diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2020-04-08 10:56:50 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2020-04-08 10:56:50 -0700 |
commit | 0339eb95403fb4664219be344a9399a3fdf1fae1 (patch) | |
tree | 76a6cb0d0cfcf8712867bf7c34cef078245f790b /arch/x86/kvm/svm/nested.c | |
parent | 9bb715260ed4cef6948cb2e05cf670462367da71 (diff) | |
parent | dbef2808af6c594922fe32833b30f55f35e9da6d (diff) |
Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull more kvm updates from Paolo Bonzini:
"s390:
- nested virtualization fixes
x86:
- split svm.c
- miscellaneous fixes"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: VMX: fix crash cleanup when KVM wasn't used
KVM: X86: Filter out the broadcast dest for IPI fastpath
KVM: s390: vsie: Fix possible race when shadowing region 3 tables
KVM: s390: vsie: Fix delivery of addressing exceptions
KVM: s390: vsie: Fix region 1 ASCE sanity shadow address checks
KVM: nVMX: don't clear mtf_pending when nested events are blocked
KVM: VMX: Remove unnecessary exception trampoline in vmx_vmenter
KVM: SVM: Split svm_vcpu_run inline assembly to separate file
KVM: SVM: Move SEV code to separate file
KVM: SVM: Move AVIC code to separate file
KVM: SVM: Move Nested SVM Implementation to nested.c
kVM SVM: Move SVM related files to own sub-directory
Diffstat (limited to 'arch/x86/kvm/svm/nested.c')
-rw-r--r-- | arch/x86/kvm/svm/nested.c | 823 |
1 files changed, 823 insertions, 0 deletions
diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c new file mode 100644 index 000000000000..90a1ca939627 --- /dev/null +++ b/arch/x86/kvm/svm/nested.c @@ -0,0 +1,823 @@ +// 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 "kvm_emulate.h" +#include "trace.h" +#include "mmu.h" +#include "x86.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; + + /* + * The present bit is always zero for page structure faults on real + * hardware. + */ + if (svm->vmcb->control.exit_info_1 & (2ULL << 32)) + svm->vmcb->control.exit_info_1 &= ~1; + + nested_svm_vmexit(svm); +} + +static u64 nested_svm_get_tdp_pdptr(struct kvm_vcpu *vcpu, int index) +{ + struct vcpu_svm *svm = to_svm(vcpu); + u64 cr3 = svm->nested.nested_cr3; + u64 pdpte; + int ret; + + ret = kvm_vcpu_read_guest_page(vcpu, gpa_to_gfn(__sme_clr(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.nested_cr3; +} + +static void nested_svm_init_mmu_context(struct kvm_vcpu *vcpu) +{ + WARN_ON(mmu_is_nested(vcpu)); + + vcpu->arch.mmu = &vcpu->arch.guest_mmu; + kvm_init_shadow_mmu(vcpu); + 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; + vcpu->arch.mmu->shadow_root_level = kvm_x86_ops.get_tdp_level(vcpu); + 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; + struct nested_state *g; + + 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; + + c->intercept_cr = h->intercept_cr; + c->intercept_dr = h->intercept_dr; + c->intercept_exceptions = h->intercept_exceptions; + c->intercept = h->intercept; + + if (svm->vcpu.arch.hflags & HF_VINTR_MASK) { + /* We only want the cr8 intercept bits of L1 */ + c->intercept_cr &= ~(1U << INTERCEPT_CR8_READ); + c->intercept_cr &= ~(1U << 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. + */ + c->intercept &= ~(1ULL << INTERCEPT_VINTR); + } + + /* We don't want to see VMMCALLs from a nested guest */ + c->intercept &= ~(1ULL << INTERCEPT_VMMCALL); + + c->intercept_cr |= g->intercept_cr; + c->intercept_dr |= g->intercept_dr; + c->intercept_exceptions |= g->intercept_exceptions; + c->intercept |= g->intercept; +} + +static void copy_vmcb_control_area(struct vmcb *dst_vmcb, struct vmcb *from_vmcb) +{ + struct vmcb_control_area *dst = &dst_vmcb->control; + struct vmcb_control_area *from = &from_vmcb->control; + + dst->intercept_cr = from->intercept_cr; + dst->intercept_dr = from->intercept_dr; + dst->intercept_exceptions = from->intercept_exceptions; + dst->intercept = from->intercept; + dst->iopm_base_pa = from->iopm_base_pa; + dst->msrpm_base_pa = from->msrpm_base_pa; + dst->tsc_offset = from->tsc_offset; + dst->asid = from->asid; + 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 (!(svm->nested.intercept & (1ULL << 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.vmcb_msrpm + (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 nested_vmcb_checks(struct vmcb *vmcb) +{ + if ((vmcb->save.efer & EFER_SVME) == 0) + return false; + + if ((vmcb->control.intercept & (1ULL << INTERCEPT_VMRUN)) == 0) + return false; + + if (vmcb->control.asid == 0) + return false; + + if ((vmcb->control.nested_ctl & SVM_NESTED_CTL_NP_ENABLE) && + !npt_enabled) + return false; + + return true; +} + +void enter_svm_guest_mode(struct vcpu_svm *svm, u64 vmcb_gpa, + struct vmcb *nested_vmcb, struct kvm_host_map *map) +{ + bool evaluate_pending_interrupts = + is_intercept(svm, INTERCEPT_VINTR) || + is_intercept(svm, INTERCEPT_IRET); + + if (kvm_get_rflags(&svm->vcpu) & X86_EFLAGS_IF) + svm->vcpu.arch.hflags |= HF_HIF_MASK; + else + svm->vcpu.arch.hflags &= ~HF_HIF_MASK; + + if (nested_vmcb->control.nested_ctl & SVM_NESTED_CTL_NP_ENABLE) { + svm->nested.nested_cr3 = nested_vmcb->control.nested_cr3; + nested_svm_init_mmu_context(&svm->vcpu); + } + + /* Load the nested guest state */ + svm->vmcb->save.es = nested_vmcb->save.es; + svm->vmcb->save.cs = nested_vmcb->save.cs; + svm->vmcb->save.ss = nested_vmcb->save.ss; + svm->vmcb->save.ds = nested_vmcb->save.ds; + svm->vmcb->save.gdtr = nested_vmcb->save.gdtr; + svm->vmcb->save.idtr = nested_vmcb->save.idtr; + kvm_set_rflags(&svm->vcpu, nested_vmcb->save.rflags); + svm_set_efer(&svm->vcpu, nested_vmcb->save.efer); + svm_set_cr0(&svm->vcpu, nested_vmcb->save.cr0); + svm_set_cr4(&svm->vcpu, nested_vmcb->save.cr4); + if (npt_enabled) { + svm->vmcb->save.cr3 = nested_vmcb->save.cr3; + svm->vcpu.arch.cr3 = nested_vmcb->save.cr3; + } else + (void)kvm_set_cr3(&svm->vcpu, nested_vmcb->save.cr3); + + /* Guest paging mode is active - reset mmu */ + kvm_mmu_reset_context(&svm->vcpu); + + svm->vmcb->save.cr2 = svm->vcpu.arch.cr2 = nested_vmcb->save.cr2; + kvm_rax_write(&svm->vcpu, nested_vmcb->save.rax); + kvm_rsp_write(&svm->vcpu, nested_vmcb->save.rsp); + kvm_rip_write(&svm->vcpu, nested_vmcb->save.rip); + + /* In case we don't even reach vcpu_run, the fields are not updated */ + svm->vmcb->save.rax = nested_vmcb->save.rax; + svm->vmcb->save.rsp = nested_vmcb->save.rsp; + svm->vmcb->save.rip = nested_vmcb->save.rip; + svm->vmcb->save.dr7 = nested_vmcb->save.dr7; + svm->vmcb->save.dr6 = nested_vmcb->save.dr6; + svm->vmcb->save.cpl = nested_vmcb->save.cpl; + + svm->nested.vmcb_msrpm = nested_vmcb->control.msrpm_base_pa & ~0x0fffULL; + svm->nested.vmcb_iopm = nested_vmcb->control.iopm_base_pa & ~0x0fffULL; + + /* cache intercepts */ + svm->nested.intercept_cr = nested_vmcb->control.intercept_cr; + svm->nested.intercept_dr = nested_vmcb->control.intercept_dr; + svm->nested.intercept_exceptions = nested_vmcb->control.intercept_exceptions; + svm->nested.intercept = nested_vmcb->control.intercept; + + svm_flush_tlb(&svm->vcpu, true); + svm->vmcb->control.int_ctl = nested_vmcb->control.int_ctl | V_INTR_MASKING_MASK; + if (nested_vmcb->control.int_ctl & V_INTR_MASKING_MASK) + svm->vcpu.arch.hflags |= HF_VINTR_MASK; + else + svm->vcpu.arch.hflags &= ~HF_VINTR_MASK; + + svm->vcpu.arch.tsc_offset += nested_vmcb->control.tsc_offset; + svm->vmcb->control.tsc_offset = svm->vcpu.arch.tsc_offset; + + svm->vmcb->control.virt_ext = nested_vmcb->control.virt_ext; + svm->vmcb->control.int_vector = nested_vmcb->control.int_vector; + svm->vmcb->control.int_state = nested_vmcb->control.int_state; + svm->vmcb->control.event_inj = nested_vmcb->control.event_inj; + svm->vmcb->control.event_inj_err = nested_vmcb->control.event_inj_err; + + svm->vmcb->control.pause_filter_count = + nested_vmcb->control.pause_filter_count; + svm->vmcb->control.pause_filter_thresh = + nested_vmcb->control.pause_filter_thresh; + + kvm_vcpu_unmap(&svm->vcpu, map, true); + + /* 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); + + svm->nested.vmcb = vmcb_gpa; + + /* + * If L1 had a pending IRQ/NMI before executing VMRUN, + * which wasn't delivered because it was disallowed (e.g. + * interrupts disabled), L0 needs to evaluate if this pending + * event should cause an exit from L2 to L1 or be delivered + * directly to L2. + * + * Usually this would be handled by the processor noticing an + * IRQ/NMI window request. However, VMRUN can unblock interrupts + * by implicitly setting GIF, so force L0 to perform pending event + * evaluation by requesting a KVM_REQ_EVENT. + */ + enable_gif(svm); + if (unlikely(evaluate_pending_interrupts)) + kvm_make_request(KVM_REQ_EVENT, &svm->vcpu); + + mark_all_dirty(svm->vmcb); +} + +int nested_svm_vmrun(struct vcpu_svm *svm) +{ + int ret; + struct vmcb *nested_vmcb; + struct vmcb *hsave = svm->nested.hsave; + struct vmcb *vmcb = svm->vmcb; + struct kvm_host_map map; + u64 vmcb_gpa; + + vmcb_gpa = svm->vmcb->save.rax; + + ret = kvm_vcpu_map(&svm->vcpu, gpa_to_gfn(vmcb_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); + + nested_vmcb = map.hva; + + if (!nested_vmcb_checks(nested_vmcb)) { + nested_vmcb->control.exit_code = SVM_EXIT_ERR; + nested_vmcb->control.exit_code_hi = 0; + nested_vmcb->control.exit_info_1 = 0; + nested_vmcb->control.exit_info_2 = 0; + + kvm_vcpu_unmap(&svm->vcpu, &map, true); + + return ret; + } + + trace_kvm_nested_vmrun(svm->vmcb->save.rip, vmcb_gpa, + nested_vmcb->save.rip, + nested_vmcb->control.int_ctl, + nested_vmcb->control.event_inj, + nested_vmcb->control.nested_ctl); + + trace_kvm_nested_intercepts(nested_vmcb->control.intercept_cr & 0xffff, + nested_vmcb->control.intercept_cr >> 16, + nested_vmcb->control.intercept_exceptions, + nested_vmcb->control.intercept); + + /* 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, vmcb); + + enter_svm_guest_mode(svm, vmcb_gpa, nested_vmcb, &map); + + if (!nested_svm_vmrun_msrpm(svm)) { + 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); + } + + 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 *nested_vmcb; + struct vmcb *hsave = svm->nested.hsave; + struct vmcb *vmcb = svm->vmcb; + struct kvm_host_map map; + + trace_kvm_nested_vmexit_inject(vmcb->control.exit_code, + vmcb->control.exit_info_1, + vmcb->control.exit_info_2, + vmcb->control.exit_int_info, + vmcb->control.exit_int_info_err, + KVM_ISA_SVM); + + rc = kvm_vcpu_map(&svm->vcpu, gpa_to_gfn(svm->nested.vmcb), &map); + if (rc) { + if (rc == -EINVAL) + kvm_inject_gp(&svm->vcpu, 0); + return 1; + } + + nested_vmcb = map.hva; + + /* Exit Guest-Mode */ + leave_guest_mode(&svm->vcpu); + svm->nested.vmcb = 0; + + /* Give the current vmcb to the guest */ + disable_gif(svm); + + nested_vmcb->save.es = vmcb->save.es; + nested_vmcb->save.cs = vmcb->save.cs; + nested_vmcb->save.ss = vmcb->save.ss; + nested_vmcb->save.ds = vmcb->save.ds; + nested_vmcb->save.gdtr = vmcb->save.gdtr; + nested_vmcb->save.idtr = vmcb->save.idtr; + nested_vmcb->save.efer = svm->vcpu.arch.efer; + nested_vmcb->save.cr0 = kvm_read_cr0(&svm->vcpu); + nested_vmcb->save.cr3 = kvm_read_cr3(&svm->vcpu); + nested_vmcb->save.cr2 = vmcb->save.cr2; + nested_vmcb->save.cr4 = svm->vcpu.arch.cr4; + nested_vmcb->save.rflags = kvm_get_rflags(&svm->vcpu); + nested_vmcb->save.rip = vmcb->save.rip; + nested_vmcb->save.rsp = vmcb->save.rsp; + nested_vmcb->save.rax = vmcb->save.rax; + nested_vmcb->save.dr7 = vmcb->save.dr7; + nested_vmcb->save.dr6 = vmcb->save.dr6; + nested_vmcb->save.cpl = vmcb->save.cpl; + + nested_vmcb->control.int_ctl = vmcb->control.int_ctl; + nested_vmcb->control.int_vector = vmcb->control.int_vector; + nested_vmcb->control.int_state = vmcb->control.int_state; + nested_vmcb->control.exit_code = vmcb->control.exit_code; + nested_vmcb->control.exit_code_hi = vmcb->control.exit_code_hi; + nested_vmcb->control.exit_info_1 = vmcb->control.exit_info_1; + nested_vmcb->control.exit_info_2 = vmcb->control.exit_info_2; + nested_vmcb->control.exit_int_info = vmcb->control.exit_int_info; + nested_vmcb->control.exit_int_info_err = vmcb->control.exit_int_info_err; + + if (svm->nrips_enabled) + nested_vmcb->control.next_rip = vmcb->control.next_rip; + + /* + * If we emulate a VMRUN/#VMEXIT in the same host #vmexit cycle we have + * to make sure that we do not lose injected events. So check event_inj + * here and copy it to exit_int_info if it is valid. + * Exit_int_info and event_inj can't be both valid because the case + * below only happens on a VMRUN instruction intercept which has + * no valid exit_int_info set. + */ + if (vmcb->control.event_inj & SVM_EVTINJ_VALID) { + struct vmcb_control_area *nc = &nested_vmcb->control; + + nc->exit_int_info = vmcb->control.event_inj; + nc->exit_int_info_err = vmcb->control.event_inj_err; + } + + nested_vmcb->control.tlb_ctl = 0; + nested_vmcb->control.event_inj = 0; + nested_vmcb->control.event_inj_err = 0; + + nested_vmcb->control.pause_filter_count = + svm->vmcb->control.pause_filter_count; + nested_vmcb->control.pause_filter_thresh = + svm->vmcb->control.pause_filter_thresh; + + /* We always set V_INTR_MASKING and remember the old value in hflags */ + if (!(svm->vcpu.arch.hflags & HF_VINTR_MASK)) + nested_vmcb->control.int_ctl &= ~V_INTR_MASKING_MASK; + + /* Restore the original control entries */ + copy_vmcb_control_area(vmcb, hsave); + + svm->vcpu.arch.tsc_offset = svm->vmcb->control.tsc_offset; + kvm_clear_exception_queue(&svm->vcpu); + kvm_clear_interrupt_queue(&svm->vcpu); + + svm->nested.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); + if (npt_enabled) { + svm->vmcb->save.cr3 = hsave->save.cr3; + svm->vcpu.arch.cr3 = hsave->save.cr3; + } else { + (void)kvm_set_cr3(&svm->vcpu, hsave->save.cr3); + } + 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; + + mark_all_dirty(svm->vmcb); + + kvm_vcpu_unmap(&svm->vcpu, &map, true); + + nested_svm_uninit_mmu_context(&svm->vcpu); + kvm_mmu_reset_context(&svm->vcpu); + kvm_mmu_load(&svm->vcpu); + + /* + * 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; +} + +static int nested_svm_exit_handled_msr(struct vcpu_svm *svm) +{ + u32 offset, msr, value; + int write, mask; + + if (!(svm->nested.intercept & (1ULL << 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.vmcb_msrpm + offset, &value, 4)) + return NESTED_EXIT_DONE; + + return (value & mask) ? NESTED_EXIT_DONE : NESTED_EXIT_HOST; +} + +/* DB exceptions for our internal use must not cause vmexit */ +static int nested_svm_intercept_db(struct vcpu_svm *svm) +{ + unsigned long dr6; + + /* if we're not singlestepping, it's not ours */ + if (!svm->nmi_singlestep) + return NESTED_EXIT_DONE; + + /* if it's not a singlestep exception, it's not ours */ + if (kvm_get_dr(&svm->vcpu, 6, &dr6)) + return NESTED_EXIT_DONE; + if (!(dr6 & DR6_BS)) + return NESTED_EXIT_DONE; + + /* if the guest is singlestepping, it should get the vmexit */ + if (svm->nmi_singlestep_guest_rflags & X86_EFLAGS_TF) { + disable_nmi_singlestep(svm); + return NESTED_EXIT_DONE; + } + + /* it's ours, the nested hypervisor must not see this one */ + return 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 (!(svm->nested.intercept & (1ULL << 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.vmcb_iopm + (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: { + u32 bit = 1U << (exit_code - SVM_EXIT_READ_CR0); + if (svm->nested.intercept_cr & bit) + vmexit = NESTED_EXIT_DONE; + break; + } + case SVM_EXIT_READ_DR0 ... SVM_EXIT_WRITE_DR7: { + u32 bit = 1U << (exit_code - SVM_EXIT_READ_DR0); + if (svm->nested.intercept_dr & bit) + vmexit = NESTED_EXIT_DONE; + break; + } + case SVM_EXIT_EXCP_BASE ... SVM_EXIT_EXCP_BASE + 0x1f: { + u32 excp_bits = 1 << (exit_code - SVM_EXIT_EXCP_BASE); + if (svm->nested.intercept_exceptions & excp_bits) { + if (exit_code == SVM_EXIT_EXCP_BASE + DB_VECTOR) + vmexit = nested_svm_intercept_db(svm); + else + vmexit = NESTED_EXIT_DONE; + } + /* async page fault always cause vmexit */ + else if ((exit_code == SVM_EXIT_EXCP_BASE + PF_VECTOR) && + svm->vcpu.arch.exception.nested_apf != 0) + vmexit = NESTED_EXIT_DONE; + break; + } + case SVM_EXIT_ERR: { + vmexit = NESTED_EXIT_DONE; + break; + } + default: { + u64 exit_bits = 1ULL << (exit_code - SVM_EXIT_INTR); + if (svm->nested.intercept & exit_bits) + 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; +} + +int nested_svm_check_exception(struct vcpu_svm *svm, unsigned nr, + bool has_error_code, u32 error_code) +{ + int vmexit; + + if (!is_guest_mode(&svm->vcpu)) + return 0; + + vmexit = nested_svm_intercept(svm); + if (vmexit != NESTED_EXIT_DONE) + return 0; + + svm->vmcb->control.exit_code = SVM_EXIT_EXCP_BASE + nr; + svm->vmcb->control.exit_code_hi = 0; + svm->vmcb->control.exit_info_1 = error_code; + + /* + * EXITINFO2 is undefined for all exception intercepts other + * than #PF. + */ + 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; + + svm->nested.exit_required = true; + return vmexit; +} + +static void nested_svm_intr(struct vcpu_svm *svm) +{ + 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 this gets called afterwards from handle_exit */ + svm->nested.exit_required = true; + trace_kvm_nested_intr_vmexit(svm->vmcb->save.rip); +} + +static bool nested_exit_on_intr(struct vcpu_svm *svm) +{ + return (svm->nested.intercept & 1ULL); +} + +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.exit_required; + + if (kvm_cpu_has_interrupt(vcpu) && nested_exit_on_intr(svm)) { + if (block_nested_events) + return -EBUSY; + 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_EXCP_BASE + MC_VECTOR: + return NESTED_EXIT_HOST; + case SVM_EXIT_NPF: + /* For now we are always handling NPFs when using them */ + if (npt_enabled) + return NESTED_EXIT_HOST; + break; + case SVM_EXIT_EXCP_BASE + PF_VECTOR: + /* When we're shadowing, trap PFs, but not async PF */ + if (!npt_enabled && svm->vcpu.arch.apf.host_apf_reason == 0) + return NESTED_EXIT_HOST; + break; + default: + break; + } + + return NESTED_EXIT_CONTINUE; +} |