Hi Follow-up for the issue. I stuck with this "invalid csum for free space extent" error. Could anyone explain what does it mean? If this is not data and just a free space, why do we care about its checksum? And if we do really care then btrfs should have a way to fix this error. I can "fix" a file checksum error by removing the file, but how to "fix" free space extent checksum error? I decided to run --init-csum-tree to see if it fixes the issue with free space csum. I expected that it will recalculate csum for data. And found that it cleared csum tree completely and made my fs became unusable. Any read returns csum error. The data is still on disk - I can read it with filefrag+btrfs-map-logic+dd - it is just csum information that got dropped. So I want to echo the request from Robin http://www.spinics.net/lists/linux-btrfs/msg25271.html Information about --init-csum-tree should be documented. What is the use-case for this feature? In fact I expected that it will recalculate the csum tree based on the data, not clear the tree. So I endup with reinstalling my system and copying data from backups. Despite all my complains I still think btrfs is a great filesystem. I really enjoy their multi-device support that allows me to use all my different HDDs that I have. Thanks for your work, everyone! -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
