[PATCH 0/3] delete unneeded of_node_put

[PATCH 0/3] delete unneeded of_node_put

[Julia Lawall]

Device node iterators perform an of_node_put on each iteration, so putting
an of_node_put before going around to the next iteration results in a
double put.

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

// <smpl>
@r exists@
expression e1,e2;
local idexpression n;
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;
position p1,p2;
statement S;
@@

(
(
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 at p1(...) {
   ... when != of_node_get(n)
       when any
   of_node_put at p2(n);
   ... when any
}
)

@s exists@
local idexpression r.n;
statement S;
position r.p1,r.p2;
iterator i;
@@

 of_node_put at p2(n);
 ... when any
 i at p1(..., n, ...)
 S

@depends on s@
local idexpression n;
position r.p2;
@@

- of_node_put at p2(n);
// </smpl>

---

 arch/arm/mach-exynos/pm_domains.c                 |    8 +++-----
 drivers/soc/qcom/smd.c                            |    4 +---
 drivers/video/fbdev/omap2/dss/omapdss-boot-init.c |    4 +---
 3 files changed, 5 insertions(+), 11 deletions(-)

[PATCH 3/3] ARM: EXYNOS: delete unneeded of_node_put

[Julia Lawall]

Device node iterators perform an of_node_put on each iteration, so putting
an of_node_put before going around to the next iteration results in a
double put.

Problem found using Coccinelle.

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

---
 arch/arm/mach-exynos/pm_domains.c |    8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/arch/arm/mach-exynos/pm_domains.c b/arch/arm/mach-exynos/pm_domains.c
index 4a87e86..7c21760 100644
--- a/arch/arm/mach-exynos/pm_domains.c
+++ b/arch/arm/mach-exynos/pm_domains.c
@@ -200,15 +200,15 @@ no_clk:
 		args.args_count = 0;
 		child_domain = of_genpd_get_from_provider(&args);
 		if (IS_ERR(child_domain))
-			goto next_pd;
+			continue;
 
 		if (of_parse_phandle_with_args(np, "power-domains",
 					 "#power-domain-cells", 0, &args) != 0)
-			goto next_pd;
+			continue;
 
 		parent_domain = of_genpd_get_from_provider(&args);
 		if (IS_ERR(parent_domain))
-			goto next_pd;
+			continue;
 
 		if (pm_genpd_add_subdomain(parent_domain, child_domain))
 			pr_warn("%s failed to add subdomain: %s\n",
@@ -216,8 +216,6 @@ no_clk:
 		else
 			pr_info("%s has as child subdomain: %s.\n",
 				parent_domain->name, child_domain->name);
-next_pd:
-		of_node_put(np);
 	}
 
 	return 0;

[PATCH 3/3] ARM: EXYNOS: delete unneeded of_node_put

[Javier Martinez Canillas]

Hello Julia,

On 10/12/2015 10:43 PM, Julia Lawall wrote:
> Device node iterators perform an of_node_put on each iteration, so putting
> an of_node_put before going around to the next iteration results in a
> double put.
> 
> Problem found using Coccinelle.
> 
> Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
>

Krzysztof sent the same patch yesterday and was already applied:
https://lkml.org/lkml/2015/10/12/688

Best regards,
-- 
Javier Martinez Canillas
Open Source Group
Samsung Research America