[PATCH] disallow kprobes on notifier_call_chain

When kprobe is re-entered, the re-entered kprobe kernel path will will call
atomic_notifier_call_chain function, if this function is kprobed that will
incur numerous kprobe recursive fault.  This patch disallows kprobes on
atomic_notifier_call_chain function.
Signed-off-by: Nbibo, mao <bibo.mao@intel.com>
Signed-off-by: NAnanth N Mavinakayanahalli <ananth@in.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

kernel/sys.c

@@ -221,7 +221,7 @@ EXPORT_SYMBOL_GPL(atomic_notifier_chain_unregister);
  *	of the last notifier function called.
  */
  
-int atomic_notifier_call_chain(struct atomic_notifier_head *nh,
+int __kprobes atomic_notifier_call_chain(struct atomic_notifier_head *nh,
 		unsigned long val, void *v)
 {
 	int ret;