ad0: TIMEOUT - WRITE_DMA retrying (2 retries left) LBA=xxx

Ken Smith kensmith at cse.Buffalo.EDU
Thu Sep 30 19:58:59 PDT 2004

On Thu, Sep 30, 2004 at 07:54:31PM -0600, Scott Long wrote:
> Tristan wrote:
> >On Fri, 1 Oct 2004 03:28:38 +0200
> >Marius Strobl <marius at> wrote:
> >>On Thu, Sep 30, 2004 at 08:52:27PM -0400, Ken Smith wrote:
> >>>On Fri, Oct 01, 2004 at 09:35:15AM +0930, Tristan wrote:
> >>>>FreeBSD 6.0-CURRENT with GENERIC kernel built 27th Sep.
> >>>>On a SunBlade 100 I see these messages regularly when
> >>>>dma is enabled. The messages go away when I either use
> >>>>atacontrol to set the mode to PIO4 or set hw.ata.ata_dma to 0
> >>>>I do get data corruption on the disk if left in DMA mode.
> >>>
> >>>Just FYI my primary test machine is a SunBlade 100, it seems to
> >>>be doing OK with a kernel built from this morning's source.  I've
> >>>been doing most of my builds from an NFS server though, I'll do
> >>>a check with a full buildworld which will use the local drive more.
> >>>
> >>>>ad0: 14594MB <ST315310A/3.28> [29651/16/63] at ata2-master UDMA66
> >>>>acd0: CDRW <LTN486S/YSU1> at ata2-slave PIO4
> >>>>ata3-master: DMA limited to UDMA33, non-ATA66 cable or device
> >>>>ad1: 39266MB <IBM-DTLA-305040/TW4OA60A> [79780/16/63] at ata3-master 
> >>>>UDMA33
> >>>>Mounted root from ufs:/dev/ad0a.
> Detaching the CDROM would be an easy first test.  The CDROM is likely
> wanting to use WDMA mode which itself can be problematic (and is why
> FreeBSD turns it off by default).

Just for reference, this is pieces from a machine I've got here
that doesn't *seem* to be having problems:

FreeBSD 6.0-CURRENT #0: Thu Sep 30 09:54:31 EDT 2004
    kensmith at

atapci0: <AcerLabs Aladdin UDMA66 controller> port 0xa20-0xa2f,0xa08-0xa0b,0xa10-0xa17,0xa18-0xa1b,0xa00-0xa07 at device 13.0 on pci0
ata2: channel #0 on atapci0
ata3: channel #1 on atapci0
pcib1: <OFW PCI-PCI bridge> at device 5.0 on pci0
pci1: <OFW PCI bus> on pcib1
pci0: <display, VGA> at device 19.0 (no driver attached)
Timecounters tick every 10.000 msec
ad0: 19092MB <ST320011A/3.10> [38792/16/63] at ata2-master UDMA66
acd0: CDRW <LTN486S/Y3S2> at ata2-slave UDMA33
Mounted root from ufs:/dev/ad0a.

						Ken Smith
- From there to here, from here to      |       kensmith at
  there, funny things are everywhere.   |
                      - Theodore Geisel |

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