[PATCH] driver/base/node: remove unnecessary kfree of node struct from unregister_one_node

[Yasuaki Ishimatsu <isimatu.yasuaki@xxxxxxxxxxxxxx>]

Commit 92d585ef067d ("numa: fix NULL pointer access and memory
leak in unregister_one_node()") added kfree() of node struct in
unregister_one_node(). But node struct is freed by node_device_release()
which is called in  unregister_node(). So by adding the kfree(),
node struct is freed two times.

While hot removing memory, the commit leads the following BUG_ON():

  kernel BUG at mm/slub.c:3346!
  invalid opcode: 0000 [#1] SMP
  [...]
  Call Trace:
   [...] unregister_one_node
   [...] try_offline_node
   [...] remove_memory
   [...] acpi_memory_device_remove
   [...] acpi_bus_trim
   [...] acpi_bus_trim
   [...] acpi_device_hotplug
   [...] acpi_hotplug_work_fn
   [...] process_one_work
   [...] worker_thread
   [...] ? rescuer_thread
   [...] kthread
   [...] ? kthread_create_on_node
   [...] ret_from_fork
   [...] ? kthread_create_on_node

This patch removes unnecessary kfree() from unregister_one_node().

Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@xxxxxxxxxxxxxx>
Cc: Xishi Qiu <qiuxishi@xxxxxxxxxx>
Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx # v3.16+
Fixes: 92d585ef067d "numa: fix NULL pointer access and memory leak in unregister_one_node()"
---
 drivers/base/node.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/drivers/base/node.c b/drivers/base/node.c
index c6d3ae0..d51c49c 100644
--- a/drivers/base/node.c
+++ b/drivers/base/node.c
@@ -603,7 +603,6 @@ void unregister_one_node(int nid)
 		return;

 	unregister_node(node_devices[nid]);
-	kfree(node_devices[nid]);
 	node_devices[nid] = NULL;
 }

-- 
1.8.3.1


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