Sai Prakash Ranjan saiprakash.ranjan@codeaurora.org writes:
"Consider a system where disk contents are encrypted and the encryption key is set up by the user when mounting the file system. From that point on the encryption key resides in the kernel. It seems reasonable to expect that the disk encryption key be protected from exfiltration even if the system later suffers a root compromise (or even against insiders that have root access), at least as long as the attacker doesn't manage to compromise the kernel."
Normally disk encryption is in specialized work queues. It's total overkill to restrict all of the kernel if you just want to restrict those work queues.
I would suggest some more analysis where secrets are actually stored and handled first.
-Andi