Re: [PATCH v11 0/5] Enable Linux guests on Hyper-V on ARM64

From: Marc Zyngier
Date: Mon Aug 02 2021 - 12:01:07 EST


On Tue, 20 Jul 2021 15:56:58 +0100,
Michael Kelley <mikelley@xxxxxxxxxxxxx> wrote:
>
> This series enables Linux guests running on Hyper-V on ARM64
> hardware. New ARM64-specific code in arch/arm64/hyperv initializes
> Hyper-V and its hypercall mechanism. Existing architecture
> independent drivers for Hyper-V's VMbus and synthetic devices just
> work when built for ARM64. Hyper-V code is built and included in
> the image and modules only if CONFIG_HYPERV is enabled.
>
> The five patches are organized as follows:
>
> 1) Add definitions and functions for making Hyper-V hypercalls
> and getting/setting virtual processor registers provided by
> Hyper-V
>
> 2) Add the function needed by the arch independent VMbus driver
> for reporting a panic to Hyper-V.
>
> 3) Add Hyper-V initialization code and utility functions that
> report Hyper-v status.
>
> 4) Export screen_info so it may be used by the Hyper-V frame buffer
> driver built as a module. It is already exported for x86,
> powerpc, and alpha architectures.
>
> 5) Make CONFIG_HYPERV selectable on ARM64 in addition to x86/x64.
>
> Hyper-V on ARM64 runs with a 4 Kbyte page size, but allows guests
> with 4K/16K/64K page size. Linux guests with this patch series
> work with all three supported ARM64 page sizes.
>
> The Hyper-V vPCI driver at drivers/pci/host/pci-hyperv.c has
> x86/x64-specific code and is not being built for ARM64. Enabling
> Hyper-V vPCI devices on ARM64 is in progress via a separate set
> of patches.
>
> This patch set is based on the linux-next20210720 code tree.
>
> Changes in v11:
> * Drop the previous Patch 1 as the fixes have already been
> separately accepted upstream.
> * Drop the previous Patch 3 for enabling Hyper-V enlightened
> clocks/timers. Hyper-V is now offering the full ARM64
> architectural Generic Timer in guest VMs, so the existing
> arch_arch_timer.c driver just works. [Mark Rutland, Marc
> Zyngier]

Thanks for doing this. Assuming you fix the issue I mentioned in my
reply to patch #3. FWIW:

Acked-by: Marc Zyngier <maz@xxxxxxxxxx>

M.

--
Without deviation from the norm, progress is not possible.