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Bcachefs: Better handling of checksum errors/bitrot

by koverstreet on 3/11/25, 9:09 PM with 3 comments

  • by yencabulator on 3/11/25, 11:24 PM

    > - - And, moving said extent requires giving it a new checksum [...]

    > - Extents need a poison bit: "reads return errors, even though it now has a good checksum" - this was added in a separate patch queued up for 6.15.

    To me, it sounds like saving the old hash could be useful. That way a human can look at the now-corrupt extent, test flipping that one odd-looking bit, and confirm that the extent now matches the old hash.

    So poison bit => failing_hash: Option<Hash>

  • by asdffdasy on 3/11/25, 9:59 PM

    i am barely catching up to btrfs