Re: [PATCH v5 13/14] x86/tsc: Mark Secure TSC as reliable clocksource

From: Kirill A. Shutemov
Date: Mon Nov 06 2023 - 08:04:10 EST


On Mon, Nov 06, 2023 at 05:23:44PM +0530, Nikunj A. Dadhania wrote:
> > Maybe kvmclock rating has to be even lower after detecting sane TSC?
>
> If I set kvmclock rating to 298, I do see exact behavior as you have seen on the bare-metal.
>
> [ 0.004520] clocksource: clocksource_enqueue: name kvm-clock rating 298
> [...]
> [ 1.827422] clocksource: clocksource_enqueue: name tsc-early rating 299
> [...]
> [ 3.485059] clocksource: Switched to clocksource tsc-early
> [...]
> [ 3.623625] clocksource: clocksource_enqueue: name tsc rating 300
> [ 3.628954] clocksource: Switched to clocksource tsc

This looks more reasonable to me. But I don't really understand
timekeeping. It would be nice to hear from someone who knows what he
saying.

--
Kiryl Shutsemau / Kirill A. Shutemov