[PATCH V6 11/11] nvme: pci: support nested EH

[keith.busch@linux.intel.com (Keith Busch)]

Hi Ming,

I'm developing the answers in code the issues you raised. It will just
take a moment to complete flushing those out. In the meantime just want
to point out why I think block/011 isn't a real test.

On Thu, May 17, 2018@07:10:59AM +0800, Ming Lei wrote:
> All simulation in block/011 may happen in reality.

If this test actually simulates reality, then the following one line
patch (plus explanation for why) would be a real "fix" as this is very
successful in passing block/011. :)

---
diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c
index 1faa32cd07da..dcc5746304c4 100644
--- a/drivers/nvme/host/pci.c
+++ b/drivers/nvme/host/pci.c
@@ -2118,6 +2118,12 @@ static int nvme_pci_enable(struct nvme_dev *dev)
 
 	if (pci_enable_device_mem(pdev))
 		return result;
+	/*
+	 * blktests block/011 disables the device without the driver knowing.
+	 * We'll just enable the device twice to get the enable_cnt > 1
+	 * so that the test's disabling does absolutely nothing.
+	 */
+	pci_enable_device_mem(pdev);
 
 	pci_set_master(pdev);
--