Kernel debugger

A kernel debugger is a debugger present in some operating system kernels to ease debugging and kernel development by the kernel developers. A kernel debugger might be a stub implementing low-level operations, with a full-blown debugger such as GNU Debugger (gdb), running on another machine, sending commands to the stub over a serial line or a network connection, or it might provide a command line that can be used directly on the machine being debugged.
Operating systems and operating system kernels that contain a kernel debugger: