What is the cause of my kernel panic?

Question

I'm experiencing a repeated kernel panic and I don't know what the problem is. I've troubleshooted nearly all third party kernels, repaired disk permissions multiple times, all my memory is fine. What is the problem?
Here is a kernel panic log.
Sun Nov 24 15:47:44 2013
panic(cpu 3 caller 0x226ec0): "thread_invoke: preemption_level -1, possible cause: unlocking an unlocked mutex or spinlock"@/SourceCache/xnu/xnu-1504.15.3/osfmk/kern/sched_prim.c:1471
Backtrace (CPU 3), Frame : Return Address (4 potential args on stack)
0x88683e18 : 0x21b837 (0x5dd7fc 0x88683e4c 0x223ce1 0x0)
0x88683e68 : 0x226ec0 (0x593ab8 0xffffffff 0x593a50 0x226a81)
0x88683ee8 : 0x2275c6 (0x10e2e7c4 0x0 0xffffffff 0x0)
0x88683f58 : 0x227631 (0x23014c 0x863ea0 0x0 0x2a45c9)
0x88683f78 : 0x2302e6 (0x23014c 0x863ea0 0x0 0x0)
0x88683fc8 : 0x2a179c (0x863ea0 0x0 0x10 0x1a9da724)
BSD process name corresponding to current thread: kernel_task
Mac OS version:
10K549
Kernel version:
Darwin Kernel Version 10.8.0: Tue Jun  7 16:33:36 PDT 2011; root:xnu-1504.15.3~1/RELEASE_I386
System model name: MacPro2,1 (Mac-F4208DA9)
System uptime in nanoseconds: 20427443102547
unloaded kexts:
com.apple.driver.AppleFileSystemDriver          2.0 (addr 0xe9a000, size 0x12288) - last unloaded 80506837428
loaded kexts:
com.Cycling74.driver.Soundflower          1.6.6
com.razer.common.razerhid          7.47
com.apple.driver.AppleHWSensor          1.9.3d0 - last loaded 11339262195
com.apple.filesystems.autofs          2.1.0
com.apple.driver.AppleUpstreamUserClient          3.5.7
com.apple.driver.AppleMCCSControl          1.0.20
com.apple.driver.AppleHDA          2.0.5f14
com.apple.driver.AudioAUUC          1.57
com.apple.GeForce          6.3.7
com.apple.Dont_Steal_Mac_OS_X          7.0.0
com.apple.iokit.CHUDUtils          364
com.apple.iokit.CHUDProf          366
com.apple.driver.AudioIPCDriver          1.1.6
com.apple.driver.AppleMCEDriver          1.1.9
com.apple.driver.AppleIntelMeromProfile          19.1
com.apple.driver.ACPI_SMC_PlatformPlugin          4.7.0a1
com.apple.driver.AppleLPC          1.5.1
com.apple.filesystems.ntfs          3.4
com.apple.iokit.SCSITaskUserClient          2.6.8
com.apple.BootCache          31.1
com.apple.AppleFSCompression.AppleFSCompressionTypeZlib          1.0.0d1
com.apple.driver.AppleIntel8254XEthernet          2.1.3b1
com.apple.iokit.IOAHCIBlockStorage          1.6.4
com.apple.driver.AppleUSBHub          4.2.4
com.apple.driver.AppleFWOHCI          4.7.3
com.apple.driver.AppleAHCIPort          2.1.7
com.apple.driver.AppleIntelPIIXATA          2.5.1
com.apple.driver.AppleEFINVRAM          1.4.0
com.apple.driver.AppleUSBEHCI          4.2.4
com.apple.driver.AppleUSBUHCI          4.2.0
com.apple.driver.AppleACPIButtons          1.3.6
com.apple.driver.AppleRTC          1.3.1
com.apple.driver.AppleHPET          1.5
com.apple.driver.AppleSMBIOS          1.7
com.apple.driver.AppleACPIEC          1.3.6
com.apple.driver.AppleAPIC          1.4
com.apple.driver.AppleIntelCPUPowerManagementClient          142.6.0
com.apple.security.sandbox          1
com.apple.security.quarantine          0
com.apple.nke.applicationfirewall          2.1.14
com.apple.driver.AppleIntelCPUPowerManagement          142.6.0
com.apple.driver.AppleProfileReadCounterAction          17
com.apple.driver.DspFuncLib          2.0.5f14
com.apple.driver.AppleProfileTimestampAction          10
com.apple.driver.AppleProfileThreadInfoAction          14
com.apple.driver.AppleProfileRegisterStateAction          10
com.apple.driver.AppleProfileKEventAction          10
com.apple.driver.AppleProfileCallstackAction          20
com.apple.nvidia.nv50hal          6.3.7
com.apple.NVDAResman          6.3.7
com.apple.iokit.IONDRVSupport          2.2.1
com.apple.iokit.IOFireWireIP          2.0.3
com.apple.driver.AppleUSBAudio          2.7.6f6
com.apple.iokit.IOSurface          74.2
com.apple.iokit.IOBluetoothSerialManager          2.4.5f3
com.apple.iokit.IOSerialFamily          10.0.3
com.apple.iokit.CHUDKernLib          365
com.apple.iokit.IOAudioFamily          1.8.3fc2
com.apple.kext.OSvKernDSPLib          1.3
com.apple.driver.AppleHDAController          2.0.5f14
com.apple.iokit.IOGraphicsFamily          2.2.1
com.apple.iokit.IOHDAFamily          2.0.5f14
com.apple.iokit.AppleProfileFamily          41.4
com.apple.driver.AppleSMC          3.1.0d5
com.apple.driver.IOPlatformPluginFamily          4.7.0a1
com.apple.driver.IOBluetoothHIDDriver          2.4.5f3
com.apple.iokit.IOBluetoothFamily          2.4.5f3
com.apple.iokit.IOUSBHIDDriver          4.2.0
com.apple.driver.AppleUSBComposite          3.9.0
com.apple.iokit.IOSCSIMultimediaCommandsDevice          2.6.8
com.apple.iokit.IOBDStorageFamily          1.6
com.apple.iokit.IODVDStorageFamily          1.6
com.apple.iokit.IOCDStorageFamily          1.6.1
com.apple.driver.XsanFilter          402.1
com.apple.iokit.IOATAPIProtocolTransport          2.5.1
com.apple.iokit.IOSCSIArchitectureModelFamily          2.6.8
com.apple.iokit.IONetworkingFamily          1.10
com.apple.iokit.IOFireWireFamily          4.2.6
com.apple.iokit.IOUSBUserClient          4.2.4
com.apple.iokit.IOAHCIFamily          2.0.6
com.apple.iokit.IOATAFamily          2.5.1
com.apple.iokit.IOUSBFamily          4.2.4
com.apple.driver.AppleEFIRuntime          1.4.0
com.apple.iokit.IOHIDFamily          1.6.6
com.apple.iokit.IOSMBusFamily          1.1
com.apple.kext.AppleMatch          1.0.0d1
com.apple.security.TMSafetyNet          6
com.apple.driver.DiskImages          289.1
com.apple.iokit.IOStorageFamily          1.6.3
com.apple.driver.AppleACPIPlatform          1.3.6
com.apple.iokit.IOPCIFamily          2.6.5
com.apple.iokit.IOACPIFamily          1.3.0

Answer 1

If no KP while in safe mode, then I suspect one of these:
com.Cycling74.driver.Soundflower          1.6.6
com.razer.common.razerhid          7.47
Uninstall and reinstall, one at a time, and reboot. If KP, delete the culprit.
If KP, in safe mode, then most likely hardware related. Run the Apple Hardware Test suite, extended tests at least twice, followed by Rember.  See
OS X About kernel panics,
Technical Note TN2063: Understanding and Debugging Kernel Panics,
Mac OS X Kernel Panic FAQ,
Resolving Kernel Panics,
How to troubleshoot a kernel panic, and
Tutorial: Avoiding and eliminating Kernel panics for more details.