Sophos Causing Mac OS Abort/Restarts

I have been experiencing one, or two kernel panics a week for awhile. The version of Sophos I am running is 9.2.4 and is currently up to date. I am running OS X 10.10.3 on a MacBook Pro (3,1) with a 240GB (69GB Free) SSD and 6GB of ram. I have included 2 reports from kernel panics. Every time I have a kernel panic the backtrace info indicates the only extension is "com.sophos.kext.sav". Anonymous UUID: 6F14766E-A2BA-ED2A-7C99-8A8ABEEAAB13 Tue Feb 24 15:05:06 2015 *** Panic Report *** panic(cpu 1 caller 0xffffff80053427ab): "vnode_rele_ext: vp 0xffffff80155d6690 usecount -ve : -1. v_tag = 16, v_type = 1, v_flag = 84800."@/SourceCache/xnu/xnu-2782.10.72/bsd/vfs/vfs_subr.c:1867 Backtrace (CPU 1), Frame : Return Address 0xffffff80d4e5af30 : 0xffffff800512fe41 0xffffff80d4e5afb0 : 0xffffff80053427ab 0xffffff80d4e5aff0 : 0xffffff7f8581958f 0xffffff80d4e5b010 : 0xffffff7f85818de2 0xffffff80d4e5b360 : 0xffffff7f8581ae94 0xffffff80d4e5b3a0 : 0xffffff800559fc76 0xffffff80d4e5b400 : 0xffffff8005548499 0xffffff80d4e5bab0 : 0xffffff8005542559 0xffffff80d4e5bbd0 : 0xffffff8005370cb6 0xffffff80d4e5bc60 : 0xffffff800536037e 0xffffff80d4e5bd70 : 0xffffff8005356c08 0xffffff80d4e5bf50 : 0xffffff800564b386 0xffffff80d4e5bfb0 : 0xffffff8005236e86 Kernel Extensions in backtrace: com.sophos.kext.sav(9.2.50)[D9AF65D9-4A18-3B20-86BB-17DEBC7D5852]@0xffffff7f85818000->0xffffff7f8581cfff BSD process name corresponding to current thread: mds 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: 0x0000000004e00000 Kernel text base: 0xffffff8005000000 __HIB text base: 0xffffff8004f00000 System model name: MacBookPro3,1 (Mac-F42388C8) System uptime in nanoseconds: 79233380116253 last loaded kext at 1122295005226: com.apple.filesystems.msdosfs 1.10 (addr 0xffffff7f8779a000, size 69632) last unloaded kext at 1284978076728: com.apple.iokit.IOUSBMassStorageClass 3.7.1 (addr 0xffffff7f87775000, size 69632) loaded kexts: com.sophos.kext.sav 9.2.50 com.sophos.nke.swi 9.2.50 com.apple.filesystems.smbfs 3.0.0 com.apple.filesystems.afpfs 11.0 com.apple.nke.asp-tcp 8.0.0 com.apple.driver.AudioAUUC 1.70 com.apple.driver.AppleHWSensor 1.9.5d0 com.apple.filesystems.autofs 3.0 com.apple.iokit.IOBluetoothSerialManager 4.3.2f6 com.apple.driver.AppleOSXWatchdog 1 com.apple.driver.AppleHDA 269.25 com.apple.iokit.IOUserEthernet 1.0.1 com.apple.driver.AppleUpstreamUserClient 3.6.1 com.apple.Dont_Steal_Mac_OS_X 7.0.0 com.apple.driver.AppleHWAccess 1 com.apple.driver.AppleHV 1 com.apple.GeForceTesla 10.0.0 com.apple.driver.AppleSMCLMU 2.0.7d0 com.apple.iokit.CSRBluetoothHostControllerUSBTransport 4.3.2f6 com.apple.driver.AppleSMCPDRC 1.0.0 com.apple.driver.ACPI_SMC_PlatformPlugin 1.0.0 com.apple.driver.AppleBacklight 170.5.0 com.apple.driver.AppleMCCSControl 1.2.11 com.apple.driver.AppleLPC 1.7.3 com.apple.driver.SMCMotionSensor 3.0.4d1 com.apple.driver.AppleUSBTrackpad 240.2 com.apple.driver.AppleUSBTCKeyEventDriver 240.2 com.apple.driver.AppleUSBTCKeyboard 240.2 com.apple.driver.AppleIRController 327.5 com.apple.AppleFSCompression.AppleFSCompressionTypeDataless 1.0.0d1 com.apple.AppleFSCompression.AppleFSCompressionTypeZlib 1.0.0d1 com.apple.BootCache 35 com.apple.iokit.SCSITaskUserClient 3.7.3 com.apple.driver.XsanFilter 404 com.apple.iokit.IOAHCIBlockStorage 2.7.0 com.apple.driver.AppleFWOHCI 5.5.2 com.apple.driver.AppleAHCIPort 3.1.0 com.apple.driver.AppleIntelPIIXATA 2.5.1 com.apple.driver.AppleUSBHub 705.4.2 com.apple.driver.AirPort.Atheros40 700.74.5 com.apple.iokit.AppleYukon2 3.2.3b1 com.apple.driver.AppleUSBEHCI 705.4.14 com.apple.driver.AppleUSBUHCI 656.4.1 com.apple.driver.AppleSmartBatteryManager 161.0.0 com.apple.driver.AppleRTC 2.0 com.apple.driver.AppleHPET 1.8 com.apple.driver.AppleACPIButtons 3.1 com.apple.driver.AppleSMBIOS 2.1 com.apple.driver.AppleACPIEC 3.1 com.apple.driver.AppleAPIC 1.7 com.apple.driver.AppleIntelCPUPowerManagementClient 218.0.0 com.apple.nke.applicationfirewall 161 com.apple.security.quarantine 3 com.apple.security.TMSafetyNet 8 com.apple.driver.AppleIntelCPUPowerManagement 218.0.0 com.apple.security.SecureRemotePassword 1.0 com.apple.kext.triggers 1.0 com.apple.iokit.IOSerialFamily 11 com.apple.driver.DspFuncLib 269.25 com.apple.kext.OSvKernDSPLib 1.15 com.apple.iokit.IOSurface 97 com.apple.iokit.IOFireWireIP 2.2.6 com.apple.driver.AppleHDAController 269.25 com.apple.iokit.IOHDAFamily 269.25 com.apple.iokit.IOAudioFamily 203.3 com.apple.vecLib.kext 1.2.0 com.apple.nvidia.classic.NVDANV50HalTesla 10.0.0 com.apple.nvidia.classic.NVDAResmanTesla 10.0.0 com.apple.iokit.IOBluetoothHostControllerUSBTransport 4.3.2f6 com.apple.iokit.IOBluetoothFamily 4.3.2f6 com.apple.driver.IOPlatformPluginLegacy 1.0.0 com.apple.iokit.IOUSBUserClient 705.4.0 com.apple.driver.AppleBacklightExpert 1.1.0 com.apple.driver.AppleSMBusController 1.0.13d1 com.apple.driver.IOPlatformPluginFamily 5.8.1d38 com.apple.iokit.IONDRVSupport 2.4.1 com.apple.iokit.IOGraphicsFamily 2.4.1 com.apple.driver.AppleSMC 3.1.9 com.apple.iokit.IOUSBHIDDriver 705.4.0 com.apple.driver.AppleUSBMergeNub 705.4.0 com.apple.driver.AppleUSBComposite 705.4.9 com.apple.iokit.IOSCSIMultimediaCommandsDevice 3.7.3 com.apple.iokit.IOBDStorageFamily 1.7 com.apple.iokit.IODVDStorageFamily 1.7.1 com.apple.iokit.IOCDStorageFamily 1.7.1 com.apple.iokit.IOATAPIProtocolTransport 3.5.0 com.apple.iokit.IOSCSIArchitectureModelFamily 3.7.3 com.apple.iokit.IOFireWireFamily 4.5.6 com.apple.iokit.IOAHCIFamily 2.7.5 com.apple.iokit.IOATAFamily 2.5.3 com.apple.iokit.IO80211Family 710.55 com.apple.iokit.IONetworkingFamily 3.2 com.apple.iokit.IOUSBFamily 710.4.14 com.apple.driver.AppleEFINVRAM 2.0 com.apple.driver.AppleEFIRuntime 2.0 com.apple.iokit.IOHIDFamily 2.0.0 com.apple.iokit.IOSMBusFamily 1.1 com.apple.security.sandbox 300.0 com.apple.kext.AppleMatch 1.0.0d1 com.apple.driver.AppleKeyStore 2 com.apple.driver.AppleMobileFileIntegrity 1.0.5 com.apple.driver.AppleCredentialManager 1.0 com.apple.driver.DiskImages 396 com.apple.iokit.IOStorageFamily 2.0 com.apple.iokit.IOReportFamily 31 com.apple.driver.AppleFDEKeyStore 28.30 com.apple.driver.AppleACPIPlatform 3.1 com.apple.iokit.IOPCIFamily 2.9 com.apple.iokit.IOACPIFamily 1.4 com.apple.kec.Libm 1 com.apple.kec.pthread 1 com.apple.kec.corecrypto 1.0 Model: MacBookPro3,1, BootROM MBP31.0070.B07, 2 processors, Intel Core 2 Duo, 2.6 GHz, 6 GB, SMC 1.18f5 Graphics: NVIDIA GeForce 8600M GT, GeForce 8600M GT, PCIe, 256 MB Memory Module: BANK 0/DIMM0, 4 GB, DDR2 SDRAM, 667 MHz, 0x7F7FBA0000000000, - Memory Module: BANK 1/DIMM1, 2 GB, DDR2 SDRAM, 667 MHz, 0x7FBA000000000000, 0x202020202020202020202020202020202020 AirPort: spairport_wireless_card_type_airport_extreme (0x168C, 0x87), Atheros 5416: 4.0.74.0-P2P Bluetooth: Version 4.3.2f6 15235, 3 services, 18 devices, 1 incoming serial ports Network Service: Wi-Fi, AirPort, en1 PCI Card: pci168c,24, Other Network Controller, PCI Slot 5 Serial ATA Device: OWC Mercury Electra 6G SSD, 240.06 GB Parallel ATA Device: MAT**bleep**ADVD-R UJ-85J USB Device: Built-in iSight USB Device: Bluetooth USB Host Controller USB Device: Apple Internal Keyboard / Trackpad USB Device: IR Receiver Thunderbolt Bus: XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX Anonymous UUID: 6F14766E-A2BA-ED2A-7C99-8A8ABEEAAB13 Sun Apr 19 22:14:44 2015 *** Panic Report *** panic(cpu 0 caller 0xffffff800e94131b): "vnode_rele_ext: vp 0xffffff8024d6a000 usecount -ve : -1. v_tag = 16, v_type = 1, v_flag = 84800."@/SourceCache/xnu/xnu-2782.20.48/bsd/vfs/vfs_subr.c:1867 Backtrace (CPU 0), Frame : Return Address 0xffffff80de252f30 : 0xffffff800e72bda1 0xffffff80de252fb0 : 0xffffff800e94131b 0xffffff80de252ff0 : 0xffffff7f8ee1958f 0xffffff80de253010 : 0xffffff7f8ee18de2 0xffffff80de253360 : 0xffffff7f8ee1ae94 0xffffff80de2533a0 : 0xffffff800eba0256 0xffffff80de253400 : 0xffffff800eb48289 0xffffff80de253ab0 : 0xffffff800eb41e07 0xffffff80de253bd0 : 0xffffff800e96f7f6 0xffffff80de253c60 : 0xffffff800e95eeca 0xffffff80de253d70 : 0xffffff800e955778 0xffffff80de253f50 : 0xffffff800ec4ba86 0xffffff80de253fb0 : 0xffffff800e835376 Kernel Extensions in backtrace: com.sophos.kext.sav(9.2.50)[D9AF65D9-4A18-3B20-86BB-17DEBC7D5852]@0xffffff7f8ee18000->0xffffff7f8ee1cfff BSD process name corresponding to current thread: mds Mac OS version: 14D136 Kernel version: Darwin Kernel Version 14.3.0: Mon Mar 23 11:59:05 PDT 2015; root:xnu-2782.20.48~5/RELEASE_X86_64 Kernel UUID: 4B3A11F4-77AA-3D27-A22D-81A1BC5B504D Kernel slide: 0x000000000e400000 Kernel text base: 0xffffff800e600000 __HIB text base: 0xffffff800e500000 System model name: MacBookPro3,1 (Mac-F42388C8) System uptime in nanoseconds: 47702144525253 last loaded kext at 1199926530888: com.apple.filesystems.smbfs 3.0.1 (addr 0xffffff7f90dc5000, size 389120) last unloaded kext at 350133678740: com.apple.iokit.IOAHCIPassThrough 1.0.3 (addr 0xffffff7f90055000, size 36864) loaded kexts: com.sophos.kext.sav 9.2.50 com.sophos.nke.swi 9.2.50 com.apple.filesystems.smbfs 3.0.1 com.apple.filesystems.afpfs 11.0 com.apple.nke.asp-tcp 8.0.0 com.apple.driver.AudioAUUC 1.70 com.apple.driver.AppleHWSensor 1.9.5d0 com.apple.filesystems.autofs 3.0 com.apple.iokit.IOBluetoothSerialManager 4.3.4f4 com.apple.driver.AppleOSXWatchdog 1 com.apple.driver.AppleHDA 272.18 com.apple.driver.AppleSMCPDRC 1.0.0 com.apple.driver.AppleSMCLMU 2.0.7d0 com.apple.iokit.IOUserEthernet 1.0.1 com.apple.Dont_Steal_Mac_OS_X 7.0.0 com.apple.driver.AppleHWAccess 1 com.apple.driver.AppleHV 1 com.apple.driver.AppleIntelSlowAdaptiveClocking 4.0.0 com.apple.iokit.CSRBluetoothHostControllerUSBTransport 4.3.4f4 com.apple.driver.AppleBacklight 170.7.4 com.apple.GeForceTesla 10.0.0 com.apple.driver.ACPI_SMC_PlatformPlugin 1.0.0 com.apple.driver.AppleLPC 1.7.3 com.apple.driver.AppleUpstreamUserClient 3.6.1 com.apple.driver.AppleMCCSControl 1.2.11 com.apple.driver.SMCMotionSensor 3.0.4d1 com.apple.driver.AppleUSBTrackpad 240.2 com.apple.driver.AppleUSBTCKeyEventDriver 240.2 com.apple.driver.AppleUSBTCKeyboard 240.2 com.apple.driver.AppleIRController 327.5 com.apple.AppleFSCompression.AppleFSCompressionTypeDataless 1.0.0d1 com.apple.AppleFSCompression.AppleFSCompressionTypeZlib 1.0.0d1 com.apple.BootCache 36 com.apple.iokit.SCSITaskUserClient 3.7.5 com.apple.driver.XsanFilter 404 com.apple.iokit.IOAHCIBlockStorage 2.7.1 com.apple.driver.AppleUSBHub 705.4.2 com.apple.driver.AppleIntelPIIXATA 2.5.1 com.apple.driver.AppleFWOHCI 5.5.2 com.apple.driver.AppleAHCIPort 3.1.2 com.apple.driver.AppleUSBEHCI 705.4.14 com.apple.iokit.AppleYukon2 3.2.3b1 com.apple.driver.AirPort.Atheros40 700.74.5 com.apple.driver.AppleUSBUHCI 656.4.1 com.apple.driver.AppleSmartBatteryManager 161.0.0 com.apple.driver.AppleRTC 2.0 com.apple.driver.AppleHPET 1.8 com.apple.driver.AppleACPIButtons 3.1 com.apple.driver.AppleSMBIOS 2.1 com.apple.driver.AppleACPIEC 3.1 com.apple.driver.AppleAPIC 1.7 com.apple.driver.AppleIntelCPUPowerManagementClient 218.0.0 com.apple.nke.applicationfirewall 161 com.apple.security.quarantine 3 com.apple.security.TMSafetyNet 8 com.apple.driver.AppleIntelCPUPowerManagement 218.0.0 com.apple.security.SecureRemotePassword 1.0 com.apple.kext.triggers 1.0 com.apple.iokit.IOSerialFamily 11 com.apple.driver.DspFuncLib 272.18 com.apple.kext.OSvKernDSPLib 1.15 com.apple.iokit.IOFireWireIP 2.2.6 com.apple.iokit.IOSurface 97.4 com.apple.iokit.IOSlowAdaptiveClockingFamily 1.0.0 com.apple.driver.AppleHDAController 272.18 com.apple.iokit.IOHDAFamily 272.18 com.apple.iokit.IOAudioFamily 203.3 com.apple.vecLib.kext 1.2.0 com.apple.iokit.IOUSBUserClient 705.4.0 com.apple.iokit.IOBluetoothHostControllerUSBTransport 4.3.4f4 com.apple.iokit.IOBluetoothFamily 4.3.4f4 com.apple.driver.AppleBacklightExpert 1.1.0 com.apple.nvidia.classic.NVDANV50HalTesla 10.0.0 com.apple.driver.IOPlatformPluginLegacy 1.0.0 com.apple.driver.IOPlatformPluginFamily 5.9.1d7 com.apple.driver.AppleSMBusController 1.0.13d1 com.apple.nvidia.classic.NVDAResmanTesla 10.0.0 com.apple.iokit.IONDRVSupport 2.4.1 com.apple.iokit.IOGraphicsFamily 2.4.1 com.apple.driver.AppleSMC 3.1.9 com.apple.iokit.IOUSBHIDDriver 705.4.0 com.apple.driver.AppleUSBMergeNub 705.4.0 com.apple.driver.AppleUSBComposite 705.4.9 com.apple.iokit.IOSCSIMultimediaCommandsDevice 3.7.5 com.apple.iokit.IOBDStorageFamily 1.7 com.apple.iokit.IODVDStorageFamily 1.7.1 com.apple.iokit.IOCDStorageFamily 1.7.1 com.apple.iokit.IOATAPIProtocolTransport 3.5.0 com.apple.iokit.IOSCSIArchitectureModelFamily 3.7.5 com.apple.iokit.IOATAFamily 2.5.3 com.apple.iokit.IOFireWireFamily 4.5.6 com.apple.iokit.IOAHCIFamily 2.7.5 com.apple.iokit.IO80211Family 730.60 com.apple.iokit.IONetworkingFamily 3.2 com.apple.iokit.IOUSBFamily 720.4.4 com.apple.driver.AppleEFINVRAM 2.0 com.apple.driver.AppleEFIRuntime 2.0 com.apple.iokit.IOHIDFamily 2.0.0 com.apple.iokit.IOSMBusFamily 1.1 com.apple.security.sandbox 300.0 com.apple.kext.AppleMatch 1.0.0d1 com.apple.driver.AppleKeyStore 2 com.apple.driver.AppleMobileFileIntegrity 1.0.5 com.apple.driver.AppleCredentialManager 1.0 com.apple.driver.DiskImages 396 com.apple.iokit.IOStorageFamily 2.0 com.apple.iokit.IOReportFamily 31 com.apple.driver.AppleFDEKeyStore 28.30 com.apple.driver.AppleACPIPlatform 3.1 com.apple.iokit.IOPCIFamily 2.9 com.apple.iokit.IOACPIFamily 1.4 com.apple.kec.Libm 1 com.apple.kec.pthread 1 com.apple.kec.corecrypto 1.0 Model: MacBookPro3,1, BootROM MBP31.0070.B07, 2 processors, Intel Core 2 Duo, 2.6 GHz, 6 GB, SMC 1.18f5 Graphics: NVIDIA GeForce 8600M GT, GeForce 8600M GT, PCIe, 256 MB Memory Module: BANK 0/DIMM0, 4 GB, DDR2 SDRAM, 667 MHz, 0x7F7FBA0000000000, - Memory Module: BANK 1/DIMM1, 2 GB, DDR2 SDRAM, 667 MHz, 0x7FBA000000000000, 0x202020202020202020202020202020202020 AirPort: spairport_wireless_card_type_airport_extreme (0x168C, 0x87), Atheros 5416: 4.0.74.0-P2P Bluetooth: Version 4.3.4f4 15601, 3 services, 18 devices, 1 incoming serial ports Network Service: Wi-Fi, AirPort, en1 PCI Card: pci168c,24, Other Network Controller, PCI Slot 5 Serial ATA Device: OWC Mercury Electra 6G SSD, 240.06 GB Parallel ATA Device: MAT**bleep**ADVD-R UJ-85J USB Device: Built-in iSight USB Device: Bluetooth USB Host Controller USB Device: Apple Internal Keyboard / Trackpad USB Device: IR Receiver Thunderbolt Bus:

I am not sure why my post is not displaying properly, but the information is fine.

It's a good idea to post long log extracts using the 'Insert Code' option on the toolbar in the posting editor.

Users do post that SAV is the cause and from my experience the thing that makes them decide it's SAV is because SAV is nearly always mentioned in the report.  That's because SAV is always running to protect the computer and then errors during a crash - whether it caused it or not.

I'm not saying SAV isn't causing it.  However if it was purely SAV more/all users would be reporting it.  To investigate this further you need to consider (a) is it SAV or not, and (b) if it's SAV what else is running or what am I or the computer doing just before the crash?

To test it may be worth disabling the on-access scanner for a few days to see if a crash still occurs.  If it does try installing SAV and repeating.  If it doesn't switch the on-access scanner back on and see if the error comes back.  Obviously be careful browsing and clicking on things you don't trust while testing.

Other steps can be to reboot the computer, disabling any programs that start automatically during boot/logon that you don't require, creating a second user account and use that for a few days to see if it's only affecting your profile, and of course: running disk utility to check the check of the hard drive.

The important thing is to be sure it is SAV on it's own, or in combination with another program you have running that is causing the crash.  Once we know that we can take the next step.

same here

mac osx 10.10.3 (14D136)

sophos 9.2.4

panic(cpu 4 caller 0xffffff801014131b): "vnode_rele_ext: vp 0xffffff8044627780 usecount -ve : -1.  v_tag = 16, v_type = 1, v_flag = 84800."@/SourceCache/xnu/xnu-2782.20.48/bsd/vfs/vfs_subr.c:1867

Backtrace (CPU 4), Frame : Return Address

0xffffff81fd3eaf30 : 0xffffff800ff2bda1

0xffffff81fd3eafb0 : 0xffffff801014131b

0xffffff81fd3eaff0 : 0xffffff7f9068a58f

0xffffff81fd3eb010 : 0xffffff7f90689de2

0xffffff81fd3eb360 : 0xffffff7f9068be94

0xffffff81fd3eb3a0 : 0xffffff80103a0256

0xffffff81fd3eb400 : 0xffffff8010348289

0xffffff81fd3ebab0 : 0xffffff8010341e07

0xffffff81fd3ebbd0 : 0xffffff801016f7f6

0xffffff81fd3ebc60 : 0xffffff801015eeca

0xffffff81fd3ebd70 : 0xffffff8010155778

0xffffff81fd3ebf50 : 0xffffff801044ba86

0xffffff81fd3ebfb0 : 0xffffff8010035376

      Kernel Extensions in backtrace:

         com.sophos.kext.sav(9.2.50)[D9AF65D9-4A18-3B20-86BB-17DEBC7D5852]@0xffffff7f90689000->0xffffff7f9068dfff

Hi Weiteng,

Earlier in the thread Ruckus gave a good list of things you can try if you experience this. We need to make sure the panic is actually being caused by SAV running, and not some other combination of events:

To test it may be worth disabling the on-access scanner for a few days to see if a crash still occurs. If it does try installing SAV and repeating. If it doesn't switch the on-access scanner back on and see if the error comes back. Obviously be careful browsing and clicking on things you don't trust while testing.

Other steps can be to reboot the computer, disabling any programs that start automatically during boot/logon that you don't require, creating a second user account and use that for a few days to see if it's only affecting your profile, and of course: running disk utility to check the check of the hard drive.

Can you please give that a try, and let us know if you're still having trouble?

This problem has happened repeatedly on various kinds of Apple computers running Yosemite in my organization.  It happened 5 times in three weeks on an iMac that has never had any kernel panics in 2 years.  In fact, on some of these computers the DiagnosticReports under /Library/Logs contains tons of exceptions:

Exception Type: EXC_BREAKPOINT (SIGTRAP)
Exception Codes: 0x0000000000000002, 0x0000000000000000

Application Specific Information:
*** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '*** -[NSFileManager fileSystemRepresentationWithPath:]: nil or empty path argument'

Removing SAV from the iMac eliminated the instability.

A machine has started showing these signs within two weeks of a bare metal installation of Yosemite.  While all this evidence is highly circumstancial,  it does point to some weird interaction with SAV 9.2.50.  

I would not recommend the above action as a broad remedy but seek feedback on possible solutions.