Hello, I think that I have found a regression/bug on overlayfs. I can't get NFS lowerdir working with Linux 4.4 even though it's supported without custom patching. It worked with Linux 4.1 with little custom patching (see link below). How to reproduce: * Compile Linux 4.4 or any revision which is newer than "Commit 4bacc9 overlayfs: Make f_path always point to the overlay and f_inode to the underlay" * Mount nfs with default options (my share is exported with (rw,sync,no_subtree_check)) * Mount overlay with nfs as lowerdir * Try to read any existing file on overlayfs Example: # uname -r 4.3.0-1-amd64 # mkdir /tmp/nfs /tmp/upper /tmp/work /tmp/merge # mount -o defaults 192.168.1.9:/home/shared /tmp/nfs # mount -t overlay overlay -olowerdir=/tmp/nfs,upperdir=/tmp/upper,workdir=/tmp/work /tmp/merge # mount | grep "/tmp" 192.168.1.9:/home/shared on /tmp/nfs type nfs4 (rw,relatime,vers=4.0,rsize=524288,wsize=524288,namlen=255,hard,proto=tcp,port=0,timeo=600,retrans=2,sec=sys,clientaddr=192.168.1.15,local_lock=none,addr=192.168.1.9) overlay on /tmp/merge type overlay (rw,relatime,lowerdir=/tmp/nfs,upperdir=/tmp/upper,workdir=/tmp/work) # echo hello >/tmp/nfs/hello # cat /tmp/merge/hello cat: /tmp/merge/hello: No such device or address I think my issue is same than: http://www.spinics.net/lists/linux-unionfs/msg00386.html NFS works as lowerdir without 4bacc9 (linux 4.1 for example) when nfs lowerdir is allowed by patching fs/overlayfs/super.c@692 See http://www.spinics.net/lists/linux-unionfs/msg00188.html for details. Best Regards Jussi -- To unsubscribe from this list: send the line "unsubscribe linux-unionfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
