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

Greg Kroah-Hartman
2018-08-23T08:43:32Z

From: Jianchao Wang <jianchao.w.wang@oracle.com>

[ 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@linux.intel.com>
Signed-off-by: Jianchao Wang <jianchao.w.wang@oracle.com>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
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);