--- /dev/null
+/*
+ * 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 <ankita@in.ibm.com>
+ *
+ * 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/module.h>
+#include <linux/kprobes.h>
+#include <linux/kallsyms.h>
+#include <linux/init.h>
+#include <linux/irq.h>
+#include <linux/interrupt.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 = INVALID;
+static char* cpoint_type = NONE;
+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, "Recurcion 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, 06444);
+MODULE_PARM_DESC(cpoint_type, "Crash Point Type, action to be taken on\
+ hitting the crash point");
+module_param(cpoint_count, int, 06444);
+MODULE_PARM_DESC(cpoint_count, "Crash Point Count, number of times the \
+ crash point is to be hit to trigger action");
+
+unsigned int jp_do_irq(unsigned int irq, struct pt_regs *regs)
+{
+ lkdtm_handler();
+ jprobe_return();
+ return 0;
+}
+
+irqreturn_t jp_handle_irq_event(unsigned int irq, struct pt_regs *regs,
+ struct irqaction *action)
+{
+ lkdtm_handler();
+ jprobe_return();
+ return 0;
+}
+
+void jp_tasklet_action(struct softirq_action *a)
+{
+ lkdtm_handler();
+ jprobe_return();
+}
+
+void jp_ll_rw_block(int rw, int nr, struct buffer_head *bhs[])
+{
+ lkdtm_handler();
+ jprobe_return();
+}
+
+struct scan_control;
+
+unsigned long jp_shrink_page_list(struct list_head *page_list,
+ struct scan_control *sc)
+{
+ lkdtm_handler();
+ jprobe_return();
+ return 0;
+}
+
+int jp_hrtimer_start(struct hrtimer *timer, ktime_t tim,
+ const enum hrtimer_mode mode)
+{
+ lkdtm_handler();
+ jprobe_return();
+ return 0;
+}
+
+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 == INVALID || cpoint_type == NONE ||
+ 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;
+ }
+}
+
+int 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_page_list";
+ lkdtm.entry = (kprobe_opcode_t*) jp_shrink_page_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;
+}
+
+void 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");