Here's what I've found using a very similar setup to Nikita and after receiving the same error messages.
> Any message after entering the password prompt? GRUB prints a single message "Slot 0 opened" and then it's into the kernel boot logs. The first related message appears to be the "ext2fs_check_if_mount..." one. > Perhaps you could try running ‘cryptsetup’ by hand from the REPL. I needed to replace "/bin/cryptsetup" with "/sbin/cryptsetup". After that, cryptsetup accepted a password and printed these errors: device-mapper: table 253:0: crypt: Error allocating crypto tfm device-mapper: ioctl: error adding target to table device-mapper: reload ioctl on failed: No such file or directory Failed to open temporary keystore device. device-mapper: remove ioctl on temporary-cryptsetup-149 failed: No such device or address The return value was 256, and afterwards /dev/mapper/main still did not exist.
