diff options
Diffstat (limited to 'arch/x86/kvm/svm/nested.c')
-rw-r--r-- | arch/x86/kvm/svm/nested.c | 1265 |
1 files changed, 1265 insertions, 0 deletions
diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c new file mode 100644 index 000000000..e7feaa791 --- /dev/null +++ b/arch/x86/kvm/svm/nested.c @@ -0,0 +1,1265 @@ +// 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 <yaniv@qumranet.com> + * Avi Kivity <avi@qumranet.com> + */ + +#define pr_fmt(fmt) "SVM: " fmt + +#include <linux/kvm_types.h> +#include <linux/kvm_host.h> +#include <linux/kernel.h> + +#include <asm/msr-index.h> +#include <asm/debugreg.h> + +#include "kvm_emulate.h" +#include "trace.h" +#include "mmu.h" +#include "x86.h" +#include "cpuid.h" +#include "lapic.h" +#include "svm.h" + +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); + struct vmcb *hsave = svm->nested.hsave; + + WARN_ON(mmu_is_nested(vcpu)); + + vcpu->arch.mmu = &vcpu->arch.guest_mmu; + kvm_init_shadow_npt_mmu(vcpu, X86_CR0_PG, hsave->save.cr4, hsave->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->nested.hsave->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]; + + vmcb_set_intercept(c, INTERCEPT_VMLOAD); + vmcb_set_intercept(c, INTERCEPT_VMSAVE); +} + +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; +} + +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_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; +} + +static bool nested_vmcb_check_controls(struct vmcb_control_area *control) +{ + if ((vmcb_is_intercept(control, INTERCEPT_VMRUN)) == 0) + return false; + + if (control->asid == 0) + return false; + + if ((control->nested_ctl & SVM_NESTED_CTL_NP_ENABLE) && + !npt_enabled) + return false; + + return true; +} + +static bool nested_vmcb_check_save(struct vcpu_svm *svm, struct vmcb *vmcb12) +{ + struct kvm_vcpu *vcpu = &svm->vcpu; + bool vmcb12_lma; + + /* + * 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 ((vmcb12->save.efer & EFER_SVME) == 0) + return false; + + if (((vmcb12->save.cr0 & X86_CR0_CD) == 0) && (vmcb12->save.cr0 & X86_CR0_NW)) + return false; + + if (!kvm_dr6_valid(vmcb12->save.dr6) || !kvm_dr7_valid(vmcb12->save.dr7)) + return false; + + vmcb12_lma = (vmcb12->save.efer & EFER_LME) && (vmcb12->save.cr0 & X86_CR0_PG); + + if (vmcb12_lma) { + if (!(vmcb12->save.cr4 & X86_CR4_PAE) || + !(vmcb12->save.cr0 & X86_CR0_PE) || + (vmcb12->save.cr3 & vcpu->arch.cr3_lm_rsvd_bits)) + return false; + } + if (kvm_valid_cr4(&svm->vcpu, vmcb12->save.cr4)) + return false; + + return true; +} + +static void load_nested_vmcb_control(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 nested_vmcb. + */ +void sync_nested_vmcb_control(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_vmcb_save_pending_event(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 (cr3 & rsvd_bits(cpuid_maxphyaddr(vcpu), 63)) + return -EINVAL; + + if (!nested_npt && is_pae_paging(vcpu) && + (cr3 != kvm_read_cr3(vcpu) || pdptrs_changed(vcpu))) { + if (!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; +} + +static void nested_prepare_vmcb_save(struct vcpu_svm *svm, struct vmcb *vmcb12) +{ + /* Load the nested guest state */ + 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.gdtr = vmcb12->save.gdtr; + svm->vmcb->save.idtr = vmcb12->save.idtr; + kvm_set_rflags(&svm->vcpu, vmcb12->save.rflags); + + /* + * 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->vmcb->save.cr2 = 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; + svm->vmcb->save.dr7 = vmcb12->save.dr7; + svm->vcpu.arch.dr6 = vmcb12->save.dr6; + svm->vmcb->save.cpl = vmcb12->save.cpl; +} + +static void nested_prepare_vmcb_control(struct vcpu_svm *svm) +{ + const u32 int_ctl_vmcb01_bits = + V_INTR_MASKING_MASK | V_GIF_MASK | V_GIF_ENABLE_MASK; + + const u32 int_ctl_vmcb12_bits = V_TPR_MASK | V_IRQ_INJECTION_BITS_MASK; + + 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 & int_ctl_vmcb12_bits) | + (svm->nested.hsave->control.int_ctl & int_ctl_vmcb01_bits); + + 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 affect here + */ + recalc_intercepts(svm); + + vmcb_mark_all_dirty(svm->vmcb); +} + +int enter_svm_guest_mode(struct vcpu_svm *svm, u64 vmcb12_gpa, + struct vmcb *vmcb12) +{ + int ret; + + svm->nested.vmcb12_gpa = vmcb12_gpa; + nested_prepare_vmcb_save(svm, vmcb12); + nested_prepare_vmcb_control(svm); + + ret = nested_svm_load_cr3(&svm->vcpu, vmcb12->save.cr3, + nested_npt_enabled(svm)); + if (ret) + return ret; + + if (!npt_enabled) + svm->vcpu.arch.mmu->inject_page_fault = svm_inject_page_fault_nested; + + svm_set_gif(svm, true); + + return 0; +} + +int nested_svm_vmrun(struct vcpu_svm *svm) +{ + int ret; + struct vmcb *vmcb12; + struct vmcb *hsave = svm->nested.hsave; + struct vmcb *vmcb = svm->vmcb; + struct kvm_host_map map; + u64 vmcb12_gpa; + + if (is_smm(&svm->vcpu)) { + kvm_queue_exception(&svm->vcpu, UD_VECTOR); + return 1; + } + + vmcb12_gpa = svm->vmcb->save.rax; + ret = kvm_vcpu_map(&svm->vcpu, gpa_to_gfn(vmcb12_gpa), &map); + if (ret == -EINVAL) { + kvm_inject_gp(&svm->vcpu, 0); + return 1; + } else if (ret) { + return kvm_skip_emulated_instruction(&svm->vcpu); + } + + ret = kvm_skip_emulated_instruction(&svm->vcpu); + + vmcb12 = map.hva; + + if (WARN_ON_ONCE(!svm->nested.initialized)) + return -EINVAL; + + load_nested_vmcb_control(svm, &vmcb12->control); + + if (!nested_vmcb_check_save(svm, vmcb12) || + !nested_vmcb_check_controls(&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; + } + + 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]); + + /* Clear internal status */ + kvm_clear_exception_queue(&svm->vcpu); + kvm_clear_interrupt_queue(&svm->vcpu); + + /* + * Save the old vmcb, so we don't need to pick what we save, but can + * restore everything when a VMEXIT occurs + */ + hsave->save.es = vmcb->save.es; + hsave->save.cs = vmcb->save.cs; + hsave->save.ss = vmcb->save.ss; + hsave->save.ds = vmcb->save.ds; + hsave->save.gdtr = vmcb->save.gdtr; + hsave->save.idtr = vmcb->save.idtr; + hsave->save.efer = svm->vcpu.arch.efer; + hsave->save.cr0 = kvm_read_cr0(&svm->vcpu); + hsave->save.cr4 = svm->vcpu.arch.cr4; + hsave->save.rflags = kvm_get_rflags(&svm->vcpu); + hsave->save.rip = kvm_rip_read(&svm->vcpu); + hsave->save.rsp = vmcb->save.rsp; + hsave->save.rax = vmcb->save.rax; + if (npt_enabled) + hsave->save.cr3 = vmcb->save.cr3; + else + hsave->save.cr3 = kvm_read_cr3(&svm->vcpu); + + copy_vmcb_control_area(&hsave->control, &vmcb->control); + + svm->nested.nested_run_pending = 1; + + if (enter_svm_guest_mode(svm, 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(&svm->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) +{ + int rc; + struct vmcb *vmcb12; + struct vmcb *hsave = svm->nested.hsave; + struct vmcb *vmcb = svm->vmcb; + struct kvm_host_map map; + + rc = kvm_vcpu_map(&svm->vcpu, gpa_to_gfn(svm->nested.vmcb12_gpa), &map); + if (rc) { + if (rc == -EINVAL) + kvm_inject_gp(&svm->vcpu, 0); + return 1; + } + + vmcb12 = map.hva; + + /* Exit Guest-Mode */ + leave_guest_mode(&svm->vcpu); + svm->nested.vmcb12_gpa = 0; + WARN_ON_ONCE(svm->nested.nested_run_pending); + + kvm_clear_request(KVM_REQ_GET_NESTED_STATE_PAGES, &svm->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(&svm->vcpu); + vmcb12->save.cr3 = kvm_read_cr3(&svm->vcpu); + vmcb12->save.cr2 = vmcb->save.cr2; + vmcb12->save.cr4 = svm->vcpu.arch.cr4; + vmcb12->save.rflags = kvm_get_rflags(&svm->vcpu); + vmcb12->save.rip = kvm_rip_read(&svm->vcpu); + vmcb12->save.rsp = kvm_rsp_read(&svm->vcpu); + vmcb12->save.rax = kvm_rax_read(&svm->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_vmcb_save_pending_event(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; + + /* Restore the original control entries */ + copy_vmcb_control_area(&vmcb->control, &hsave->control); + + /* On vmexit the GIF is set to false */ + svm_set_gif(svm, false); + + svm->vmcb->control.tsc_offset = svm->vcpu.arch.tsc_offset = + svm->vcpu.arch.l1_tsc_offset; + + svm->nested.ctl.nested_cr3 = 0; + + /* Restore selected save entries */ + svm->vmcb->save.es = hsave->save.es; + svm->vmcb->save.cs = hsave->save.cs; + svm->vmcb->save.ss = hsave->save.ss; + svm->vmcb->save.ds = hsave->save.ds; + svm->vmcb->save.gdtr = hsave->save.gdtr; + svm->vmcb->save.idtr = hsave->save.idtr; + kvm_set_rflags(&svm->vcpu, hsave->save.rflags); + svm_set_efer(&svm->vcpu, hsave->save.efer); + svm_set_cr0(&svm->vcpu, hsave->save.cr0 | X86_CR0_PE); + svm_set_cr4(&svm->vcpu, hsave->save.cr4); + kvm_rax_write(&svm->vcpu, hsave->save.rax); + kvm_rsp_write(&svm->vcpu, hsave->save.rsp); + kvm_rip_write(&svm->vcpu, hsave->save.rip); + svm->vmcb->save.dr7 = 0; + svm->vmcb->save.cpl = 0; + svm->vmcb->control.exit_int_info = 0; + + vmcb_mark_all_dirty(svm->vmcb); + + 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(&svm->vcpu, &map, true); + + nested_svm_uninit_mmu_context(&svm->vcpu); + + rc = nested_svm_load_cr3(&svm->vcpu, hsave->save.cr3, false); + if (rc) + return 1; + + if (npt_enabled) + svm->vmcb->save.cr3 = hsave->save.cr3; + + /* + * 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(&svm->vcpu); + kvm_clear_interrupt_queue(&svm->vcpu); + + return 0; +} + +int svm_allocate_nested(struct vcpu_svm *svm) +{ + struct page *hsave_page; + + if (svm->nested.initialized) + return 0; + + hsave_page = alloc_page(GFP_KERNEL_ACCOUNT | __GFP_ZERO); + if (!hsave_page) + return -ENOMEM; + svm->nested.hsave = page_address(hsave_page); + + svm->nested.msrpm = svm_vcpu_alloc_msrpm(); + if (!svm->nested.msrpm) + goto err_free_hsave; + svm_vcpu_init_msrpm(&svm->vcpu, svm->nested.msrpm); + + svm->nested.initialized = true; + return 0; + +err_free_hsave: + __free_page(hsave_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.hsave)); + svm->nested.hsave = 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 kvm_vcpu *vcpu) +{ + struct vcpu_svm *svm = to_svm(vcpu); + + if (is_guest_mode(&svm->vcpu)) { + struct vmcb *hsave = svm->nested.hsave; + struct vmcb *vmcb = svm->vmcb; + + svm->nested.nested_run_pending = 0; + leave_guest_mode(&svm->vcpu); + copy_vmcb_control_area(&vmcb->control, &hsave->control); + nested_svm_uninit_mmu_context(&svm->vcpu); + } + + kvm_clear_request(KVM_REQ_GET_NESTED_STATE_PAGES, &svm->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 vcpu_svm *svm) +{ + if (!(svm->vcpu.arch.efer & EFER_SVME) || + !is_paging(&svm->vcpu)) { + kvm_queue_exception(&svm->vcpu, UD_VECTOR); + return 1; + } + + if (svm->vmcb->save.cpl) { + kvm_inject_gp(&svm->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 void nested_svm_smi(struct vcpu_svm *svm) +{ + svm->vmcb->control.exit_code = SVM_EXIT_SMI; + svm->vmcb->control.exit_info_1 = 0; + svm->vmcb->control.exit_info_2 = 0; + + nested_svm_vmexit(svm); +} + +static void nested_svm_nmi(struct vcpu_svm *svm) +{ + svm->vmcb->control.exit_code = SVM_EXIT_NMI; + svm->vmcb->control.exit_info_1 = 0; + svm->vmcb->control.exit_info_2 = 0; + + nested_svm_vmexit(svm); +} + +static void nested_svm_intr(struct vcpu_svm *svm) +{ + trace_kvm_nested_intr_vmexit(svm->vmcb->save.rip); + + svm->vmcb->control.exit_code = SVM_EXIT_INTR; + svm->vmcb->control.exit_info_1 = 0; + svm->vmcb->control.exit_info_2 = 0; + + 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 void nested_svm_init(struct vcpu_svm *svm) +{ + svm->vmcb->control.exit_code = SVM_EXIT_INIT; + svm->vmcb->control.exit_info_1 = 0; + svm->vmcb->control.exit_info_2 = 0; + + nested_svm_vmexit(svm); +} + + +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_init(svm); + return 0; + } + + if (vcpu->arch.exception.pending) { + if (block_nested_events) + 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_smi(svm); + 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_nmi(svm); + 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; + nested_svm_intr(svm); + 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 (get_host_vmcb(svm)->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->nested.hsave->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 *hsave = svm->nested.hsave; + 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(vcpu); + 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(ctl)) + goto out_free; + + /* + * Processor state contains L2 state. Check that it is + * valid for guest mode (see nested_vmcb_checks). + */ + 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). + * TODO: validate reserved bits for all saved state. + */ + if (!(save->cr0 & X86_CR0_PG)) + goto out_free; + if (!(save->efer & EFER_SVME)) + goto out_free; + + /* + * All checks done, we can enter guest mode. L1 control fields + * come from the nested save state. Guest state is already + * in the registers, the save area of the nested state instead + * contains saved L1 state. + */ + copy_vmcb_control_area(&hsave->control, &svm->vmcb->control); + hsave->save = *save; + + if (is_guest_mode(vcpu)) + svm_leave_nested(vcpu); + + svm->nested.vmcb12_gpa = kvm_state->hdr.svm.vmcb_pa; + load_nested_vmcb_control(svm, ctl); + nested_prepare_vmcb_control(svm); + + kvm_make_request(KVM_REQ_GET_NESTED_STATE_PAGES, vcpu); + ret = 0; +out_free: + kfree(save); + kfree(ctl); + + return ret; +} + +struct kvm_x86_nested_ops svm_nested_ops = { + .leave_nested = svm_leave_nested, + .check_events = svm_check_nested_events, + .get_nested_state_pages = svm_get_nested_state_pages, + .get_state = svm_get_nested_state, + .set_state = svm_set_nested_state, +}; |