Memory will be allocated to store substring_t in match_strdup(), which
means the caller of match_strdup() may need to be scheduled out to wait
for reclaiming memory. smatch complains that this can cuase sleeping in
an atoic context.
Using local array to store substring_t to remove the restriction.
Link: https://lkml.kernel.org/r/20230120032352.242767-1-lilingfeng3@huawei.com
Link: https://lore.kernel.org/all/20221104023938.2346986-5-yukuai1@huaweicloud.com/
Link: https://lkml.kernel.org/r/20230120032352.242767-1-lilingfeng3@huawei.com
Fixes: 2c06479884 ("blk-iocost: don't release 'ioc->lock' while updating params")
Signed-off-by: Li Lingfeng <lilingfeng3@huawei.com>
Reported-by: Yu Kuai <yukuai1@huaweicloud.com>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: BingJing Chang <bingjingc@synology.com>
Cc: Eric Biggers <ebiggers@google.com>
Cc: Hou Tao <houtao1@huawei.com>
Cc: James Smart <james.smart@broadcom.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: yangerkun <yangerkun@huawei.com>
Cc: Zhang Yi <yi.zhang@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
