From d6bf71a18c74de61548ddad44ff95306fe85f829 Mon Sep 17 00:00:00 2001 From: Vitaly Kuznetsov Date: Wed, 26 May 2021 15:20:22 +0200 Subject: [PATCH] KVM: nVMX: Ignore 'hv_clean_fields' data when eVMCS data is copied in vmx_get_nested_state() 'Clean fields' data from enlightened VMCS is only valid upon vmentry: L1 hypervisor is not obliged to keep it up-to-date while it is mangling L2's state, KVM_GET_NESTED_STATE request may come at a wrong moment when actual eVMCS changes are unsynchronized with 'hv_clean_fields'. As upon migration VMCS12 is used as a source of ultimate truth, we must make sure we pick all the changes to eVMCS and thus 'clean fields' data must be ignored. Signed-off-by: Vitaly Kuznetsov Signed-off-by: Paolo Bonzini Message-Id: <20210526132026.270394-8-vkuznets@redhat.com> Signed-off-by: Paolo Bonzini --- arch/x86/kvm/vmx/nested.c | 43 +++++++++++++++++++++++++------------------ 1 file changed, 25 insertions(+), 18 deletions(-) diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c index 6a3fdb90870a..3787be104ff0 100644 --- a/arch/x86/kvm/vmx/nested.c +++ b/arch/x86/kvm/vmx/nested.c @@ -1586,7 +1586,7 @@ static void copy_vmcs12_to_shadow(struct vcpu_vmx *vmx) vmcs_load(vmx->loaded_vmcs->vmcs); } -static void copy_enlightened_to_vmcs12(struct vcpu_vmx *vmx) +static void copy_enlightened_to_vmcs12(struct vcpu_vmx *vmx, u32 hv_clean_fields) { struct vmcs12 *vmcs12 = vmx->nested.cached_vmcs12; struct hv_enlightened_vmcs *evmcs = vmx->nested.hv_evmcs; @@ -1595,7 +1595,7 @@ static void copy_enlightened_to_vmcs12(struct vcpu_vmx *vmx) vmcs12->tpr_threshold = evmcs->tpr_threshold; vmcs12->guest_rip = evmcs->guest_rip; - if (unlikely(!(evmcs->hv_clean_fields & + if (unlikely(!(hv_clean_fields & HV_VMX_ENLIGHTENED_CLEAN_FIELD_GUEST_BASIC))) { vmcs12->guest_rsp = evmcs->guest_rsp; vmcs12->guest_rflags = evmcs->guest_rflags; @@ -1603,23 +1603,23 @@ static void copy_enlightened_to_vmcs12(struct vcpu_vmx *vmx) evmcs->guest_interruptibility_info; } - if (unlikely(!(evmcs->hv_clean_fields & + if (unlikely(!(hv_clean_fields & HV_VMX_ENLIGHTENED_CLEAN_FIELD_CONTROL_PROC))) { vmcs12->cpu_based_vm_exec_control = evmcs->cpu_based_vm_exec_control; } - if (unlikely(!(evmcs->hv_clean_fields & + if (unlikely(!(hv_clean_fields & HV_VMX_ENLIGHTENED_CLEAN_FIELD_CONTROL_EXCPN))) { vmcs12->exception_bitmap = evmcs->exception_bitmap; } - if (unlikely(!(evmcs->hv_clean_fields & + if (unlikely(!(hv_clean_fields & HV_VMX_ENLIGHTENED_CLEAN_FIELD_CONTROL_ENTRY))) { vmcs12->vm_entry_controls = evmcs->vm_entry_controls; } - if (unlikely(!(evmcs->hv_clean_fields & + if (unlikely(!(hv_clean_fields & HV_VMX_ENLIGHTENED_CLEAN_FIELD_CONTROL_EVENT))) { vmcs12->vm_entry_intr_info_field = evmcs->vm_entry_intr_info_field; @@ -1629,7 +1629,7 @@ static void copy_enlightened_to_vmcs12(struct vcpu_vmx *vmx) evmcs->vm_entry_instruction_len; } - if (unlikely(!(evmcs->hv_clean_fields & + if (unlikely(!(hv_clean_fields & HV_VMX_ENLIGHTENED_CLEAN_FIELD_HOST_GRP1))) { vmcs12->host_ia32_pat = evmcs->host_ia32_pat; vmcs12->host_ia32_efer = evmcs->host_ia32_efer; @@ -1649,7 +1649,7 @@ static void copy_enlightened_to_vmcs12(struct vcpu_vmx *vmx) vmcs12->host_tr_selector = evmcs->host_tr_selector; } - if (unlikely(!(evmcs->hv_clean_fields & + if (unlikely(!(hv_clean_fields & HV_VMX_ENLIGHTENED_CLEAN_FIELD_CONTROL_GRP1))) { vmcs12->pin_based_vm_exec_control = evmcs->pin_based_vm_exec_control; @@ -1658,18 +1658,18 @@ static void copy_enlightened_to_vmcs12(struct vcpu_vmx *vmx) evmcs->secondary_vm_exec_control; } - if (unlikely(!(evmcs->hv_clean_fields & + if (unlikely(!(hv_clean_fields & HV_VMX_ENLIGHTENED_CLEAN_FIELD_IO_BITMAP))) { vmcs12->io_bitmap_a = evmcs->io_bitmap_a; vmcs12->io_bitmap_b = evmcs->io_bitmap_b; } - if (unlikely(!(evmcs->hv_clean_fields & + if (unlikely(!(hv_clean_fields & HV_VMX_ENLIGHTENED_CLEAN_FIELD_MSR_BITMAP))) { vmcs12->msr_bitmap = evmcs->msr_bitmap; } - if (unlikely(!(evmcs->hv_clean_fields & + if (unlikely(!(hv_clean_fields & HV_VMX_ENLIGHTENED_CLEAN_FIELD_GUEST_GRP2))) { vmcs12->guest_es_base = evmcs->guest_es_base; vmcs12->guest_cs_base = evmcs->guest_cs_base; @@ -1709,14 +1709,14 @@ static void copy_enlightened_to_vmcs12(struct vcpu_vmx *vmx) vmcs12->guest_tr_selector = evmcs->guest_tr_selector; } - if (unlikely(!(evmcs->hv_clean_fields & + if (unlikely(!(hv_clean_fields & HV_VMX_ENLIGHTENED_CLEAN_FIELD_CONTROL_GRP2))) { vmcs12->tsc_offset = evmcs->tsc_offset; vmcs12->virtual_apic_page_addr = evmcs->virtual_apic_page_addr; vmcs12->xss_exit_bitmap = evmcs->xss_exit_bitmap; } - if (unlikely(!(evmcs->hv_clean_fields & + if (unlikely(!(hv_clean_fields & HV_VMX_ENLIGHTENED_CLEAN_FIELD_CRDR))) { vmcs12->cr0_guest_host_mask = evmcs->cr0_guest_host_mask; vmcs12->cr4_guest_host_mask = evmcs->cr4_guest_host_mask; @@ -1728,7 +1728,7 @@ static void copy_enlightened_to_vmcs12(struct vcpu_vmx *vmx) vmcs12->guest_dr7 = evmcs->guest_dr7; } - if (unlikely(!(evmcs->hv_clean_fields & + if (unlikely(!(hv_clean_fields & HV_VMX_ENLIGHTENED_CLEAN_FIELD_HOST_POINTER))) { vmcs12->host_fs_base = evmcs->host_fs_base; vmcs12->host_gs_base = evmcs->host_gs_base; @@ -1738,13 +1738,13 @@ static void copy_enlightened_to_vmcs12(struct vcpu_vmx *vmx) vmcs12->host_rsp = evmcs->host_rsp; } - if (unlikely(!(evmcs->hv_clean_fields & + if (unlikely(!(hv_clean_fields & HV_VMX_ENLIGHTENED_CLEAN_FIELD_CONTROL_XLAT))) { vmcs12->ept_pointer = evmcs->ept_pointer; vmcs12->virtual_processor_id = evmcs->virtual_processor_id; } - if (unlikely(!(evmcs->hv_clean_fields & + if (unlikely(!(hv_clean_fields & HV_VMX_ENLIGHTENED_CLEAN_FIELD_GUEST_GRP1))) { vmcs12->vmcs_link_pointer = evmcs->vmcs_link_pointer; vmcs12->guest_ia32_debugctl = evmcs->guest_ia32_debugctl; @@ -3509,7 +3509,7 @@ static int nested_vmx_run(struct kvm_vcpu *vcpu, bool launch) return nested_vmx_failInvalid(vcpu); if (evmptr_is_valid(vmx->nested.hv_evmcs_vmptr)) { - copy_enlightened_to_vmcs12(vmx); + copy_enlightened_to_vmcs12(vmx, vmx->nested.hv_evmcs->hv_clean_fields); /* Enlightened VMCS doesn't have launch state */ vmcs12->launch_state = !launch; } else if (enable_shadow_vmcs) { @@ -6155,7 +6155,14 @@ static int vmx_get_nested_state(struct kvm_vcpu *vcpu, copy_vmcs02_to_vmcs12_rare(vcpu, get_vmcs12(vcpu)); if (!vmx->nested.need_vmcs12_to_shadow_sync) { if (evmptr_is_valid(vmx->nested.hv_evmcs_vmptr)) - copy_enlightened_to_vmcs12(vmx); + /* + * L1 hypervisor is not obliged to keep eVMCS + * clean fields data always up-to-date while + * not in guest mode, 'hv_clean_fields' is only + * supposed to be actual upon vmentry so we need + * to ignore it here and do full copy. + */ + copy_enlightened_to_vmcs12(vmx, 0); else if (enable_shadow_vmcs) copy_shadow_to_vmcs12(vmx); } -- 2.11.0