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authorLinus Torvalds <torvalds@linux-foundation.org>2020-04-08 10:56:50 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2020-04-08 10:56:50 -0700
commit0339eb95403fb4664219be344a9399a3fdf1fae1 (patch)
tree76a6cb0d0cfcf8712867bf7c34cef078245f790b /arch/x86/kvm/svm/nested.c
parent9bb715260ed4cef6948cb2e05cf670462367da71 (diff)
parentdbef2808af6c594922fe32833b30f55f35e9da6d (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.c823
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;
+}