Re: [PATCH] media: v4l2-async: Put fwnode after last access

From: Laurent Pinchart
Date: Mon Dec 28 2020 - 11:16:37 EST


Hi Ezequiel,

Thank you for the patch.

On Mon, Dec 28, 2020 at 09:17:25AM -0300, Ezequiel Garcia wrote:
> fwnode_handle_put() should be called after the fwnode
> is last accessed. Fix it.
>
> Fixes: b98158d837ef ("media: v4l2-async: Accept endpoints and devices for fwnode matching")
> Signed-off-by: Ezequiel Garcia <ezequiel@xxxxxxxxxxxxx>
> ---
> drivers/media/v4l2-core/v4l2-async.c | 6 ++++--
> 1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/media/v4l2-core/v4l2-async.c b/drivers/media/v4l2-core/v4l2-async.c
> index e3ab003a6c85..1303c9b83138 100644
> --- a/drivers/media/v4l2-core/v4l2-async.c
> +++ b/drivers/media/v4l2-core/v4l2-async.c
> @@ -78,6 +78,7 @@ static bool match_fwnode(struct v4l2_async_notifier *notifier,
> bool asd_fwnode_is_ep;
> bool sd_fwnode_is_ep;
> struct device *dev;
> + bool match;
>
> /*
> * Both the subdev and the async subdev can provide either an endpoint
> @@ -113,9 +114,10 @@ static bool match_fwnode(struct v4l2_async_notifier *notifier,
> other_fwnode = sd->fwnode;
> }
>
> - fwnode_handle_put(dev_fwnode);
> + match = (dev_fwnode == other_fwnode);
>
> - if (dev_fwnode != other_fwnode)

This only performs a pointer comparison, it doesn't access dev_fwnode. I
don't think the change is necessary.

> + fwnode_handle_put(dev_fwnode);
> + if (!match)
> return false;
>
> /*

--
Regards,

Laurent Pinchart