The machine-dependent code must support this interface for operation with
ipkdb(4).
During system bootstrap, machine-dependent code must invoke
ipkdb_init(). If the kernel is booted with
RB_KDB set in
boothowto (see
boothowto(9)),
ipkdb(4) is enabled by invoking
ipkdb_connect(), setting the
when argument to 0.
ipkdbcmds() is invoked by machine-dependent code when the trap mechanism determines that the debugger should be entered, i.e., on a single step or breakpoint interrupt from kernel code. The trapping mechanism should already have stored the registers into the global area ipkdbregs. The layout of this area must be the same as that expected by
gdb(1). Valid return values are:
IPKDB_CMD_RUN
user wants to continue
IPKDB_CMD_STEP
user wants to do single stepping
IPKDB_CMD_EXIT
user has detached from debugging