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Diffstat (limited to 'arch/x86/kvm/svm.c')
-rw-r--r--arch/x86/kvm/svm.c20
1 files changed, 12 insertions, 8 deletions
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 7bbd17cc348..e12026e5244 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -964,20 +964,25 @@ static u64 svm_scale_tsc(struct kvm_vcpu *vcpu, u64 tsc)
return _tsc;
}
-static void svm_set_tsc_khz(struct kvm_vcpu *vcpu, u32 user_tsc_khz)
+static void svm_set_tsc_khz(struct kvm_vcpu *vcpu, u32 user_tsc_khz, bool scale)
{
struct vcpu_svm *svm = to_svm(vcpu);
u64 ratio;
u64 khz;
- /* TSC scaling supported? */
- if (!boot_cpu_has(X86_FEATURE_TSCRATEMSR))
+ /* Guest TSC same frequency as host TSC? */
+ if (!scale) {
+ svm->tsc_ratio = TSC_RATIO_DEFAULT;
return;
+ }
- /* TSC-Scaling disabled or guest TSC same frequency as host TSC? */
- if (user_tsc_khz == 0) {
- vcpu->arch.virtual_tsc_khz = 0;
- svm->tsc_ratio = TSC_RATIO_DEFAULT;
+ /* TSC scaling supported? */
+ if (!boot_cpu_has(X86_FEATURE_TSCRATEMSR)) {
+ 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");
return;
}
@@ -992,7 +997,6 @@ static void svm_set_tsc_khz(struct kvm_vcpu *vcpu, u32 user_tsc_khz)
user_tsc_khz);
return;
}
- vcpu->arch.virtual_tsc_khz = user_tsc_khz;
svm->tsc_ratio = ratio;
}