On 16/03/2018 16:05, Vitaly Kuznetsov wrote: >>> >>> - if (has_msr_hv_frequencies && tsc_is_stable_and_known(env)) { >>> + if (has_msr_hv_frequencies && env->tsc_khz) { >> Should this be >> >> ((env->tsc_khz && has_msr_hv_reenlightenment) || >> tsc_is_stable_and_known(env)) >> >> so that you don't regress on older kernels? >> > I don't actually see where the regression might come from: frequency > MSRs are supported regardless or reenlightenment/invtsc and there's > nothing wrong with exposing them but I may be missing something..
On older kernel without re-enlightenment support, you don't want to expose the frequency MSRs unless invtsc is on, right? Paolo