Comment 16 for bug 1449005

It may not be necessary to disable NCQ completely, but only for the
TRIM command. The 3.16.0 kernel apparently already contains a blacklist of
devices for which TRIM together with NCQ causes trouble. It is located
in the file:

drivers/ata/libata-core.c

Could anyone, who has already applied the firmware update, plece try
to add an entry like the follwoing to the array ata_device_blacklist in the above file?

{ "Samsung SSD 840 EVO *", NULL, ATA_HORKAGE_NO_NCQ_TRIM, }

On boot, the resulting kernel should say something like the following
for the 840 EVO:

"disabling queued TRIM support"