===============
Provoke crashes
===============

The lkdtm module provides an interface to crash or injure the kernel at
predefined crashpoints to evaluate the reliability of crash dumps obtained
using different dumping solutions. The module uses KPROBEs to instrument
crashing points, but can also crash the kernel directly without KRPOBE
support.


You can provide the way either through module arguments when inserting
the module, or through a debugfs interface.

Usage::

	insmod lkdtm.ko [recur_count={>0}] cpoint_name=<> cpoint_type=<>
			[cpoint_count={>0}]

recur_count
	Recursion level for the stack overflow test. Default is 10.

cpoint_name
	Crash point where the kernel is to be crashed. It can be
	one of INT_HARDWARE_ENTRY, INT_HW_IRQ_EN, INT_TASKLET_ENTRY,
	FS_DEVRW, MEM_SWAPOUT, TIMERADD, SCSI_DISPATCH_CMD,
	IDE_CORE_CP, DIRECT

cpoint_type
	Indicates the action to be taken on hitting the crash point.
	It can be one of PANIC, BUG, EXCEPTION, LOOP, OVERFLOW,
	CORRUPT_STACK, UNALIGNED_LOAD_STORE_WRITE, OVERWRITE_ALLOCATION,
	WRITE_AFTER_FREE,

cpoint_count
	Indicates the number of times the crash point is to be hit
	to trigger an action. The default is 10.

You can also induce failures by mounting debugfs and writing the type to
<mountpoint>/provoke-crash/<crashpoint>. E.g.::

  mount -t debugfs debugfs /mnt
  echo EXCEPTION > /mnt/provoke-crash/INT_HARDWARE_ENTRY


A special file is `DIRECT` which will induce the crash directly without
KPROBE instrumentation. This mode is the only one available when the module
is built on a kernel without KPROBEs support.