Comment 11 for bug 1449005

I have the same problem. After updating my Evo 840 to firmware EXT0DB6Q I got a lot of read errors (kernel 3.16.0-37), but the smart status did not show any errors logged. I currently run this drive in an older Thinkpad X201. Interestingly I was able to boot the system partially but it got hung up due to read errors in the middle of the process.

As an initial workaround I switched the controller from AHCI to compatibility before I found this bug report. Then I was able to boot the system without problems.

Disabling the discard option in fstab made my system work in AHCI mode again. So I can definitely confirm it is related to trimming.