Hi Christophe,
On Tue, Jun 13, 2023 at 07:15:40PM +0200, Christophe JAILLET wrote:
> Le 13/06/2023 à 12:55, Sakari Ailus a écrit :
> > Hi Christophe,
> >
> > On Mon, May 29, 2023 at 08:17:18AM +0200, Christophe JAILLET wrote:
> > > 'fwnode is known to be NULL, at this point, so fwnode_handle_put() is a
> > > no-op.
> > >
> > > Release the reference taken from a previous fwnode_graph_get_port_parent()
> > > call instead.
> > >
> > > Fixes: ca50c197bd96 ("[media] v4l: fwnode: Support generic fwnode for parsing standardised properties")
> > > Signed-off-by: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx>
> > > ---
> > > /!\ THIS PATCH IS SPECULATIVE /!\
> > > review with care
> > > ---
> > > drivers/media/v4l2-core/v4l2-fwnode.c | 2 +-
> > > 1 file changed, 1 insertion(+), 1 deletion(-)
> > >
> > > diff --git a/drivers/media/v4l2-core/v4l2-fwnode.c b/drivers/media/v4l2-core/v4l2-fwnode.c
> > > index 049c2f2001ea..b7dd467c53fd 100644
> > > --- a/drivers/media/v4l2-core/v4l2-fwnode.c
> > > +++ b/drivers/media/v4l2-core/v4l2-fwnode.c
> > > @@ -571,7 +571,7 @@ int v4l2_fwnode_parse_link(struct fwnode_handle *fwnode,
> > > fwnode = fwnode_graph_get_remote_endpoint(fwnode);
> > > if (!fwnode) {
> > > - fwnode_handle_put(fwnode);
> > > + fwnode_handle_put(link->local_node);
> >
> > link->local_node also needs to be non-NULL for the successful case. The
> > condition should take that into account. Could you send v2 with that?
> >
> > > return -ENOLINK;
> > > }
> >
>
> Hi,
> something like below?
Ah, remote_node must be non-NULL, too, indeed. It was surprisingly broken.
>
> @@ -568,19 +568,25 @@ int v4l2_fwnode_parse_link(struct fwnode_handle
> *fwnode,
> link->local_id = fwep.id;
> link->local_port = fwep.port;
> link->local_node = fwnode_graph_get_port_parent(fwnode);
> + if (!link->local_node)
> + return -ENOLINK;
>
> fwnode = fwnode_graph_get_remote_endpoint(fwnode);
> - if (!fwnode) {
> - fwnode_handle_put(fwnode);
> - return -ENOLINK;
> - }
> + if (!fwnode)
> + goto err_put_local_node;
On error, fwnode needs to be put from this onwards, too.
But you can use a single label: fwnode_handle_put() is NULL-safe.
>
> fwnode_graph_parse_endpoint(fwnode, &fwep);
> link->remote_id = fwep.id;
> link->remote_port = fwep.port;
> link->remote_node = fwnode_graph_get_port_parent(fwnode);
> + if (!link->remote_node)
> + goto err_put_local_node;
>
> return 0;
> +
> +err_put_local_node:
> + fwnode_handle_put(link->local_node);
> + return -ENOLINK;
> }
> EXPORT_SYMBOL_GPL(v4l2_fwnode_parse_link);
--
Kind regards,
Sakari Ailus
