NVMe: Fix filesystem deadlock on removal

Move gendisk deletion before controller shutdown so filesystem may sync
dirty pages. Before, this would deadlock trying to allocate requests
on frozen queues that are about to be deleted.

Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>

drivers/block/nvme-core.c

@@ -3124,8 +3124,8 @@ static void nvme_remove(struct pci_dev *pdev)
 	flush_work(&dev->reset_work);
 	flush_work(&dev->scan_work);
 	device_remove_file(dev->device, &dev_attr_reset_controller);
-	nvme_dev_shutdown(dev);
 	nvme_dev_remove(dev);
+	nvme_dev_shutdown(dev);
 	nvme_dev_remove_admin(dev);
 	device_destroy(nvme_class, MKDEV(nvme_char_major, dev->instance));
 	nvme_free_queues(dev, 0);