Re: [PATCH 6/6] hw/isa/piix4: Fix leak removing unuseful qemu_allocate_irqs() call

[Philippe Mathieu-Daudé]

ping for review?

On 3/24/21 12:13 AM, Philippe Mathieu-Daudé wrote:
> We locally create an input IRQ with qemu_allocate_irqs() to
> pass it as output IRQ of the PIC, but its handler simply dispatch
> into another of our output IRQ ("intr" output).
> 
> Simplify by directly connecting the PIC output to our "intr"
> output.
> 
> This fixes when using QEMU built with --enable-sanitizers:
> 
>   ==338425==ERROR: LeakSanitizer: detected memory leaks
> 
>   Direct leak of 8 byte(s) in 1 object(s) allocated from:
>     #0 0x5641b361e1df in malloc (qemu-system-mips+0x1b201df)
>     #1 0x7f995e683958 in g_malloc (/lib64/libglib-2.0.so.0+0x58958)
>     #2 0x5641b5558e36 in qemu_allocate_irqs hw/core/irq.c:66:12
>     #3 0x5641b4161817 in piix4_realize hw/isa/piix4.c:171:21
>     #4 0x5641b42f077a in pci_qdev_realize hw/pci/pci.c:2114:9
>     #5 0x5641b554c802 in device_set_realized hw/core/qdev.c:761:13
>     #6 0x5641b5578458 in property_set_bool qom/object.c:2257:5
>     #7 0x5641b55709e2 in object_property_set qom/object.c:1402:5
>     #8 0x5641b55861c9 in object_property_set_qobject qom/qom-qobject.c:28:10
>     #9 0x5641b5571831 in object_property_set_bool qom/object.c:1472:15
>    #10 0x5641b55410fd in qdev_realize hw/core/qdev.c:389:12
> 
> Fixes: 078778c5a55 ("piix4: Add an i8259 Interrupt Controller as specified in 
> datasheet")
> Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
> ---
>  hw/isa/piix4.c | 10 +---------
>  1 file changed, 1 insertion(+), 9 deletions(-)
> 
> diff --git a/hw/isa/piix4.c b/hw/isa/piix4.c
> index a50d97834c7..79ed20e2a1a 100644
> --- a/hw/isa/piix4.c
> +++ b/hw/isa/piix4.c
> @@ -103,12 +103,6 @@ static const VMStateDescription vmstate_piix4 = {
>      }
>  };
>  
> -static void piix4_request_i8259_irq(void *opaque, int irq, int level)
> -{
> -    PIIX4State *s = opaque;
> -    qemu_set_irq(s->cpu_intr, level);
> -}
> -
>  static void piix4_set_i8259_irq(void *opaque, int irq, int level)
>  {
>      PIIX4State *s = opaque;
> @@ -149,7 +143,6 @@ static void piix4_realize(PCIDevice *dev, Error **errp)
>  {
>      PIIX4State *s = PIIX4_PCI_DEVICE(dev);
>      ISABus *isa_bus;
> -    qemu_irq *i8259_out_irq;
>  
>      isa_bus = isa_bus_new(DEVICE(dev), pci_address_space(dev),
>                            pci_address_space_io(dev), errp);
> @@ -168,8 +161,7 @@ static void piix4_realize(PCIDevice *dev, Error **errp)
>                                          PIIX_RCR_IOPORT, &s->rcr_mem, 1);
>  
>      /* initialize i8259 pic */
> -    i8259_out_irq = qemu_allocate_irqs(piix4_request_i8259_irq, s, 1);
> -    s->isa = i8259_init(isa_bus, *i8259_out_irq);
> +    s->isa = i8259_init(isa_bus, s->cpu_intr);
>  
>      /* initialize ISA irqs */
>      isa_bus_irqs(isa_bus, s->isa);
>