Hello, In do_exit(), io_uring needs to wait pending requests. ublk is one uring_cmd driver, and its usage is a bit special by submitting command for waiting incoming block IO request in advance, so if there isn't any IO request coming, the command can't be completed. So far ublk driver has to bind its queue with one ublk daemon server, meantime starts one monitor work to check if this daemon is live periodically. This way requires ublk queue to be bound one single daemon pthread, and not flexible, meantime the monitor work is run in 3rd context, and the implementation is a bit tricky. The 1st 3 patches adds io_uring task exit notifier, and the other patches converts ublk into this exit notifier, and the implementation becomes more robust & readable, meantime it becomes easier to relax the ublk queue/daemon limit in future, such as not require to bind ublk queue with single daemon. Ming Lei (10): io_uring: allocate ctx id and build map between id and ctx io_uring: pass io_uring_ctx->id to uring_cmd io_uring: support io_uring notifier for uring_cmd ublk: don't get ublk device reference in ublk_abort_queue() ublk: make sure ublk uring cmd handling is done in submitter task context ublk: make sure that uring cmd aiming at same queue won't cross io_uring contexts ublk: rename mm_lock as lock ublk: quiesce request queue when aborting queue ublk: replace monitor work with uring_cmd exit notifier ublk: simplify aborting request drivers/block/ublk_drv.c | 216 +++++++++++++++++++-------------- include/linux/io_uring.h | 27 ++++- include/linux/io_uring_types.h | 3 + io_uring/io_uring.c | 57 +++++++++ io_uring/io_uring.h | 4 + io_uring/uring_cmd.c | 13 ++ 6 files changed, 230 insertions(+), 90 deletions(-) -- 2.40.1