Commit 8730c1dd authored by Hannes Reinecke's avatar Hannes Reinecke Committed by Christoph Hellwig
Browse files

nvme-fc: use separate work queue to avoid warning 



When tearing down a controller the following warning is issued:

WARNING: CPU: 0 PID: 30681 at ../kernel/workqueue.c:2418 check_flush_dependency

This happens as the err_work workqueue item is scheduled on the
system workqueue (which has WQ_MEM_RECLAIM not set), but is flushed
from a workqueue which has WQ_MEM_RECLAIM set.

Fix this by providing an FC-NVMe specific workqueue.

Fixes: 4cff280a ("nvme-fc: resolve io failures during connect")
Signed-off-by: default avatarHannes Reinecke <hare@suse.com>
Reviewed-by: default avatarJames Smart <james.smart@broadcom.com>
Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
parent 87fd1253

drivers/nvme/host/fc.c

+11 −3
Original line number Diff line number Diff line
@@ -202,7 +202,7 @@ static LIST_HEAD(nvme_fc_lport_list); 
static DEFINE_IDA(nvme_fc_local_port_cnt);

static DEFINE_IDA(nvme_fc_ctrl_cnt);





static struct workqueue_struct *nvme_fc_wq;



/*

 * These items are short-term. They will eventually be moved into
@@ -2054,7 +2054,7 @@ nvme_fc_error_recovery(struct nvme_fc_ctrl *ctrl, char *errmsg) 
	 */

	if (ctrl->ctrl.state == NVME_CTRL_CONNECTING) {

		active = atomic_xchg(&ctrl->err_work_active, 1);

		if (!active && !schedule_work(&ctrl->err_work)) {

		if (!active && !queue_work(nvme_fc_wq, &ctrl->err_work)) {

			atomic_set(&ctrl->err_work_active, 0);

			WARN_ON(1);

		}
@@ -3399,6 +3399,10 @@ static int __init nvme_fc_init_module(void) 
{

	int ret;



	nvme_fc_wq = alloc_workqueue("nvme_fc_wq", WQ_MEM_RECLAIM, 0);

	if (!nvme_fc_wq)

		return -ENOMEM;



	/*

	 * NOTE:

	 * It is expected that in the future the kernel will combine
@@ -3416,7 +3420,7 @@ static int __init nvme_fc_init_module(void) 
	ret = class_register(&fc_class);

	if (ret) {

		pr_err("couldn't register class fc\n");

		return ret;

		goto out_destroy_wq;

	}



	/*
@@ -3440,6 +3444,9 @@ out_destroy_device: 
	device_destroy(&fc_class, MKDEV(0, 0));

out_destroy_class:

	class_unregister(&fc_class);

out_destroy_wq:

	destroy_workqueue(nvme_fc_wq);



	return ret;

}
@@ -3456,6 +3463,7 @@ static void __exit nvme_fc_exit_module(void) 


	device_destroy(&fc_class, MKDEV(0, 0));

	class_unregister(&fc_class);

	destroy_workqueue(nvme_fc_wq);

}



module_init(nvme_fc_init_module);

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