[linux.git] / drivers / misc / lkdtm.c

/*
 * Kprobe module for testing crash dumps
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 *
 * Copyright (C) IBM Corporation, 2006
 *
 * Author: Ankita Garg <[email protected]>
 *
 * This module induces system failures at predefined crashpoints to
 * evaluate the reliability of crash dumps obtained using different dumping
 * solutions.
 *
 * It is adapted from the Linux Kernel Dump Test Tool by
 * Fernando Luis Vazquez Cao <http://lkdtt.sourceforge.net>
 *
 * 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
 *
 * cpoint_type : Indicates the action to be taken on hitting the crash point.
 *		 It can be one of PANIC, BUG, EXCEPTION, LOOP, OVERFLOW
 *
 * cpoint_count : Indicates the number of times the crash point is to be hit
 *		  to trigger an action. The default is 10.
 */

#include <linux/kernel.h>
#include <linux/fs.h>
#include <linux/module.h>
#include <linux/buffer_head.h>
#include <linux/kprobes.h>
#include <linux/list.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/hrtimer.h>
#include <scsi/scsi_cmnd.h>

#ifdef CONFIG_IDE
#include <linux/ide.h>
#endif

#define NUM_CPOINTS 8
#define NUM_CPOINT_TYPES 5
#define DEFAULT_COUNT 10
#define REC_NUM_DEFAULT 10

enum cname {
	INVALID,
	INT_HARDWARE_ENTRY,
	INT_HW_IRQ_EN,
	INT_TASKLET_ENTRY,
	FS_DEVRW,
	MEM_SWAPOUT,
	TIMERADD,
	SCSI_DISPATCH_CMD,
	IDE_CORE_CP
};

enum ctype {
	NONE,
	PANIC,
	BUG,
	EXCEPTION,
	LOOP,
	OVERFLOW
};

static char* cp_name[] = {
	"INT_HARDWARE_ENTRY",
	"INT_HW_IRQ_EN",
	"INT_TASKLET_ENTRY",
	"FS_DEVRW",
	"MEM_SWAPOUT",
	"TIMERADD",
	"SCSI_DISPATCH_CMD",
	"IDE_CORE_CP"
};

static char* cp_type[] = {
	"PANIC",
	"BUG",
	"EXCEPTION",
	"LOOP",
	"OVERFLOW"
};

static struct jprobe lkdtm;

static int lkdtm_parse_commandline(void);
static void lkdtm_handler(void);

static char* cpoint_name;
static char* cpoint_type;
static int cpoint_count = DEFAULT_COUNT;
static int recur_count = REC_NUM_DEFAULT;

static enum cname cpoint = INVALID;
static enum ctype cptype = NONE;
static int count = DEFAULT_COUNT;

module_param(recur_count, int, 0644);
MODULE_PARM_DESC(recur_count, " Recursion level for the stack overflow test, "\
				 "default is 10");
module_param(cpoint_name, charp, 0644);
MODULE_PARM_DESC(cpoint_name, " Crash Point, where kernel is to be crashed");
module_param(cpoint_type, charp, 0644);
MODULE_PARM_DESC(cpoint_type, " Crash Point Type, action to be taken on "\
				"hitting the crash point");
module_param(cpoint_count, int, 0644);
MODULE_PARM_DESC(cpoint_count, " Crash Point Count, number of times the "\
				"crash point is to be hit to trigger action");

static unsigned int jp_do_irq(unsigned int irq)
{
	lkdtm_handler();
	jprobe_return();
	return 0;
}

static irqreturn_t jp_handle_irq_event(unsigned int irq,
				       struct irqaction *action)
{
	lkdtm_handler();
	jprobe_return();
	return 0;
}

static void jp_tasklet_action(struct softirq_action *a)
{
	lkdtm_handler();
	jprobe_return();
}

static void jp_ll_rw_block(int rw, int nr, struct buffer_head *bhs[])
{
	lkdtm_handler();
	jprobe_return();
}

struct scan_control;

static unsigned long jp_shrink_inactive_list(unsigned long max_scan,
					     struct zone *zone,
					     struct scan_control *sc)
{
	lkdtm_handler();
	jprobe_return();
	return 0;
}

static int jp_hrtimer_start(struct hrtimer *timer, ktime_t tim,
			    const enum hrtimer_mode mode)
{
	lkdtm_handler();
	jprobe_return();
	return 0;
}

static int jp_scsi_dispatch_cmd(struct scsi_cmnd *cmd)
{
	lkdtm_handler();
	jprobe_return();
	return 0;
}

#ifdef CONFIG_IDE
int jp_generic_ide_ioctl(ide_drive_t *drive, struct file *file,
			struct block_device *bdev, unsigned int cmd,
			unsigned long arg)
{
	lkdtm_handler();
	jprobe_return();
	return 0;
}
#endif

static int lkdtm_parse_commandline(void)
{
	int i;

	if (cpoint_name == NULL || cpoint_type == NULL ||
					cpoint_count < 1 || recur_count < 1)
		return -EINVAL;

	for (i = 0; i < NUM_CPOINTS; ++i) {
		if (!strcmp(cpoint_name, cp_name[i])) {
			cpoint = i + 1;
			break;
		}
	}

	for (i = 0; i < NUM_CPOINT_TYPES; ++i) {
		if (!strcmp(cpoint_type, cp_type[i])) {
			cptype = i + 1;
			break;
		}
	}

	if (cpoint == INVALID || cptype == NONE)
                return -EINVAL;

	count = cpoint_count;

	return 0;
}

static int recursive_loop(int a)
{
	char buf[1024];

	memset(buf,0xFF,1024);
	recur_count--;
	if (!recur_count)
		return 0;
	else
        	return recursive_loop(a);
}

void lkdtm_handler(void)
{
	printk(KERN_INFO "lkdtm : Crash point %s of type %s hit\n",
					 cpoint_name, cpoint_type);
	--count;

	if (count == 0) {
		switch (cptype) {
		case NONE:
			break;
		case PANIC:
			printk(KERN_INFO "lkdtm : PANIC\n");
			panic("dumptest");
			break;
		case BUG:
			printk(KERN_INFO "lkdtm : BUG\n");
			BUG();
			break;
		case EXCEPTION:
			printk(KERN_INFO "lkdtm : EXCEPTION\n");
			*((int *) 0) = 0;
			break;
		case LOOP:
			printk(KERN_INFO "lkdtm : LOOP\n");
			for (;;);
			break;
		case OVERFLOW:
			printk(KERN_INFO "lkdtm : OVERFLOW\n");
			(void) recursive_loop(0);
			break;
		default:
			break;
		}
		count = cpoint_count;
	}
}

static int __init lkdtm_module_init(void)
{
	int ret;

	if (lkdtm_parse_commandline() == -EINVAL) {
		printk(KERN_INFO "lkdtm : Invalid command\n");
		return -EINVAL;
	}

	switch (cpoint) {
	case INT_HARDWARE_ENTRY:
		lkdtm.kp.symbol_name = "do_IRQ";
		lkdtm.entry = (kprobe_opcode_t*) jp_do_irq;
		break;
	case INT_HW_IRQ_EN:
		lkdtm.kp.symbol_name = "handle_IRQ_event";
		lkdtm.entry = (kprobe_opcode_t*) jp_handle_irq_event;
		break;
	case INT_TASKLET_ENTRY:
		lkdtm.kp.symbol_name = "tasklet_action";
		lkdtm.entry = (kprobe_opcode_t*) jp_tasklet_action;
		break;
	case FS_DEVRW:
		lkdtm.kp.symbol_name = "ll_rw_block";
		lkdtm.entry = (kprobe_opcode_t*) jp_ll_rw_block;
		break;
	case MEM_SWAPOUT:
		lkdtm.kp.symbol_name = "shrink_inactive_list";
		lkdtm.entry = (kprobe_opcode_t*) jp_shrink_inactive_list;
		break;
	case TIMERADD:
		lkdtm.kp.symbol_name = "hrtimer_start";
		lkdtm.entry = (kprobe_opcode_t*) jp_hrtimer_start;
		break;
	case SCSI_DISPATCH_CMD:
		lkdtm.kp.symbol_name = "scsi_dispatch_cmd";
		lkdtm.entry = (kprobe_opcode_t*) jp_scsi_dispatch_cmd;
		break;
	case IDE_CORE_CP:
#ifdef CONFIG_IDE
		lkdtm.kp.symbol_name = "generic_ide_ioctl";
		lkdtm.entry = (kprobe_opcode_t*) jp_generic_ide_ioctl;
#else
		printk(KERN_INFO "lkdtm : Crash point not available\n");
#endif
		break;
	default:
		printk(KERN_INFO "lkdtm : Invalid Crash Point\n");
		break;
	}

	if ((ret = register_jprobe(&lkdtm)) < 0) {
                printk(KERN_INFO "lkdtm : Couldn't register jprobe\n");
                return ret;
	}

	printk(KERN_INFO "lkdtm : Crash point %s of type %s registered\n",
						cpoint_name, cpoint_type);
	return 0;
}

static void __exit lkdtm_module_exit(void)
{
        unregister_jprobe(&lkdtm);
        printk(KERN_INFO "lkdtm : Crash point unregistered\n");
}

module_init(lkdtm_module_init);
module_exit(lkdtm_module_exit);

MODULE_LICENSE("GPL");
Commit	Line	Data
8bb31b9d AG	1	/*
	2	* Kprobe module for testing crash dumps
	3	*
	4	* This program is free software; you can redistribute it and/or modify
	5	* it under the terms of the GNU General Public License as published by
	6	* the Free Software Foundation; either version 2 of the License, or
	7	* (at your option) any later version.
	8	*
	9	* This program is distributed in the hope that it will be useful,
	10	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	11	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	12	* GNU General Public License for more details.
	13	*
	14	* You should have received a copy of the GNU General Public License
	15	* along with this program; if not, write to the Free Software
	16	* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
	17	*
	18	* Copyright (C) IBM Corporation, 2006
	19	*
	20	* Author: Ankita Garg <[email protected]>
	21	*
	22	* This module induces system failures at predefined crashpoints to
	23	* evaluate the reliability of crash dumps obtained using different dumping
	24	* solutions.
	25	*
	26	* It is adapted from the Linux Kernel Dump Test Tool by
	27	* Fernando Luis Vazquez Cao <http://lkdtt.sourceforge.net>
	28	*
	29	* Usage : insmod lkdtm.ko [recur_count={>0}] cpoint_name=<> cpoint_type=<>
	30	* [cpoint_count={>0}]
	31	*
	32	* recur_count : Recursion level for the stack overflow test. Default is 10.
	33	*
	34	* cpoint_name : Crash point where the kernel is to be crashed. It can be
	35	* one of INT_HARDWARE_ENTRY, INT_HW_IRQ_EN, INT_TASKLET_ENTRY,
	36	* FS_DEVRW, MEM_SWAPOUT, TIMERADD, SCSI_DISPATCH_CMD,
	37	* IDE_CORE_CP
	38	*
	39	* cpoint_type : Indicates the action to be taken on hitting the crash point.
	40	* It can be one of PANIC, BUG, EXCEPTION, LOOP, OVERFLOW
	41	*
	42	* cpoint_count : Indicates the number of times the crash point is to be hit
	43	* to trigger an action. The default is 10.
	44	*/
	45
	46	#include <linux/kernel.h>
5d861d92	47	#include <linux/fs.h>
8bb31b9d	48	#include <linux/module.h>
5d861d92	49	#include <linux/buffer_head.h>
8bb31b9d	50	#include <linux/kprobes.h>
5d861d92	51	#include <linux/list.h>
8bb31b9d	52	#include <linux/init.h>
8bb31b9d	53	#include <linux/interrupt.h>
5d861d92	54	#include <linux/hrtimer.h>
8bb31b9d AG	55	#include <scsi/scsi_cmnd.h>
	56
	57	#ifdef CONFIG_IDE
	58	#include <linux/ide.h>
	59	#endif
	60
	61	#define NUM_CPOINTS 8
	62	#define NUM_CPOINT_TYPES 5
	63	#define DEFAULT_COUNT 10
	64	#define REC_NUM_DEFAULT 10
	65
	66	enum cname {
	67	INVALID,
	68	INT_HARDWARE_ENTRY,
	69	INT_HW_IRQ_EN,
	70	INT_TASKLET_ENTRY,
	71	FS_DEVRW,
	72	MEM_SWAPOUT,
	73	TIMERADD,
	74	SCSI_DISPATCH_CMD,
	75	IDE_CORE_CP
	76	};
	77
	78	enum ctype {
	79	NONE,
	80	PANIC,
	81	BUG,
	82	EXCEPTION,
	83	LOOP,
	84	OVERFLOW
	85	};
	86
	87	static char* cp_name[] = {
	88	"INT_HARDWARE_ENTRY",
	89	"INT_HW_IRQ_EN",
	90	"INT_TASKLET_ENTRY",
	91	"FS_DEVRW",
	92	"MEM_SWAPOUT",
	93	"TIMERADD",
	94	"SCSI_DISPATCH_CMD",
	95	"IDE_CORE_CP"
	96	};
	97
	98	static char* cp_type[] = {
	99	"PANIC",
	100	"BUG",
	101	"EXCEPTION",
	102	"LOOP",
	103	"OVERFLOW"
	104	};
	105
	106	static struct jprobe lkdtm;
	107
	108	static int lkdtm_parse_commandline(void);
	109	static void lkdtm_handler(void);
	110
ec1c620b AV	111	static char* cpoint_name;
ec1c620b AV	112	static char* cpoint_type;
8bb31b9d AG	113	static int cpoint_count = DEFAULT_COUNT;
	114	static int recur_count = REC_NUM_DEFAULT;
	115
	116	static enum cname cpoint = INVALID;
	117	static enum ctype cptype = NONE;
	118	static int count = DEFAULT_COUNT;
	119
	120	module_param(recur_count, int, 0644);
5d861d92 RD	121	MODULE_PARM_DESC(recur_count, " Recursion level for the stack overflow test, "\
5d861d92 RD	122	"default is 10");
8bb31b9d	123	module_param(cpoint_name, charp, 0644);
5d861d92 RD	124	MODULE_PARM_DESC(cpoint_name, " Crash Point, where kernel is to be crashed");
	125	module_param(cpoint_type, charp, 0644);
	126	MODULE_PARM_DESC(cpoint_type, " Crash Point Type, action to be taken on "\
	127	"hitting the crash point");
	128	module_param(cpoint_count, int, 0644);
	129	MODULE_PARM_DESC(cpoint_count, " Crash Point Count, number of times the "\
	130	"crash point is to be hit to trigger action");
8bb31b9d	131
2118116e	132	static unsigned int jp_do_irq(unsigned int irq)
8bb31b9d AG	133	{
	134	lkdtm_handler();
	135	jprobe_return();
	136	return 0;
	137	}
	138
2118116e AB	139	static irqreturn_t jp_handle_irq_event(unsigned int irq,
2118116e AB	140	struct irqaction *action)
8bb31b9d AG	141	{
	142	lkdtm_handler();
	143	jprobe_return();
	144	return 0;
	145	}
	146
2118116e	147	static void jp_tasklet_action(struct softirq_action *a)
8bb31b9d AG	148	{
	149	lkdtm_handler();
	150	jprobe_return();
	151	}
	152
2118116e	153	static void jp_ll_rw_block(int rw, int nr, struct buffer_head *bhs[])
8bb31b9d AG	154	{
	155	lkdtm_handler();
	156	jprobe_return();
	157	}
	158
	159	struct scan_control;
	160
2118116e AB	161	static unsigned long jp_shrink_inactive_list(unsigned long max_scan,
	162	struct zone *zone,
	163	struct scan_control *sc)
8bb31b9d AG	164	{
	165	lkdtm_handler();
	166	jprobe_return();
	167	return 0;
	168	}
	169
2118116e AB	170	static int jp_hrtimer_start(struct hrtimer *timer, ktime_t tim,
2118116e AB	171	const enum hrtimer_mode mode)
8bb31b9d AG	172	{
	173	lkdtm_handler();
	174	jprobe_return();
	175	return 0;
	176	}
	177
2118116e	178	static int jp_scsi_dispatch_cmd(struct scsi_cmnd *cmd)
8bb31b9d AG	179	{
	180	lkdtm_handler();
	181	jprobe_return();
	182	return 0;
	183	}
	184
	185	#ifdef CONFIG_IDE
	186	int jp_generic_ide_ioctl(ide_drive_t drive, struct file file,
	187	struct block_device *bdev, unsigned int cmd,
	188	unsigned long arg)
	189	{
	190	lkdtm_handler();
	191	jprobe_return();
	192	return 0;
	193	}
	194	#endif
	195
	196	static int lkdtm_parse_commandline(void)
	197	{
	198	int i;
	199
5cf83b9b	200	if (cpoint_name == NULL \|\| cpoint_type == NULL \|\|
8bb31b9d AG	201	cpoint_count < 1 \|\| recur_count < 1)
	202	return -EINVAL;
	203
	204	for (i = 0; i < NUM_CPOINTS; ++i) {
	205	if (!strcmp(cpoint_name, cp_name[i])) {
	206	cpoint = i + 1;
	207	break;
	208	}
	209	}
	210
	211	for (i = 0; i < NUM_CPOINT_TYPES; ++i) {
	212	if (!strcmp(cpoint_type, cp_type[i])) {
	213	cptype = i + 1;
	214	break;
	215	}
	216	}
	217
	218	if (cpoint == INVALID \|\| cptype == NONE)
	219	return -EINVAL;
	220
	221	count = cpoint_count;
	222
	223	return 0;
	224	}
	225
	226	static int recursive_loop(int a)
	227	{
	228	char buf[1024];
	229
	230	memset(buf,0xFF,1024);
	231	recur_count--;
	232	if (!recur_count)
	233	return 0;
	234	else
	235	return recursive_loop(a);
	236	}
	237
	238	void lkdtm_handler(void)
	239	{
	240	printk(KERN_INFO "lkdtm : Crash point %s of type %s hit\n",
	241	cpoint_name, cpoint_type);
	242	--count;
	243
	244	if (count == 0) {
	245	switch (cptype) {
	246	case NONE:
	247	break;
	248	case PANIC:
	249	printk(KERN_INFO "lkdtm : PANIC\n");
	250	panic("dumptest");
	251	break;
	252	case BUG:
	253	printk(KERN_INFO "lkdtm : BUG\n");
	254	BUG();
	255	break;
	256	case EXCEPTION:
	257	printk(KERN_INFO "lkdtm : EXCEPTION\n");
	258	((int ) 0) = 0;
	259	break;
	260	case LOOP:
	261	printk(KERN_INFO "lkdtm : LOOP\n");
	262	for (;;);
	263	break;
	264	case OVERFLOW:
265	printk(KERN_INFO "lkdtm : OVERFLOW\n");
266	(void) recursive_loop(0);
267	break;
268	default:
269	break;
270	}
271	count = cpoint_count;
272	}
273	}
274
2118116e	275	static int __init lkdtm_module_init(void)
8bb31b9d AG	276	{
	277	int ret;
	278
	279	if (lkdtm_parse_commandline() == -EINVAL) {
	280	printk(KERN_INFO "lkdtm : Invalid command\n");
	281	return -EINVAL;
	282	}
	283
	284	switch (cpoint) {
	285	case INT_HARDWARE_ENTRY:
f58f2fa9	286	lkdtm.kp.symbol_name = "do_IRQ";
8bb31b9d AG	287	lkdtm.entry = (kprobe_opcode_t*) jp_do_irq;
	288	break;
	289	case INT_HW_IRQ_EN:
	290	lkdtm.kp.symbol_name = "handle_IRQ_event";
	291	lkdtm.entry = (kprobe_opcode_t*) jp_handle_irq_event;
	292	break;
	293	case INT_TASKLET_ENTRY:
	294	lkdtm.kp.symbol_name = "tasklet_action";
	295	lkdtm.entry = (kprobe_opcode_t*) jp_tasklet_action;
	296	break;
	297	case FS_DEVRW:
	298	lkdtm.kp.symbol_name = "ll_rw_block";
	299	lkdtm.entry = (kprobe_opcode_t*) jp_ll_rw_block;
	300	break;
	301	case MEM_SWAPOUT:
18a61e4a AG	302	lkdtm.kp.symbol_name = "shrink_inactive_list";
18a61e4a AG	303	lkdtm.entry = (kprobe_opcode_t*) jp_shrink_inactive_list;
8bb31b9d AG	304	break;
	305	case TIMERADD:
	306	lkdtm.kp.symbol_name = "hrtimer_start";
	307	lkdtm.entry = (kprobe_opcode_t*) jp_hrtimer_start;
	308	break;
	309	case SCSI_DISPATCH_CMD:
	310	lkdtm.kp.symbol_name = "scsi_dispatch_cmd";
	311	lkdtm.entry = (kprobe_opcode_t*) jp_scsi_dispatch_cmd;
	312	break;
	313	case IDE_CORE_CP:
	314	#ifdef CONFIG_IDE
	315	lkdtm.kp.symbol_name = "generic_ide_ioctl";
	316	lkdtm.entry = (kprobe_opcode_t*) jp_generic_ide_ioctl;
	317	#else
	318	printk(KERN_INFO "lkdtm : Crash point not available\n");
	319	#endif
	320	break;
	321	default:
	322	printk(KERN_INFO "lkdtm : Invalid Crash Point\n");
	323	break;
	324	}
	325
	326	if ((ret = register_jprobe(&lkdtm)) < 0) {
	327	printk(KERN_INFO "lkdtm : Couldn't register jprobe\n");
	328	return ret;
	329	}
	330
	331	printk(KERN_INFO "lkdtm : Crash point %s of type %s registered\n",
	332	cpoint_name, cpoint_type);
	333	return 0;
	334	}
	335
2118116e	336	static void __exit lkdtm_module_exit(void)
8bb31b9d AG	337	{
	338	unregister_jprobe(&lkdtm);
	339	printk(KERN_INFO "lkdtm : Crash point unregistered\n");
	340	}
	341
	342	module_init(lkdtm_module_init);
	343	module_exit(lkdtm_module_exit);
	344
	345	MODULE_LICENSE("GPL");