By any chance will the following patch be able to get rid of
the warning ?
index 4560878f0bac..889555910555 100644
--- a/kernel/trace/blktrace.c
+++ b/kernel/trace/blktrace.c
@@ -1895,9 +1895,7 @@ static ssize_t sysfs_blk_trace_attr_store(struct
device *dev,
goto out_unlock_bdev;
}
- ret = 0;
- if (bt == NULL)
- ret = blk_trace_setup_queue(q, bdev);
+ ret = bt == NULL ? blk_trace_setup_queue(q, bdev) : 0;
if (ret == 0) {
if (attr == &dev_attr_act_mask)
On 03/02/2020 12:41 PM, Bjorn Helgaas wrote:
> On Thu, Feb 06, 2020 at 03:28:12PM +0100, Jan Kara wrote:
>
>> @@ -1844,18 +1896,18 @@ static ssize_t sysfs_blk_trace_attr_store(struct device *dev,
>> }
>>
>> ret = 0;
>> - if (q->blk_trace == NULL)
>> + if (bt == NULL)
>> ret = blk_trace_setup_queue(q, bdev);
>>
>> if (ret == 0) {
>> if (attr == &dev_attr_act_mask)
>> - q->blk_trace->act_mask = value;
>> + bt->act_mask = value;
>
> You've likely seen this already, but Coverity complains that "bt" may
> be a NULL pointer here, since we checked it for NULL above.
>
> CID 1460458: Null pointer dereferences (FORWARD_NULL)
>
>> else if (attr == &dev_attr_pid)
>> - q->blk_trace->pid = value;
>> + bt->pid = value;
>> else if (attr == &dev_attr_start_lba)
>> - q->blk_trace->start_lba = value;
>> + bt->start_lba = value;
>> else if (attr == &dev_attr_end_lba)
>> - q->blk_trace->end_lba = value;
>> + bt->end_lba = value;
>> }
>>
>> out_unlock_bdev:
>>
>
