmcb->save, sizeof(*save))) goto out_free; ret = -EINVAL; if (!nested_vmcb_check_controls(vcpu, ctl)) goto out_free; /* * Processor state contains L2 state. Check that it is * valid for guest mode (see nested_vmcb_check_save). */ cr0 = kvm_read_cr0(vcpu); if (((cr0 & X86_CR0_CD) == 0) && (cr0 & X86_CR0_NW)) goto out_free; /* * Validate host state saved from before VMRUN (see * nested_svm_check_permissions). */ if (!(save->cr0 & X86_CR0_PG) || !(save->cr0 & X86_CR0_PE) || (save->rflags & X86_EFLAGS_VM) || !nested_vmcb_valid_sregs(vcpu, save)) goto out_free; /* * All checks done, we can enter guest mode. Userspace provides * vmcb12.control, which will be combined with L1 and stored into * vmcb02, and the L1 save state which we store in vmcb01. * L2 registers if needed are moved from the current VMCB to VMCB02. */ svm->nested.nested_run_pending = !!(kvm_state->flags & KVM_STATE_NESTED_RUN_PENDING); svm->nested.vmcb12_gpa = kvm_state->hdr.svm.vmcb_pa; if (svm->current_vmcb == &svm->vmcb01) svm->nested.vmcb02.ptr->save = svm->vmcb01.ptr->save; svm->vmcb01.ptr->save.es = save->es; svm->vmcb01.ptr->save.cs = save->cs; svm->vmcb01.ptr->save.ss = save->ss; svm->vmcb01.ptr->save.ds = save->ds; svm->vmcb01.ptr->save.gdtr = save->gdtr; svm->vmcb01.ptr->save.idtr = save->idtr; svm->vmcb01.ptr->save.rflags = save->rflags | X86_EFLAGS_FIXED; svm->vmcb01.ptr->save.efer = save->efer; svm->vmcb01.ptr->save.cr0 = save->cr0; svm->vmcb01.ptr->save.cr3 = save->cr3; svm->vmcb01.ptr->save.cr4 = save->cr4; svm->vmcb01.ptr->save.rax = save->rax; svm->vmcb01.ptr->save.rsp = save->rsp; svm->vmcb01.ptr->save.rip = save->rip; svm->vmcb01.ptr->save.cpl = 0; nested_load_control_from_vmcb12(svm, ctl); svm_switch_vmcb(svm, &svm->nested.vmcb02); nested_vmcb02_prepare_control(svm); kvm_make_request(KVM_REQ_GET_NESTED_STATE_PAGES, vcpu); ret = 0; out_free: kfree(save); kfree(ctl); return ret; } static bool svm_get_nested_state_pages(struct kvm_vcpu *vcpu) { struct vcpu_svm *svm = to_svm(vcpu); if (WARN_ON(!is_guest_mode(vcpu))) return true; if (nested_svm_load_cr3(&svm->vcpu, vcpu->arch.cr3, nested_npt_enabled(svm))) return false; if (!nested_svm_vmrun_msrpm(svm)) { vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR; vcpu->run->internal.suberror = KVM_INTERNAL_ERROR_EMULATION; vcpu->run->internal.ndata = 0; return false; } return true; } struct kvm_x86_nested_ops svm_nested_ops = { .check_events = svm_check_nested_events, .triple_fault = nested_svm_triple_fault, .get_nested_state_pages = svm_get_nested_state_pages, .get_state = svm_get_nested_state, .set_state = svm_set_nested_state, };