nvme: Don't suspend admin queue that wasn't created

This fixes a regression in my previous commit c21377f8366c ("nvme:
Suspend all queues before deletion"), which provoked an Oops in the
removal path when removing a device that became IO incapable very early
at probe (i.e. after a failed EEH recovery).

Turns out, if the error occurred very early at the probe path, before
even configuring the admin queue, we might try to suspend the
uninitialized admin queue, accessing bad memory.

Fixes: c21377f8366c ("nvme: Suspend all queues before deletion")
Signed-off-by: Gabriel Krisman Bertazi <krisman@linux.vnet.ibm.com>
Reviewed-by: Jay Freyensee <james_p_freyensee@linux.intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
(cherry picked from commit 82469c59d222f839ded5cd282172258e026f9112)

Orabug: 26486098

Signed-off-by: Ashok Vairavan <ashok.vairavan@oracle.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c
index 819249f416a42c267b1259fbdc63f36ba6f0ed6e..9411c6449837b66849a08d050f264781d2bf6f7b 100644 (file)
--- a/drivers/nvme/host/pci.c
+++ b/drivers/nvme/host/pci.c
@@ -1755,7 +1755,12 @@ static void nvme_dev_disable(struct nvme_dev *dev, bool shutdown)
                nvme_suspend_queue(dev->queues[i]);
 
        if (csts & NVME_CSTS_CFS || !(csts & NVME_CSTS_RDY)) {
-               nvme_suspend_queue(dev->queues[0]);
+               /* A device might become IO incapable very soon during
+                * probe, before the admin queue is configured. Thus,
+                * queue_count can be 0 here.
+                */
+               if (dev->queue_count)
+                       nvme_suspend_queue(dev->queues[0]);
        } else {
                nvme_disable_io_queues(dev, queues);
                nvme_disable_admin_queue(dev, shutdown);