Comment # 28 on bug 1043912 from Nikolay Borisov

(In reply to Frederic Crozat from comment #26)
> I just upgraded my Leap 42.2 system to the latest kernel-default from
> maintenance update ( 4.4.74-18.20-default ) and problem is still there:
> 
> [    7.052652] BTRFS info (device sdb1): disk space caching is enabled
> [    7.060731] BTRFS error (device sdb1): super_total_bytes 1000203816960
> mismatch with fs_devices total_rw_bytes 1000203820544
> [    7.060733] BTRFS error (device sdb1): failed to read chunk tree: -22
> [    7.110461] BTRFS error (device sdb1): open_ctree failed
> 
> I look like the fix didn't make it or isn't properly applied

So can yo perform the following steps: 

1. Boot your system with the last kernel I provided you with:
https://build.suse.de/project/show/home:nikbor:bsc1043912

2. You should be able to mount the system and will likely see the warnings your
described before. 

3. Run btrfs balance as before - this time you shouldn't see the warnings. At
this point I'm expecting to see rounded-down values stored on disk. To verify
this again provide a dump of the super block and the device tree for the
affected partition with those 2 commands: 

btrfs inspect-internal dump-super -af /dev/vdb
btrfs inspect-internal dump-tree -d /dev/vdb