From: Paolo Valente <paolo.valente@xxxxxxxxxx> commit c8997736650060594845e42c5d01d3118aec8d25 upstream. A bfq_put_queue() may be invoked in __bfq_bic_change_cgroup(). The goal of this put is to release a process reference to a bfq_queue. But process-reference releases may trigger also some extra operation, and, to this goal, are handled through bfq_release_process_ref(). So, turn the invocation of bfq_put_queue() into an invocation of bfq_release_process_ref(). Tested-by: cki-project@xxxxxxxxxx Signed-off-by: Paolo Valente <paolo.valente@xxxxxxxxxx> Signed-off-by: Jens Axboe <axboe@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- block/bfq-cgroup.c | 5 +---- block/bfq-iosched.c | 2 -- block/bfq-iosched.h | 1 + 3 files changed, 2 insertions(+), 6 deletions(-) --- a/block/bfq-cgroup.c +++ b/block/bfq-cgroup.c @@ -714,10 +714,7 @@ static struct bfq_group *__bfq_bic_chang if (entity->sched_data != &bfqg->sched_data) { bic_set_bfqq(bic, NULL, 0); - bfq_log_bfqq(bfqd, async_bfqq, - "bic_change_group: %p %d", - async_bfqq, async_bfqq->ref); - bfq_put_queue(async_bfqq); + bfq_release_process_ref(bfqd, async_bfqq); } } --- a/block/bfq-iosched.c +++ b/block/bfq-iosched.c @@ -2716,8 +2716,6 @@ static void bfq_bfqq_save_state(struct b } } - -static void bfq_release_process_ref(struct bfq_data *bfqd, struct bfq_queue *bfqq) { /* --- a/block/bfq-iosched.h +++ b/block/bfq-iosched.h @@ -955,6 +955,7 @@ void bfq_bfqq_expire(struct bfq_data *bf bool compensate, enum bfqq_expiration reason); void bfq_put_queue(struct bfq_queue *bfqq); void bfq_end_wr_async_queues(struct bfq_data *bfqd, struct bfq_group *bfqg); +void bfq_release_process_ref(struct bfq_data *bfqd, struct bfq_queue *bfqq); void bfq_schedule_dispatch(struct bfq_data *bfqd); void bfq_put_async_queues(struct bfq_data *bfqd, struct bfq_group *bfqg);