On Fri, Feb 07, 2020 at 08:24:59PM +0800, yukuai (C) wrote: > On 2020/2/7 18:26, yukuai (C) wrote: > > The reason of the problem is because the final release of request_queue > > may be called after loop_remove() returns. > > The description is not accurate. The reason of the problem is that > __blk_trace_setup() called before the final release of request_queue > returns.(step 4 before step 5) But blk_mq_debugfs_register() in your step 3 for adding loop still may fail, that is why I suggest to consider to move blk_mq_debugfs_register() into blk_unregister_queue(). Thanks, Ming
