On Sat, 2017-04-29 at 07:38 +0200, Markus Trippelsdorf wrote:
> 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.
>
> diff --git a/block/elevator.c b/block/elevator.c
> index bf11e70f008b..4f13fcd3c626 100644
> --- a/block/elevator.c
> +++ b/block/elevator.c
> @@ -1112,6 +1112,7 @@ 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))
> @@ -1121,7 +1122,9 @@ ssize_t elv_iosched_store(struct request_queue *q,
> const char *name,
> if (!ret)
> return count;
>
> - printk(KERN_ERR "elevator: switch to %s failed\n", name);
> + strlcpy(elevator_name, name, sizeof(elevator_name));
> + strstrip(elevator_name);
> + printk(KERN_ERR "elevator: switch to %s failed\n", elevator_name);
> return ret;
> }
Hello Markus,
Your patch duplicates the code to remove trailing whitespace which is not
very elegant. Please move the code that removes trailing whitespace from
__elevator_change() into elv_iosched_store() instead of duplicating it.
Thanks,
Bart.