Re: [PATCH v2 4/4] KVM: hyper-v: Advertise support for fast XMM hypercalls

Vitaly Kuznetsov
2021-04-13T14:26:59Z

Siddharth Chandrasekaran <sidcha@amazon.de> writes:

> Now that all extant hypercalls that can use XMM registers (based on
> spec) for input/outputs are patched to support them, we can start
> advertising this feature to guests.
>
> Cc: Alexander Graf <graf@amazon.com>
> Cc: Evgeny Iakovlev <eyakovl@amazon.de>
> Signed-off-by: Siddharth Chandrasekaran <sidcha@amazon.de>
> ---
> arch/x86/include/asm/hyperv-tlfs.h | 7 ++++++-
> arch/x86/kvm/hyperv.c | 2 ++
> 2 files changed, 8 insertions(+), 1 deletion(-)
>
> diff --git a/arch/x86/include/asm/hyperv-tlfs.h b/arch/x86/include/asm/hyperv-tlfs.h
> index e6cd3fee562b..716f12be411e 100644
> --- a/arch/x86/include/asm/hyperv-tlfs.h
> +++ b/arch/x86/include/asm/hyperv-tlfs.h
> @@ -52,7 +52,7 @@
> * Support for passing hypercall input parameter block via XMM
> * registers is available
> */
> -#define HV_X64_HYPERCALL_PARAMS_XMM_AVAILABLE BIT(4)
> +#define HV_X64_HYPERCALL_XMM_INPUT_AVAILABLE BIT(4)
> /* Support for a virtual guest idle state is available */
> #define HV_X64_GUEST_IDLE_STATE_AVAILABLE BIT(5)
> /* Frequency MSRs available */
> @@ -61,6 +61,11 @@
> #define HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE BIT(10)
> /* Support for debug MSRs available */
> #define HV_FEATURE_DEBUG_MSRS_AVAILABLE BIT(11)
> +/*
> + * Support for returning hypercall ouput block via XMM
> + * registers is available
> + */
> +#define HV_X64_HYPERCALL_XMM_OUTPUT_AVAILABLE BIT(15)
> /* stimer Direct Mode is available */
> #define HV_STIMER_DIRECT_MODE_AVAILABLE BIT(19)
>
> diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c
> index 1f9959aba70d..55838c266bcd 100644
> --- a/arch/x86/kvm/hyperv.c
> +++ b/arch/x86/kvm/hyperv.c
> @@ -2254,6 +2254,8 @@ int kvm_get_hv_cpuid(struct kvm_vcpu *vcpu, struct kvm_cpuid2 *cpuid,
> ent->ebx |= HV_POST_MESSAGES;
> ent->ebx |= HV_SIGNAL_EVENTS;
>
> + ent->edx |= HV_X64_HYPERCALL_XMM_INPUT_AVAILABLE;
> + ent->edx |= HV_X64_HYPERCALL_XMM_OUTPUT_AVAILABLE;
> ent->edx |= HV_FEATURE_FREQUENCY_MSRS_AVAILABLE;
> ent->edx |= HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE;

With 'ouput' typo fixed,

Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>

--
Vitaly