scsi: ufs: core: Fix divide by zero in ufshcd_map_queues()

Before calling blk_mq_map_queues(), the mq_map and nr_queues belonging to
struct blk_mq_queue_map must have a valid value.

If nr_queues is set to 0, the system may encounter a divide by zero
depending on the type of architecture.

    blk_mq_map_queues() -> queue_index()

Link: https://lore.kernel.org/r/1891546521.01644873481638.JavaMail.epsvc@epcpadp4
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Jinyoung Choi <j-young.choi@samsung.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 50b12d6..9349557 100644 (file)
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -2681,7 +2681,7 @@ static int ufshcd_map_queues(struct Scsi_Host *shost)
                        break;
                case HCTX_TYPE_READ:
                        map->nr_queues = 0;
-                       break;
+                       continue;
                default:
                        WARN_ON_ONCE(true);
                }