Hi Ming On 09/13/2018 08:15 PM, Ming Lei wrote: > EXPORT_SYMBOL(__scsi_execute); > @@ -3246,6 +3251,7 @@ static int scsi_internal_device_block(struct scsi_device *sdev) > else > scsi_wait_for_queuecommand(sdev); > } > + wait_event(sdev->admin_wq, !atomic_read(&sdev->nr_admin_pending)); > mutex_unlock(&sdev->state_mutex); > > return err; ... > diff --git a/drivers/scsi/scsi_sysfs.c b/drivers/scsi/scsi_sysfs.c > index 3aee9464a7bf..8bcb7ecc0c06 100644 > --- a/drivers/scsi/scsi_sysfs.c > +++ b/drivers/scsi/scsi_sysfs.c > @@ -1393,6 +1393,7 @@ void __scsi_remove_device(struct scsi_device *sdev) > > blk_cleanup_queue(sdev->request_queue); > cancel_work_sync(&sdev->requeue_work); > + wait_event(sdev->admin_wq, !atomic_read(&sdev->nr_admin_pending)) This nr_admin_pending could drain the ongoing scsi_request_fn/scsi_queue_rq, but I'm afraid it cannot stop new ones coming in, such as the ones that have passed the sdev state checking and have not crossed the atomic_inc(&sdev->nr_admin_pending). Thanks Jianchao