wrong --detail --test

[Constantine Shulyupin]

Degradation in 3.2 to 3.3.4, last working 3.2.6.

mdadm --detail --test returns 0 on for degraded array, when only the second of two disks is removed, works as expected when the first disk removed.

Expected:
  --test -t : exit status 0 if ok, 1 if degrade, 2 if dead, 4 if missing

Expected:
mdadm --detail /dev/md2 --test ; echo $?
/dev/md2:
        Version : 1.2
  Creation Time : Thu Dec 10 11:50:20 2015
     Raid Level : raid1
     Array Size : 780226240 (744.08 GiB 798.95 GB)
  Used Dev Size : 780226240 (744.08 GiB 798.95 GB)
   Raid Devices : 2
  Total Devices : 1
    Persistence : Superblock is persistent

  Intent Bitmap : Internal

    Update Time : Thu Dec 10 11:50:22 2015
          State : active, degraded
 Active Devices : 1
Working Devices : 1
 Failed Devices : 0
  Spare Devices : 0

           Name : A1
           UUID : 333592b4:40d92ae2:9cf82398:b92d466e
         Events : 24

    Number Major Minor RaidDevice State
       0 0 0 0 removed
       1 8 34 1 active sync /dev/sdc2
1
^^ not a bug

Bug:

mdadm --detail /dev/md1 --test ; echo $?
/dev/md1:
        Version : 1.2
  Creation Time : Thu Dec 10 11:39:41 2015
     Raid Level : raid1
     Array Size : 780226240 (744.08 GiB 798.95 GB)
  Used Dev Size : 780226240 (744.08 GiB 798.95 GB)
   Raid Devices : 2
  Total Devices : 1
    Persistence : Superblock is persistent

  Intent Bitmap : Internal

    Update Time : Thu Dec 10 11:42:35 2015
          State : active, degraded
 Active Devices : 1
Working Devices : 1
 Failed Devices : 0
  Spare Devices : 0

           Name : A1
           UUID : 6a29c716:b804f9f3:3519867f:32f98380
         Events : 32

    Number Major Minor RaidDevice State
       0 8 18 0 active sync /dev/sdb2
       2 0 0 2 removed
0
^^^ BUG