Commit 5ea7c133 authored by Jack Wang's avatar Jack Wang Committed by Jens Axboe
Browse files

block/rnbd-clt: Avoid flush_workqueue(system_long_wq) usage 

Flushing system-wide workqueues is dangerous and will be forbidden.

Replace system_long_wq with local rnbd_clt_wq.

Link: https://lkml.kernel.org/r/49925af7-78a8-a3dd-bce6-cfc02e1a9236@I-love.SAKURA.ne.jp



Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: default avatarJack Wang <jinpu.wang@ionos.com>
Reviewed-by: default avatarSantosh Kumar Pradhan <santosh.pradhan@ionos.com>
Link: https://lore.kernel.org/r/20220413123420.66470-1-jinpu.wang@ionos.com


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent d292dc80

drivers/block/rnbd/rnbd-clt.c

+12 −2
Original line number Diff line number Diff line
@@ -25,6 +25,7 @@ static int rnbd_client_major; 
static DEFINE_IDA(index_ida);

static DEFINE_MUTEX(sess_lock);

static LIST_HEAD(sess_list);

static struct workqueue_struct *rnbd_clt_wq;



/*

 * Maximum number of partitions an instance can have.
@@ -1759,12 +1760,12 @@ static void rnbd_destroy_sessions(void) 
			 * procedure takes minutes.

			 */

			INIT_WORK(&dev->unmap_on_rmmod_work, unmap_device_work);

			queue_work(system_long_wq, &dev->unmap_on_rmmod_work);

			queue_work(rnbd_clt_wq, &dev->unmap_on_rmmod_work);

		}

		rnbd_clt_put_sess(sess);

	}

	/* Wait for all scheduled unmap works */

	flush_workqueue(system_long_wq);

	flush_workqueue(rnbd_clt_wq);

	WARN_ON(!list_empty(&sess_list));

}
@@ -1789,6 +1790,14 @@ static int __init rnbd_client_init(void) 
		pr_err("Failed to load module, creating sysfs device files failed, err: %d\n",

		       err);

		unregister_blkdev(rnbd_client_major, "rnbd");

		return err;

	}

	rnbd_clt_wq = alloc_workqueue("rnbd_clt_wq", 0, 0);

	if (!rnbd_clt_wq) {

		pr_err("Failed to load module, alloc_workqueue failed.\n");

		rnbd_clt_destroy_sysfs_files();

		unregister_blkdev(rnbd_client_major, "rnbd");

		err = -ENOMEM;

	}



	return err;
@@ -1799,6 +1808,7 @@ static void __exit rnbd_client_exit(void) 
	rnbd_destroy_sessions();

	unregister_blkdev(rnbd_client_major, "rnbd");

	ida_destroy(&index_ida);

	destroy_workqueue(rnbd_clt_wq);

}



module_init(rnbd_client_init);