linux-imx

/*

 * Linux Kernel Dump Test Module for testing kernel crashes conditions:

 * induces system failures at predefined crashpoints and under predefined

 * operational conditions in order to evaluate the reliability of kernel

 * sanity checking and crash dumps obtained using different dumping

 * solutions.

 *

 * 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>

 *

 * It is adapted from the Linux Kernel Dump Test Tool by

 * Fernando Luis Vazquez Cao <http://lkdtt.sourceforge.net>

 *

 * Debugfs support added by Simon Kagstrom <simon.kagstrom@netinsight.net>

 *

 * See Documentation/fault-injection/provoke-crashes.txt for instructions

 */

#include "lkdtm.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/slab.h>

#include <linux/debugfs.h>

​

#define DEFAULT_COUNT 10

​

static int lkdtm_debugfs_open(struct inode *inode, struct file *file);

static ssize_t lkdtm_debugfs_read(struct file *f, char __user *user_buf,

        size_t count, loff_t *off);

static ssize_t direct_entry(struct file *f, const char __user *user_buf,

                size_t count, loff_t *off);

​

#ifdef CONFIG_KPROBES

static int lkdtm_kprobe_handler(struct kprobe *kp, struct pt_regs *regs);

static ssize_t lkdtm_debugfs_entry(struct file *f,

                   const char __user *user_buf,

                   size_t count, loff_t *off);

# define CRASHPOINT_KPROBE(_symbol)             \

        .kprobe = {                 \

            .symbol_name = (_symbol),       \

            .pre_handler = lkdtm_kprobe_handler,    \

        },

# define CRASHPOINT_WRITE(_symbol)              \

        (_symbol) ? lkdtm_debugfs_entry : direct_entry

#else

# define CRASHPOINT_KPROBE(_symbol)

# define CRASHPOINT_WRITE(_symbol)      direct_entry

#endif

​

/* Crash points */

struct crashpoint {

    const char *name;

    const struct file_operations fops;

    struct kprobe kprobe;

};

​

#define CRASHPOINT(_name, _symbol)              \

    {                           \

        .name = _name,                  \

        .fops = {                   \

            .read   = lkdtm_debugfs_read,       \

            .llseek = generic_file_llseek,      \

            .open   = lkdtm_debugfs_open,       \

            .write  = CRASHPOINT_WRITE(_symbol) \

        },                      \

        CRASHPOINT_KPROBE(_symbol)          \

    }

​

/* Define the possible places where we can trigger a crash point. */

static struct crashpoint crashpoints[] = {

    CRASHPOINT("DIRECT",         NULL),

#ifdef CONFIG_KPROBES

    CRASHPOINT("INT_HARDWARE_ENTRY", "do_IRQ"),

    CRASHPOINT("INT_HW_IRQ_EN",  "handle_irq_event"),