[PATCH 4.17 084/324] nvme-pci: move nvme_kill_queues to nvme_remove_dead_ctrl

[Greg Kroah-Hartman]

4.17-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Jianchao Wang <jianchao.w.wang@xxxxxxxxxx>

[ Upstream commit 9f9cafc14016f23f982d3ce18f9057923bd3037a ]

There is race between nvme_remove and nvme_reset_work that can
lead to io hang.

nvme_remove                    nvme_reset_work
                               -> nvme_remove_dead_ctrl
                                 -> nvme_dev_disable
                                   -> quiesce request_queue
                                 -> queue remove_work
-> cancel_work_sync reset_work
-> nvme_remove_namespaces
  -> splice ctrl->namespaces
                               nvme_remove_dead_ctrl_work
                               -> nvme_kill_queues
  -> nvme_ns_remove               do nothing
    -> blk_cleanup_queue
      -> blk_freeze_queue

Finally, the request_queue is quiesced state when wait freeze,
we will get io hang here. To fix it, move the nvme_kill_queues
from nvme_remove_dead_ctrl_work to nvme_remove_dead_ctrl.

Suggested-by: Keith Busch <keith.busch@xxxxxxxxxxxxxxx>
Signed-off-by: Jianchao Wang <jianchao.w.wang@xxxxxxxxxx>
Reviewed-by: Keith Busch <keith.busch@xxxxxxxxx>
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/nvme/host/pci.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/nvme/host/pci.c
+++ b/drivers/nvme/host/pci.c
@@ -2291,6 +2291,7 @@ static void nvme_remove_dead_ctrl(struct
 
 	nvme_get_ctrl(&dev->ctrl);
 	nvme_dev_disable(dev, false);
+	nvme_kill_queues(&dev->ctrl);
 	if (!queue_work(nvme_wq, &dev->remove_work))
 		nvme_put_ctrl(&dev->ctrl);
 }
@@ -2407,7 +2408,6 @@ static void nvme_remove_dead_ctrl_work(s
 	struct nvme_dev *dev = container_of(work, struct nvme_dev, remove_work);
 	struct pci_dev *pdev = to_pci_dev(dev->dev);
 
-	nvme_kill_queues(&dev->ctrl);
 	if (pci_get_drvdata(pdev))
 		device_release_driver(&pdev->dev);
 	nvme_put_ctrl(&dev->ctrl);