1.Repeat steps: (1) send IO on the device /dev/sdx. (2) Simulate an IO lost (3) Use the command before to delete scsi device before IO timeout ehco 1 > /sys/class/sdx/device/delete 2.The stack of delete thead is before: [<ffffffff810999ef>] msleep+0x2f/0x40 [<ffffffff812f78b4>] __blk_drain_queue+0xa4/0x170 [<ffffffff812f7bfd>] blk_cleanup_queue+0x13d/0x150 [<ffffffff81473d2a>] __scsi_remove_device+0x4a/0xd0 [<ffffffff81473dd6>] scsi_remove_device+0x26/0x40 [<ffffffff81473e05>] sdev_store_delete_callback+0x15/0x20 [<ffffffff8127fdc4>] sysfs_schedule_callback_work+0x14/0x60 [<ffffffff810a881a>] process_one_work+0x17a/0x440 [<ffffffff810a94e6>] worker_thread+0x126/0x3c0 [<ffffffff810b098f>] kthread+0xcf/0xe0 [<ffffffff816b4f18>] ret_from_fork+0x58/0x90 3.The reason is before: (1) When the scsi device is deleted, invoke blk_cleanup_queue funtion to set the flag of request_queue dying, and wait all IO back. (2) when IO timout,the timeout workqueue invoke blk_timeout_work function to abort IO, but it will not abort the IO because it call blk_queue_enter funtion judge the request_queue is dying and return direct without doing anything.
