Re: [PATCH 1/2] genirq/msi: Introduce update hwsize helper

[Guixin Liu <kanie@linux.alibaba.com>]

在 2026/3/25 16:15, Thomas Gleixner 写道:
> On Tue, Mar 24 2026 at 09:47, Guixin Liu wrote:
>> +int msi_domain_update_hwsize(struct device *dev, unsigned int domid,
>> +			     unsigned int hwsize_new)
>> +{
>> +	struct msi_domain_info *info;
>> +	struct irq_domain *domain;
>> +
>> +	if (hwsize_new > MSI_XA_DOMAIN_SIZE)
>> +		return -EINVAL;
>> +	if (!hwsize_new)
>> +		hwsize_new = MSI_XA_DOMAIN_SIZE;
>> +
>> +	domain = msi_get_device_domain(dev, domid);
>> +	if (!domain)
>> +		return -ENODEV;
>> +
>> +	info = domain->host_data;
>> +	if (hwsize_new != info->hwsize)
>> +		info->hwsize = hwsize_new;
> This is incorrect because the underlying irqdomain has been created with
> the original hardware size. So just fiddling with info->hwsize results
> in inconsistent state.
I found that hwsize only affects the range checking when allocating and
releasing intterrupts after the irq_domain is established,
and the kernel does not allocate related resources based on it.
Cloud you plz tell me specifically where the inconsistency is? thanks.

Best Regards,
Guixin Liu