On 03/29/2017 11:20 PM, Minchan Kim wrote: > In blk_mq_alloc_request_hctx, blk_mq_sched_get_request doesn't > get sw context so we don't need to put the context with > blk_mq_put_ctx. Unless, we will see preempt counter underflow. Good catch, that's definitely a bug. I have applied your patch for 4.11. -- Jens Axboe