It was safe to rename() a file and expect the data it contained after crash to either be (1) the data before the rename(), (2) the data after the rename(). What changing the ext4 default logging mode to "data=writeback" did is add two more options, (3) nothing (0 bytes), and (4) whatever random garbage it found on disk, potentially including a copy of /etc/shadow. No-one misread the docs, the behavior changed.
But hey, if you're angling to be hired by a YC-funded storage startup, this is certainly a post.
But hey, if you're angling to be hired by a YC-funded storage startup, this is certainly a post.