What you call "pathologic" cases when it comes to real-world data are very common. It is not at all unusual to find sectors filled with only a constant (usually zero, but not always), in which case your **512 becomes **1.
Of course it would be easy to check how many of the 512 Bytes are really different on a case-by-case basis and correct the exponent accordingly, and only perform the recovery when the corrected probability of introducing an error is sufficiently low.
Kind regards, Thiemo Nagel - To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
