On 28/11/2016 15:28, Eduardo Habkost wrote: > > + s->src_use_reliable_get_clock = data.flags & KVM_CLOCK_TSC_STABLE; > > I still don't understand the reasoning behind > kvm_has_adjust_clock_stable() vs (flags & KVM_CLOCK_TSC_STABLE), > but on either case, updating src_use_reliable_get_clock inside > kvm_get_clock() looks like the right thing to do. There are three possibility: the kernel tells you the clock is stable, the kernel tells you the clock is unstable, the kernel is too old and doesn't tell you anything. Then: kvm_has_adjust_clock_stable() == true: if the clock is stable, KVM_CLOCK_TSC_STABLE will be set in "flags" if the clock is unstable, KVM_CLOCK_TSC_STABLE will be unset kvm_has_adjust_clock_stable() == false: you cannot know if the clock is stable Paolo -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html