On Tue, Sep 1, 2020 at 9:01 PM Mauro Condarelli <mc5686@xxxxxxxxx> wrote: > > Hi, > most likely this is not the right place to ask, please redirect me as needed. > > I'm trying to use OverlayFS to add (limited) write capability to a ReadOnly > rootfs (SquashFS) > > Essentially (actual script is more complex, of course) boot-sequence includes: > > # /dev/mmcblk0p5: ext4 (upper+work+nwwroot+newroot/oldroot) > # /dev/mmcblk0p6: SquashFS mounted on / > mount /dev/mmcblk0p5 /overlay > mount -t overlay overlay -o lowerdir=/,upperdir=/overlay/upper,workdir=/overlay/work /overlay/newroot > cd /overlay/newroot > pivot_root . oldroot > mount --move oldroot/dev /dev > mount --move oldroot/proc /proc > > This works as expected, but, too often for comfort, some file > (and sometime also directories) become unavailable due to error: > > overlayfs: invalid origin (ssh/sshd_config, ftype=8000, origin ftype=4000). > > File name changes, of course, but rest is fairly constant. > > This always happens when some file is written. > Error persists reboots. > Only way I found to "cure" the system is to go on "upper" and delete the file > thus going back to "lower" version (in this case I should delete "/oldroot/overlay/upper/etc/ssh/sshd_config") > > This is a self-built kernel (Linux vocore 5.7.0 #2 PREEMPT Mon Aug 3 09:19:06 CEST 2020 mips GNU/Linux) > on a custom target based on a SoC (MT7628). > > I am available to do any required test, but I have no idea about where to start. > > Any hint (or redirect) would be greatly appreciated. This is probably your problem: https://lore.kernel.org/linux-unionfs/32532923.JtPX5UtSzP@fgdesktop/ If it is, it should be solved by commit a888db310195 ovl: fix regression with re-formatted lower squashfs in upstream kernel v5.9-rc1 or in stable kernel >= 5.7.10. Thanks, Amir.
