On 12/3/18 3:02 AM, Ming Lei wrote: > Hi, > > Just found there is sbmitmap related lockdep warning, not take a close > look yet, maybe > it is caused by recent sbitmap change. > > [1] test > - modprobe null_blk queue_mode=2 nr_devices=4 shared_tags=1 > submit_queues=1 hw_queue_depth=1 > - then run fio on the 4 null_blk devices
This is a false positive - lockdep thinks that ->swap_lock needs to be IRQ safe since it's called with IRQs disabled from the blk_mq_mark_tag_wait() path. But we never grab the lock from IRQ context. I wonder how to teach lockdep about that... -- Jens Axboe
