2011 MacBook Pro constantly crashing

So my issue seems to be a recurring kernel panic, based on the messages that are displayed upon startup. Here is some of the kernel panic report:

Interval Since Last Panic Report: 135347 sec

Panics Since Last Report: 10

Anonymous UUID: D0CCB605-2E33-D9E1-F013-B1C1AB1D6829

Wed Feb 13 01:45:09 2013

panic(cpu 2 caller 0xffffff802f4b7bd5): Kernel trap at 0xffffff802f4874b3, type 14=page fault, registers:

CR0: 0x000000008001003b, CR2: 0xffffff801a879308, CR3: 0x0000000031e6f000, CR4: 0x00000000000606e0

RAX: 0xffffff801a879308, RBX: 0xffffff803963a0a8, RCX: 0xffffff801a879308, RDX: 0x0000000000000004

RSP: 0xffffff811fbe3dc0, RBP: 0xffffff811fbe3de0, RSI: 0x0000000023c34600, RDI: 0xffffff80333f48c0

R8: 0x0000000000000001, R9: 0x0000000000000000, R10: 0xffffff802fabdc22, R11: 0x00000000ffffff01

R12: 0x000000000000918a, R13: 0x000000000000006e, R14: 0xffffff80333f48c0, R15: 0xffffff80323f0000

RFL: 0x0000000000010282, RIP: 0xffffff802f4874b3, CS: 0x0000000000000008, SS: 0x0000000000000010

Fault CR2: 0xffffff801a879308, Error code: 0x0000000000000000, Fault CPU: 0x2

Backtrace (CPU 2), Frame : Return Address

0xffffff811fbe3a60 : 0xffffff802f41d626

0xffffff811fbe3ad0 : 0xffffff802f4b7bd5

0xffffff811fbe3ca0 : 0xffffff802f4ce4ed

0xffffff811fbe3cc0 : 0xffffff802f4874b3

0xffffff811fbe3de0 : 0xffffff802f47e01f

0xffffff811fbe3f70 : 0xffffff802f47ecf2

0xffffff811fbe3fb0 : 0xffffff802f4b26b7

BSD process name corresponding to current thread: kernel_task

Mac OS version:

12C60

Kernel version:

Darwin Kernel Version 12.2.0: Sat Aug 25 00:48:52 PDT 2012; root:xnu-2050.18.24~1/RELEASE_X86_64

Kernel UUID: 69A5853F-375A-3EF4-9247-478FD0247333

Kernel slide: 0x000000002f200000

Kernel text base: 0xffffff802f400000

System model name: MacBookPro8,2 (Mac-94245A3940C91C80)

Oaky I think I might have misdiagnosed my problem. I do not receive a message that says "You need to shutdown your computer". What happens in my case is, the computer just reboots instantaneously without warning. Not sure if this indicates a kernel panic.

Do you by any chance have CrashPlan? I do, and it seems like the majority of the time when a KP happens, it happens while the CP backup engine is running AND I happen to have a USB device (such as an external hard drive) plugged in. I called AppleCare to see what they had to offer in the way of advice, and they had me through the usual troubleshooting motions: update OS if there are any available (there wasn't), verify and repair the disk permissions through recovery (there were no errors), try booting in safe mode, and resetting PRAM, all of which didn't work. He then basically told me to back up my hard drive and format and reinstall from scratch, and manually migrate only my documents, media, and apps; no system files such as the user library folder or any other system/preference folders. Overkill probably, but I have done this many times so it wasn't a big deal for me. He explained that the problem is likely due to external 3rd devices, such as USB hard drives, and that I should investigate and try to update the drivers for these. Meanwhile, I have formatted and reinstalled, but did not install the user library directory, CrashPlan, nor java (which CrashPlan depends on). So far I have not any KP's, including when USB devices are attached.