Panic on boot, need to use single user mode (was: need to rebuild kext cache)

I encountered the same problem after updating to 10.10.1.

When I was booting through single user mode I noticed that fsck was reporting that the root file system didn't have journaling enabled.

After booting into OS X Recovery and enabling journaling on the volume in Disk Utility the kernel panics stopped.

I suspect that your problem will be solved by this as well as my panic seems to have the same callstack:

0xffffff875d5f3b40 : 0xffffff801573a811 mach_kernel : _panic + 0xd1
0xffffff875d5f3bc0 : 0xffffff801581e80a mach_kernel : _kernel_trap + 0x84a
0xffffff875d5f3d80 : 0xffffff801583a443 mach_kernel : _return_from_trap + 0xe3
0xffffff875d5f3da0 : 0xffffff801550e11b 
0xffffff875d5f3ed0 : 0xffffff8015b7d684 mach_kernel : _NodesAreContiguous + 0x1794
0xffffff875d5f3f80 : 0x0