mtd: brcmnand: improve memory management
Author: Julia Lawall <julia.lawall@lip6.fr>
This patch addresses two related memory management issues in the probe
function:
1. for_each_available_child_of_node performs an of_node_get on each
iteration, so a break 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):
//
@@
expression root,e;
local idexpression child;
@@
for_each_available_child_of_node(root, child) {
... when != of_node_put(child)
when != e = child
(
return child;
|
+ of_node_put(child);
? return ...;
)
...
}
//
2. The devm_kzalloc'd data is not used if brcmnand_init_cs fails. Free it
immediately, using devm_kfree in this case, instead of waiting for the
remove function.
Signed-off-by: Julia Lawall
Signed-off-by: Brian Norris
---
drivers/mtd/nand/brcmnand/brcmnand.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)
diff --git a/drivers/mtd/nand/brcmnand/brcmnand.c b/drivers/mtd/nand/brcmnand/brcmnand.c
index 8feee1e..ad756f6 100644
--- a/drivers/mtd/nand/brcmnand/brcmnand.c
+++ b/drivers/mtd/nand/brcmnand/brcmnand.c
@@ -2233,15 +2233,19 @@ int brcmnand_probe(struct platform_device *pdev, struct brcmnand_soc *soc)
struct brcmnand_host *host;
host = devm_kzalloc(dev, sizeof(*host), GFP_KERNEL);
- if (!host)
+ if (!host) {
+ of_node_put(child);
return -ENOMEM;
+ }
host->pdev = pdev;
host->ctrl = ctrl;
host->of_node = child;
ret = brcmnand_init_cs(host);
- if (ret)
+ if (ret) {
+ devm_kfree(dev, host);
continue; /* Try all chip-selects */
+ }
list_add_tail(&host->node, &ctrl->host_list);
} |
---
drivers/mtd/nand/brcmnand/brcmnand.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)
diff --git a/drivers/mtd/nand/brcmnand/brcmnand.c b/drivers/mtd/nand/brcmnand/brcmnand.c
index 8feee1e..ad756f6 100644
--- a/drivers/mtd/nand/brcmnand/brcmnand.c
+++ b/drivers/mtd/nand/brcmnand/brcmnand.c
@@ -2233,15 +2233,19 @@ int brcmnand_probe(struct platform_device *pdev, struct brcmnand_soc *soc)
struct brcmnand_host *host;
host = devm_kzalloc(dev, sizeof(*host), GFP_KERNEL);
- if (!host)
+ if (!host) {
+ of_node_put(child);
return -ENOMEM;
+ }
host->pdev = pdev;
host->ctrl = ctrl;
host->of_node = child;
ret = brcmnand_init_cs(host);
- if (ret)
+ if (ret) {
+ devm_kfree(dev, host);
continue; /* Try all chip-selects */
+ }
list_add_tail(&host->node, &ctrl->host_list);
}