Re: [PATCH 3/3] drm/meson: add missing of_node_put

From: Neil Armstrong
Date: Mon Jan 14 2019 - 10:33:05 EST


Hi Julia,

On 13/01/2019 10:44, Julia Lawall wrote:
> Add an of_node_put when the result of of_graph_get_remote_port_parent is
> not available.
>
> An of_node_put is also needed when meson_probe_remote completes. This was
> present at the recursive call, but not in the call from meson_drv_probe.
>
> The semantic match that finds this problem is as follows
> (http://coccinelle.lip6.fr):
>
> // <smpl>
> @r exists@
> local idexpression e;
> expression x;
> @@
> e = of_graph_get_remote_port_parent(...);
> ... when != x = e
> when != true e == NULL
> when != of_node_put(e)
> when != of_fwnode_handle(e)
> (
> return e;
> |
> *return ...;
> )
> // </smpl>
>
> Signed-off-by: Julia Lawall <Julia.Lawall@xxxxxxx>

Acked-by: Neil Armstrong <narmstrong@xxxxxxxxxxxx>

And applied to drm-misc-fixes.

Neil

>
> ---
> drivers/gpu/drm/meson/meson_drv.c | 9 +++++++--
> 1 file changed, 7 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/meson/meson_drv.c b/drivers/gpu/drm/meson/meson_drv.c
> index 3ee4d4a4e..b59c757 100644
> --- a/drivers/gpu/drm/meson/meson_drv.c
> +++ b/drivers/gpu/drm/meson/meson_drv.c
> @@ -388,8 +388,10 @@ static int meson_probe_remote(struct platform_device *pdev,
> remote_node = of_graph_get_remote_port_parent(ep);
> if (!remote_node ||
> remote_node == parent || /* Ignore parent endpoint */
> - !of_device_is_available(remote_node))
> + !of_device_is_available(remote_node)) {
> + of_node_put(remote_node);
> continue;
> + }
>
> count += meson_probe_remote(pdev, match, remote, remote_node);
>
> @@ -408,10 +410,13 @@ static int meson_drv_probe(struct platform_device *pdev)
>
> for_each_endpoint_of_node(np, ep) {
> remote = of_graph_get_remote_port_parent(ep);
> - if (!remote || !of_device_is_available(remote))
> + if (!remote || !of_device_is_available(remote)) {
> + of_node_put(remote);
> continue;
> + }
>
> count += meson_probe_remote(pdev, &match, np, remote);
> + of_node_put(remote);
> }
>
> if (count && !match)
>