of_graph_get_remote_node() returns remote device node pointer with
refcount incremented, we should use of_node_put() on it
when not need anymore.
Add missing of_node_put() to avoid refcount leak.
Fixes: 86418f90a4c1 ("drm: convert drivers to use of_graph_get_remote_node")
Signed-off-by: Miaoqian Lin <[email protected]>
---
drivers/gpu/drm/msm/disp/mdp4/mdp4_kms.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/drivers/gpu/drm/msm/disp/mdp4/mdp4_kms.c b/drivers/gpu/drm/msm/disp/mdp4/mdp4_kms.c
index fb48c8c19ec3..17cb1fc78379 100644
--- a/drivers/gpu/drm/msm/disp/mdp4/mdp4_kms.c
+++ b/drivers/gpu/drm/msm/disp/mdp4/mdp4_kms.c
@@ -216,6 +216,7 @@ static int mdp4_modeset_init_intf(struct mdp4_kms *mdp4_kms,
encoder = mdp4_lcdc_encoder_init(dev, panel_node);
if (IS_ERR(encoder)) {
DRM_DEV_ERROR(dev->dev, "failed to construct LCDC encoder\n");
+ of_node_put(panel_node);
return PTR_ERR(encoder);
}
@@ -225,6 +226,7 @@ static int mdp4_modeset_init_intf(struct mdp4_kms *mdp4_kms,
connector = mdp4_lvds_connector_init(dev, panel_node, encoder);
if (IS_ERR(connector)) {
DRM_DEV_ERROR(dev->dev, "failed to initialize LVDS connector\n");
+ of_node_put(panel_node);
return PTR_ERR(connector);
}
--
2.25.1
On Tue, 7 Jun 2022 at 14:08, Miaoqian Lin <[email protected]> wrote:
>
> of_graph_get_remote_node() returns remote device node pointer with
> refcount incremented, we should use of_node_put() on it
> when not need anymore.
> Add missing of_node_put() to avoid refcount leak.
>
> Fixes: 86418f90a4c1 ("drm: convert drivers to use of_graph_get_remote_node")
> Signed-off-by: Miaoqian Lin <[email protected]>
Reviewed-by: Dmitry Baryshkov <[email protected]>
--
With best wishes
Dmitry
Quoting Miaoqian Lin (2022-06-07 04:08:38)
> of_graph_get_remote_node() returns remote device node pointer with
> refcount incremented, we should use of_node_put() on it
> when not need anymore.
> Add missing of_node_put() to avoid refcount leak.
>
> Fixes: 86418f90a4c1 ("drm: convert drivers to use of_graph_get_remote_node")
> Signed-off-by: Miaoqian Lin <[email protected]>
> ---
Reviewed-by: Stephen Boyd <[email protected]>
On 6/7/2022 4:08 AM, Miaoqian Lin wrote:
> of_graph_get_remote_node() returns remote device node pointer with
> refcount incremented, we should use of_node_put() on it
> when not need anymore.
> Add missing of_node_put() to avoid refcount leak.
>
> Fixes: 86418f90a4c1 ("drm: convert drivers to use of_graph_get_remote_node")
> Signed-off-by: Miaoqian Lin <[email protected]>
> ---
> drivers/gpu/drm/msm/disp/mdp4/mdp4_kms.c | 2 ++
> 1 file changed, 2 insertions(+)
>
This patch itself looks fine and will cover the cases when there was an
error and we did not release the refcount.
But, even in the normal cases I am not finding where we are releasing
the refcount for the panel_node.
I dont see a of_node_put() on mdp4_lcdc_encoder->panel_node.
Am i missing something?
> diff --git a/drivers/gpu/drm/msm/disp/mdp4/mdp4_kms.c b/drivers/gpu/drm/msm/disp/mdp4/mdp4_kms.c
> index fb48c8c19ec3..17cb1fc78379 100644
> --- a/drivers/gpu/drm/msm/disp/mdp4/mdp4_kms.c
> +++ b/drivers/gpu/drm/msm/disp/mdp4/mdp4_kms.c
> @@ -216,6 +216,7 @@ static int mdp4_modeset_init_intf(struct mdp4_kms *mdp4_kms,
> encoder = mdp4_lcdc_encoder_init(dev, panel_node);
> if (IS_ERR(encoder)) {
> DRM_DEV_ERROR(dev->dev, "failed to construct LCDC encoder\n");
> + of_node_put(panel_node);
> return PTR_ERR(encoder);
> }
>
> @@ -225,6 +226,7 @@ static int mdp4_modeset_init_intf(struct mdp4_kms *mdp4_kms,
> connector = mdp4_lvds_connector_init(dev, panel_node, encoder);
> if (IS_ERR(connector)) {
> DRM_DEV_ERROR(dev->dev, "failed to initialize LVDS connector\n");
> + of_node_put(panel_node);
> return PTR_ERR(connector);
> }
>
On 14/06/2022 13:07, Miaoqian Lin wrote:
> Hi, Abhinav
>
> On 2022/6/11 7:20, Abhinav Kumar wrote:
>>
>>
>> On 6/7/2022 4:08 AM, Miaoqian Lin wrote:
>>> of_graph_get_remote_node() returns remote device node pointer with
>>> refcount incremented, we should use of_node_put() on it
>>> when not need anymore.
>>> Add missing of_node_put() to avoid refcount leak.
>>>
>>> Fixes: 86418f90a4c1 ("drm: convert drivers to use of_graph_get_remote_node")
>>> Signed-off-by: Miaoqian Lin <[email protected]>
>>> ---
>>> drivers/gpu/drm/msm/disp/mdp4/mdp4_kms.c | 2 ++
>>> 1 file changed, 2 insertions(+)
>>>
>>
>> This patch itself looks fine and will cover the cases when there was an error and we did not release the refcount.
>>
>> But, even in the normal cases I am not finding where we are releasing the refcount for the panel_node.
>>
>> I dont see a of_node_put() on mdp4_lcdc_encoder->panel_node.
>>
> Thanks for your review.
>
> I don't see it either. It's a bit messy because the reference assigned to mdp4_lcdc_encoder->panel_node and mdp4_lvds_connector->panel_node both.
I have a plan to rework mdp4 lcdc support once I get my ifc6410 lvds
cable. Thus I think we can land this patch now and fix the mdp4
lcdc/lvds code leaking the reference in the due time.
>
>> Am i missing something?
>>
>>> diff --git a/drivers/gpu/drm/msm/disp/mdp4/mdp4_kms.c b/drivers/gpu/drm/msm/disp/mdp4/mdp4_kms.c
>>> index fb48c8c19ec3..17cb1fc78379 100644
>>> --- a/drivers/gpu/drm/msm/disp/mdp4/mdp4_kms.c
>>> +++ b/drivers/gpu/drm/msm/disp/mdp4/mdp4_kms.c
>>> @@ -216,6 +216,7 @@ static int mdp4_modeset_init_intf(struct mdp4_kms *mdp4_kms,
>>> encoder = mdp4_lcdc_encoder_init(dev, panel_node);
>>> if (IS_ERR(encoder)) {
>>> DRM_DEV_ERROR(dev->dev, "failed to construct LCDC encoder\n");
>>> + of_node_put(panel_node);
>>> return PTR_ERR(encoder);
>>> }
>>> @@ -225,6 +226,7 @@ static int mdp4_modeset_init_intf(struct mdp4_kms *mdp4_kms,
>>> connector = mdp4_lvds_connector_init(dev, panel_node, encoder);
>>> if (IS_ERR(connector)) {
>>> DRM_DEV_ERROR(dev->dev, "failed to initialize LVDS connector\n");
>>> + of_node_put(panel_node);
>>> return PTR_ERR(connector);
>>> }
>>>
--
With best wishes
Dmitry
Hi, Abhinav
On 2022/6/11 7:20, Abhinav Kumar wrote:
>
>
> On 6/7/2022 4:08 AM, Miaoqian Lin wrote:
>> of_graph_get_remote_node() returns remote device node pointer with
>> refcount incremented, we should use of_node_put() on it
>> when not need anymore.
>> Add missing of_node_put() to avoid refcount leak.
>>
>> Fixes: 86418f90a4c1 ("drm: convert drivers to use of_graph_get_remote_node")
>> Signed-off-by: Miaoqian Lin <[email protected]>
>> ---
>> drivers/gpu/drm/msm/disp/mdp4/mdp4_kms.c | 2 ++
>> 1 file changed, 2 insertions(+)
>>
>
> This patch itself looks fine and will cover the cases when there was an error and we did not release the refcount.
>
> But, even in the normal cases I am not finding where we are releasing the refcount for the panel_node.
>
> I dont see a of_node_put() on mdp4_lcdc_encoder->panel_node.
>
Thanks for your review.
I don't see it either. It's a bit messy because the reference assigned to mdp4_lcdc_encoder->panel_node and mdp4_lvds_connector->panel_node both.
> Am i missing something?
>
>> diff --git a/drivers/gpu/drm/msm/disp/mdp4/mdp4_kms.c b/drivers/gpu/drm/msm/disp/mdp4/mdp4_kms.c
>> index fb48c8c19ec3..17cb1fc78379 100644
>> --- a/drivers/gpu/drm/msm/disp/mdp4/mdp4_kms.c
>> +++ b/drivers/gpu/drm/msm/disp/mdp4/mdp4_kms.c
>> @@ -216,6 +216,7 @@ static int mdp4_modeset_init_intf(struct mdp4_kms *mdp4_kms,
>> encoder = mdp4_lcdc_encoder_init(dev, panel_node);
>> if (IS_ERR(encoder)) {
>> DRM_DEV_ERROR(dev->dev, "failed to construct LCDC encoder\n");
>> + of_node_put(panel_node);
>> return PTR_ERR(encoder);
>> }
>> @@ -225,6 +226,7 @@ static int mdp4_modeset_init_intf(struct mdp4_kms *mdp4_kms,
>> connector = mdp4_lvds_connector_init(dev, panel_node, encoder);
>> if (IS_ERR(connector)) {
>> DRM_DEV_ERROR(dev->dev, "failed to initialize LVDS connector\n");
>> + of_node_put(panel_node);
>> return PTR_ERR(connector);
>> }
>>
On 6/14/2022 3:09 AM, Dmitry Baryshkov wrote:
> On 14/06/2022 13:07, Miaoqian Lin wrote:
>> Hi, Abhinav
>>
>> On 2022/6/11 7:20, Abhinav Kumar wrote:
>>>
>>>
>>> On 6/7/2022 4:08 AM, Miaoqian Lin wrote:
>>>> of_graph_get_remote_node() returns remote device node pointer with
>>>> refcount incremented, we should use of_node_put() on it
>>>> when not need anymore.
>>>> Add missing of_node_put() to avoid refcount leak.
>>>>
>>>> Fixes: 86418f90a4c1 ("drm: convert drivers to use
>>>> of_graph_get_remote_node")
>>>> Signed-off-by: Miaoqian Lin <[email protected]>
>>>> ---
>>>> drivers/gpu/drm/msm/disp/mdp4/mdp4_kms.c | 2 ++
>>>> 1 file changed, 2 insertions(+)
>>>>
>>>
>>> This patch itself looks fine and will cover the cases when there was
>>> an error and we did not release the refcount.
>>>
>>> But, even in the normal cases I am not finding where we are releasing
>>> the refcount for the panel_node.
>>>
>>> I dont see a of_node_put() on mdp4_lcdc_encoder->panel_node.
>>>
>> Thanks for your review.
>>
>> I don't see it either. It's a bit messy because the reference assigned
>> to mdp4_lcdc_encoder->panel_node and mdp4_lvds_connector->panel_node
>> both.
>
> I have a plan to rework mdp4 lcdc support once I get my ifc6410 lvds
> cable. Thus I think we can land this patch now and fix the mdp4
> lcdc/lvds code leaking the reference in the due time.
>
Alright, with that assurance,
Reviewed-by: Abhinav Kumar <[email protected]>
Will pick it up for -fixes.
>>
>>> Am i missing something?
>>>
>>>> diff --git a/drivers/gpu/drm/msm/disp/mdp4/mdp4_kms.c
>>>> b/drivers/gpu/drm/msm/disp/mdp4/mdp4_kms.c
>>>> index fb48c8c19ec3..17cb1fc78379 100644
>>>> --- a/drivers/gpu/drm/msm/disp/mdp4/mdp4_kms.c
>>>> +++ b/drivers/gpu/drm/msm/disp/mdp4/mdp4_kms.c
>>>> @@ -216,6 +216,7 @@ static int mdp4_modeset_init_intf(struct
>>>> mdp4_kms *mdp4_kms,
>>>> encoder = mdp4_lcdc_encoder_init(dev, panel_node);
>>>> if (IS_ERR(encoder)) {
>>>> DRM_DEV_ERROR(dev->dev, "failed to construct LCDC
>>>> encoder\n");
>>>> + of_node_put(panel_node);
>>>> return PTR_ERR(encoder);
>>>> }
>>>> @@ -225,6 +226,7 @@ static int mdp4_modeset_init_intf(struct
>>>> mdp4_kms *mdp4_kms,
>>>> connector = mdp4_lvds_connector_init(dev, panel_node,
>>>> encoder);
>>>> if (IS_ERR(connector)) {
>>>> DRM_DEV_ERROR(dev->dev, "failed to initialize LVDS
>>>> connector\n");
>>>> + of_node_put(panel_node);
>>>> return PTR_ERR(connector);
>>>> }
>
>