On a machine using ICH6 SATA and nbd, I just got this from the current git
HEAD (e3f749c4af69c4344d89f11e2293e3790eb4eaca):
nbd: registered device at major 43
Badness in blk_do_ordered at block/ll_rw_blk.c:550
Call Trace: <IRQ> <ffffffff801e6414>{blk_do_ordered+753}
<ffffffff801e25e8>{elv_next_request+36} <ffffffff80287b7b>{scsi_request_fn+120}
<ffffffff801e4597>{blk_run_queue+48} <ffffffff801e653e>{bar_end_io+0}
<ffffffff80286feb>{scsi_next_command+46} <ffffffff802870e3>{scsi_end_request+192}
<ffffffff8028733b>{scsi_io_completion+452} <ffffffff802a089e>{sd_rw_intr+544}
<ffffffff80286d67>{scsi_device_unbusy+85} <ffffffff80287afe>{scsi_softirq_done+212}
<ffffffff801e5feb>{blk_done_softirq+123} <ffffffff8012ed48>{__do_softirq+80}
<ffffffff8010bb46>{call_softirq+30} <ffffffff8010d415>{do_softirq+47}
<ffffffff8010d3dc>{do_IRQ+62} <ffffffff80108f01>{mwait_idle+0}
<ffffffff8010aea4>{ret_from_intr+0} <EOI> <ffffffff80108f37>{mwait_idle+54}
<ffffffff80108ee2>{cpu_idle+98} <ffffffff8053a7a5>{start_kernel+434}
<ffffffff8053a286>{_sinittext+646}
Anyone else seeing this?
-ben