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Level 1

27 points

iMac crashes when powering off external Thunderbolt drive

Hi,

I have an external LaCie d2 USB 3.0 drive that is connect to my iMac (27-inch, Mid 2011, 3,1 GHz Intel Core i5, 12 GB RAM) through Thunderbolt. Whenever I power off the drive by pushing the power button (yes I did verify: all partitions have been ejected correctly before in the Finder and verified in Disk Utility), the iMac crashes. It starts up again, displays a screen stating the computer was not shut down properly and then immediately restarts. After that it boots up fine.

This started occurring after having installed 10.10.2 Beta. I did file a report with Apple. As this was beta software I decided to completely reinstall the iMac from scratch (a complete fresh install, just imported my documents manually after) and everything was working fine again (10.10.1). Boom, after having updated 10.10.2 yesterday the problem is back.

I did manage to find a workaround: when I connect the drive through a UBS cable it works fine. Conclusion: this seems to be caused by a Thunderbolt related update in 10.10.2.

Question: is any one else with an external Thunderbolt drive experiencing this and has perhaps found a fix?

Thanks,

Kurt

Wed Jan 28 16:30:36 2015

*** Panic Report ***

panic(cpu 0 caller 0xffffff800341a46e): Kernel trap at 0xffffff80038e9774, type 14=page fault, registers:

CR0: 0x000000008001003b, CR2: 0x0000000000000000, CR3: 0x00000000066ee000, CR4: 0x00000000000626e0

RAX: 0x0000000000070001, RBX: 0xffffff8036919c00, RCX: 0x8883c87675b70011, RDX: 0xffffff81541e9088

RSP: 0xffffff817bb0be90, RBP: 0xffffff817bb0be90, RSI: 0xffffff81541e9068, RDI: 0x0000000000000000

R8: 0x0000000000987482, R9: 0xffffff8003a95740, R10: 0x000017d7912af429, R11: 0x000017d790927fa7

R12: 0xffffff817bb0bf50, R13: 0xffffff7f85328044, R14: 0xffffff7f8533e978, R15: 0xffffff8003ad66c0

RFL: 0x0000000000010202, RIP: 0xffffff80038e9774, CS: 0x0000000000000008, SS: 0x0000000000000010

Fault CR2: 0x0000000000000000, Error code: 0x0000000000000000, Fault CPU: 0x0

Backtrace (CPU 0), Frame : Return Address

0xffffff817bb0bb40 : 0xffffff800332fe41

0xffffff817bb0bbc0 : 0xffffff800341a46e

0xffffff817bb0bd80 : 0xffffff8003436683

0xffffff817bb0bda0 : 0xffffff80038e9774

0xffffff817bb0be90 : 0xffffff7f85328267

0xffffff817bb0beb0 : 0xffffff7f8532bad7

0xffffff817bb0bee0 : 0xffffff7f853281ed

0xffffff817bb0bf00 : 0xffffff80033624f9

0xffffff817bb0bfb0 : 0xffffff8003414dd7

Kernel Extensions in backtrace:

com.apple.driver.AppleAHCIPort(3.1)[93E1D2EC-50EE-3340-9676-0EA1E0B1AD45]@0xfff fff7f85324000->0xffffff7f8533efff

dependency: com.apple.iokit.IOAHCIFamily(2.7.5)[DAF0353B-16D5-385A-A0F3-FD5CF3BA07F2]@0xfff fff7f84706000

dependency: com.apple.iokit.IOPCIFamily(2.9)[56AD16B5-4F29-3F74-93E7-D492B3966DE2]@0xffffff 7f83b24000

BSD process name corresponding to current thread: kernel_task

Mac OS version:

14C109

Kernel version:

Darwin Kernel Version 14.1.0: Mon Dec 22 23:10:38 PST 2014; root:xnu-2782.10.72~2/RELEASE_X86_64

Kernel UUID: DCF5C2D5-16AE-37F5-B2BE-ED127048DFF5

Kernel slide: 0x0000000003000000

Kernel text base: 0xffffff8003200000

__HIB text base: 0xffffff8003100000

System model name: iMac12,2

iMac, Mac OS X (10.2.x) , null

Posted on Jan 28, 2015 7:50 AM

Best reply

odie1234

Level 1

0 points

Posted on Jan 28, 2015 11:59 AM

I have the same issue. Disk is ejected properly and I go to power it off and I get a re-boot and then the white screen.

View in context

54 replies

holtynq

Level 1

31 points

Feb 4, 2015 4:54 AM in response to holtynq

Appropriate feedback sent to Apple, I rolled back to 10.10.1 with no further issue.

krenders Author

Level 1

27 points

Feb 4, 2015 7:34 AM in response to Stephan-S

Thx, I am going to send them my feedback as well!

Question: why do you restart in Recovery mode? I would think it is faster to shut down, power down the drive and then start again. Or during a restart power it down at the exact same moment the iMac restarts (when the screen goes black and there is a typical noise when the internal hard disk spins down).

Feb 4, 2015 1:11 PM in response to krenders

Question: why do you restart in Recovery mode? I would think it is faster to shut down, power down the drive and then start again. Or during a restart power it down at the exact same moment the iMac restarts (when the screen goes black and there is a typical noise when the internal hard disk spins down).

Good point! No particular reason, actually. I only use that drive temporarily (for occasional video editing) then go on using my iMac, so what came to my mind was rebooting to go on with my stuff, not shutting down the system. Of course!

lohlita

Level 1

0 points

Feb 7, 2015 12:54 AM in response to holtynq

Feedback sent to Apple. I'm also getting a kernel panic and OS reboot when powering down an external Thunderbolt RAID device on my system:

-iMac Retina 5k

-OWC Thunderbay 4

-OSX Yosemite 10.10.2

Feb 7, 2015 3:07 AM in response to Stephan-S

I logged a ticket and called Apple Care customer service. They don't seem to be aware of Thunderbolt issues with OS X 10.10.2, and their only suggestion was to reset the PRAM [reboot with ctr-alt-P-R] and reset the SMC [shut down, disconnect, hold power switch for 10 seconds]. This didn't change anything, except that maybe the kernel panic was even more 'panicked' than before, as there would be no error message (just a blank grey screen), and it wasn't able to write a log. But it's probably just coincidental.

I also asked if there's any driver that I could revert to its previous version from my Time Machine backups, but they had no answer on that.

May I suggest that those of you, who might happen to have a valid Apple Care subscription still ongoing, would still call them and log a ticket? I wouldn't expect a solution in the short term, but as the saying goes, "if you don't ask you shouldn't expect anything" and customer care still is a formal channel to report our problems.

Kind regards,

Feb 7, 2015 3:28 AM in response to Stephan-S

Has anyone tried the latest beta-update of Yosemite? It's beta, so beware.

Feb 7, 2015 10:27 AM in response to Stephan-S

Unmount drives, remove thunderbolt cable.. Then power off drive.. Make will stay running.. Then plug back in.

power on.

Feb 7, 2015 10:33 AM in response to wswalton

unplug the thunderbolt cable from unit before powering off as a workaround.

Feb 7, 2015 10:43 AM in response to garyfromlos gatos

My LaCies can't be shut down when unplugged. They remain in sleep, until the cable is plugged in again and it appears on the desktop again.

Feb 8, 2015 2:10 AM in response to garyfromlos gatos

garyfromlos gatos wrote:

Unmount drives, remove thunderbolt cable.. Then power off drive.. Make will stay running.. Then plug back in.

power on.

I would kindly advise against that. I once unplugged / plugged a Thunderbolt unit while my iMac was on, and there were tiny sparks when the Thunderbolt plug touched the iMac frame (ground loop!) - then as I was plugging the cable in, the iMac abruptly shut itself off with no warning (boom; no panic screen, no reboot, just off and blank screen). Moment of fright, then after a minute I was able to turn the iMac on again, eventually.

Ground loops are dangerous, this reminds me of the countless horror stories that used to happen with Firewire ports. People thought Firewire was hot-plug (it was from a software standpoint, but the electrical circuits weren't), resulting in expensive camcorders getting "fried ports" beyond simple repair. So now with Thunderbolt I'm taking the same precautions I used to take with Firewire (with no issue): if the device comes with its own power, I first shut down the iMac, disconnect all power cords from the wall outlets, connect Thunderbolt, reconnect power, and boot. This doesn't apply to bus-powered drives, of course.

Sorry for drifting slightly off topic, back to the OS X 10.10.2 issue now, but I thought you might want to know about possible risks of suffering a ground loop.

Kind regards,