RE: [patch 15/20] genirq/msi: Provide new domain id allocation functions

[Thomas Gleixner <tglx@linutronix.de>]

On Fri, Nov 18 2022 at 08:43, Kevin Tian wrote:
>> From: Thomas Gleixner <tglx@linutronix.de>
>> Sent: Friday, November 11, 2022 9:57 PM
>> 
>> @@ -597,7 +598,7 @@ static struct irq_domain *msi_get_device
>>  	if (!domain)
>>  		return NULL;
>> 
>> -	if (WARN_ON_ONCE(irq_domain_is_msi_parent(domain)))
>> +	if (irq_domain_is_msi_parent(domain))
>>  		return NULL;
>
> Is it intended to remove the warning here? If yes, what specific change
> in this patch leads to that removal?

Valid question

>> +	xa_for_each_range(xa, idx, desc, ctrl->first + base, ctrl->last + base) {
>> +		if (!msi_desc_match(desc, MSI_DESC_NOTASSOCIATED))
>> +			continue;
>> +
>> +		/* This should return -ECONFUSED... */
>> +		if (WARN_ON_ONCE(allocated >= ctrl->nirqs))
>> +			return -EINVAL;
>> +
>
> why is "==" an error?

because if you get here _after_ having allocated all interrupts already
then you have more descriptors than what you want to allocate, which
should never happen right?

Thanks,

        tglx