Re: [PATCH v2 1/2] pl031: Use timer_free() in the finalize function to avoid memleaks

[Peter Maydell]

On Tue, 12 Jan 2021 at 10:20, Gan Qixin <ganqixin@huawei.com> wrote:
>
> When running device-introspect-test, a memory leak occurred in the pl031_init
> function, this patch use timer_free() in the finalize function to fix it.
>
> ASAN shows memory leak stack:
>
> Direct leak of 48 byte(s) in 1 object(s) allocated from:
>     #0 0xffffab97e1f0 in __interceptor_calloc (/lib64/libasan.so.5+0xee1f0)
>     #1 0xffffab256800 in g_malloc0 (/lib64/libglib-2.0.so.0+0x56800)
>     #2 0xaaabf5621cfc in timer_new_full qemu/include/qemu/timer.h:523
>     #3 0xaaabf5621cfc in timer_new qemu/include/qemu/timer.h:544
>     #4 0xaaabf5621cfc in timer_new_ns qemu/include/qemu/timer.h:562
>     #5 0xaaabf5621cfc in pl031_init qemu/hw/rtc/pl031.c:194
>     #6 0xaaabf6339f6c in object_initialize_with_type qemu/qom/object.c:515
>     #7 0xaaabf633a1e0 in object_new_with_type qemu/qom/object.c:729
>     #8 0xaaabf6375e40 in qmp_device_list_properties 
> qemu/qom/qom-qmp-cmds.c:153
>     #9 0xaaabf5a95540 in qdev_device_help qemu/softmmu/qdev-monitor.c:283
>     #10 0xaaabf5a96940 in qmp_device_add qemu/softmmu/qdev-monitor.c:801
>     #11 0xaaabf5a96e70 in hmp_device_add qemu/softmmu/qdev-monitor.c:916
>     #12 0xaaabf5ac0a2c in handle_hmp_command qemu/monitor/hmp.c:1100
>
> Reported-by: Euler Robot <euler.robot@huawei.com>
> Signed-off-by: Gan Qixin <ganqixin@huawei.com>
> ---
> Cc: Peter Maydell <peter.maydell@linaro.org>
> ---
>  hw/rtc/pl031.c | 9 +++++++++
>  1 file changed, 9 insertions(+)
>
> diff --git a/hw/rtc/pl031.c b/hw/rtc/pl031.c
> index ae47f09635..f0981e6c21 100644
> --- a/hw/rtc/pl031.c
> +++ b/hw/rtc/pl031.c
> @@ -194,6 +194,14 @@ static void pl031_init(Object *obj)
>      s->timer = timer_new_ns(rtc_clock, pl031_interrupt, s);
>  }
>
> +static void pl031_finalize(Object *obj)
> +{
> +    PL031State *s = PL031(obj);
> +
> +    timer_del(s->timer);
> +    timer_free(s->timer);

You don't need to call timer_del() before timer_free() any more:
see commit 5f8e93c3e262ab.

thanks
-- PMM