bug report: mdadm-devel-2 , superblock version 1

[Tyler <pml@dtbb.net>]

# uname -a
Linux server 2.6.12.3 #3 SMP Sun Jul 17 14:38:12 CEST 2005 i686 GNU/Linux
# ./mdadm -V
mdadm - v2.0-devel-2 - DEVELOPMENT VERSION NOT FOR REGULAR USE - 7 July 2005

root@server:~/dev/mdadm-2.0-devel-2# ./mdadm -S /dev/md1

** stop the current array

root@server:~/dev/mdadm-2.0-devel-2# ./mdadm -C /dev/md1 -l 5 
--raid-devices 3 -e 1 /dev/sda2 /dev/sdb2 /dev/sdc2
mdadm: /dev/sda2 appears to be part of a raid array:
    level=5 devices=3 ctime=Mon Jul 18 03:22:05 2005
mdadm: /dev/sdb2 appears to be part of a raid array:
    level=5 devices=3 ctime=Mon Jul 18 03:22:05 2005
mdadm: /dev/sdc2 appears to be part of a raid array:
    level=5 devices=3 ctime=Mon Jul 18 03:22:05 2005
Continue creating array? y
mdadm: array /dev/md1 started.

** create and start new array using 3 drives, superblock version 1

root@server:~/dev/mdadm-2.0-devel-2# cat /proc/mdstat
Personalities : [raid5]
md1 : active raid5 sdc2[3] sdb2[1] sda2[0]
      128384 blocks level 5, 64k chunk, algorithm 2 [3/3] [UUU]

unused devices: <none>

** mdstat mostly okay, except sdc2 is listed as device3 instead of 
device2 (from 0,1,2)

root@server:~/dev/mdadm-2.0-devel-2# ./mdadm -D /dev/md1
/dev/md1:
        Version : 01.00.01
  Creation Time : Mon Jul 18 03:56:40 2005
     Raid Level : raid5
     Array Size : 128384 (125.40 MiB 131.47 MB)
    Device Size : 64192 (62.70 MiB 65.73 MB)
   Raid Devices : 3
  Total Devices : 3
Preferred Minor : 1
    Persistence : Superblock is persistent

    Update Time : Mon Jul 18 03:56:42 2005
          State : clean
 Active Devices : 3
Working Devices : 3
 Failed Devices : 0
  Spare Devices : 0

         Layout : left-symmetric
     Chunk Size : 64K

           UUID : 1baa875e87:9ec208b2:7f5e6a27:db1f5e
         Events : 1

    Number   Major   Minor   RaidDevice State
       0       8        2        0      active sync   /dev/.static/dev/sda2
       1       8       18        1      active sync   /dev/.static/dev/sdb2
       2       0        0        -      removed

       3       8       34        2      active sync   /dev/.static/dev/sdc2

** reports version 01.00.01 superblock, but reports as if there were 4 
devices used

root@server:~/dev/mdadm-2.0-devel-2# ./mdadm -S /dev/md1

** stop the array

root@server:~/dev/mdadm-2.0-devel-2# ./mdadm -A /dev/md1
Segmentation fault

** try to assemble the array

root@server:~/dev/mdadm-2.0-devel-2# ./mdadm -D /dev/md1
mdadm: md device /dev/md1 does not appear to be active.

** check if its active at all

root@server:~/dev/mdadm-2.0-devel-2# ./mdadm -A /dev/md1 /dev/sda2 
/dev/sdb2 /dev/sdc2
mdadm: device 1 in /dev/md1 has wrong state in superblock, but /dev/sdb2 
seems ok
mdadm: device 2 in /dev/md1 has wrong state in superblock, but /dev/sdc2 
seems ok
mdadm: /dev/md1 has been started with 3 drives.

** try restarting it with drive details, and it starts

root@server:~/dev/mdadm-2.0-devel-2# ./mdadm -D /dev/md1
/dev/md1:
        Version : 00.90.01
  Creation Time : Mon Jul 18 02:53:55 2005
     Raid Level : raid5
     Array Size : 128384 (125.40 MiB 131.47 MB)
    Device Size : 64192 (62.70 MiB 65.73 MB)
   Raid Devices : 3
  Total Devices : 3
Preferred Minor : 1
    Persistence : Superblock is persistent

    Update Time : Mon Jul 18 02:53:57 2005
          State : clean
 Active Devices : 3
Working Devices : 3
 Failed Devices : 0
  Spare Devices : 0

         Layout : left-symmetric
     Chunk Size : 64K

           UUID : e798f37d:baf98c2f:e714b50c:8d1018b1
         Events : 0.2

    Number   Major   Minor   RaidDevice State
       0       8        2        0      active sync   /dev/.static/dev/sda2
       1       8       18        1      active sync   /dev/.static/dev/sdb2
       2       8       34        2      active sync   /dev/.static/dev/sdc2

** magically, we now have a v00.90.01 superblock, it reports the proper 
list of drives

root@server:~/dev/mdadm-2.0-devel-2# ./mdadm -S /dev/md1
root@server:~/dev/mdadm-2.0-devel-2# ./mdadm -A /dev/md1
Segmentation fault

** try to stop and restart again, doesn't work

root@server:~/dev/mdadm-2.0-devel-2# ./mdadm -E /dev/sda2
/dev/sda2:
          Magic : a92b4efc
        Version : 01.00
     Array UUID : 1baa875e87:9ec208b2:7f5e6a27:db1f5e
           Name :
  Creation Time : Mon Jul 18 03:56:40 2005
     Raid Level : raid5
   Raid Devices : 3

    Device Size : 128504 (62.76 MiB 65.79 MB)
   Super Offset : 128504 sectors
          State : clean
    Device UUID : 1baa875e87:9ec208b2:7f5e6a27:db1f5e
    Update Time : Mon Jul 18 03:56:42 2005
       Checksum : 903062ed - correct
         Events : 1

         Layout : left-symmetric
     Chunk Size : 64K

   Array State : Uuu 1 failed

** the drives themselves still report a version 1 superblock... wierd