Hi, I tried to test EROFS on Linux 5.4 as the root file system and mounted a writable overlay (with upper layer on tmpfs) over /etc, but I get ENODATA errors when attempting to modify files. For example, adding a user results in "Failed to take /etc/passwd lock: No data available". Files can be modified after unlinking and restoring them so they're created on the upper layer. This is not necessary with other read-only file systems (at least squashfs or ext4 with the read-only feature). I tried while forcing compact and extended inodes.
Is EROFS intended to be usable as a lower layer with overlayfs? Thanks. David
