nvme-pci: allocate tagset on reset if necessary

If a drive is unable to create IO queues on the initial probe, a
subsequent reset will need to allocate the tagset if IO queue creation
is successful. Without this, blk_mq_update_nr_hw_queues will crash on a
bad pointer due to the invalid tagset.

Fixes: eac3ef262941f62 ("nvme-pci: split the initial probe from the rest path")
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>

diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c
index 6cd9395ba9ec3d8044b4eaf0e6665c7d739d718d..9026a730d5ed8bcaa94016d5d65edbac8d5b9ba2 100644 (file)
--- a/drivers/nvme/host/pci.c
+++ b/drivers/nvme/host/pci.c
@@ -2508,6 +2508,12 @@ static unsigned int nvme_pci_nr_maps(struct nvme_dev *dev)
 
 static void nvme_pci_update_nr_queues(struct nvme_dev *dev)
 {
+       if (!dev->ctrl.tagset) {
+               nvme_alloc_io_tag_set(&dev->ctrl, &dev->tagset, &nvme_mq_ops,
+                               nvme_pci_nr_maps(dev), sizeof(struct nvme_iod));
+               return;
+       }
+
        blk_mq_update_nr_hw_queues(&dev->tagset, dev->online_queues - 1);
        /* free previously allocated queues that are no longer usable */
        nvme_free_queues(dev, dev->online_queues);