Symptoms: OSX 10.10.2 crash while powering down the Thunderbolt storage or the eSATA devices on Thunderbolt Station 2.
Summary: Most of Thunderbolt storage devices take advantage of OSX’ inbox AHCI driver including the eSATA ports on Thunderbolt Station 2. It seems that 10.10.2’s AHCI driver is not working properly and would cause a system crash while you attempt to shut down storage.
If you run into a system crash while powering down your Thunderbolt storage devices or external eSATA storage, it is likely caused by the OSX inbox driver.
On the next OS restart, you may see the following message in the panic log:
Kernel Extensions in backtrace:
com.apple.driver.AppleAHCIPort(3.1)[93E1D2EC-50EE-3340-9676-0EA1E0B1AD45]@0xfff fff7f8f26b000->0xffffff7f8f285fff
This is caused by Apple’s OSX 10.10.2 inbox AHCI storage driver.
The temporary workaround would be the following:
1. If you plan to power off the Thunderbolt storage, always eject the Thunderbolt storage from desktop, then disconnect the Thunderbolt cable from the device. This workaround may prevent your OS from crashing in some Macs.
2. Roll back OSX to 10.10.1.
We expect Apple will have a fix in the next few OS revisions.
Additional Information:
https://discussions.apple.com/thread/6800125