From: Zachary Amsden <[email protected]> When CPUs with unstable TSCs enter deep C-state, TSC may stop running. This causes us to require resynchronization. Since we can't tell when this may potentially happen, we assume the worst by forcing re-compensation for it at every point the VCPU task is descheduled.
Signed-off-by: Zachary Amsden <[email protected]> Signed-off-by: Marcelo Tosatti <[email protected]> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 547293b..e5b3aa9 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -1866,7 +1866,7 @@ void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu) } kvm_x86_ops->vcpu_load(vcpu, cpu); - if (unlikely(vcpu->cpu != cpu)) { + if (unlikely(vcpu->cpu != cpu) || check_tsc_unstable()) { /* Make sure TSC doesn't go backwards */ s64 tsc_delta = !vcpu->arch.last_host_tsc ? 0 : native_read_tsc() - vcpu->arch.last_host_tsc; -- To unsubscribe from this list: send the line "unsubscribe kvm-commits" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
