I have found conflicting answers to this around the web, even a link to a launchpad bug: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/571476 which is kind of left hanging.
So I'm curious, was TRIM support backported into the 2.6.32 kernel that is in 10.04? Does anyone know for sure?
Edit Although the above Launchpad Bug is relevant, it's this bug that is linked from the last comment on the above one that is most relevant: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/644694
In this, for Lucid update to 184.108.40.206 stable release there is listed under: The following patches are in the 220.127.116.11 stable release: * sata_mv: fix broken DSM/TRIM support (v2)