Trying to switch to a non-existing elevator currently results in garbled
dmesg output, e.g.:

 # echo "foo" > /sys/block/sda/queue/scheduler 

elevator: type foo not found
elevator: switch to foo
 failed

(note the unintended line break.)

Fix by stripping the trailing newline.

Signed-off-by: Markus Trippelsdorf <[email protected]>

diff --git a/block/elevator.c b/block/elevator.c
index bf11e70f008b..1af23eee4395 100644
--- a/block/elevator.c
+++ b/block/elevator.c
@@ -1054,7 +1054,6 @@ static int elevator_switch(struct request_queue *q, 
struct elevator_type *new_e)
  */
 static int __elevator_change(struct request_queue *q, const char *name)
 {
-       char elevator_name[ELV_NAME_MAX];
        struct elevator_type *e;
 
        /*
@@ -1063,15 +1062,14 @@ static int __elevator_change(struct request_queue *q, 
const char *name)
        if (q->mq_ops && !strncmp(name, "none", 4))
                return elevator_switch(q, NULL);
 
-       strlcpy(elevator_name, name, sizeof(elevator_name));
-       e = elevator_get(strstrip(elevator_name), true);
+       e = elevator_get(name, true);
        if (!e) {
-               printk(KERN_ERR "elevator: type %s not found\n", elevator_name);
+               printk(KERN_ERR "elevator: type %s not found\n", name);
                return -EINVAL;
        }
 
        if (q->elevator &&
-           !strcmp(elevator_name, q->elevator->type->elevator_name)) {
+           !strcmp(name, q->elevator->type->elevator_name)) {
                elevator_put(e);
                return 0;
        }
@@ -1112,16 +1110,19 @@ static inline bool elv_support_iosched(struct 
request_queue *q)
 ssize_t elv_iosched_store(struct request_queue *q, const char *name,
                          size_t count)
 {
+       char elevator_name[ELV_NAME_MAX];
        int ret;
 
        if (!(q->mq_ops || q->request_fn) || !elv_support_iosched(q))
                return count;
 
-       ret = __elevator_change(q, name);
+       strlcpy(elevator_name, name, sizeof(elevator_name));
+       strstrip(elevator_name);
+       ret = __elevator_change(q, elevator_name);
        if (!ret)
                return count;
 
-       printk(KERN_ERR "elevator: switch to %s failed\n", name);
+       printk(KERN_ERR "elevator: switch to %s failed\n", elevator_name);
        return ret;
 }
 
-- 
Markus

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