As a short update, I can confirm that when run with the default options, pvcreate initializes the first 512 bytes of the LVM header block with 0x00, similarly to ext4, creating excellent known plaintext that is easy to spot during debugging of decryption routines. This is documented in the manpage of pvcreate: "-Z, --zero {y|n} Whether or not the first 4 sectors (2048 bytes) of the device should be wiped. If this option is not given, the default is to wipe these sectors unless either or both of the --restorefile or --uuid options were specified." https://linux.die.net/man/8/pvcreate My current memcmp of the first 512 bytes therefore works just as well on LVM as on ext4 and has managed to find a bit flip on a deliberately corrupted key slot. However, this is bad news for my ultimate target of recovering the actual master key of the SSD in question, as it seems my previous 1-error checks have been unsuccessful, but valid. Regards, protagonist _______________________________________________ dm-crypt mailing list dm-crypt@xxxxxxxx http://www.saout.de/mailman/listinfo/dm-crypt