There is a patch called blk_freeze which useful for owners of IBM/Lenovo ThinkPads and particular MacBooks. It can freeze a harddisks cache and send its head to the parking lot. This is useful if ones notebook provides a sensor for motions and a shock is estimated within the next second. This can save the data on the drive. The mentioned patch is needed for parking the head *without writing the data stored in the cache*. I would like to see the patch included in the official gentoo-sources. Are you willing to do so or do you have reasonable arguments for regretting to do so? Reproducible: Always A detailed How-To for APS on ThinkPads: http://www.thinkwiki.org/wiki/How_to_protect_the_harddisk_through_APS Where you find the actual patch: http://www.zen24593.zen.co.uk/hdaps/
See http://dev.gentoo.org/~dsd/genpatches/faq.htm
Some people are reporting a hang and the author states: "Don't use it, is the best suggestion for the time being." The author states he's working on it and to give him some time. And yes, it has not made the mainline kernel development tree.
Thanks for the suggestion, but we don't take non-upstream patches and Mike's findings indicate why :) Feel free to reopen if this makes it upstream in which case we can consider backporting it.