The qemu_init_irq() method initializes an IRQ object, but
the caller is responsible for eventually freeing it by calling
qemu_free_irq(). Generally we don't remember to do this.

Implement a harder-to-misuse API, qemu_init_irq_child().  This is to
qemu_init_irq() what object_initialize_child() is to
object_initialize(): it both initializes the object and makes it a
child of the parent QOM object.  If you use this in a device's
realize or instance_init method then the IRQ will be automatically
freed when the device is destroyed.

Patch 1 is the new function; patches 2 and 3 are bugfixes for
leaks that show up with ASAN in device-introspect-test (which
does an instance_init -> deinit on every device).

The other callers of qemu_init_irq() could also be changed over
to use this new function, but they don't cause in-practice
leaks because they call the function in realize, and they
are devices which are never unrealized.

thanks
-- PMM

Peter Maydell (3):
  hw/irq: New qemu_init_irq_child() function
  hw/char/serial-pci-multi: Use qemu_init_irq_child() to avoid leak
  hw/ide/ich.c: Use qemu_init_irq_child() to avoid memory leak

 include/hw/irq.h           | 23 ++++++++++++++++++++++-
 hw/char/serial-pci-multi.c |  4 +++-
 hw/core/irq.c              |  8 ++++++++
 hw/ide/ich.c               |  3 ++-
 4 files changed, 35 insertions(+), 3 deletions(-)

-- 
2.43.0

On 21/8/25 17:40, Peter Maydell wrote:
> The qemu_init_irq() method initializes an IRQ object, but
> the caller is responsible for eventually freeing it by calling
> qemu_free_irq(). Generally we don't remember to do this.
> 
> Implement a harder-to-misuse API, qemu_init_irq_child().  This is to
> qemu_init_irq() what object_initialize_child() is to
> object_initialize(): it both initializes the object and makes it a
> child of the parent QOM object.  If you use this in a device's
> realize or instance_init method then the IRQ will be automatically
> freed when the device is destroyed.
> 
> Patch 1 is the new function; patches 2 and 3 are bugfixes for
> leaks that show up with ASAN in device-introspect-test (which
> does an instance_init -> deinit on every device).
> 
> The other callers of qemu_init_irq() could also be changed over
> to use this new function, but they don't cause in-practice
> leaks because they call the function in realize, and they
> are devices which are never unrealized.

There are only 4 uses left. I don't see any good reason to keep
qemu_init_irq() over qemu_init_irq_child(). Maybe better fully
remove the former by the latter?

> Peter Maydell (3):
>    hw/irq: New qemu_init_irq_child() function
>    hw/char/serial-pci-multi: Use qemu_init_irq_child() to avoid leak
>    hw/ide/ich.c: Use qemu_init_irq_child() to avoid memory leak

Series queued, thanks!