[PATCH 00/16] KVM: arm64: Rework timer offsetting for fun and profit

[Veith, Simon]

Hello Marc,

On Thu, 2023-02-16 at 14:21 +0000, Marc Zyngier wrote:
> This series aims at satisfying multiple goals:
> 
> - allow a VMM to atomically restore a timer offset for a whole VM
>   instead of updating the offset each time a vcpu get its counter
>   written
> 
> - allow a VMM to save/restore the physical timer context, something
>   that we cannot do at the moment due to the lack of offsetting
> 
> - provide a framework that is suitable for NV support, where we get
>   both global and per timer, per vcpu offsetting

Thank you so much for following up on my (admittedly very basic) patch
with your own proposal!

> This has been moderately tested with nVHE, VHE and NV. I do not have
> access to CNTPOFF-aware HW, so the jury is still out on that one

Same here about CNTPOFF -- I gave it a quick spin on Graviton2 and
Graviton3, and neither chip claims the ARM64_HAS_ECV_CNTPOFF capability
from your patch.

I am working on testing your series with our userspace and will report
back.

Thanks
Simon



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