nvme/pci: Fix hot removal during error handling

A removal waits for the reset_work to complete. If a surprise removal occurs around the same time as an error triggered controller reset, and reset work happened to dispatch a command to the removed controller, the command won't be recovered since the timeout work doesn't do anything during error recovery. We wouldn't want to wait for timeout handling anyway, so this patch fixes this by disabling the controller and killing admin queues prior to syncing with the reset_work.

---
v2->v3:
Just keep the existing flush_work instead of replacing it with cancel_work_sync.

 drivers/nvme/host/pci.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

index 450481c2fd17..72737009b82d 100644
@@ -2564,13 +2564,12 @@ static void nvme_remove(struct pci_dev *pdev)
 	struct nvme_dev *dev = pci_get_drvdata(pdev);
 
 	nvme_change_ctrl_state(&dev->ctrl, NVME_CTRL_DELETING);
-
-	cancel_work_sync(&dev->ctrl.reset_work);
 	pci_set_drvdata(pdev, NULL);
 
 	if (!pci_device_is_present(pdev)) {
 		nvme_change_ctrl_state(&dev->ctrl, NVME_CTRL_DEAD);
 		nvme_dev_disable(dev, true);
+		nvme_dev_remove_admin(dev);
 	}
 
 	flush_work(&dev->ctrl.reset_work);

2.14.4

Thanks,

applied to nvme-4.20.