| 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. |