On Fri 2021-07-09 (19:06), Lord Vader wrote:

On Fri, 9 Jul 2021 at 01:18, Ulli Horlacher
[off-list ref] wrote:

quoted

I have waited some time and some Ubuntu updates, but the bug is still there:

quoted

quoted

When I try to access a btrfs filesystem via nfs, I get the error:
root@tsmsrvi:~# mount tsmsrvj:/data/fex /nfs/tsmsrvj/fex
root@tsmsrvi:~# time find /nfs/tsmsrvj/fex | wc -l
find: File system loop detected; '/nfs/tsmsrvj/fex/spool' is part of the same file system loop as '/nfs/tsmsrvj/fex'.

Can you try exporting NFS share with 'crossmnt' option?

root@tsmsrvj:/etc# exportfs -v
/data/fex       localhost.localdomain(rw,async,wdelay,crossmnt,no_root_squash,no_subtree_check,sec=sys,rw,secure,no_root_squash,no_all_squash)

root@tsmsrvj:/etc# mount -v localhost:/data/fex /nfs/localhost/fex
mount.nfs: timeout set for Sat Jul 10 09:02:31 2021
mount.nfs: trying text-based options 'vers=4.2,addr=127.0.0.1,clientaddr=127.0.0.1'

root@tsmsrvj:/etc# du -s /nfs/localhost/fex
du: WARNING: Circular directory structure.
This almost certainly means that you have a corrupted file system.
NOTIFY YOUR SYSTEM MANAGER.
The following directory is part of the cycle:
  /nfs/localhost/fex/spool

-- 
Ullrich Horlacher              Server und Virtualisierung
Rechenzentrum TIK         
Universitaet Stuttgart         E-Mail: horlacher@tik.uni-stuttgart.de
Allmandring 30a                Tel:    ++49-711-68565868
70569 Stuttgart (Germany)      WWW:    http://www.tik.uni-stuttgart.de/
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