diff --git a/Documentation/virt/kvm/api.rst b/Documentation/virt/kvm/api.rst index d0569db2b1e2..db22e834ce2a 100644 --- a/Documentation/virt/kvm/api.rst +++ b/Documentation/virt/kvm/api.rst @@ -4334,9 +4334,13 @@ Errors: #define KVM_STATE_NESTED_VMX_SMM_GUEST_MODE 0x00000001 #define KVM_STATE_NESTED_VMX_SMM_VMXON 0x00000002 +#define KVM_STATE_VMX_PREEMPTION_TIMER_DEADLINE 0x00000001 + struct kvm_vmx_nested_state_hdr { + __u32 flags; __u64 vmxon_pa; __u64 vmcs12_pa; + __u64 preemption_timer_deadline; struct { __u16 flags; diff --git a/arch/x86/include/uapi/asm/kvm.h b/arch/x86/include/uapi/asm/kvm.h index 12075a9de1c1..17c5a038f42d 100644 --- a/arch/x86/include/uapi/asm/kvm.h +++ b/arch/x86/include/uapi/asm/kvm.h @@ -400,6 +400,7 @@ struct kvm_sync_regs { #define KVM_STATE_NESTED_SVM_VMCB_SIZE 0x1000 +#define KVM_STATE_VMX_PREEMPTION_TIMER_DEADLINE 0x00000001 struct kvm_vmx_nested_state_data { __u8 vmcs12[KVM_STATE_NESTED_VMX_VMCS_SIZE]; @@ -407,8 +408,10 @@ struct kvm_vmx_nested_state_data { }; struct kvm_vmx_nested_state_hdr { + __u32 flags; __u64 vmxon_pa; __u64 vmcs12_pa; + __u64 preemption_timer_deadline; struct { __u16 flags; diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c index 119a2f7395d6..da87bb8670bb 100644 --- a/arch/x86/kvm/vmx/nested.c +++ b/arch/x86/kvm/vmx/nested.c @@ -2087,9 +2087,29 @@ static enum hrtimer_restart vmx_preemption_timer_fn(struct hrtimer *timer) return HRTIMER_NORESTART; } -static void vmx_start_preemption_timer(struct kvm_vcpu *vcpu) +static u64 vmx_calc_preemption_timer_value(struct kvm_vcpu *vcpu) +{ + struct vcpu_vmx *vmx = to_vmx(vcpu); + struct vmcs12 *vmcs12 = get_vmcs12(vcpu); + u64 timer_value = 0; + + u64 l1_scaled_tsc = kvm_read_l1_tsc(vcpu, rdtsc()) >> + VMX_MISC_EMULATED_PREEMPTION_TIMER_RATE; + + if (!vmx->nested.has_preemption_timer_deadline) { + timer_value = vmcs12->vmx_preemption_timer_value; + vmx->nested.preemption_timer_deadline = timer_value + + l1_scaled_tsc; + vmx->nested.has_preemption_timer_deadline = true; + } else if (l1_scaled_tsc < vmx->nested.preemption_timer_deadline) + timer_value = vmx->nested.preemption_timer_deadline - + l1_scaled_tsc; + return timer_value; +} + +static void vmx_start_preemption_timer(struct kvm_vcpu *vcpu, + u64 preemption_timeout) { - u64 preemption_timeout = get_vmcs12(vcpu)->vmx_preemption_timer_value; struct vcpu_vmx *vmx = to_vmx(vcpu); /* @@ -3348,8 +3368,10 @@ enum nvmx_vmentry_status nested_vmx_enter_non_root_mode(struct kvm_vcpu *vcpu, * the timer. */ vmx->nested.preemption_timer_expired = false; - if (nested_cpu_has_preemption_timer(vmcs12)) - vmx_start_preemption_timer(vcpu); + if (nested_cpu_has_preemption_timer(vmcs12)) { + u64 timer_value = vmx_calc_preemption_timer_value(vcpu); + vmx_start_preemption_timer(vcpu, timer_value); + } /* * Note no nested_vmx_succeed or nested_vmx_fail here. At this point @@ -3457,6 +3479,7 @@ static int nested_vmx_run(struct kvm_vcpu *vcpu, bool launch) * the nested entry. */ vmx->nested.nested_run_pending = 1; + vmx->nested.has_preemption_timer_deadline = false; status = nested_vmx_enter_non_root_mode(vcpu, true); if (unlikely(status != NVMX_VMENTRY_SUCCESS)) goto vmentry_failed; @@ -3957,9 +3980,10 @@ static void sync_vmcs02_to_vmcs12(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12) vmcs12->guest_activity_state = GUEST_ACTIVITY_ACTIVE; if (nested_cpu_has_preemption_timer(vmcs12) && - vmcs12->vm_exit_controls & VM_EXIT_SAVE_VMX_PREEMPTION_TIMER) - vmcs12->vmx_preemption_timer_value = - vmx_get_preemption_timer_value(vcpu); + vmcs12->vm_exit_controls & VM_EXIT_SAVE_VMX_PREEMPTION_TIMER && + !vmx->nested.nested_run_pending) + vmcs12->vmx_preemption_timer_value = + vmx_get_preemption_timer_value(vcpu); /* * In some cases (usually, nested EPT), L2 is allowed to change its @@ -5891,8 +5915,10 @@ static int vmx_get_nested_state(struct kvm_vcpu *vcpu, .flags = 0, .format = KVM_STATE_NESTED_FORMAT_VMX, .size = sizeof(kvm_state), + .hdr.vmx.flags = 0, .hdr.vmx.vmxon_pa = -1ull, .hdr.vmx.vmcs12_pa = -1ull, + .hdr.vmx.preemption_timer_deadline = 0, }; struct kvm_vmx_nested_state_data __user *user_vmx_nested_state = &user_kvm_nested_state->data.vmx[0]; @@ -5934,6 +5960,14 @@ static int vmx_get_nested_state(struct kvm_vcpu *vcpu, if (vmx->nested.mtf_pending) kvm_state.flags |= KVM_STATE_NESTED_MTF_PENDING; + + if (nested_cpu_has_preemption_timer(vmcs12) && + vmx->nested.has_preemption_timer_deadline) { + kvm_state.hdr.vmx.flags |= + KVM_STATE_VMX_PREEMPTION_TIMER_DEADLINE; + kvm_state.hdr.vmx.preemption_timer_deadline = + vmx->nested.preemption_timer_deadline; + } } } @@ -5979,7 +6013,6 @@ static int vmx_get_nested_state(struct kvm_vcpu *vcpu, get_shadow_vmcs12(vcpu), VMCS12_SIZE)) return -EFAULT; } - out: return kvm_state.size; } @@ -6141,6 +6174,12 @@ static int vmx_set_nested_state(struct kvm_vcpu *vcpu, goto error_guest_mode; } + if (kvm_state->hdr.vmx.flags & KVM_STATE_VMX_PREEMPTION_TIMER_DEADLINE) { + vmx->nested.has_preemption_timer_deadline = true; + vmx->nested.preemption_timer_deadline = + kvm_state->hdr.vmx.preemption_timer_deadline; + } + if (nested_vmx_check_controls(vcpu, vmcs12) || nested_vmx_check_host_state(vcpu, vmcs12) || nested_vmx_check_guest_state(vcpu, vmcs12, &ignored)) diff --git a/arch/x86/kvm/vmx/vmx.h b/arch/x86/kvm/vmx/vmx.h index 298ddef79d00..672c28f17e49 100644 --- a/arch/x86/kvm/vmx/vmx.h +++ b/arch/x86/kvm/vmx/vmx.h @@ -169,6 +169,8 @@ struct nested_vmx { u16 posted_intr_nv; struct hrtimer preemption_timer; + u64 preemption_timer_deadline; + bool has_preemption_timer_deadline; bool preemption_timer_expired; /* to migrate it to L2 if VM_ENTRY_LOAD_DEBUG_CONTROLS is off */