Oracle's hands are tied in so far as they can't revoke the CDDL licence that Sun provided. They could sue you as a kernel contributor, but only if you do somet

Oracle's hands are tied in so far as they can't revoke the CDDL licence that Sun provided. They could sue you as a kernel contributor, but only if you do something to violate the GPL. The only thing that would clearly violate the GPL, in the era of proprietary nvidia blobs, is if you tried to ship the ZFS source code in-tree. Everybody agrees that's a bad idea, nobody does it. ZFS instead is shipped as a separate kernel module.