[PATCH V1] md:Fix name of raid thread when raid takeovered.

[majianpeng <majianpeng@gmail.com>]

When raid takeovered, it used old personality to set task->comm[].
So we add judgement and set corrected task->comm[].

Signed-off-by: majianpeng <majianpeng@gmail.com>
---
 drivers/md/md.c |   14 ++++++++++++++
 1 files changed, 14 insertions(+), 0 deletions(-)

diff --git a/drivers/md/md.c b/drivers/md/md.c
index 1c2f904..6b3ce6e 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -6738,11 +6738,25 @@ struct md_thread *md_register_thread(void (*run) (struct mddev *), struct mddev
 				 const char *name)
 {
 	struct md_thread *thread;
+	struct md_personality *pers = NULL;
 
 	thread = kzalloc(sizeof(struct md_thread), GFP_KERNEL);
 	if (!thread)
 		return NULL;
 
+	/*
+	 *When raid takeovered,the mddev->pers was old,so the
+	 *thread_name is wrong.
+	 */
+	if (name == NULL && mddev->level != mddev->new_level) {
+		spin_lock(&pers_lock);
+		list_for_each_entry(pers, &pers_list, list)
+			if (pers->level == mddev->new_level) {
+				name = pers->name;
+				break;
+			}
+		spin_unlock(&pers_lock);
+	}
 	init_waitqueue_head(&thread->wqueue);
 
 	thread->run = run;
-- 
1.7.5.4