diff options
Diffstat (limited to 'drivers/kvm')
| -rw-r--r-- | drivers/kvm/kvm.h | 1 | ||||
| -rw-r--r-- | drivers/kvm/svm.c | 21 |
2 files changed, 18 insertions, 4 deletions
diff --git a/drivers/kvm/kvm.h b/drivers/kvm/kvm.h index f5e343cb06b0..6d0bd7aab92e 100644 --- a/drivers/kvm/kvm.h +++ b/drivers/kvm/kvm.h @@ -244,6 +244,7 @@ struct kvm_vcpu { struct mutex mutex; int cpu; int launched; + u64 host_tsc; struct kvm_run *run; int interrupt_window_open; unsigned long irq_summary; /* bit vector: 1 per word in irq_pending */ diff --git a/drivers/kvm/svm.c b/drivers/kvm/svm.c index 0542d3357ce1..ca2642fc091f 100644 --- a/drivers/kvm/svm.c +++ b/drivers/kvm/svm.c @@ -459,7 +459,6 @@ static void init_vmcb(struct vmcb *vmcb) { struct vmcb_control_area *control = &vmcb->control; struct vmcb_save_area *save = &vmcb->save; - u64 tsc; control->intercept_cr_read = INTERCEPT_CR0_MASK | INTERCEPT_CR3_MASK | @@ -517,8 +516,7 @@ static void init_vmcb(struct vmcb *vmcb) control->iopm_base_pa = iopm_base; control->msrpm_base_pa = msrpm_base; - rdtscll(tsc); - control->tsc_offset = -tsc; + control->tsc_offset = 0; control->int_ctl = V_INTR_MASKING_MASK; init_seg(&save->es); @@ -606,11 +604,26 @@ static void svm_free_vcpu(struct kvm_vcpu *vcpu) static void svm_vcpu_load(struct kvm_vcpu *vcpu) { - get_cpu(); + int cpu; + + cpu = get_cpu(); + if (unlikely(cpu != vcpu->cpu)) { + u64 tsc_this, delta; + + /* + * Make sure that the guest sees a monotonically + * increasing TSC. + */ + rdtscll(tsc_this); + delta = vcpu->host_tsc - tsc_this; + vcpu->svm->vmcb->control.tsc_offset += delta; + vcpu->cpu = cpu; + } } static void svm_vcpu_put(struct kvm_vcpu *vcpu) { + rdtscll(vcpu->host_tsc); put_cpu(); } |