Re: [PATCH 3/4] nvme: pci: pass IRQF_RESCURE_THREAD to request_threaded_irq

Ming Lei
2019-08-27T09:09:43Z

On Tue, Aug 27, 2019 at 11:06:20AM +0200, Johannes Thumshirn wrote:
> On 27/08/2019 10:53, Ming Lei wrote:
> [...]
> > + char *devname;
> > + const struct cpumask *mask;
> > + unsigned long irqflags = IRQF_SHARED;
> > + int vector = pci_irq_vector(pdev, nvmeq->cq_vector);
> > +
> > + devname = kasprintf(GFP_KERNEL, "nvme%dq%d", nr, nvmeq->qid);
> > + if (!devname)
> > + return -ENOMEM;
> > +
> > + mask = pci_irq_get_affinity(pdev, nvmeq->cq_vector);
> > + if (mask && cpumask_weight(mask) > 1)
> > + irqflags |= IRQF_RESCUE_THREAD;
> > +
> > + return request_threaded_irq(vector, nvme_irq, NULL, irqflags,
> > + devname, nvmeq);
>
> This will leak 'devname' which gets allocated by kasprintf() a few lines
> above.

It won't, please see pci_free_irq() in which free_irq() returns the
'devname' passed in.

Thanks,
Ming