> the key can be generated and then used to encrypt the disk
Right, you can't recover or copy that specific key, but you also don't have to for accessing your data, if you set up some redundancy before disaster struck.
AFAIK: 99% of your storage is encrypted by a giant fixed unchanging master-key, and that is itself encrypted again with a non-master key/LS or passphrase, which is stored in the remaining "LUKS header". There's room to store multiple copies of the same master-key encrypted with different non-master options.
In that model, the TPM is simply providing (in a convoluted way) its own passphrase for one of those co-equal slots, so having one or more alternates prepared is sufficient to protect your drive from motherboard failure.
Right, you can't recover or copy that specific key, but you also don't have to for accessing your data, if you set up some redundancy before disaster struck.
AFAIK: 99% of your storage is encrypted by a giant fixed unchanging master-key, and that is itself encrypted again with a non-master key/LS or passphrase, which is stored in the remaining "LUKS header". There's room to store multiple copies of the same master-key encrypted with different non-master options.
In that model, the TPM is simply providing (in a convoluted way) its own passphrase for one of those co-equal slots, so having one or more alternates prepared is sufficient to protect your drive from motherboard failure.