diff options
author | Vitaly Kuznetsov <vkuznets@redhat.com> | 2020-03-09 16:52:13 +0100 |
---|---|---|
committer | Paolo Bonzini <pbonzini@redhat.com> | 2020-03-16 18:19:30 +0100 |
commit | b6a0653ae2cd71a58f479b46ff20307dd3540d63 (patch) | |
tree | f18c9b0c24fd51d391bd77080639960efcab9ff7 /arch | |
parent | e942dbf8c58e1bf1ccfe18eb2713e3b360ec2e7f (diff) | |
download | linux-b6a0653ae2cd71a58f479b46ff20307dd3540d63.tar.bz2 |
KVM: nVMX: properly handle errors in nested_vmx_handle_enlightened_vmptrld()
nested_vmx_handle_enlightened_vmptrld() fails in two cases:
- when we fail to kvm_vcpu_map() the supplied GPA
- when revision_id is incorrect.
Genuine Hyper-V raises #UD in the former case (at least with *some*
incorrect GPAs) and does VMfailInvalid() in the later. KVM doesn't do
anything so L1 just gets stuck retrying the same faulty VMLAUNCH.
nested_vmx_handle_enlightened_vmptrld() has two call sites:
nested_vmx_run() and nested_get_vmcs12_pages(). The former needs to queue
do much: the failure there happens after migration when L2 was running (and
L1 did something weird like wrote to VP assist page from a different vCPU),
just kill L1 with KVM_EXIT_INTERNAL_ERROR.
Reported-by: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
[Squash kbuild autopatch. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch')
-rw-r--r-- | arch/x86/kvm/vmx/evmcs.h | 7 | ||||
-rw-r--r-- | arch/x86/kvm/vmx/nested.c | 39 |
2 files changed, 36 insertions, 10 deletions
diff --git a/arch/x86/kvm/vmx/evmcs.h b/arch/x86/kvm/vmx/evmcs.h index 6de47f2569c9..e5f7a7ebf27d 100644 --- a/arch/x86/kvm/vmx/evmcs.h +++ b/arch/x86/kvm/vmx/evmcs.h @@ -198,6 +198,13 @@ static inline void evmcs_sanitize_exec_ctrls(struct vmcs_config *vmcs_conf) {} static inline void evmcs_touch_msr_bitmap(void) {} #endif /* IS_ENABLED(CONFIG_HYPERV) */ +enum nested_evmptrld_status { + EVMPTRLD_DISABLED, + EVMPTRLD_SUCCEEDED, + EVMPTRLD_VMFAIL, + EVMPTRLD_ERROR, +}; + bool nested_enlightened_vmentry(struct kvm_vcpu *vcpu, u64 *evmcs_gpa); uint16_t nested_get_evmcs_version(struct kvm_vcpu *vcpu); int nested_enable_evmcs(struct kvm_vcpu *vcpu, diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c index 424d9a77af86..8578513907d7 100644 --- a/arch/x86/kvm/vmx/nested.c +++ b/arch/x86/kvm/vmx/nested.c @@ -1909,18 +1909,18 @@ static int copy_vmcs12_to_enlightened(struct vcpu_vmx *vmx) * This is an equivalent of the nested hypervisor executing the vmptrld * instruction. */ -static int nested_vmx_handle_enlightened_vmptrld(struct kvm_vcpu *vcpu, - bool from_launch) +static enum nested_evmptrld_status nested_vmx_handle_enlightened_vmptrld( + struct kvm_vcpu *vcpu, bool from_launch) { struct vcpu_vmx *vmx = to_vmx(vcpu); bool evmcs_gpa_changed = false; u64 evmcs_gpa; if (likely(!vmx->nested.enlightened_vmcs_enabled)) - return 1; + return EVMPTRLD_DISABLED; if (!nested_enlightened_vmentry(vcpu, &evmcs_gpa)) - return 1; + return EVMPTRLD_DISABLED; if (unlikely(!vmx->nested.hv_evmcs || evmcs_gpa != vmx->nested.hv_evmcs_vmptr)) { @@ -1931,7 +1931,7 @@ static int nested_vmx_handle_enlightened_vmptrld(struct kvm_vcpu *vcpu, if (kvm_vcpu_map(vcpu, gpa_to_gfn(evmcs_gpa), &vmx->nested.hv_evmcs_map)) - return 0; + return EVMPTRLD_ERROR; vmx->nested.hv_evmcs = vmx->nested.hv_evmcs_map.hva; @@ -1960,7 +1960,7 @@ static int nested_vmx_handle_enlightened_vmptrld(struct kvm_vcpu *vcpu, if ((vmx->nested.hv_evmcs->revision_id != KVM_EVMCS_VERSION) && (vmx->nested.hv_evmcs->revision_id != VMCS12_REVISION)) { nested_release_evmcs(vcpu); - return 0; + return EVMPTRLD_VMFAIL; } vmx->nested.dirty_vmcs12 = true; @@ -1989,7 +1989,7 @@ static int nested_vmx_handle_enlightened_vmptrld(struct kvm_vcpu *vcpu, vmx->nested.hv_evmcs->hv_clean_fields &= ~HV_VMX_ENLIGHTENED_CLEAN_FIELD_ALL; - return 1; + return EVMPTRLD_SUCCEEDED; } void nested_sync_vmcs12_to_shadow(struct kvm_vcpu *vcpu) @@ -3059,8 +3059,21 @@ static bool nested_get_vmcs12_pages(struct kvm_vcpu *vcpu) * L2 was running), map it here to make sure vmcs12 changes are * properly reflected. */ - if (vmx->nested.enlightened_vmcs_enabled && !vmx->nested.hv_evmcs) - nested_vmx_handle_enlightened_vmptrld(vcpu, false); + if (vmx->nested.enlightened_vmcs_enabled && !vmx->nested.hv_evmcs) { + enum nested_evmptrld_status evmptrld_status = + nested_vmx_handle_enlightened_vmptrld(vcpu, false); + + if (evmptrld_status == EVMPTRLD_VMFAIL || + evmptrld_status == EVMPTRLD_ERROR) { + pr_debug_ratelimited("%s: enlightened vmptrld failed\n", + __func__); + vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR; + vcpu->run->internal.suberror = + KVM_INTERNAL_ERROR_EMULATION; + vcpu->run->internal.ndata = 0; + return false; + } + } if (nested_cpu_has2(vmcs12, SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES)) { /* @@ -3325,12 +3338,18 @@ static int nested_vmx_run(struct kvm_vcpu *vcpu, bool launch) enum nvmx_vmentry_status status; struct vcpu_vmx *vmx = to_vmx(vcpu); u32 interrupt_shadow = vmx_get_interrupt_shadow(vcpu); + enum nested_evmptrld_status evmptrld_status; if (!nested_vmx_check_permission(vcpu)) return 1; - if (!nested_vmx_handle_enlightened_vmptrld(vcpu, launch)) + evmptrld_status = nested_vmx_handle_enlightened_vmptrld(vcpu, launch); + if (evmptrld_status == EVMPTRLD_ERROR) { + kvm_queue_exception(vcpu, UD_VECTOR); return 1; + } else if (evmptrld_status == EVMPTRLD_VMFAIL) { + return nested_vmx_failInvalid(vcpu); + } if (!vmx->nested.hv_evmcs && vmx->nested.current_vmptr == -1ull) return nested_vmx_failInvalid(vcpu); |