kvm: clear kvmclock MSR on reset

After resetting the vCPU, the kvmclock MSR keeps the previous value but it is
not enabled.  This can be confusing, so fix it.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 41aecc4..5863c38 100644 (file)
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -2536,6 +2536,7 @@ static int kvm_pv_enable_async_pf(struct kvm_vcpu *vcpu, u64 data)
 static void kvmclock_reset(struct kvm_vcpu *vcpu)
 {
        vcpu->arch.pv_time_enabled = false;
+       vcpu->arch.time = 0;
 }
 
 static void kvm_vcpu_flush_tlb(struct kvm_vcpu *vcpu, bool invalidate_gpa)
@@ -2701,8 +2702,6 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
        case MSR_KVM_SYSTEM_TIME: {
                struct kvm_arch *ka = &vcpu->kvm->arch;
 
-               kvmclock_reset(vcpu);
-
                if (vcpu->vcpu_id == 0 && !msr_info->host_initiated) {
                        bool tmp = (msr == MSR_KVM_SYSTEM_TIME);
 
@@ -2716,14 +2715,13 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
                kvm_make_request(KVM_REQ_GLOBAL_CLOCK_UPDATE, vcpu);
 
                /* we verify if the enable bit is set... */
+               vcpu->arch.pv_time_enabled = false;
                if (!(data & 1))
                        break;
 
-               if (kvm_gfn_to_hva_cache_init(vcpu->kvm,
+               if (!kvm_gfn_to_hva_cache_init(vcpu->kvm,
                     &vcpu->arch.pv_time, data & ~1ULL,
                     sizeof(struct pvclock_vcpu_time_info)))
-                       vcpu->arch.pv_time_enabled = false;
-               else
                        vcpu->arch.pv_time_enabled = true;
 
                break;