Re: [Qemu-devel] [PATCH for-2.4] watchdog/diag288: correctly register for system reset requests

[Peter Crosthwaite]

On Tue, Jul 7, 2015 at 1:53 AM, Cornelia Huck <address@hidden> wrote:
> From: Xu Wang <address@hidden>
>
> The diag288 watchdog is no sysbus device, therefore it doesn't get
> triggered on resets automatically using dc->reset.
>
> Let's register the reset handler manually, so we get correctly notified
> again when a system reset was requested. Also reset the watchdog on
> subsystem resets that don't trigger a full system reset.
>
> Signed-off-by: Xu Wang <address@hidden>
> Reviewed-by: David Hildenbrand <address@hidden>
> Signed-off-by: Cornelia Huck <address@hidden>
> ---
>  hw/s390x/s390-virtio-ccw.c | 6 +++++-
>  hw/watchdog/wdt_diag288.c  | 8 ++++++++
>  2 files changed, 13 insertions(+), 1 deletion(-)
>
> diff --git a/hw/s390x/s390-virtio-ccw.c b/hw/s390x/s390-virtio-ccw.c
> index 3d20d6a..4c51d1a 100644
> --- a/hw/s390x/s390-virtio-ccw.c
> +++ b/hw/s390x/s390-virtio-ccw.c
> @@ -36,7 +36,7 @@ typedef struct S390CcwMachineState {
>
>  void io_subsystem_reset(void)
>  {
> -    DeviceState *css, *sclp, *flic;
> +    DeviceState *css, *sclp, *flic, *diag288;
>
>      css = DEVICE(object_resolve_path_type("", "virtual-css-bridge", NULL));
>      if (css) {
> @@ -51,6 +51,10 @@ void io_subsystem_reset(void)
>      if (flic) {
>          qdev_reset_all(flic);
>      }
> +    diag288 = DEVICE(object_resolve_path_type("", "diag288", NULL));
> +    if (diag288) {
> +        qdev_reset_all(diag288);
> +    }
>  }
>
>  static int virtio_ccw_hcall_notify(const uint64_t *args)
> diff --git a/hw/watchdog/wdt_diag288.c b/hw/watchdog/wdt_diag288.c
> index 1185e06..2a885a4 100644
> --- a/hw/watchdog/wdt_diag288.c
> +++ b/hw/watchdog/wdt_diag288.c
> @@ -40,6 +40,13 @@ static void wdt_diag288_reset(DeviceState *dev)
>      timer_del(diag288->timer);
>  }
>
> +static void diag288_reset(void *opaque)
> +{
> +    DeviceState *diag288 = opaque;
> +
> +    wdt_diag288_reset(diag288);
> +}
> +
>  static void diag288_timer_expired(void *dev)
>  {
>      qemu_log_mask(CPU_LOG_RESET, "Watchdog timer expired.\n");
> @@ -80,6 +87,7 @@ static void wdt_diag288_realize(DeviceState *dev, Error 
> **errp)
>  {
>      DIAG288State *diag288 = DIAG288(dev);
>
> +    qemu_register_reset(diag288_reset, diag288);

Doesn't seem right. Even if it is not a SBD it should still sit in the
QOM tree in a place where the reset is reached. Where is this device
in the QOM tree?

I.E. What string do you get with an object_get_canonical_path() of the
obj after machine init?

Regards,
Peter

>      diag288->timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, diag288_timer_expired,
>                                    dev);
>  }
> --
> 2.4.5
>
>