Re: [patch V3 13/33] x86/apic/vector: Provide MSI parent domain

[Thomas Gleixner <tglx@linutronix.de>]

Jason,

On Wed, Jan 04 2023 at 08:34, Jason Gunthorpe wrote:
> Our test team has discovered some kmem leak complaints on rc1 and
> bisected it to this patch.
>
> I don't see an obvious way that fwnode gets destroyed here. So maybe
> it should be like this?
>
> diff --git a/kernel/irq/msi.c b/kernel/irq/msi.c
> index 955267bbc2be63..cbbcb7fd2bd00d 100644
> --- a/kernel/irq/msi.c
> +++ b/kernel/irq/msi.c
> @@ -1000,7 +1000,7 @@ bool msi_create_device_irq_domain(struct device *dev, unsigned int domid,
>  fail:
>  	msi_unlock_descs(dev);
>  free_fwnode:
> -	kfree(fwnode);
> +	irq_domain_free_fwnode(fwnode); // ???

That's correct. kfree(fwnode) leaks fwnode->name

>  free_bundle:
>  	kfree(bundle);
>  	return false;
> @@ -1013,6 +1013,7 @@ bool msi_create_device_irq_domain(struct device *dev, unsigned int domid,
>   */
>  void msi_remove_device_irq_domain(struct device *dev, unsigned int domid)
>  {
> +	struct fwnode_handle *fwnode = NULL;
>  	struct msi_domain_info *info;
>  	struct irq_domain *domain;
>  
> @@ -1025,7 +1026,10 @@ void msi_remove_device_irq_domain(struct device *dev, unsigned int domid)
>  
>  	dev->msi.data->__domains[domid].domain = NULL;
>  	info = domain->host_data;
> +	if (domain->flags & IRQ_DOMAIN_FLAG_MSI_DEVICE)
> +		fwnode = domain->fwnode;

irq_domain_is_msi_device() ?

>  	irq_domain_remove(domain);
> +	irq_domain_free_fwnode(fwnode);

For some reason I thought the fwnode would be handled by
irq_domain_remove() but fwnode_handle_put() is a NOP for the named
fwnodes.

Care to send a proper patch with changelog?

Thanks,

        tglx