Re: WARNING: at drivers/ata/libata-core.c:5988 ata_qc_issue()

[Tejun Heo <htejun@gmail.com>]

Mark Lord wrote:
> Tejun Heo wrote:
>> Mark Lord wrote:
>>> Tejun,
>>>
>>> During testing with NCQ on sata_mv (patches coming shortly),
>>> I found this gem in the syslog.  This doesn't look like something
>>> that a LLD could cause, but rather a race perhaps in libata-core.
>>
>> Hmmm... This isn't supposed to happen.
>>
>>> System is a 2.4GHz 32-bit Core2Quad, 2GB RAM (during this test),
>>> running 2.6.24-rc6-git12 + newer sata_mv, with two sata_mv controller
>>> cards, each with one NCQ drive performing heavy R/W activity.
>>>
>>> Other than that, I'm not sure what triggered this.
>>
>> Can you please tell me which version you were using?  Or tell me which
>> one of the three WARN_ON()'s in ata_qc_issue() was triggered?  Thanks.
> ..
>>> [  289.892890] WARNING: at drivers/ata/libata-core.c:5988 ata_qc_issue()
> ..
> 
> The first one shown below, at drivers/ata/libata-core.c:5988:
> 
>> void ata_qc_issue(struct ata_queued_cmd *qc)
>> {
>>         struct ata_port *ap = qc->ap;
>>         struct ata_link *link = qc->dev->link;
>>
>>         /* Make sure only one non-NCQ command is outstanding.  The
>>          * check is skipped for old EH because it reuses active qc to
>>          * request ATAPI sense.
>>          */
> =         WARN_ON(ap->ops->error_handler &&

Hmm... Thanks.  Do you have your ->qc_defer set?

-- 
tejun