Re: [RFC PATCH v2 45/45] irqchip/gic-v5: Add NMI support for IPIs

On 8/7/26 11:57, Marc Zyngier wrote:
> On Fri, 07 Aug 2026 11:42:12 +0100,
> Vladimir Murzin <[email protected]> wrote:
>> On 8/7/26 11:17, Marc Zyngier wrote:
>>> On Mon, 27 Jul 2026 17:34:53 +0100,
>>> Vladimir Murzin <[email protected]> wrote:
>>>> diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
>>>> index 7eb07e3bdb4c..0091bb5f7662 100644
>>>> --- a/kernel/irq/manage.c
>>>> +++ b/kernel/irq/manage.c
>>>> @@ -1370,9 +1370,14 @@ static bool irq_supports_nmi(struct irq_desc *desc)
>>>>  	struct irq_data *d = irq_desc_get_irq_data(desc);
>>>>  
>>>>  #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
>>>> -	/* Only IRQs directly managed by the root irqchip can be set as NMI */
>>>> -	if (d->parent_data)
>>>> -		return false;
>>>> +	struct irq_data *data;
>>>> +	/*
>>>> +	 * Only IRQs directly managed by the root irqchip can be set
>>>> +	 * as NMI unless we inherit NMI from parent
>>>> +	 */
>>>> +	for (data = d->parent_data; data; data = data->parent_data)
>>>> +		if (!(data->chip && data->chip->flags & IRQCHIP_SUPPORTS_NMI))
>>>> +			return false;
>>> Maybe we should just trust the local irqchip to do the right
>>> thing. After all, the core code shouldn't be in the business of
>>> sanitising broken irqchip drivers advertising random crap.
>>>
>> That is indeed bit I was not really sure about, if we decide that we
>> can trust local irqchip then I assume we just drop the check?
> Yup. Drop the CONFIG_IRQ_DOMAIN_HIERARCHY hack, and only consider the
> local information.
> 

Got it! Thanks!

Vladimir

> Thanks,
> 
> 	M.
> 
> -- Without deviation from the norm, progress is not possible.
>