Re: [PATCH v7 10/10] Drivers: hv: Enable Hyper-V code to be built on ARM64

[Ben Dooks]

On 24/08/2020 18:24, Ard Biesheuvel wrote:
> On Mon, 24 Aug 2020 at 18:48, Michael Kelley <mikelley@xxxxxxxxxxxxx> wrote:
> > Update drivers/hv/Kconfig so CONFIG_HYPERV can be selected on
> > ARM64, causing the Hyper-V specific code to be built.
> >
> > Signed-off-by: Michael Kelley <mikelley@xxxxxxxxxxxxx>
> > ---
> >   drivers/hv/Kconfig | 3 ++-
> >   1 file changed, 2 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/hv/Kconfig b/drivers/hv/Kconfig
> > index 79e5356..1113e49 100644
> > --- a/drivers/hv/Kconfig
> > +++ b/drivers/hv/Kconfig
> > @@ -4,7 +4,8 @@ menu "Microsoft Hyper-V guest support"
> >
> >   config HYPERV
> >          tristate "Microsoft Hyper-V client drivers"
> > -       depends on X86 && ACPI && X86_LOCAL_APIC && HYPERVISOR_GUEST
> > +       depends on ACPI && \
> > +                       ((X86 && X86_LOCAL_APIC && HYPERVISOR_GUEST) || ARM64)
> >          select PARAVIRT
> >          select X86_HV_CALLBACK_VECTOR
> >          help
>
> Given the comment in a previous patch
>
> +/*
> + * All data structures defined in the TLFS that are shared between Hyper-V
> + * and a guest VM use Little Endian byte ordering.  This matches the default
> + * byte ordering of Linux running on ARM64, so no special handling is required.
> + */
>
> shouldn't this depend on !CONFIG_CPU_BIG_ENDIAN ?

or mark the data __le and have the appropriate accessor functions do
the swapping.


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Ben Dooks				http://www.codethink.co.uk/
Senior Engineer				Codethink - Providing Genius

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