Hello Shaohua Li,
This is a semi-automatic email about new static checker warnings.
The patch 2984c8684f96: "nullb: factor disk parameters" from Aug 14,
2017, leads to the following Smatch complaint:
drivers/block/null_blk.c:1759 null_init_tag_set()
error: we previously assumed 'nullb' could be null (see line 1750)
drivers/block/null_blk.c
1749 set->ops = &null_mq_ops;
1750 set->nr_hw_queues = nullb ? nullb->dev->submit_queues :
1751 g_submit_queues;
1752 set->queue_depth = nullb ? nullb->dev->hw_queue_depth :
1753 g_hw_queue_depth;
1754 set->numa_node = nullb ? nullb->dev->home_node : g_home_node;
^^^^^
The patch introduces a series of new NULL checks
1755 set->cmd_size = sizeof(struct nullb_cmd);
1756 set->flags = BLK_MQ_F_SHOULD_MERGE;
1757 set->driver_data = NULL;
1758
1759 if (nullb->dev->blocking)
^^^^^^^^^^^^^^^^^^^^
And an unchecked dereference.
1760 set->flags |= BLK_MQ_F_BLOCKING;
1761
regards,
dan carpenter
