Re: [PATCH v2] clocksource: hyper-v: Use lapic timer in a TDX VM without paravisor

[Wei Liu]

On Thu, Jun 20, 2024 at 11:16:14PM -0700, Dexuan Cui wrote:
> In a TDX VM without paravisor, currently the default timer is the Hyper-V
> timer, which depends on the slow VM Reference Counter MSR: the Hyper-V TSC
> page is not enabled in such a VM because the VM uses Invariant TSC as a
> better clocksource and it's challenging to mark the Hyper-V TSC page shared
> in very early boot.
> 
> Lower the rating of the Hyper-V timer so the local APIC timer becomes the
> the default timer in such a VM, and print a warning in case Invariant TSC
> is unavailable in such a VM. This change should cause no perceivable
> performance difference.
> 
> Cc: stable@xxxxxxxxxxxxxxx # 6.6+
> Reviewed-by: Roman Kisel <romank@xxxxxxxxxxxxxxxxxxx>
> Signed-off-by: Dexuan Cui <decui@xxxxxxxxxxxxx>

Applied to hyperv-fixes. Thanks.