xfs v5

[Elan Ruusamäe]

On 13.11.2015 17:01, Elan Ruusamäe wrote:
> can we go back to v4 or at least detect running kernel  first?
>
>
>    XFS Version v5 superblock VS old kernels ( < v3.15) issues
>
> Using recent Th provided xfsprogs|mkfs.xfs|results in created 
> filesystem with v5 superblock which is not fully supported in 3.14 and 
> lower kernels. Below message is produced in kernel log while trying to 
> mount such filesystem on old kernel (3.14):
>
> [3180866.360834] XFS (dm-13): Version 5 superblock detected. This 
> kernel has EXPERIMENTAL support enabled!
>                  Use of these features in this kernel is at your own 
> risk!
> [3180866.360848] XFS (dm-13): Superblock has unknown read-only 
> compatible features (0x1) enabled.
> [3180866.360853] XFS (dm-13): Attempted to mount read-only compatible 
> filesystem read-write.
>                  Filesystem can only be safely mounted read only.
> [3180866.360868] XFS (dm-13): SB validate failed with error 22.
>
> To overcome it and create v4 superblock, one need to provide 
> specific|mkfs.xfs|options to disable v5 features:
>
> mkfs.xfs -m crc=0,finobt=0 /dev/sys/apus-vserver
>
> See related issue 
> discussion:http://oss.sgi.com/archives/xfs/2015-08/msg00548.html

and more specifically:
http://oss.sgi.com/archives/xfs/2015-08/msg00554.html


-- 
glen