Commit 8c7b5b4e authored Dec 11, 2012 by Yasuaki Ishimatsu Committed by Linus Torvalds Dec 11, 2012

memory-hotplug: suppress "Device nodeX does not have a release() function" warning



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.

Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Jiang Liu <liuj97@gmail.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent 8732794b

drivers/base/node.c

+19 −1

Original line number	Diff line number	Diff line
		@@ -252,6 +252,24 @@ 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)
		{
		struct node *node = to_node(dev);

		#if defined(CONFIG_MEMORY_HOTPLUG_SPARSE) && defined(CONFIG_HUGETLBFS)
		/*
		* We schedule the work only when a memory section is
		* onlined/offlined on this node. When we come here,
		* all the memory on this node has been offlined,
		* so we won't enqueue new work to this work.
		*
		* The work is using node->node_work, so we should
		* flush work before freeing the memory.
		*/
		flush_work(&node->node_work);
		#endif
		kfree(node);
		}

		/*
		* register_node - Setup a sysfs device for a node.
		@@ -265,6 +283,7 @@ int register_node(struct node node, int num, struct node parent)

		node->dev.id = num;
		node->dev.bus = &node_subsys;
		node->dev.release = node_device_release;
		error = device_register(&node->dev);

		if (!error){
		@@ -586,7 +605,6 @@ int register_one_node(int nid)
		void unregister_one_node(int nid)
		{
		unregister_node(node_devices[nid]);
		kfree(node_devices[nid]);
		node_devices[nid] = NULL;
		}

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