kprobes: Remove the jprobes sample code

Remove the jprobes sample module because jprobes are deprecated.
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: David S . Miller <davem@davemloft.net>
Cc: Ian McDonald <ian.mcdonald@jandi.co.nz>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E . McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephen Hemminger <stephen@networkplumber.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vlad Yasevich <vyasevich@gmail.com>
Link: http://lkml.kernel.org/r/150724535709.5014.7261513316230565780.stgit@devboxSigned-off-by: Ingo Molnar <mingo@kernel.org>

samples/kprobes/Makefile

 # 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

samples/kprobes/jprobe_example.c

-/*
- * 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");