[PATCH 0/5] add missing of_node_put

[PATCH 0/5] add missing of_node_put

[Julia Lawall]

The various for_each device_node iterators performs an of_node_get on each
iteration, so a break out of the loop requires an of_node_put.

The complete semantic patch that fixes this problem is
(http://coccinelle.lip6.fr):

// <smpl>
@r@
local idexpression n;
expression e1,e2;
iterator name for_each_node_by_name, for_each_node_by_type,
for_each_compatible_node, for_each_matching_node,
for_each_matching_node_and_match, for_each_child_of_node,
for_each_available_child_of_node, for_each_node_with_property;
iterator i;
statement S;
expression list [n1] es;
@@

(
(
for_each_node_by_name(n,e1) S
|
for_each_node_by_type(n,e1) S
|
for_each_compatible_node(n,e1,e2) S
|
for_each_matching_node(n,e1) S
|
for_each_matching_node_and_match(n,e1,e2) S
|
for_each_child_of_node(e1,n) S
|
for_each_available_child_of_node(e1,n) S
|
for_each_node_with_property(n,e1) S
)
&
i(es,n,...) S
)

@@
local idexpression r.n;
iterator r.i;
expression e;
expression list [r.n1] es;
@@

 i(es,n,...) {
   ...
(
   of_node_put(n);
|
   e = n
|
   return n;
|
+  of_node_put(n);
?  return ...;
)
   ...
 }

@@
local idexpression r.n;
iterator r.i;
expression e;
expression list [r.n1] es;
@@

 i(es,n,...) {
   ...
(
   of_node_put(n);
|
   e = n
|
+  of_node_put(n);
?  break;
)
   ...
 }
... when != n

@@
local idexpression r.n;
iterator r.i;
expression e;
identifier l;
expression list [r.n1] es;
@@

 i(es,n,...) {
   ...
(
   of_node_put(n);
|
   e = n
|
+  of_node_put(n);
?  goto l;
)
   ...
 }
...
l: ... when != n// </smpl>

---

 drivers/pinctrl/mediatek/pinctrl-mtk-common.c |    1 +
 drivers/pinctrl/pinctrl-rockchip.c            |    5 ++++-
 drivers/pinctrl/pinctrl-tegra-xusb.c          |    4 +++-
 drivers/pinctrl/pinctrl-tegra.c               |    1 +
 drivers/pinctrl/sh-pfc/pinctrl.c              |    4 +++-
 drivers/pinctrl/sirf/pinctrl-sirf.c           |    8 ++++++--
 6 files changed, 18 insertions(+), 5 deletions(-)

[PATCH 3/5] pinctrl: sh-pfc: add missing of_node_put

[Julia Lawall]

for_each_child_of_node performs an of_node_get on each iteration, so a
goto out of the loop requires an of_node_put.

A simplified version of the semantic patch that fixes this problem is as
follows (http://coccinelle.lip6.fr):

// <smpl>
@@
local idexpression n;
expression e,e1;
identifier l;
@@

 for_each_child_of_node(e1,n) {
   ...
(
   of_node_put(n);
|
   e = n
|
   return n;
|
+  of_node_put(n);
?  goto l;
)
   ...
 }
l: ... when != n
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

---
 drivers/pinctrl/sh-pfc/pinctrl.c |    4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/pinctrl/sh-pfc/pinctrl.c b/drivers/pinctrl/sh-pfc/pinctrl.c
index 863c3e3..87b0a59 100644
--- a/drivers/pinctrl/sh-pfc/pinctrl.c
+++ b/drivers/pinctrl/sh-pfc/pinctrl.c
@@ -273,8 +273,10 @@ static int sh_pfc_dt_node_to_map(struct pinctrl_dev *pctldev,
 	for_each_child_of_node(np, child) {
 		ret = sh_pfc_dt_subnode_to_map(pctldev, child, map, num_maps,
 					       &index);
-		if (ret < 0)
+		if (ret < 0) {
+			of_node_put(child);
 			goto done;
+		}
 	}
 
 	/* If no mapping has been found in child nodes try the config node. */

Re: [PATCH 3/5] pinctrl: sh-pfc: add missing of_node_put

[Laurent Pinchart]

Hi Julia,

Thank you for the patch.

On Monday 21 December 2015 17:39:46 Julia Lawall wrote:
> for_each_child_of_node performs an of_node_get on each iteration, so a
> goto out of the loop requires an of_node_put.
> 
> A simplified version of the semantic patch that fixes this problem is as
> follows (http://coccinelle.lip6.fr):
> 
> // <smpl>
> @@
> local idexpression n;
> expression e,e1;
> identifier l;
> @@
> 
>  for_each_child_of_node(e1,n) {
>    ...
> (
>    of_node_put(n);
> 
>    e = n
> 
>    return n;
> 
> +  of_node_put(n);
> ?  goto l;
> )
>    ...
>  }
> l: ... when != n
> // </smpl>
> 
> Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

> ---
>  drivers/pinctrl/sh-pfc/pinctrl.c |    4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/pinctrl/sh-pfc/pinctrl.c
> b/drivers/pinctrl/sh-pfc/pinctrl.c index 863c3e3..87b0a59 100644
> --- a/drivers/pinctrl/sh-pfc/pinctrl.c
> +++ b/drivers/pinctrl/sh-pfc/pinctrl.c
> @@ -273,8 +273,10 @@ static int sh_pfc_dt_node_to_map(struct pinctrl_dev
> *pctldev, for_each_child_of_node(np, child) {
>  		ret = sh_pfc_dt_subnode_to_map(pctldev, child, map, num_maps,
>  					       &index);
> -		if (ret < 0)
> +		if (ret < 0) {
> +			of_node_put(child);
>  			goto done;
> +		}
>  	}
> 
>  	/* If no mapping has been found in child nodes try the config node. */

-- 
Regards,

Laurent Pinchart

Re: [PATCH 3/5] pinctrl: sh-pfc: add missing of_node_put

[Linus Walleij]

On Mon, Dec 21, 2015 at 5:39 PM, Julia Lawall <Julia.Lawall@lip6.fr> wrote:

> for_each_child_of_node performs an of_node_get on each iteration, so a
> goto out of the loop requires an of_node_put.
>
> A simplified version of the semantic patch that fixes this problem is as
> follows (http://coccinelle.lip6.fr):

Patch applied with Laurent's ACK.

Geert: since I don't think you're gonna send me more pull
requests before the merge window I went ahead and applied
this directly, OK?

Yours,
Linus Walleij

Re: [PATCH 3/5] pinctrl: sh-pfc: add missing of_node_put

[Geert Uytterhoeven]

Hi Linus,

On Tue, Dec 22, 2015 at 1:47 PM, Linus Walleij <linus.walleij@linaro.org> wrote:
> On Mon, Dec 21, 2015 at 5:39 PM, Julia Lawall <Julia.Lawall@lip6.fr> wrote:
>> for_each_child_of_node performs an of_node_get on each iteration, so a
>> goto out of the loop requires an of_node_put.
>>
>> A simplified version of the semantic patch that fixes this problem is as
>> follows (http://coccinelle.lip6.fr):
>
> Patch applied with Laurent's ACK.
>
> Geert: since I don't think you're gonna send me more pull
> requests before the merge window I went ahead and applied
> this directly, OK?

You're reading my mind ;-)

Thanks!

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds