Comment # 7 on bug 1033098 from zhilong liu

OS: 4.1.12-1-default (Leap 42.1)

  Reshape doesn't work after I patched the commit of "8e7ddc5f50af".

Steps:
1. osc checkout and branch the project to
home:zlliu:branches:openSUSE:Leap:42.1:Update/mdadm.
2. add the commit "8e7ddc5f50af" and rebuild.
3. replace the mdadm package.
cluster11:~/mdadm # mdadm -CR /dev/md0 -b internal -l1 -n2 /dev/loop1
/dev/loop2
cluster11:~/mdadm # mdadm --grow /dev/md0 -l5 -n3 -a /dev/loop3
mdadm: level of /dev/md0 changed to raid5
mdadm: added /dev/loop3
mdadm: Need to backup 128K of critical section..
mdadm: Cannot start reshape for /dev/md0
mdadm: aborting level change
unfreeze
cluster11:~/mdadm # dmesg -c
[  334.339269] md/raid:md0: device loop2 operational as raid disk 1
[  334.339273] md/raid:md0: device loop1 operational as raid disk 0
[  334.339452] md/raid:md0: allocated 2250kB
[  334.344096] md/raid:md0: raid level 5 active with 2 out of 2 devices,
algorithm 2
[  334.344098] RAID conf printout:
[  334.344099]  --- level:5 rd:2 wd:2
[  334.344100]  disk 0, o:1, dev:loop1
[  334.344101]  disk 1, o:1, dev:loop2
[  334.344113] md/raid456: discard support disabled due to uncertainty.
[  334.344114] Set raid456.devices_handle_discard_safely=Y to override.
[  334.580298] md: bind<loop3>
[  334.729490] md: could not open unknown-block(7,3).
[  334.729527] md: md_import_device returned -16
[  335.056265] md/raid1:md0: active with 2 out of 2 mirrors
[  335.056692] md: could not open unknown-block(7,3).
[  335.056729] md: md_import_device returned -16
[  335.238767] RAID1 conf printout:
[  335.238772]  --- wd:2 rd:2
[  335.238774]  disk 0, wo:0, o:1, dev:loop1
[  335.238775]  disk 1, wo:0, o:1, dev:loop2

Thanks,
-Zhilong