Re: [PATCH] drm/nouveau/dispnv50: fix runtime pm imbalance on error

From: Lyude Paul
Date: Wed Jun 03 2020 - 12:26:22 EST


Hi! Was going through my email and found this from last month, it's a bit late
and someone might have reviewed/pushed this already but just in case:

Reviewed-by: Lyude Paul <lyude@xxxxxxxxxx>

On Wed, 2020-05-20 at 18:47 +0800, Dinghao Liu wrote:
> pm_runtime_get_sync() increments the runtime PM usage counter even
> the call returns an error code. Thus a pairing decrement is needed
> on the error handling path to keep the counter balanced.
>
> Signed-off-by: Dinghao Liu <dinghao.liu@xxxxxxxxxx>
> ---
> drivers/gpu/drm/nouveau/dispnv50/disp.c | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/nouveau/dispnv50/disp.c
> b/drivers/gpu/drm/nouveau/dispnv50/disp.c
> index 6be9df1820c5..e670756664ff 100644
> --- a/drivers/gpu/drm/nouveau/dispnv50/disp.c
> +++ b/drivers/gpu/drm/nouveau/dispnv50/disp.c
> @@ -1123,8 +1123,10 @@ nv50_mstc_detect(struct drm_connector *connector,
> return connector_status_disconnected;
>
> ret = pm_runtime_get_sync(connector->dev->dev);
> - if (ret < 0 && ret != -EACCES)
> + if (ret < 0 && ret != -EACCES) {
> + pm_runtime_put_autosuspend(connector->dev->dev);
> return connector_status_disconnected;
> + }
>
> ret = drm_dp_mst_detect_port(connector, ctx, mstc->port->mgr,
> mstc->port);