Btrfs has had its fair share of bugs, but rarely do they result in the inability to at least mount the file system read-only and get your data out. What has fur

Btrfs has had its fair share of bugs, but rarely do they result in the inability to at least mount the file system read-only and get your data out. What has further been exposed by Btrfs are device bugs, in particular firmware. When write ordering doesn't happen the way the file system expects, it's a big problem, and Btrfs does not tolerate them, it should abruptly go read only in order to prevent amplifying file system confusion. This is separate from silent data corruption which Btrfs also detects and complains about, but usually just results in EIO as Btrfs will not propagate data it think is corrupt due to csum mismatches. But even in that case you can get your data out.