Hi all > Can you be a bit more verbose in your explanation?
OK, I try: live-boot in Debian 9 uses overlayfs per default instead of aufs in Debian 8. One difference between aufs and overlayfs is that aufs can operate directly on the file system root but overlayfs needs certain subdirectories (rw and work) on the file system root. Here is a quote from https://www.kernel.org/doc/Documentation/filesystems/overlayfs.txt: -------------------- The "workdir" needs to be an empty directory on the same filesystem as upperdir. -------------------- This fact was partly taken care of in live-boot in the script 9990-misc-helpers.sh, see here: https://anonscm.debian.org/cgit/debian-live/live-boot.git/tree/components/9990-misc-helpers.sh#n1335 The important part here is the postfix "/rw" in the option "upperdir=${unionrw}/rw" Unfortunately, these subtleties of overlayfs were not taken into account when using it as a lower layer (when you add the boot option "persistence-read-only"). This is what my patch fixes. > How can we reproduce the problem? Create a Debian Live system with a persistence partition, use it first in normal "read-write" mode and change some files and settings. Then reboot and use the boot option "persistence-read-only". You will see that non of your previous changes are visible because the persistence partition got mounted the wrong way (without the "/rw" postfix). > Why is your patch fixing the issue? Because it correctly mounts the persistence partition in the overlayfs case including the necessary "/rw" postfix. Cheers Ronny