Re: [PATCH 16/16] PCI: vmd: Switch to msi_create_parent_irq_domain()

[Antonio Quartulli]

Hi Nam,

On 26/06/2025 16:48, Nam Cao wrote:
[...]
> -static void vmd_msi_free(struct irq_domain *domain,
> -			struct msi_domain_info *info, unsigned int virq)
> +static void vmd_msi_free(struct irq_domain *domain, unsigned int virq, unsigned int nr_irqs)
>   {
>   	struct vmd_irq *vmdirq = irq_get_chip_data(virq);
>   
> -	synchronize_srcu(&vmdirq->irq->srcu);
> +	for (int i = 0; i < nr_irqs; ++i) {
> +		synchronize_srcu(&vmdirq->irq->srcu);
>   
> -	/* XXX: Potential optimization to rebalance */
> -	scoped_guard(raw_spinlock_irq, &list_lock)
> -		vmdirq->irq->count--;
> +		/* XXX: Potential optimization to rebalance */
> +		scoped_guard(raw_spinlock_irq, &list_lock)
> +			vmdirq->irq->count--;
>   
> -	kfree(vmdirq);
> +		kfree(vmdirq);
> +	}

By introducing a for loop in this function, you are re-using vmdirq 
after free'ing it.

I can't send a patch because I am not faimliar with this API and I don't 
know how to fix it.

However, the issue was reported today by Coverity.

Any idea? :-)

Regards,

--
Antonio Quartulli

CEO and Co-Founder
Mandelbit Srl
https://www.mandelbit.com