MD/RAID: what's wrong with sector 1953519935?

["Andrei Tanas" <andrei@tanas.ca>]

Hello,

I'm using two ST31000528AS drives in RAID1 array using MD. I've had several
failures occur over a period of few months (see logs below). I've RMA'd the
drive, but then got curious why an otherwise normal drive locks up while
trying to write the same sector once a month or so, but does not report
having bad sectors, doesn't fail any tests, and does just fine if I do
dd if=/dev/urandom of=/dev/sdb bs=512 seek=1953519935 count=1
however many times I try.
I then tried Googling for this number (1953519935) and found that it comes
up quite a few times and most of the time (or always) in context of md/raid.
So my question is: is it just a coincidence (doesn't seem to be likely for a
number this big), or is it possible that when sent to hard drive, it gets
interpreted like some command and sends the drive into some unpredictable
state?

I will gladly provide any additional info that might be necessary.


#smartctl -i /dev/sdb
=== START OF INFORMATION SECTION ===
Device Model:     ST31000528AS
Serial Number:    6VP01LNL
Firmware Version: CC34
User Capacity:    1,000,204,886,016 bytes
Device is:        Not in smartctl database [for details use: -P showall]
ATA Version is:   8
ATA Standard is:  ATA-8-ACS revision 4
Local Time is:    Thu Aug 20 10:52:31 2009 EDT
SMART support is: Available - device has SMART capability.
SMART support is: Enabled

----------------------------------------------------
Jul 27 19:02:31 srv kernel: [901292.247428] ata2.00: exception Emask 0x0
SAct 0x0 SErr 0x0 action 0x6 frozen
Jul 27 19:02:31 srv kernel: [901292.247492] ata2.00: cmd
ea/00:00:00:00:00/00:00:00:00:00/a0 tag 0
Jul 27 19:02:31 srv kernel: [901292.247494]          res
40/00:01:01:4f:c2/00:00:00:00:00/00 Emask 0x4 (timeout)
Jul 27 19:02:31 srv kernel: [901292.247500] ata2.00: status: { DRDY }
Jul 27 19:02:31 srv kernel: [901292.247512] ata2: hard resetting link
Jul 27 19:02:33 srv kernel: [901294.090746] ata2: SRST failed (errno=-19)
Jul 27 19:02:33 srv kernel: [901294.101922] ata2: SATA link up 3.0 Gbps
(SStatus 123 SControl 300)
Jul 27 19:02:33 srv kernel: [901294.101938] ata2.00: failed to IDENTIFY (I/O
error, err_mask=0x40)
Jul 27 19:02:33 srv kernel: [901294.101943] ata2.00: revalidation failed
(errno=-5)
Jul 27 19:02:38 srv kernel: [901299.100347] ata2: hard resetting link
Jul 27 19:02:38 srv kernel: [901299.974103] ata2: SATA link up 3.0 Gbps
(SStatus 123 SControl 300)
Jul 27 19:02:39 srv kernel: [901300.105734] ata2.00: configured for UDMA/133
Jul 27 19:02:39 srv kernel: [901300.105776] ata2: EH complete
Jul 27 19:02:39 srv kernel: [901300.137059] end_request: I/O error, dev sdb,
sector 1953519935
Jul 27 19:02:39 srv kernel: [901300.137069] md: super_written gets error=-5,
uptodate=0
Jul 27 19:02:39 srv kernel: [901300.137077] raid1: Disk failure on sdb1,
disabling device.
Jul 27 19:02:39 srv kernel: [901300.137079] raid1: Operation continuing on 1
devices.
Jul 27 19:02:39 srv kernel: [901300.208812] RAID1 conf printout:
Jul 27 19:02:39 srv kernel: [901300.208820]  --- wd:1 rd:2
Jul 27 19:02:39 srv kernel: [901300.208826]  disk 0, wo:0, o:1, dev:sda1
Jul 27 19:02:39 srv kernel: [901300.208830]  disk 1, wo:1, o:0, dev:sdb1
Jul 27 19:02:39 srv kernel: [901300.217392] RAID1 conf printout:
Jul 27 19:02:39 srv kernel: [901300.217399]  --- wd:1 rd:2
Jul 27 19:02:39 srv kernel: [901300.217404]  disk 0, wo:0, o:1, dev:sda1

Aug 20 00:15:36 srv kernel: [90307.328266] ata2.00: exception Emask 0x0 SAct
0x0 SErr 0x0 action 0x6 frozen
Aug 20 00:15:36 srv kernel: [90307.328275] ata2.00: cmd
ea/00:00:00:00:00/00:00:00:00:00/a0 tag 0
Aug 20 00:15:36 srv kernel: [90307.328277]          res
40/00:01:01:4f:c2/00:00:00:00:00/00 Emask 0x4 (timeout)
Aug 20 00:15:36 srv kernel: [90307.328280] ata2.00: status: { DRDY }
Aug 20 00:15:36 srv kernel: [90307.328288] ata2: hard resetting link
Aug 20 00:15:47 srv kernel: [90313.218511] ata2: link is slow to respond,
please be patient (ready=0)
Aug 20 00:15:47 srv kernel: [90317.377711] ata2: SRST failed (errno=-16)
Aug 20 00:15:47 srv kernel: [90317.377720] ata2: hard resetting link
Aug 20 00:15:47 srv kernel: [90318.251720] ata2: SATA link up 3.0 Gbps
(SStatus 123 SControl 300)
Aug 20 00:15:47 srv kernel: [90318.338026] ata2.00: configured for UDMA/133
Aug 20 00:15:47 srv kernel: [90318.338062] ata2: EH complete
Aug 20 00:15:47 srv kernel: [90318.370625] end_request: I/O error, dev sdb,
sector 1953519935
Aug 20 00:15:47 srv kernel: [90318.370632] md: super_written gets error=-5,
uptodate=0
Aug 20 00:15:47 srv kernel: [90318.370636] raid1: Disk failure on sdb1,
disabling device.
Aug 20 00:15:47 srv kernel: [90318.370637] raid1: Operation continuing on 1
devices.
Aug 20 00:15:47 srv kernel: [90318.396403] RAID1 conf printout:
Aug 20 00:15:47 srv kernel: [90318.396408]  --- wd:1 rd:2
Aug 20 00:15:47 srv kernel: [90318.396410]  disk 0, wo:0, o:1, dev:sda1
Aug 20 00:15:47 srv kernel: [90318.396413]  disk 1, wo:1, o:0, dev:sdb1
Aug 20 00:15:47 srv kernel: [90318.429178] RAID1 conf printout:
Aug 20 00:15:47 srv kernel: [90318.429185]  --- wd:1 rd:2
Aug 20 00:15:47 srv kernel: [90318.429189]  disk 0, wo:0, o:1, dev:sda1