Re: [PATCH] PCI/MSI: Fix memory leak in pci_alloc_irq_vectors_affinity INTx path

[Hans Zhang <18255117159@163.com>]

On 4/20/26 12:09, neilfsun wrote:
> In the INTx fallback path of pci_alloc_irq_vectors_affinity(),
> affinity masks are created and never freed.
> 
> Signed-off-by: neilfsun <neilfsun@tencent.com>
> Signed-off-by: Sun Feng <loyou85@gmail.com>
> ---
>   drivers/pci/msi/api.c | 5 ++++-
>   1 file changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/pci/msi/api.c b/drivers/pci/msi/api.c
> index c18559b6272c..c1377f74b8f3 100644
> --- a/drivers/pci/msi/api.c
> +++ b/drivers/pci/msi/api.c
> @@ -280,14 +280,17 @@ int pci_alloc_irq_vectors_affinity(struct pci_dev *dev, unsigned int min_vecs,
>   	/* use INTx IRQ if allowed */
>   	if (flags & PCI_IRQ_INTX) {
>   		if (min_vecs == 1 && dev->irq) {
> +			struct irq_affinity_desc *masks = NULL;
> +
>   			/*
>   			 * Invoke the affinity spreading logic to ensure that
>   			 * the device driver can adjust queue configuration
>   			 * for the single interrupt case.
>   			 */
>   			if (affd)
> -				irq_create_affinity_masks(1, affd);
> +				masks = irq_create_affinity_masks(1, affd);

Hi,

Suggestion:

diff --git a/drivers/pci/msi/api.c b/drivers/pci/msi/api.c
index c18559b6272c..0ce34db2b2bf 100644
--- a/drivers/pci/msi/api.c
+++ b/drivers/pci/msi/api.c
@@ -286,7 +286,8 @@ int pci_alloc_irq_vectors_affinity(struct pci_dev 
*dev, unsigned int min_vecs,
                          * for the single interrupt case.
                          */
                         if (affd)
-                               irq_create_affinity_masks(1, affd);
+                               struct irq_affinity_desc *masks 
__free(kfree) =
+                                       irq_create_affinity_masks(1, affd);
                         pci_intx(dev, 1);
                         return 1;
                 }


Best regards,
Hans

>   			pci_intx(dev, 1);
> +			kfree(masks);
>   			return 1;
>   		}
>   	}