Followup: My email to Samsung clearly and succinctly stated that there is a bug in their firmware, where it wrongly reports "I support NCQ TRIM!" but it really doesn't, and that they introduced the bug recently. I said nothing about Linux.
Their mentally retarded response: "Dear Customer,
Thank you for contacting Samsung Support regarding your concerns and inquiries. We apologize for any inconvenience this may be causing you. Since Linux is open source, Samsung does not support the OS. All we can tell you is that you can disable Queued TRIM in Linux. Linux will then start using Sequential Trim, which is similar to how Windows does TRIM. Newer versions of Linux kernels blacklist the drive so that Queued TRIM automatically is disabled.
Thank you again for contacting Samsung Support and have a good day.
In other words: "Our product is broken, so just tell the OS not to use the broken feature and hey presto you're a winner! Now stop bugging us with your Loonixes and stuff."
Can we try to get press attention on this? Random corruption caused by regular TRIM operation is almost as serious as the 840 Evo's data retention issue.