Re: Linux 2.6.24-rc7

["J.A. Magallón" <jamagallon@ono.com>]

On Thu, 10 Jan 2008 22:10:08 +0900, Tejun Heo <htejun@gmail.com> wrote:

> Hi,
> 
> J.A. Magallón wrote:
> > It reproduces also with 2.6.23.13.
> > Finally I think the problematic disk is sdc:
> 
> Okay, then, it's less likely a regression and more likely a newly
> developed hardware problem.
> 
> > ICH5 PATA -> sda
> > ICH5 SATA0 -> sdb
> > ICH5 SATA1 -> sdc
> > Promise SATA -> sdd
> > 
> > The problem is that even I have commented out the entry for sdc in fstab,
> > the system is still giving me errors. An my guess is that errors in sdc makes
> > the ICH5 sata controller go nuts, and then I get errors also in sdb.
> > Just a couple questions...
> 
> I've never seen ICHs or any other SATA controllers act that way.
> 
> > - Can I say to ata_piix something like 'please, detect first SATA ports before
> >   ATA', so my system disk (sdb) becomes sda ?
> 
> You do that using LABEL, UUID or device ID.  Just run 'ls -l
> /dev/disk/by-*/' and see the result.
> 
> > - Can I say 'plz, ignore port 1', so it does not try to detect/start/spin sdc ?
> >   So I ban be sure it is the one to blame, before start to remove hardware...
> 
> Unfortunately not but you can boot into single mode where there's
> nothing trying to access the disk without your explicit command and
> verify access to each hard disk.
> 
> Hmm... You are seeing timeouts from multiple harddisks.  The first thing
> I would try is to reseat the cables and connect the SATA hard drives to
> a separate power supply and see whether that changes anything.
> 

I'm still pending to pysically remove the disks (or at least unplug the
cable...), but I have realized a cusious thing: after some errors, the
kernel is lowering the disk speed (UDMA/133, then 100, then 33):

ata3.00: exception Emask 0x0 SAct 0x0 SErr 0x0 action 0x2 frozen
ata3.00: cmd c8/00:08:07:81:3f/00:00:00:00:00/e0 tag 0 dma 4096 in
         res 40/00:00:00:00:00/00:00:00:00:00/00 Emask 0x4 (timeout)
ata3.00: status: { DRDY }
ata3: soft resetting link
ata3.00: configured for UDMA/133
ata3: EH complete
...
ata3.00: exception Emask 0x0 SAct 0x0 SErr 0x0 action 0x2 frozen
ata3.00: cmd c8/00:48:05:73:33/00:00:00:00:00/ef tag 0 dma 36864 in
         res 40/00:00:00:00:00/00:00:00:00:00/00 Emask 0x4 (timeout)
ata3.00: status: { DRDY }
ata3: soft resetting link
ata3.00: configured for UDMA/133
ata3: EH complete
...
(one more 133)
...
ata3.00: limiting speed to UDMA/100:PIO4
ata3.00: exception Emask 0x0 SAct 0x0 SErr 0x0 action 0x2 frozen
ata3.00: cmd c8/00:40:8d:9c:84/00:00:00:00:00/eb tag 0 dma 32768 in
         res 40/00:00:00:00:00/00:00:00:00:00/00 Emask 0x4 (timeout)
ata3.00: status: { DRDY }
ata3: soft resetting link
ata3.00: configured for UDMA/100
...
(3 more 100)
...
ata3.00: limiting speed to UDMA/33:PIO4
ata3.00: exception Emask 0x0 SAct 0x0 SErr 0x0 action 0x2 frozen
ata3.00: cmd ca/00:08:9f:00:1a/00:00:00:00:00/e2 tag 0 dma 4096 out
         res 40/00:00:00:00:00/00:00:00:00:00/00 Emask 0x4 (timeout)
ata3.00: status: { DRDY }
ata3: soft resetting link
ata3.00: configured for UDMA/33
...

Perhaps this gives a clue.
Or I just had bad luck and 2 of my 4 disks broke at the same time.

--
J.A. Magallon <jamagallon()ono!com>     \               Software is like sex:
                                         \         It's better when it's free
Mandriva Linux release 2008.1 (Cooker) for i586
Linux 2.6.23-jam05 (gcc 4.2.2 20071128 (4.2.2-2mdv2008.1)) SMP PREEMPT