My company produces Android devices running Linux 3.4 and we have seen that sometimes but rarely a file on the ext4 emmc file system will suddenly become zero-length. Normally I would suspect an improper shutdown while the file was being written but in this situation I know that this file is written once at first boot and never written again; although it is read at every boot.
Is anyone aware of a bug in ext4 code that could cause this? It seems that ext4 is still under quite a bit of active development. Maybe some sys-admins out there have encountered this and are aware of patch or version of the kernel that has a fix?