drm: logicvc: add of_node_put() and switch to a more secure approach

[PATCH 2/3] drm: logicvc: switch to for_each_child_of_node_scoped()

Posted by Javier Carrasco 1 month, 2 weeks ago

Use the scoped variant of the macro to avoid leaking memory upon early
exits without the required call to of_node_put().

Signed-off-by: Javier Carrasco <javier.carrasco.cruz@gmail.com>
---
 drivers/gpu/drm/logicvc/logicvc_layer.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/logicvc/logicvc_layer.c b/drivers/gpu/drm/logicvc/logicvc_layer.c
index 52dabacd42ee..34caf5f0f619 100644
--- a/drivers/gpu/drm/logicvc/logicvc_layer.c
+++ b/drivers/gpu/drm/logicvc/logicvc_layer.c
@@ -581,7 +581,6 @@ int logicvc_layers_init(struct logicvc_drm *logicvc)
 	struct drm_device *drm_dev = &logicvc->drm_dev;
 	struct device *dev = drm_dev->dev;
 	struct device_node *of_node = dev->of_node;
-	struct device_node *layer_node = NULL;
 	struct device_node *layers_node;
 	struct logicvc_layer *layer;
 	struct logicvc_layer *next;
@@ -594,7 +593,7 @@ int logicvc_layers_init(struct logicvc_drm *logicvc)
 		goto error;
 	}
 
-	for_each_child_of_node(layers_node, layer_node) {
+	for_each_child_of_node_scoped(layers_node, layer_node) {
 		u32 index = 0;
 
 		if (!logicvc_of_node_is_layer(layer_node))
@@ -613,7 +612,6 @@ int logicvc_layers_init(struct logicvc_drm *logicvc)
 
 		ret = logicvc_layer_init(logicvc, layer_node, index);
 		if (ret) {
-			of_node_put(layer_node);
 			of_node_put(layers_node);
 			goto error;
 		}

-- 
2.43.0

Re: [PATCH 2/3] drm: logicvc: switch to for_each_child_of_node_scoped()

Posted by Louis Chauvet 1 month, 2 weeks ago

Hi,

I think you can squash this commit with the prvious one, I don't think 
this is needed to add of_node_put and remove it just after.

Thanks,
Louis Chauvet

On 11/10/24 - 01:11, Javier Carrasco wrote:
> Use the scoped variant of the macro to avoid leaking memory upon early
> exits without the required call to of_node_put().
> 
> Signed-off-by: Javier Carrasco <javier.carrasco.cruz@gmail.com>
> ---
>  drivers/gpu/drm/logicvc/logicvc_layer.c | 4 +---
>  1 file changed, 1 insertion(+), 3 deletions(-)
> 
> diff --git a/drivers/gpu/drm/logicvc/logicvc_layer.c b/drivers/gpu/drm/logicvc/logicvc_layer.c
> index 52dabacd42ee..34caf5f0f619 100644
> --- a/drivers/gpu/drm/logicvc/logicvc_layer.c
> +++ b/drivers/gpu/drm/logicvc/logicvc_layer.c
> @@ -581,7 +581,6 @@ int logicvc_layers_init(struct logicvc_drm *logicvc)
>  	struct drm_device *drm_dev = &logicvc->drm_dev;
>  	struct device *dev = drm_dev->dev;
>  	struct device_node *of_node = dev->of_node;
> -	struct device_node *layer_node = NULL;
>  	struct device_node *layers_node;
>  	struct logicvc_layer *layer;
>  	struct logicvc_layer *next;
> @@ -594,7 +593,7 @@ int logicvc_layers_init(struct logicvc_drm *logicvc)
>  		goto error;
>  	}
>  
> -	for_each_child_of_node(layers_node, layer_node) {
> +	for_each_child_of_node_scoped(layers_node, layer_node) {
>  		u32 index = 0;
>  
>  		if (!logicvc_of_node_is_layer(layer_node))
> @@ -613,7 +612,6 @@ int logicvc_layers_init(struct logicvc_drm *logicvc)
>  
>  		ret = logicvc_layer_init(logicvc, layer_node, index);
>  		if (ret) {
> -			of_node_put(layer_node);
>  			of_node_put(layers_node);
>  			goto error;
>  		}
> 
> -- 
> 2.43.0
>

Re: [PATCH 2/3] drm: logicvc: switch to for_each_child_of_node_scoped()

Posted by Louis Chauvet 1 month, 2 weeks ago

On 11/10/24 - 15:01, Louis Chauvet wrote:
> Hi,
> 
> I think you can squash this commit with the prvious one, I don't think 
> this is needed to add of_node_put and remove it just after.

Forget this, I missed the Fixes in the first commit, sorry for the noise.

Reviewed-by: Louis Chauvet <louis.chauvet@bootlin.com>

> Thanks,
> Louis Chauvet
> 
> On 11/10/24 - 01:11, Javier Carrasco wrote:
> > Use the scoped variant of the macro to avoid leaking memory upon early
> > exits without the required call to of_node_put().
> > 
> > Signed-off-by: Javier Carrasco <javier.carrasco.cruz@gmail.com>
> > ---
> >  drivers/gpu/drm/logicvc/logicvc_layer.c | 4 +---
> >  1 file changed, 1 insertion(+), 3 deletions(-)
> > 
> > diff --git a/drivers/gpu/drm/logicvc/logicvc_layer.c b/drivers/gpu/drm/logicvc/logicvc_layer.c
> > index 52dabacd42ee..34caf5f0f619 100644
> > --- a/drivers/gpu/drm/logicvc/logicvc_layer.c
> > +++ b/drivers/gpu/drm/logicvc/logicvc_layer.c
> > @@ -581,7 +581,6 @@ int logicvc_layers_init(struct logicvc_drm *logicvc)
> >  	struct drm_device *drm_dev = &logicvc->drm_dev;
> >  	struct device *dev = drm_dev->dev;
> >  	struct device_node *of_node = dev->of_node;
> > -	struct device_node *layer_node = NULL;
> >  	struct device_node *layers_node;
> >  	struct logicvc_layer *layer;
> >  	struct logicvc_layer *next;
> > @@ -594,7 +593,7 @@ int logicvc_layers_init(struct logicvc_drm *logicvc)
> >  		goto error;
> >  	}
> >  
> > -	for_each_child_of_node(layers_node, layer_node) {
> > +	for_each_child_of_node_scoped(layers_node, layer_node) {
> >  		u32 index = 0;
> >  
> >  		if (!logicvc_of_node_is_layer(layer_node))
> > @@ -613,7 +612,6 @@ int logicvc_layers_init(struct logicvc_drm *logicvc)
> >  
> >  		ret = logicvc_layer_init(logicvc, layer_node, index);
> >  		if (ret) {
> > -			of_node_put(layer_node);
> >  			of_node_put(layers_node);
> >  			goto error;
> >  		}
> > 
> > -- 
> > 2.43.0
> >

Re: [PATCH 2/3] drm: logicvc: switch to for_each_child_of_node_scoped()

Posted by Javier Carrasco 1 month, 2 weeks ago

On 11/10/2024 15:01, Louis Chauvet wrote:
> Hi,
> 
> I think you can squash this commit with the prvious one, I don't think 
> this is needed to add of_node_put and remove it just after.
> 
> Thanks,
> Louis Chauvet
> 

Hi Louis,

Thanks for your review. I did not squash them because the first one
would apply to stable patches (note the Cc: tag) that are older than the
scoped macro, which was introduced this year.

Best regards,
Javier Carrasco