[PATCH 2/3] hw/char/serial-pci-multi: Use qemu_init_irq_child() to avoid leak

[Peter Maydell]

The serial-pci-multi device initializes an IRQ with qemu_init_irq()
in its instance_init function; however it never calls qemu_free_irq(),
so the init/deinit cycle has a memory leak, which ASAN catches
in the device-introspect-test:

Direct leak of 576 byte(s) in 6 object(s) allocated from:
    #0 0x626306ddade3 in malloc 
(/mnt/nvmedisk/linaro/qemu-from-laptop/qemu/build/arm-asan/qem
u-system-arm+0x21f1de3) (BuildId: 52ece17287eba2d68e5be980e1856cd1f6be932f)
    #1 0x7756ade79b09 in g_malloc 
(/lib/x86_64-linux-gnu/libglib-2.0.so.0+0x62b09) (BuildId: 1
eb6131419edb83b2178b682829a6913cf682d75)
    #2 0x7756ade5b45a in g_hash_table_new_full 
(/lib/x86_64-linux-gnu/libglib-2.0.so.0+0x4445a
) (BuildId: 1eb6131419edb83b2178b682829a6913cf682d75)
    #3 0x62630965da37 in object_initialize_with_type 
/mnt/nvmedisk/linaro/qemu-from-laptop/qem
u/build/arm-asan/../../qom/object.c:568:23
    #4 0x62630965d440 in object_initialize 
/mnt/nvmedisk/linaro/qemu-from-laptop/qemu/build/ar
m-asan/../../qom/object.c:578:5
    #5 0x626309653eeb in qemu_init_irq 
/mnt/nvmedisk/linaro/qemu-from-laptop/qemu/build/arm-as
an/../../hw/core/irq.c:48:5
    #6 0x6263072370bb in multi_serial_init 
/mnt/nvmedisk/linaro/qemu-from-laptop/qemu/build/arm-asan/../../hw/char/serial-pci-multi.c:183:9

Use the new qemu_init_irq_child() function instead, so that the
IRQ object is automatically unreffed when the serial-pci
device is deinited.

Signed-off-by: Peter Maydell <peter.mayd...@linaro.org>
---
 hw/char/serial-pci-multi.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/hw/char/serial-pci-multi.c b/hw/char/serial-pci-multi.c
index 13df272691a..9410428ba90 100644
--- a/hw/char/serial-pci-multi.c
+++ b/hw/char/serial-pci-multi.c
@@ -180,7 +180,9 @@ static void multi_serial_init(Object *o)
     size_t i, nports = multi_serial_get_port_count(PCI_DEVICE_GET_CLASS(dev));
 
     for (i = 0; i < nports; i++) {
-        qemu_init_irq(&pms->irqs[i], multi_serial_irq_mux, pms, i);
+        g_autofree char *irqpropname = g_strdup_printf("irq[%zu]", i);
+        qemu_init_irq_child(o, irqpropname, &pms->irqs[i],
+                            multi_serial_irq_mux, pms, i);
         object_initialize_child(o, "serial[*]", &pms->state[i], TYPE_SERIAL);
     }
 }
-- 
2.43.0