Re: [PATCH 2/3] nvme-multipath: cannot disconnect controller on stuck partition scan

[Keith Busch <kbusch@kernel.org>]

On Tue, Oct 08, 2024 at 09:17:47AM +0200, Hannes Reinecke wrote:
> Hmm. Sadly, not really. Still stuck in partition scanning.
>
> Guess we'll need to check if we have paths available before triggering
> partition scan; let me check ...

I think you must have two paths, and the 2nd path cleared the suppress
bit before the 1st one finished its called to device_add_disk(). How
about this one?

---
diff --git a/drivers/nvme/host/multipath.c b/drivers/nvme/host/multipath.c
index 48e7a8906d012..755495f387168 100644
--- a/drivers/nvme/host/multipath.c
+++ b/drivers/nvme/host/multipath.c
@@ -586,6 +586,13 @@ static void nvme_requeue_work(struct work_struct *work)
 		container_of(work, struct nvme_ns_head, requeue_work);
 	struct bio *bio, *next;
 
+	if (disk_live(head->disk) &&
+	    test_and_clear_bit(GD_SUPPRESS_PART_SCAN, &head->disk->state)) {
+		mutex_lock(&head->disk->open_mutex);
+		bdev_disk_changed(head->disk, false);
+		mutex_unlock(&head->disk->open_mutex);
+	}
+
 	spin_lock_irq(&head->requeue_lock);
 	next = bio_list_get(&head->requeue_list);
 	spin_unlock_irq(&head->requeue_lock);
@@ -629,6 +636,7 @@ int nvme_mpath_alloc_disk(struct nvme_ctrl *ctrl, struct nvme_ns_head *head)
 		return PTR_ERR(head->disk);
 	head->disk->fops = &nvme_ns_head_ops;
 	head->disk->private_data = head;
+	set_bit(GD_SUPPRESS_PART_SCAN, &head->disk->state);
 	sprintf(head->disk->disk_name, "nvme%dn%d",
 			ctrl->subsys->instance, head->instance);
 	return 0;
--