[PATCH v3 2/9] suppress "Device nodeX does not have a release() function" warning

[wency@cn.fujitsu.com]

From: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>

When calling unregister_node(), the function shows following message at
device_release().

"Device 'node2' does not have a release() function, it is broken and must
be fixed."

The reason is node's device struct does not have a release() function.

So the patch registers node_device_release() to the device's release()
function for suppressing the warning message. Additionally, the patch adds
memset() to initialize a node struct into register_node(). Because the node
struct is part of node_devices[] array and it cannot be freed by
node_device_release(). So if system reuses the node struct, it has a garbage.

CC: David Rientjes <rientjes@google.com>
CC: Jiang Liu <liuj97@gmail.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
---
 drivers/base/node.c |    6 ++++++
 1 files changed, 6 insertions(+), 0 deletions(-)

diff --git a/drivers/base/node.c b/drivers/base/node.c
index af1a177..2baa73a 100644
--- a/drivers/base/node.c
+++ b/drivers/base/node.c
@@ -252,6 +252,9 @@ static inline void hugetlb_register_node(struct node *node) {}
 static inline void hugetlb_unregister_node(struct node *node) {}
 #endif
 
+static void node_device_release(struct device *dev)
+{
+}
 
 /*
  * register_node - Setup a sysfs device for a node.
@@ -263,8 +266,11 @@ int register_node(struct node *node, int num, struct node *parent)
 {
 	int error;
 
+	memset(node, 0, sizeof(*node));
+
 	node->dev.id = num;
 	node->dev.bus = &node_subsys;
+	node->dev.release = node_device_release;
 	error = device_register(&node->dev);
 
 	if (!error){
-- 
1.7.1

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>