Curtain of death

Question

iMac12,2 - 3.4 GHz, Intel Core i7 - Randomly and without warning, a black transparent curtain descends from the top of the screen to the bottom and all input devices are blocked. A message in five languages appears in the middle of the screen. The message says "You need to restart your computer. Hold down the power button until the machine turns off then push the power button to restart." This has occurred ~10 time since purchasing the machine about a month ago. The events are logged, this is the last one:Sat May 28 09:42:10 2011panic(cpu 4 caller 0xffffff80002d1208): Kernel trap at 0xffffff800020df49, type 14&#x3D;page fault, registers:CR0: 0x0000000080010033, CR2: 0xffffff7f253ab2e8, CR3: 0x00000003c5dee000, CR4: 0x0000000000040660RAX: 0x0000000000000000, RBX: 0x0000000000000000, RCX: 0x00000000f9000000, RDX: 0xffffff8004f8a660RSP: 0xffffff8153803d40, RBP: 0xffffff8153803e20, RSI: 0x0000000000000001, RDI: 0xffffff8004f8a660R8:  0x00000000000000c8, R9:  0x0000000000000001, R10: 0x0000000000000006, R11: 0x0000000000000000R12: 0xffffff80005d3850, R13: 0xffffff8026cb4430, R14: 0xffffff8004f8a650, R15: 0xffffff7f253ab2e8RFL: 0x0000000000010212, RIP: 0xffffff800020df49, CS:  0x0000000000000008, SS:  0x0000000000000010Error code: 0x0000000000000000Backtrace (CPU 4), Frame : Return Address0xffffff81538039e0 : 0xffffff8000204d15 0xffffff8153803ae0 : 0xffffff80002d1208 0xffffff8153803c30 : 0xffffff80002e3f4a 0xffffff8153803c40 : 0xffffff800020df49 0xffffff8153803e20 : 0xffffff8000472697 0xffffff8153803e90 : 0xffffff80004737f5 0xffffff8153803ed0 : 0xffffff80004b46bf 0xffffff8153803f40 : 0xffffff80004e8158 0xffffff8153803fa0 : 0xffffff80002e4874 BSD process name corresponding to current thread: launchdMac OS version:10J4138Kernel version:Darwin Kernel Version 10.7.4: Mon Apr 18 21:24:17 PDT 2011; root:xnu-1504.14.12~3/RELEASE_X86_64System model name: iMac12,2 (Mac-942B59F58194171B)System uptime in nanoseconds: 109959168582485unloaded kexts:com.apple.driver.AppleUSBUHCI          4.2.0 (addr 0xffffff7f8134b000, size 0x65536) - last unloaded 127434086810loaded kexts:com.parallels.kext.prl_vnic          6.0 11994.637263 - last loaded 30245912192com.parallels.kext.prl_netbridge          6.0 11994.637263com.parallels.kext.prl_usb_connect          6.0 11994.637263com.parallels.kext.prl_hid_hook          6.0 11994.637263com.parallels.kext.prl_hypervisor          6.0 11994.637263at.obdev.nke.LittleSnitch          2.3.19com.metakine.handsoff.driver          1.2.2com.apple.driver.AppleBluetoothMultitouch          54com.apple.filesystems.autofs          2.1.0com.apple.driver.AGPM          100.12.31com.apple.driver.AppleHWSensor          1.9.3d0com.apple.driver.AudioAUUC          1.57com.apple.driver.AppleMikeyHIDDriver          1.2.0com.apple.Dont_Steal_Mac_OS_X          7.0.0com.apple.driver.AudioIPCDriver          1.1.6com.apple.driver.AppleUpstreamUserClient          3.5.7com.apple.driver.AppleMCCSControl          1.0.20com.apple.driver.AppleHDA          2.0.5f13com.apple.driver.AppleMikeyDriver          2.0.5f13com.apple.kext.ATIFramebuffer          6.3.4com.apple.ATIRadeonX3000          6.3.4com.apple.driver.AirPort.Atheros9388          426.35.3com.apple.driver.ACPI_SMC_PlatformPlugin          4.7.0a1com.apple.driver.AppleLPC          1.5.1com.apple.driver.AppleBacklight          170.0.46com.apple.kext.AppleSMCLMU          1.5.2d10com.apple.driver.AppleIntelHDGraphics          6.3.4com.apple.driver.AppleIntelSNBGraphicsFB          6.3.4com.apple.driver.AppleIRController          303.8com.apple.driver.AppleUSBCardReader          2.6.0com.apple.iokit.SCSITaskUserClient          2.6.8com.apple.driver.Oxford_Semi          2.6.0com.apple.BootCache          31com.apple.AppleFSCompression.AppleFSCompressionTypeZlib          1.0.0d1com.apple.iokit.IOAHCIBlockStorage          1.6.4com.apple.driver.AppleFWOHCI          4.7.3com.apple.driver.AppleUSBHub          4.2.0com.apple.iokit.AppleBCM5701Ethernet          3.0.5b8com.apple.driver.AppleEFINVRAM          1.4.0com.apple.driver.AppleAHCIPort          2.1.7com.apple.driver.AppleUSBEHCI          4.2.0com.apple.driver.AppleACPIButtons          1.3.6com.apple.driver.AppleRTC          1.3.1com.apple.driver.AppleHPET          1.5com.apple.driver.AppleSMBIOS          1.7com.apple.driver.AppleACPIEC          1.3.6com.apple.driver.AppleAPIC          1.4com.apple.driver.AppleIntelCPUPowerManagementClient          142.6.0com.apple.security.sandbox          1com.apple.security.quarantine          0com.apple.nke.applicationfirewall          2.1.11com.apple.driver.AppleIntelCPUPowerManagement          142.6.0com.apple.driver.AppleBluetoothHIDKeyboard          141com.apple.driver.AppleHIDKeyboard          141com.apple.driver.IOBluetoothHIDDriver          2.4.5f1com.apple.driver.AppleMultitouchDriver          207.11com.apple.driver.AppleProfileReadCounterAction          17com.apple.driver.AppleProfileTimestampAction          10com.apple.driver.AppleProfileThreadInfoAction          14com.apple.driver.AppleProfileRegisterStateAction          10com.apple.driver.AppleProfileKEventAction          10com.apple.driver.AppleProfileCallstackAction          20com.apple.iokit.IOSurface          74.2com.apple.iokit.IOBluetoothSerialManager          2.4.5f1com.apple.iokit.IOSerialFamily          10.0.3com.apple.driver.DspFuncLib          2.0.5f13com.apple.iokit.IOAudioFamily          1.8.3fc2com.apple.kext.OSvKernDSPLib          1.3com.apple.driver.AppleSMBusController          1.0.10d0com.apple.kext.ATI6000Controller          6.3.4com.apple.kext.ATISupport          6.3.4com.apple.iokit.IOFireWireIP          2.0.3com.apple.driver.AppleHDAController          2.0.5f13com.apple.iokit.IOHDAFamily          2.0.5f13com.apple.iokit.IO80211Family          320.1com.apple.iokit.AppleProfileFamily          41com.apple.driver.IOPlatformPluginFamily          4.7.0a1com.apple.driver.AppleSMBusPCI          1.0.10d0com.apple.driver.AppleBacklightExpert          1.0.1com.apple.driver.AppleSMC          3.1.0d5com.apple.driver.AppleThunderboltEDMSink          1.0.5com.apple.driver.AppleThunderboltEDMSource          1.0.5com.apple.iokit.IONDRVSupport          2.2com.apple.iokit.IOGraphicsFamily          2.2com.apple.driver.AppleThunderboltDPOutAdapter          1.2.0com.apple.driver.AppleThunderboltDPInAdapter          1.2.0com.apple.driver.AppleThunderboltDPAdapterFamily          1.2.0com.apple.driver.AppleThunderboltPCIDownAdapter          1.1.5com.apple.driver.BroadcomUSBBluetoothHCIController          2.4.5f1com.apple.driver.AppleUSBBluetoothHCIController          2.4.5f1com.apple.iokit.IOBluetoothFamily          2.4.5f1com.apple.iokit.IOSCSIMultimediaCommandsDevice          2.6.8com.apple.iokit.IOBDStorageFamily          1.6com.apple.iokit.IODVDStorageFamily          1.6com.apple.iokit.IOCDStorageFamily          1.6.1com.apple.iokit.IOUSBHIDDriver          4.2.0com.apple.iokit.IOAHCISerialATAPI          1.2.6com.apple.iokit.IOUSBMassStorageClass          2.6.6com.apple.iokit.IOSCSIBlockCommandsDevice          2.6.8com.apple.iokit.IOFireWireSerialBusProtocolTransport          2.1.0com.apple.iokit.IOSCSIArchitectureModelFamily          2.6.8com.apple.iokit.IOFireWireSBP2          4.0.6com.apple.driver.AppleUSBMergeNub          4.2.2com.apple.driver.AppleUSBComposite          3.9.0com.apple.driver.XsanFilter          402.1com.apple.driver.AppleThunderboltNHI          1.2.3com.apple.iokit.IOThunderboltFamily          1.3.5com.apple.iokit.IOFireWireFamily          4.2.6com.apple.iokit.IOUSBUserClient          4.2.0com.apple.iokit.IONetworkingFamily          1.10com.apple.iokit.IOAHCIFamily          2.0.6com.apple.iokit.IOUSBFamily          4.2.2com.apple.driver.AppleEFIRuntime          1.4.0com.apple.iokit.IOHIDFamily          1.6.6com.apple.iokit.IOSMBusFamily          1.1com.apple.kext.AppleMatch          1.0.0d1com.apple.security.TMSafetyNet          6com.apple.driver.DiskImages          289com.apple.iokit.IOStorageFamily          1.6.3com.apple.driver.AppleACPIPlatform          1.3.6com.apple.iokit.IOPCIFamily          2.6.3com.apple.iokit.IOACPIFamily          1.3.0

Miron_2005 · Answer

Got almost the same trouble. But have to forget of any support coz here in Ukraine its hard to find competent sellers. My imac hangs because of adobe premiere. Ppl say even skype could hang an imac. Its not exactly the answer you expected but , you know, ypu are not alone. ))))

Kappy · Answer

You have several third-party extensions installed that could be at the root of the kernel panics.  Parallels, LittleSnitch, and something called "handsoff driver."  I suggest that as a start you uninstall the software associated with these extensions.  Also disconnect any third-party peripherals that use the USB ports other than your keyboard and/or mouse.If the kernel panics stop then one or more of the third-party items referred to above are causing the kernel panics.  To determine which are complicit you will need to install only one of them at a time.  Test the system to see that there are no panics occurring (I would start with Parallels.)  If all is well add another one, etc.  Frankly, I&#x27;d avoid LittleSnitch since it is frequently associated with kernel panics, but this is up to you.Also, visit The XLab FAQs and read the FAQ on diagnosing kernel panics.If you want to test what will happen with all third-party extensions disabled but without having to uninstall software, then boot into Safe Mode. Safe mode will disable all third-party extensions as well as some system extensions.  In particular your wireless will be disabled.  Operate in safe mode for a day or so to see if this eliminates kernel panics.

Rick Lang · Answer

Excellent advice from Kappy!  If that doesn’t work, try this.It’s a kernel panic and it should not appear of course.  Sorry I don’t know what is causing the kernel panic in your situation but you should have called Apple about it the first time or two it happened as you may have a ‘bad’ machine.You can try to diagnose the problem by running an Apple Hardware Test.  When you call Apple they’ll ask you to run it so you can save time by doing it now:Insert your Install DVD into the optical drive,Shutdown the iMac,Start the iMac and quickly hold down the ‘D’ key until you find you are in the Apple Harwdare test application,You’ll see options to run a quick test but better a more extensive test (it takes longer).Your problem could be simply related to memory that is not completely reliable or problems related to the circuit board.I think I’ve had this happen a couple of times in the last year and a half.  But ten times in a month is not acceptable and your machine may be dying.  Ensure you have complete backups.

2dm · Answer

Thanks Rick and Kappy. I&#x27;ve got a little diagnostic work to do before I call Apple. I forgot to mention that I replaced the original 4 GB of factory RAM with 16 GB of OWC RAM before I plugged the machine in for the first time. I&#x27;ve got Drive Genius installed on an external HD so I can run the diagnostics from that as well. Thanks again for the great advice.Don

Paul_31 · Answer

Hi Don, there are several threads on here of people experiencing problems when running 16gb of RAM. The problem is usually random shutdowns although some have reported kernel panics. It seems that the manufacturer of the installed RAM can make a difference - Samsung RAM seems to be problem free, if I recall correctly.It might be worth taking some of the RAM out and running on 12gb as this seems to be a fix for many. If it does prove to be a solution I believe OWC are very good at swapping the RAM for another make without making life difficult.

2dm · Answer

Hi Paul,That&#x27;s very helpful, thank you. I just ran the hardware diagnostics from the install disc and there were no problems detected. Kappy suggested uninstalling third-party programs that might be the source of the problem. If that fails, I&#x27;ll call OWC and seek a remedy through them. You&#x27;re right, OWC has great customer service. Thanks again for the assistance.Don

maximium · Answer

com.parallels.kext.prl_vnic          6.0 11994.637263 - last loaded 30245912192com.parallels.kext.prl_netbridge          6.0 11994.637263com.parallels.kext.prl_usb_connect          6.0 11994.637263com.parallels.kext.prl_hid_hook          6.0 11994.637263com.parallels.kext.prl_hypervisor          6.0 11994.637263I see a lot of problems caused by Parallels Software.Here too: https://discussions.apple.com/thread/3067784?answerId&#x3D;15270001022#15270001022&searchText&#x3D;kernel%20panic%2010.7. 4%20parallels#15270001

maximium · Answer

I have OWC memory. 16GB of it on MBP 8.1 i5.But since I updated to 10.7.4 I haven&#x27;t got any problems until I ran Parallels Desktop 6.Had the same KP and report as 2dm user.

maximium · Answer

So, I passed Memory Test done by TechTools Pro 5 successfully!16GB of those OWC RAM in my i5 MBP 8.1All the tests passed.It&#x27;s not abot the RAM.

Miron_2005 · Answer

We may test whatever we like but the fact is when I downgraded to 8Gb I got no visual loss at speed - and forgot about curtain of death.Good Luck!

maximium · Answer

Maybe you&#x27;re right.But I installed this 2x8GB memory modules about 2 weeks ago.Then updated to 10.7.4 and worked on it from the day of release (over 5-6 days long).And in both cases with no issues. As smooth as it can be.My opinion is still the troubles caused either by third-party software or the problem is in 10.7.4 update.We&#x27;ll see.

maximium · Answer

Maybe Parallels Desktop can&#x27;t address such a volume of memory?Who knows?

Kappy · Answer

It&#x27;s more likely because you need to use Parallels 7.x for compatibility.

maximium · Answer

Nope, I&#x27;ve found in other threads same problems, but caused by version 7*)

Kappy · Answer

I use Parallels 7 on all my Lion machines without any such problems. In most, if not all, cases panics will be caused by a bad extension or an incompatibility between third-party extensions and Mac or other third-party extensions. Sometimes this can be fixed simply by upgrading the third-party software if the current versions are not what the user has installed. Other times you simply can&#x27;t use a third-party software because of incompatibility with other third-party software even though each works fine when not running with the other.Some software that should be considered carefully include anti-virus software, running another VM product concurrently with Parallels (or VM Fusion,) some versions of Little Snitch, some audio software/hardware, incompatible older versions of mouse and keyboard softrware. These are typical but not all inclusive.Running in Safe Mode disables third-party extensions which can help determine if the panics can be isolated to a third-party extension or plug-in (preference pane, bad Flash, input handler, etc.)