Re: [PATCH v2 2/2] hw: move timer_new from init() into realize() to avoid memleaks

[Peter Maydell <peter.maydell@linaro.org>]

On Mon, 17 Feb 2020 at 03:22, <pannengyuan@huawei.com> wrote:
>
> From: Pan Nengyuan <pannengyuan@huawei.com>
>
> There are some memleaks when we call 'device_list_properties'. This patch move timer_new from init into realize to fix it.
> Meanwhile, do the null check in mos6522_reset() to avoid null deref if we move timer_new into realize().
>
> Reported-by: Euler Robot <euler.robot@huawei.com>
> Signed-off-by: Pan Nengyuan <pannengyuan@huawei.com>
> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>


> diff --git a/hw/misc/mos6522.c b/hw/misc/mos6522.c
> index 19e154b870..980eda7599 100644
> --- a/hw/misc/mos6522.c
> +++ b/hw/misc/mos6522.c
> @@ -465,11 +465,15 @@ static void mos6522_reset(DeviceState *dev)
>      s->timers[0].frequency = s->frequency;
>      s->timers[0].latch = 0xffff;
>      set_counter(s, &s->timers[0], 0xffff);
> -    timer_del(s->timers[0].timer);
> +    if (s->timers[0].timer) {
> +        timer_del(s->timers[0].timer);
> +    }
>
>      s->timers[1].frequency = s->frequency;
>      s->timers[1].latch = 0xffff;
> -    timer_del(s->timers[1].timer);
> +    if (s->timers[1].timer) {
> +        timer_del(s->timers[1].timer);
> +    }
>  }

What code path calls a device 'reset' method on a device
that has not yet been realized ? I wasn't expecting that
to be valid...

thanks
-- PMM