Re: [RFC v2 11/14] linux-headers/kvm.h: add capability to forward hypercall

[Cornelia Huck]

On Tue, 5 Nov 2019 17:10:53 +0800
Heyi Guo <address@hidden> wrote:

> To keep backward compatibility, we add new KVM capability
> "KVM_CAP_FORWARD_HYPERCALL" to probe whether KVM supports forwarding
> hypercall to userspace.
> 
> The capability should be enabled explicitly, for we don't want user
> space application to deal with unexpected hypercall exits. After
> enabling this cap, all HVC calls unhandled by kvm will be forwarded to
> user space.
> 
> Signed-off-by: Heyi Guo <address@hidden>
> Cc: Peter Maydell <address@hidden>
> Cc: "Michael S. Tsirkin" <address@hidden>
> Cc: Cornelia Huck <address@hidden>
> Cc: Paolo Bonzini <address@hidden>
> Cc: Dave Martin <address@hidden>
> Cc: Marc Zyngier <address@hidden>
> Cc: Mark Rutland <address@hidden>
> Cc: James Morse <address@hidden>
> ---
>  linux-headers/linux/kvm.h |  1 +
>  target/arm/sdei.c         | 16 ++++++++++++++++
>  target/arm/sdei.h         |  2 ++
>  3 files changed, 19 insertions(+)
> 
> diff --git a/linux-headers/linux/kvm.h b/linux-headers/linux/kvm.h
> index 3d9b18f7f8..36c9b3859f 100644
> --- a/linux-headers/linux/kvm.h
> +++ b/linux-headers/linux/kvm.h
> @@ -1000,6 +1000,7 @@ struct kvm_ppc_resize_hpt {
>  #define KVM_CAP_PMU_EVENT_FILTER 173
>  #define KVM_CAP_ARM_IRQ_LINE_LAYOUT_2 174
>  #define KVM_CAP_HYPERV_DIRECT_TLBFLUSH 175
> +#define KVM_CAP_FORWARD_HYPERCALL 176
>  
>  #ifdef KVM_CAP_IRQ_ROUTING

Is this cap upstream already? I would have thought your header sync
would have brought it in, then. (Saying this, that header sync looks
awfully small.)

If it is not upstream yet, please split off this hunk into a separate
patch -- it's a bit annoying, but makes life easier for merging.