From: Keith Busch <keith.busch@intel.com>
Date: Wed, 24 Jan 2018 14:55:12 -0700
Subject: nvme-pci: Suspend queues after deleting them
Patch-mainline: v4.16-rc1
Git-commit: ee9aebb27cbdac677525e0e56e8844cf4bf46461
References: FATE#323952, FATE#322506

The driver had been abusing the cq_vector state to know if new submissions
were safe, but that was before we could quiesce blk-mq. If the controller
happens to get an interrupt through while we're suspending those queues,
'no irq handler' warnings may occur.

This patch will disable the interrupts only after the queues are deleted.

Reported-by: Jianchao Wang <jianchao.w.wang@oracle.com>
Tested-by: Jianchao Wang <jianchao.w.wang@oracle.com>
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Johannes Thumshirn <jthumshirn@suse.de>
---
 drivers/nvme/host/pci.c |   27 ++++++++-------------------
 1 file changed, 8 insertions(+), 19 deletions(-)

--- a/drivers/nvme/host/pci.c
+++ b/drivers/nvme/host/pci.c
@@ -1322,9 +1322,6 @@ static void nvme_disable_admin_queue(str
 {
 	struct nvme_queue *nvmeq = &dev->queues[0];
 
-	if (nvme_suspend_queue(nvmeq))
-		return;
-
 	if (shutdown)
 		nvme_shutdown_ctrl(&dev->ctrl);
 	else
@@ -2009,9 +2006,9 @@ static int nvme_delete_queue(struct nvme
 	return 0;
 }
 
-static void nvme_disable_io_queues(struct nvme_dev *dev, int queues)
+static void nvme_disable_io_queues(struct nvme_dev *dev)
 {
-	int pass;
+	int pass, queues = dev->online_queues - 1;
 	unsigned long timeout;
 	u8 opcode = nvme_admin_delete_sq;
 
@@ -2162,7 +2159,7 @@ static void nvme_pci_disable(struct nvme
 
 static void nvme_dev_disable(struct nvme_dev *dev, bool shutdown)
 {
-	int i, queues;
+	int i;
 	bool dead = true;
 	struct pci_dev *pdev = to_pci_dev(dev->dev);
 
@@ -2197,21 +2194,13 @@ static void nvme_dev_disable(struct nvme
 	}
 	nvme_stop_queues(&dev->ctrl);
 
-	queues = dev->online_queues - 1;
-	for (i = dev->ctrl.queue_count - 1; i > 0; i--)
-		nvme_suspend_queue(&dev->queues[i]);
-
-	if (dead) {
-		/* A device might become IO incapable very soon during
-		 * probe, before the admin queue is configured. Thus,
-		 * queue_count can be 0 here.
-		 */
-		if (dev->ctrl.queue_count)
-			nvme_suspend_queue(&dev->queues[0]);
-	} else {
-		nvme_disable_io_queues(dev, queues);
+	if (!dead) {
+		nvme_disable_io_queues(dev);
 		nvme_disable_admin_queue(dev, shutdown);
 	}
+	for (i = dev->ctrl.queue_count - 1; i >= 0; i--)
+		nvme_suspend_queue(&dev->queues[i]);
+
 	nvme_pci_disable(dev);
 
 	blk_mq_tagset_busy_iter(&dev->tagset, nvme_cancel_request, &dev->ctrl);