KGDB: kernel debugging with remote gdb

modulename: debug_core.ko

and/or

kgdb.ko

and/or

xtensa-stub.ko

configname: CONFIG_KGDB

Linux Kernel Configuration
└─>KGDB: kernel debugging with remote gdb
In linux kernel since version 2.6.12  
If you say Y here, it will be possible to remotely debug the
kernel using gdb. It is recommended but not required, that
you also turn on the kernel config option
CONFIG_FRAME_POINTER to aid in producing more reliable stack
backtraces in the external debugger. Documentation of
kernel debugger is available at http://kgdb.sourceforge.net
as well as in DocBook form in Documentation/DocBook/. If
unsure, say N.

source code:
depends
CONFIG_DEBUG_KERNEL
CONFIG_EXPERIMENTAL
CONFIG_HAVE_ARCH_KGDB