Re: [PATCH] hw/ide/sii3112: Use qdev gpio rather than qemu_allocate_irqs()

[BALATON Zoltan]

On Mon, 23 Mar 2020, Peter Maydell wrote:
> Coverity points out (CID 1421984) that we are leaking the
> memory returned by qemu_allocate_irqs(). We can avoid this
> leak by switching to using qdev_init_gpio_in(); the base
> class finalize will free the irqs that this allocates under
> the hood.
>
> Signed-off-by: Peter Maydell <address@hidden>
> ---
> This is how the 'use qdev gpio' approach to fixing the leak looks.
> Disclaimer: I have only tested this with "make check", nothing more.
>
> hw/ide/sii3112.c | 6 +++---
> 1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/hw/ide/sii3112.c b/hw/ide/sii3112.c
> index 06605d7af2b..2ae6f5d9df6 100644
> --- a/hw/ide/sii3112.c
> +++ b/hw/ide/sii3112.c
> @@ -251,8 +251,8 @@ static void sii3112_pci_realize(PCIDevice *dev, Error 
> **errp)
> {
>     SiI3112PCIState *d = SII3112_PCI(dev);
>     PCIIDEState *s = PCI_IDE(dev);
> +    DeviceState *ds = DEVICE(dev);
>     MemoryRegion *mr;
> -    qemu_irq *irq;
>     int i;
>
>     pci_config_set_interrupt_pin(dev->config, 1);
> @@ -280,10 +280,10 @@ static void sii3112_pci_realize(PCIDevice *dev, Error 
> **errp)
>     memory_region_init_alias(mr, OBJECT(d), "sii3112.bar4", &d->mmio, 0, 16);
>     pci_register_bar(dev, 4, PCI_BASE_ADDRESS_SPACE_IO, mr);
>
> -    irq = qemu_allocate_irqs(sii3112_set_irq, d, 2);
> +    qdev_init_gpio_in(ds, sii3112_set_irq, 2);
>     for (i = 0; i < 2; i++) {
>         ide_bus_new(&s->bus[i], sizeof(s->bus[i]), DEVICE(dev), i, 1);
> -        ide_init2(&s->bus[i], irq[i]);
> +        ide_init2(&s->bus[i], qdev_get_gpio_in(ds, i));

Maybe we could just use DEVICE(dev) here and above as well just like in 
ide_bus_new above just to keep it consistent and avoid the confusion 
caused by having dev, d, s and now also ds. DEVICE(dev) is short and clear 
enough I think.

Regards,
BALATON Zoltan

>         bmdma_init(&s->bus[i], &s->bmdma[i], s);
>         s->bmdma[i].bus = &s->bus[i];