diff options
Diffstat (limited to 'arch/x86/kvm/vmx.c')
| -rw-r--r-- | arch/x86/kvm/vmx.c | 16 |
1 files changed, 11 insertions, 5 deletions
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index 3b4c8d8ad906..e6bf61fa1c03 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -1817,13 +1817,19 @@ u64 vmx_read_l1_tsc(struct kvm_vcpu *vcpu) } /* - * Empty call-back. Needs to be implemented when VMX enables the SET_TSC_KHZ - * ioctl. In this case the call-back should update internal vmx state to make - * the changes effective. + * Engage any workarounds for mis-matched TSC rates. Currently limited to + * software catchup for faster rates on slower CPUs. */ -static void vmx_set_tsc_khz(struct kvm_vcpu *vcpu, u32 user_tsc_khz) +static void vmx_set_tsc_khz(struct kvm_vcpu *vcpu, u32 user_tsc_khz, bool scale) { - /* Nothing to do here */ + if (!scale) + return; + + if (user_tsc_khz > tsc_khz) { + vcpu->arch.tsc_catchup = 1; + vcpu->arch.tsc_always_catchup = 1; + } else + WARN(1, "user requested TSC rate below hardware speed\n"); } /* |