kprobes: Remove the jprobes sample code

# builds the kprobes example kernel modules;

# then to use one (as root):  insmod <module_name.ko>

obj-$(CONFIG_SAMPLE_KPROBES) += kprobe_example.o jprobe_example.o

obj-$(CONFIG_SAMPLE_KPROBES) += kprobe_example.o

obj-$(CONFIG_SAMPLE_KRETPROBES) += kretprobe_example.o

/*

 * Here's a sample kernel module showing the use of jprobes to dump

 * the arguments of _do_fork().

 *

 * For more information on theory of operation of jprobes, see

 * Documentation/kprobes.txt

 *

 * Build and insert the kernel module as done in the kprobe example.

 * You will see the trace data in /var/log/messages and on the

 * console whenever _do_fork() is invoked to create a new process.

 * (Some messages may be suppressed if syslogd is configured to

 * eliminate duplicate messages.)

 */

#include <linux/kernel.h>

#include <linux/module.h>

#include <linux/kprobes.h>

/*

 * Jumper probe for _do_fork.

 * Mirror principle enables access to arguments of the probed routine

 * from the probe handler.

 */

/* Proxy routine having the same arguments as actual _do_fork() routine */

static long j_do_fork(unsigned long clone_flags, unsigned long stack_start,

	      unsigned long stack_size, int __user *parent_tidptr,

	      int __user *child_tidptr, unsigned long tls)

{

	pr_info("jprobe: clone_flags = 0x%lx, stack_start = 0x%lx "

		"stack_size = 0x%lx\n", clone_flags, stack_start, stack_size);

	/* Always end with a call to jprobe_return(). */

	jprobe_return();

	return 0;

}

static struct jprobe my_jprobe = {

	.entry			= j_do_fork,

	.kp = {

		.symbol_name	= "_do_fork",

	},

};

static int __init jprobe_init(void)

{

	int ret;

	ret = register_jprobe(&my_jprobe);

	if (ret < 0) {

		pr_err("register_jprobe failed, returned %d\n", ret);

		return -1;

	}

	pr_info("Planted jprobe at %p, handler addr %p\n",

	       my_jprobe.kp.addr, my_jprobe.entry);

	return 0;

}

static void __exit jprobe_exit(void)

{

	unregister_jprobe(&my_jprobe);

	pr_info("jprobe at %p unregistered\n", my_jprobe.kp.addr);

}

module_init(jprobe_init)

module_exit(jprobe_exit)

MODULE_LICENSE("GPL");