Re: [PATCH 14/25] genirq: Update request_percpu_nmi() to take an affinity

[Thomas Gleixner <tglx@xxxxxxxxxxxxx>]

On Mon, Sep 08 2025 at 17:31, Marc Zyngier wrote:
> @@ -2564,13 +2566,14 @@ int request_percpu_nmi(unsigned int irq, irq_handler_t handler,
>  	    !irq_supports_nmi(desc))
>  		return -EINVAL;
>  
> -	/* The line cannot already be NMI */
> -	if (irq_is_nmi(desc))
> +	/* The line cannot be NMI already if the new request covers all CPUs */
> +	if (irq_is_nmi(desc) &&
> +	    (!affinity || cpumask_equal(affinity, cpu_possible_mask)))
>  		return -EINVAL;

This check looks odd. What makes sure that the affinities do not
overlap?

Thanks,

        tglx