Re: [PATCH v5 05/16] clocksource/hyperv: use MSR-based access if running as root

Wei Liu
2021-01-26T15:21:11Z

On Wed, Jan 20, 2021 at 11:13:28AM -0500, Pavel Tatashin wrote:
> On Wed, Jan 20, 2021 at 7:01 AM Wei Liu <wei.liu@kernel.org> wrote:
> >
> > When Linux runs as the root partition, the setup required for TSC page
> > is different.
>
> Why would we need a TSC page as a clock source for root partition at
> all? I think the above can be removed.
>

The TSC page is considered superior to MSR-based clock. In the future we
may want to switch back to that TSC page instead.

I think it provides more context than without.

Wei.

> Luckily Linux also has access to the MSR based
> > clocksource. We can just disable the TSC page clocksource if Linux is
> > the root partition.
> >