Re: [PATCH v5 1/3] xen/x86: add nmi continuation framework

[Jan Beulich <jbeulich@xxxxxxxx>]

On 12.11.2020 14:14, Juergen Gross wrote:
> --- a/xen/arch/x86/genapic/x2apic.c
> +++ b/xen/arch/x86/genapic/x2apic.c
> @@ -89,6 +89,7 @@ static unsigned int cpu_mask_to_apicid_x2apic_cluster(const 
> cpumask_t *cpumask)
>  
>  static void send_IPI_self_x2apic(uint8_t vector)
>  {
> +    /* NMI continuation handling relies on using a shorthand here. */
>      apic_wrmsr(APIC_SELF_IPI, vector);
>  }

I'm inclined to drop this hunk again - I did ask for ...

> --- a/xen/arch/x86/smp.c
> +++ b/xen/arch/x86/smp.c
> @@ -163,6 +163,7 @@ void send_IPI_self(int vector)
>  
>  void send_IPI_self_legacy(uint8_t vector)
>  {
> +    /* NMI continuation handling relies on using a shorthand here. */
>      send_IPI_shortcut(APIC_DEST_SELF, vector, APIC_DEST_PHYSICAL);
>  }

... this one only simply because x2APIC doesn't have the same restriction.

Jan