panic on 4.20 server exporting xfs filesystem

[Christoph Hellwig]

On Wed, Mar 04, 2015 at 03:41:41PM +1100, Dave Chinner wrote:
> As I understand it, nothing will prevent this - if you don't change
> the UUID on the filesystem when you clone it, then the UUID will
> still match and writes can be directed to any block deice with a
> matching offset/UUID pair.

Unfortunately that's the case indeed.  The whole discovery part of
the block layout protocol is fundamentally flawed, as is the recall
part.  This is my attempt to fix it, but I have no idea how to proceed
from posting my draft to the IETF to actually making it a standard:

http://tools.ietf.org/html/draft-hellwig-nfsv4-scsi-layout-00