nvme-pci: Skip queue deletion if there are no queues

User reported controller always retains CSTS.RDY to 1, which fails
controller disabling when resetting the controller. This is also before
the admin queue is allocated, and trying to disable an unallocated queue
results in a NULL dereference.

Reported-by: Alex Gagniuc <Alex_Gagniuc@Dellteam.com>
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c
index 295fbec..22403aa 100644 (file)
--- a/drivers/nvme/host/pci.c
+++ b/drivers/nvme/host/pci.c
@@ -2201,7 +2201,7 @@ static void nvme_dev_disable(struct nvme_dev *dev, bool shutdown)
 
        nvme_stop_queues(&dev->ctrl);
 
-       if (!dead) {
+       if (!dead && dev->ctrl.queue_count > 0) {
                /*
                 * If the controller is still alive tell it to stop using the
                 * host memory buffer.  In theory the shutdown / reset should