Comment 81 for bug 569900

I'm having very similar simptoms after installing 10.04.1 from scratch
with two 500Gb disks (WD and ST).
The system installs and boots correctly if the raid1 array is created manually
from CLI before partitions detection.
But after some hours of uptime, errors start appearing in logs and the array becomes degraded:

Sep 19 13:36:19 deepthought kernel: [ 278.248022] ata3.00: qc timeout (cmd 0x27)
Sep 19 13:36:19 deepthought kernel: [ 278.248027] ata3.00: failed to read native max address (err_mask=0x4)
Sep 19 13:36:19 deepthought kernel: [ 278.248033] ata3.00: disabled
Sep 19 13:36:19 deepthought kernel: [ 278.248039] ata3.00: device reported invalid CHS sector 0
Sep 19 13:36:19 deepthought kernel: [ 278.248049] ata3: hard resetting link
Sep 19 13:36:20 deepthought kernel: [ 279.128035] ata3: SATA link up 1.5 Gbps (SStatus 113 SControl 310)
Sep 19 13:36:20 deepthought kernel: [ 279.128048] ata3: EH complete
Sep 19 13:36:20 deepthought kernel: [ 279.128057] sd 2:0:0:0: [sdb] Unhandled error code
Sep 19 13:36:20 deepthought kernel: [ 279.128059] sd 2:0:0:0: [sdb] Result: hostbyte=DID_BAD_TARGET driverbyte=DRIVER_OK
Sep 19 13:36:20 deepthought kernel: [ 279.128062] sd 2:0:0:0: [sdb] CDB: Write(10): 2a 00 3a 38 5f 88 00 00 08 00
Sep 19 13:36:20 deepthought kernel: [ 279.128082] md: super_written gets error=-5, uptodate=0
Sep 19 13:36:20 deepthought kernel: [ 279.128105] sd 2:0:0:0: [sdb] Unhandled error code
Sep 19 13:36:20 deepthought kernel: [ 279.128106] sd 2:0:0:0: [sdb] Result: hostbyte=DID_BAD_TARGET driverbyte=DRIVER_OK
Sep 19 13:36:20 deepthought kernel: [ 279.128109] sd 2:0:0:0: [sdb] CDB: Read(10): 28 00 06 a2 3c 80 00 00 20 00
Sep 19 13:36:20 deepthought kernel: [ 279.205366] RAID1 conf printout:
Sep 19 13:36:20 deepthought kernel: [ 279.205369] --- wd:1 rd:2
Sep 19 13:36:20 deepthought kernel: [ 279.205371] disk 0, wo:0, o:1, dev:sda
Sep 19 13:36:20 deepthought kernel: [ 279.205373] disk 1, wo:1, o:0, dev:sdb
Sep 19 13:36:20 deepthought kernel: [ 279.212009] RAID1 conf printout:
Sep 19 13:36:20 deepthought kernel: [ 279.212011] --- wd:1 rd:2
Sep 19 13:36:20 deepthought kernel: [ 279.212013] disk 0, wo:0, o:1, dev:sda

also in dmesg this message is present at every boot:

[ 3.022033] md1: p5 size 976269312 exceeds device capacity, limited to end of disk

These are the partitions as seen from sfdisk:

~$ sudo sfdisk -l /dev/sda

Disk /dev/sda: 30401 cylinders, 255 heads, 63 sectors/track
Warning: The partition table looks like it was made
  for C/H/S=*/81/63 (instead of 30401/255/63).
For this listing I'll assume that geometry.
Units = cylinders of 2612736 bytes, blocks of 1024 bytes, counting from 0

   Device Boot Start End #cyls #blocks Id System
/dev/sda1 0+ 95707- 95708- 244197560 83 Linux
  end: (c,h,s) expected (1023,80,63) found (705,80,63)
/dev/sda2 0 - 0 0 0 Empty
/dev/sda3 0 - 0 0 0 Empty
/dev/sda4 0 - 0 0 0 Empty

~$ sudo sfdisk -l /dev/sdb

Disk /dev/sdb: 60801 cylinders, 255 heads, 63 sectors/track
Warning: extended partition does not start at a cylinder boundary.
DOS and Linux will interpret the contents differently.
Units = cylinders of 8225280 bytes, blocks of 1024 bytes, counting from 0

   Device Boot Start End #cyls #blocks Id System
/dev/sdb1 0+ 31- 32- 249856 fd Linux raid autodetect
/dev/sdb2 31+ 60801- 60770- 488134657 5 Extended
/dev/sdb3 0 - 0 0 0 Empty
/dev/sdb4 0 - 0 0 0 Empty
/dev/sdb5 31+ 60801- 60770- 488134656 fd Linux raid autodetect

This is /proc/mdstat output instead:

Personalities : [linear] [multipath] [raid0] [raid1] [raid6] [raid5] [raid4] [raid10]
md0 : active raid1 sdc1[1] md1p1[0]
      249792 blocks [2/2] [UU]

md1 : active raid1 sdb[0]
      488134592 blocks [2/1] [U_]
      bitmap: 114/233 pages [456KB], 1024KB chunk

I'm at the third/fourth reinstall attempt (previously I've had the bad idea of using raid1+luks+lvm now I've
switchet to plaintext) but I'm still having stability issues.
Can somebody confirm whether I'm hitting this bug?